Pervez Sultan, Visiting

View details for DOI 10.1007/s12630-020-01872-5

View details for PubMedID 33403553

View details for DOI 10.1016/j.ijoa.2021.102969

View details for PubMedID 33794439

Abstract

This narrative review discusses recent evidence surrounding the use of regional anaesthesia in the obstetric setting, including intrapartum techniques for labour and operative vaginal delivery, and caesarean delivery. Pudendal nerve blockade, ideally administered by an obstetrician, should be considered for operative vaginal delivery if neuraxial analgesia is contraindicated. Regional techniques are increasingly utilised in clinical practice for caesarean delivery to minimise opioid consumption, reduce pain, improve postpartum recovery and facilitate earlier discharge as part of enhanced recovery protocols. The evidence surrounding transversus abdominis plane and quadratus lumborum blockade supports their use when: long-acting neuraxial opioids cannot be administered due to contraindications; if emergency delivery necessitates general anaesthesia; or as a postoperative rescue technique. Current data suggest quadratus lumborum blockade is no more effective than transversus abdominis plane blockade after caesarean delivery. Transversus abdominis plane blockade, wound catheter insertion and single shot wound infiltration are all effective techniques for reducing postoperative opioid consumption, with transversus abdominis plane blockade favoured, followed by wound catheters and then wound infiltration. Ilio-inguinal and iliohypogastric, erector spinae plane and rectus sheath blockade all require further studies to determine their efficacy for caesarean delivery in the presence or absence of long-acting neuraxial opioids. Future studies are needed to: compare approaches for individual techniques; determine which combinations of techniques and dosing regimens result in optimal analgesic and recovery outcomes following delivery; and elucidate the populations that benefit most from regional anaesthesia in the obstetric setting.

View details for DOI 10.1111/anae.15233

View details for PubMedID 33426655

Abstract

General anaesthesia for obstetric surgery has distinct characteristics that may contribute towards a higher risk of accidental awareness during general anaesthesia. The primary aim of this study was to investigate the incidence, experience and psychological implications of unintended conscious awareness during general anaesthesia in obstetric patients. From May 2017 to August 2018, 3115 consenting patients receiving general anaesthesia for obstetric surgery in 72 hospitals in England were recruited to the study. Patients received three repetitions of standardised questioning over 30days, with responses indicating memories during general anaesthesia that were verified using interviews and record interrogation. A total of 12 patients had certain/probable or possible awareness, an incidence of 1 in 256 (95%CI 149-500) for all obstetric surgery. The incidence was 1 in 212 (95%CI 122-417) for caesarean section surgery. Distressing experiences were reported by seven (58.3%) patients, paralysis by five (41.7%) and paralysis with pain by two (16.7%). Accidental awareness occurred during induction and emergence in nine (75%) of the patients who reported awareness. Factors associated with accidental awareness during general anaesthesia were: high BMI (25-30kg.m-2 ); low BMI (<18.5kg.m-2 ); out-of-hours surgery; and use of ketamine or thiopental for induction. Standardised psychological impact scores at 30days were significantly higher in awareness patients (median (IQR [range]) 15 (2.7-52.0 [2-56]) than in patients without awareness 3 (1-9 [0-64]), p=0.010. Four patients had a provisional diagnosis of post-traumatic stress disorder. We conclude that direct postoperative questioning reveals high rates of accidental awareness during general anaesthesia for obstetric surgery, which has implications for anaesthetic practice, consent and follow-up.

View details for DOI 10.1111/anae.15385

View details for PubMedID 33434945

View details for DOI 10.1111/anae.15341

View details for PubMedID 33428235

View details for DOI 10.1213/ANE.0000000000005267

View details for PubMedID 33591090

Abstract

The original article was updated to amend number "0.09" in Table2a (instead "-0.09").

View details for DOI 10.1007/s12630-020-01839-6

View details for PubMedID 33089415

View details for DOI 10.1213/ANE.0000000000004991

View details for Web of Science ID 000562499800058

View details for Web of Science ID 000619264500261

View details for DOI 10.1213/ANE.0000000000004576

View details for PubMedID 31934906

Abstract

Accidental awareness during general anaesthesia (AAGA) is a complex and rare outcome to investigate in surgical patient populations, particularly obstetric patients. We report the protocol of the Direct Reporting of Awareness in Maternity patients (DREAMY) study, illustrating how the research was designed to address practical and methodological challenges for investigating AAGA in an obstetric cohort.This is the trial protocol of a prospective, multicentre cohort study of patients undergoing obstetric surgery under general anaesthesia. Accidental awareness during general anaesthesia will be detected using three repetitions of standardised direct questioning over 30days, with responses indicating memories during general anaesthesia verified using structured interviews. Reports will be adjudicated, then classified, in accordance with pre-defined and pre-validated structures, including the Michigan Awareness Classification tool. Quantitative data will be collected on general anaesthesia conduct for all participants. This descriptive study is being conducted in England and aims to recruit a minimum of 2015 patients.The DREAMY study was prospectively registered (ClinicalTrials.gov Identifier: NCT03100396) and ethical approval granted. Participant recruitment began in May 2017 and one year follow up concluded in August 2019. Publication of the results is anticipated in 2020.The DREAMY study will provide data on incidence, experience and implications of AAGA for obstetric patients, using a robust methodology that will reliably detect and translate subjective AAGA reports into objective outcomes. In addition, the study is expected to improve vigilance for AAGA in participating hospitals and encourage adoption of recommendations for support of patients experiencing AAGA.

View details for DOI 10.1016/j.ijoa.2020.02.004

View details for PubMedID 32139144

Abstract

With increasing numbers of Coronavirus Disease 2019 (COVID 19) cases due to efficient human-to-human transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the United States, preparation for the unpredictable setting of labor and delivery is paramount. The priorities are two-fold in the management of obstetric patients with COVID-19 infection or persons under investigation (PUI): (1) caring for the range of asymptomatic to critically ill pregnant and postpartum women; (2) protecting health care workers and beyond from exposure during the delivery hospitalization (health care providers, personnel, family members). The goal of this review is to provide evidence-based recommendations, or expert opinion when evidence is limited, for anesthesiologists caring for pregnant women during the COVID 19 pandemic, with a focus on preparedness and best clinical obstetric anesthesia practice.

View details for DOI 10.1213/ANE.0000000000004856

View details for PubMedID 32265365

Abstract

There are no current descriptions of general anaesthesia characteristics for obstetric surgery, despite recent changes to patient baseline characteristics and airway management guidelines. This analysis of data from the direct reporting of awareness in maternity patients' (DREAMY) study of accidental awareness during obstetric anaesthesia aimed to describe practice for obstetric general anaesthesia in England and compare with earlier surveys and best-practice recommendations. Consenting patients who received general anaesthesia for obstetric surgery in 72 hospitals from May 2017 to August 2018 were included. Baseline characteristics, airway management, anaesthetic techniques and major complications were collected. Descriptive analysis, binary logistic regression modelling and comparisons with earlier data were conducted. Data were collected from 3117 procedures, including 2554 (81.9%) caesarean deliveries. Thiopental was the induction drug in 1649 (52.9%) patients, compared with propofol in 1419 (45.5%). Suxamethonium was the neuromuscular blocking drug for tracheal intubation in 2631 (86.1%), compared with rocuronium in 367 (11.8%). Difficult tracheal intubation was reported in 1 in 19 (95%CI 1 in 16-22) and failed intubation in 1 in 312 (95%CI 1 in 169-667). Obese patients were over-represented compared with national baselines and associated with difficult, but not failed intubation. There was more evidence of change in practice for induction drugs (increased use of propofol) than neuromuscular blocking drugs (suxamethonium remains the most popular). There was evidence of improvement in practice, with increased monitoring and reversal of neuromuscular blockade (although this remains suboptimal). Despite a high risk of difficult intubation in this population, videolaryngoscopy was rarely used (1.9%).

View details for DOI 10.1111/anae.15250

View details for PubMedID 32959372

View details for DOI 10.1016/j.ijoa.2020.07.009

View details for PubMedID 32799064

View details for DOI 10.1213/ANE.0000000000004991

View details for PubMedID 33035031

Abstract

Personalised risk assessment of the likelihood of pulmonary aspiration is recommended for pregnant women undergoing general anaesthesia and gastric point-of-care ultrasound (PoCUS) may help to achieve this. Traditionally, risk assessment is based upon adherence to fasting times, but gastric emptying may vary during pregnancy and surgery often needs to be expedited. We systematically reviewed the evidence for gastric PoCUS up to August 2018 in pregnant and postpartum women to determine whether it can identify and quantify stomach contents, provide aspiration risk assessment via qualitative or quantitative means, and determine how gastric emptying is affected by pregnancy. Twenty-two articles comprising 1050 participants were included and studies were classified by qualitative or quantitative findings. The evidence suggests that gastric PoCUS is a reliable and feasible method of imaging the stomach in pregnancy in clinical practice. Qualitative assessment via the Perlas grading system can provide rapid assessment of gastric volume states. If fluid is visible, identification of patients at high risk of pulmonary aspiration requires measurement of antral cross-sectional area. Cut-off values of 608mm2 and 960mm2 are recommended in the semi-recumbent and right lateral semi-recumbent positions, respectively. Validated methods to quantify stomach volumes are available, however their usefulness is currently restricted to research. Gastric PoCUS also provides evidence that gastric emptying of ingested food is delayed by term pregnancy, labour and during the early postpartum period. However, the passage of fluids through the stomach appears unaffected throughout the peripartum period.

View details for DOI 10.1016/j.ijoa.2020.05.005

View details for PubMedID 32693329

Abstract

Elevated high-sensitivity troponin (hsTnT) after noncardiac surgery is associated with higher mortality, but the temporal relationship between early elevated troponin and the later development of noncardiac morbidity remains unclear.Prospective observational study of patients aged 45 yr undergoing major noncardiac surgery at four UK hospitals (two masked to hsTnT). The exposure of interest was early elevated troponin, as defined by hsTnT >99th centile (15 ng L-1) within 24 h after surgery. The primary outcome was morbidity 72 h after surgery, defined by the Postoperative Morbidity Survey (POMS). Secondary outcomes were time to become morbidity-free and Clavien-Dindo grade 3 complications.Early elevated troponin (median 21 ng L-1 [16-32]) occurred in 992 of 4335 (22.9%) patients undergoing elective noncardiac surgery (mean [standard deviation, sd] age, 65 [11] yr; 2385 [54.9%] male). Noncardiac morbidity was more frequent in 494/992 (49.8%) patients with early elevated troponin compared with 1127/3343 (33.7%) patients with hsTnT <99th centile (odds ratio [OR]=1.95; 95% confidence interval [CI], 1.69-2.25). Patients with early elevated troponin had a higher risk of proven/suspected infectious morbidity (OR=1.54; 95% CI, 1.24-1.91) and critical care utilisation (OR=2.05; 95% CI, 1.73-2.43). Clavien-Dindo grade 3 complications occurred in 167/992 (16.8%) patients with early elevated troponin, compared with 319/3343 (9.5%) patients with hsTnT <99th centile (OR=1.78; 95% CI, 1.48-2.14). Absence of early elevated troponin was associated with morbidity-free recovery (OR=0.44; 95% CI, 0.39-0.51).Early elevated troponin within 24 h of elective noncardiac surgery precedes the subsequent development of noncardiac organ dysfunction and may help stratify levels of postoperative care in real time.

View details for DOI 10.1016/j.bja.2020.02.003

View details for PubMedID 32147104

Abstract

The role of high flow nasal oxygenation (HFNO) for pre-oxygenation before obstetric general anaesthesia remains unclear. This study aimed to determine the number of vital capacity breaths using HFNO required to pre-oxygenate 90% of parturients to an end-tidal oxygen concentration fraction (FETO2) of 0.90 (termed EN90).Using up-down, sequential allocation trial design, volunteer term parturients undergoing caesarean delivery were investigated with HFNO with their mouths closed, followed by mouths open, and if FETO2 0.90 was not achieved after a maximum of 20 vital capacity breaths, pre-oxygenation was attempted with a face mask. The primary outcome was the number of vital capacity breaths required using HFNO (mouth open and closed) to achieve EN90. Secondary outcomes included assessment of EN90 using mouth open versus mouth closed and face mask pre-oxygenation, maternal satisfaction and evaluation of fetal cardiotocography.Twenty women at term were recruited. Successful pre-oxygenation occurred in 4 (20%), 3 (15%) and 14 (70%) women with HFNO mouth closed, HFNO mouth open, and via face mask respectively. At up to 20 vital capacity breaths, face mask pre-oxygenation was more successful at achieving EN90 compared with both HFNO with a closed (P=0.006) or open (P=0.001) mouth. Closed mouth HFNO did not outperform open-mouth pre-oxygenation.Face mask pre-oxygenation is more effective at achieving EN90 compared to HFNO within a clinically acceptable number of vital capacity breaths. Further studies are needed to determine the role of HFNO in optimising the time before desaturation and for apnoeic oxygenation in term parturients.

View details for DOI 10.1016/j.ijoa.2020.08.004

View details for PubMedID 33129656

Abstract

This systematic review and network meta-analysis (NMA) compared postoperative analgesic efficacy of transversus abdominis plane (TAP) blocks with that of wound infiltration for Cesarean delivery (CD) without long-acting neuraxial opioid administration.We sought randomized-controlled trials comparing TAP vs wound infiltration, and inactive control vs either TAP or wound infiltration. Wound infiltration included single-dose infiltration (WI), or continuous infusion via a catheter (WC). The primary outcome was 24 hr opioid consumption. Secondary outcomes included 12 and 24 hr pain scores (resting and movement), time to first analgesia request, incidence of postoperative nausea and vomiting (PONV), maternal sedation, and pruritus. We performed a NMA incorporating both direct and indirect comparisons and reported standardized mean differences and odds ratios with 95% confidence intervals for continuous and dichotomous outcomes.Forty-two studies were included, comprising 2,906 participants. Transversus abdominis plane blocks and WC were associated with significantly lower 24 hr opioid consumption than inactive controls, but there were no significant differences between WI and inactive controls. There was no statistically significant difference in 24 hr opioid consumption between TAP blocks and WC or WI techniques. The network ranking of treatments was TAP block, followed by WC or WI. No significant differences were shown between TAP, WC, and WI groups for 24 hr pain scores, time to first analgesia, PONV, sedation, and pruritus. Quality of evidence was moderate for most of the outcomes assessed.In the absence of long-acting neuraxial opioid after CD, single-dose TAP blocks and WC are effective opioid-sparing strategies.

View details for DOI 10.1007/s12630-020-01818-x

View details for PubMedID 33033957

Abstract

Caesarean delivery is the most commonly performed inpatient surgical procedure globally. Pain after caesarean delivery is moderate to severe if not adequately treated, and is a primary anaesthetic concern for patients. Transversus abdominis plane and quadratus lumborum blocks are fascial plane blocks that have the potential to improve analgesia following caesarean delivery. Although proponents of the quadratus lumborum block suggest that this technique may provide better analgesia compared with transversus abdominis plane block, there are limited data directly comparing these two techniques. We, therefore, performed a systematic review and network meta-analysis to compare transversus abdominis plane and quadratus lumborum block approaches, seeking randomised controlled trials comparing both techniques to each other, or to control, with or without intrathecal morphine. In all, 31 trials with 2188 patients were included and our primary outcome, the cumulative intravenous morphine equivalent consumption at 24h, was reported in 12 trials. In the absence of intrathecal morphine, transversus abdominis plane and quadratus lumborum blocks were equivalent, and both were superior to control (moderate-quality evidence). In the presence of intrathecal morphine, no differences were found between control, transversus abdominis plane and quadratus lumborum blocks (moderate-quality evidence). Similar results were found for resting and active pain scores at 4-6h, 8-12h, 24h and 36h, although quadratus lumborum block was associated with lower pain scores at 36h when compared with transversus abdominis plane block (very low-quality evidence). However, transversus abdominis plane block was associated with a reduced incidence of postoperative nausea and vomiting (moderate-quality evidence) and sedation when compared with inactive control following intrathecal morphine administration (low-quality evidence). There are insufficient data to draw definitive conclusions, but transversus abdominis plane and quadratus lumborum block appear to be superior to control in the absence of intrathecal morphine, but provide limited additional benefit over inactive control when intrathecal morphine is also used.

View details for DOI 10.1111/anae.15160

View details for PubMedID 32621529

View details for DOI 10.1213/ANE.0000000000004195

View details for Web of Science ID 000475951100036

View details for DOI 10.1016/j.ajog.2018.12.016

View details for Web of Science ID 000472481100020

View details for DOI 10.1097/ALN.0000000000002708

View details for Web of Science ID 000467856100003

Abstract

Systemic inflammation is pivotal in the pathogenesis of cardiovascular disease. As inflammation can directly cause cardiomyocyte injury, we hypothesised that established systemic inflammation, as reflected by elevated preoperative neutrophil-lymphocyte ratio (NLR) >4, predisposes patients to perioperative myocardial injury.We prospectively recruited 1652 patients aged 45 yr who underwent non-cardiac surgery in two UK centres. Serum high sensitivity troponin T (hsTnT) concentrations were measured on the first three postoperative days. Clinicians and investigators were blinded to the troponin results. The primary outcome was perioperative myocardial injury, defined as hsTnT14 ng L-1 within 3 days after surgery. We assessed whether myocardial injury was associated with preoperative NLR>4, activated reactive oxygen species (ROS) generation in circulating monocytes, or both. Multivariable logistic regression analysis explored associations between age, sex, NLR, Revised Cardiac Risk Index, individual leukocyte subsets, and myocardial injury. Flow cytometric quantification of ROS was done in 21 patients. Data are presented as n (%) or odds ratio (OR) with 95% confidence intervals.Preoperative NLR>4 was present in 239/1652 (14.5%) patients. Myocardial injury occurred in 405/1652 (24.5%) patients and was more common in patients with preoperative NLR>4 [OR: 2.56 (1.92-3.41); P<0.0001]. Myocardial injury was independently associated with lower absolute preoperative lymphocyte count [OR 1.80 (1.50-2.17); P<0.0001] and higher absolute preoperative monocyte count [OR 1.93 (1.12-3.30); P=0.017]. Monocyte ROS generation correlated with NLR (r=0.47; P=0.03).Preoperative NLR>4 is associated with perioperative myocardial injury, independent of conventional risk factors. Systemic inflammation may contribute to the development of perioperative myocardial injury.NCT01842568.

View details for DOI 10.1016/j.bja.2018.09.002

View details for PubMedID 30686303

View details for PubMedCentralID PMC6354048

Abstract

Epidural-related maternal fever (ERMF) has been reported in 26% of labouring women. The underlying mechanisms remain unclear. We hypothesised that ERMF is promoted by bupivacaine disrupting cytokine production/release from mononuclear leucocytes [mononuclear fraction (MNF)]. We examined whether bupivacaine (i) reduces caspase-1 activity and release of the anti-pyrogenic cytokine interleukin (IL)-1 receptor antagonist (IL-1ra), and (ii) is pro-inflammatory through mitochondrial injury/IL-1.In labouring women, blood samples were obtained before/after epidural analgesia was implemented. Maternal temperature was recorded hourly for the first 4 h of epidural analgesia. Time-matched samples/temperatures were obtained from labouring women without epidural analgesia, pregnant non-labouring, and non-pregnant women. The primary clinical outcome was change in maternal temperature over 4 h after the onset of siting epidural catheter/enrolment. The secondary clinical outcome was development of ERMF (temperature 38C). The effect of bupivacaine/saline on apoptosis, caspase-1 activity, intracellular IL-1ra, and plasma IL-1ra/IL-1 ratio was quantified in MNF from labouring women or THP-1 monocytes (using flow cytometry, respirometry, or enzyme-linked immunosorbent assay).Maternal temperature increased by 0.06C h-1 [95% confidence interval (CI): 0.03-0.09; P=0.003; n=38] after labour epidural placement. ERMF only occurred in women receiving epidural analgesia (five of 38; 13.2%). Bupivacaine did not alter MNF or THP-1 apoptosis compared with saline control, but reduced caspase-1 activity by 11% (95% CI: 5-17; n=10) in MNF from women in established labour. Bupivacaine increased intracellular MNF IL-1ra by 25% (95% CI: 10-41; P<0.001; n=10) compared with saline-control. Epidural analgesia reduced plasma IL-1ra/IL-1 ratio (mean reduction: 14; 95% CI: 7-30; n=30) compared with women without epidural analgesia.Impaired release of anti-pyrogenic IL-1ra might explain ERMF mechanistically. Immunomodulation by bupivacaine during labour could promote ERMF.

View details for DOI 10.1016/j.bja.2018.09.024

View details for PubMedID 30579413

Abstract

In this narrative review we summarise pertinent data from published studies investigating the use of local anaesthetic techniques as adjuncts for managing post caesarean delivery pain. Based on currently available evidence, ultrasound-guided transversus abdominis plane (TAP), quadratus lumborum (QL) and ilio-inguinal and iliohypogastric (ILIH) blocks are preferable to landmark techniques. When intrathecal morphine is used for caesarean delivery analgesia, TAP blocks do not confer any additional benefit. In the absence of intrathecal morphine, TAP blocks have been shown to reduce pain scores and opioid consumption in the first 24hours postoperatively. In the absence of intrathecal morphine, single-dose local anaesthetic wound infiltration also results in a moderate reduction in opioid consumption postoperatively. If a wound catheter is to be incorporated into a multimodal analgesic regimen, a position below the fascia and a continuous infusion of low-concentration local anaesthetic solutions should be considered. Intraperitoneal local anaesthetic instillation may be of benefit in patients who undergo peritoneal closure but larger studies are still needed. Quadratus lumborum and ILIH blocks show promising results but the data are limited, so recommendations for routine use cannot be made. In summary, evidence supports the use of local anaesthetic techniques for post-caesarean delivery pain but additional research is required to determine the optimum dosing regimens, and the potential role of liposomal local anaesthetics. Further studies are required to compare techniques and determine their role in conjunction with low-dose long-acting neuraxial opioids.

View details for DOI 10.1016/j.ijoa.2019.06.002

View details for PubMedID 31262444

View details for DOI 10.1017/9781316155479.049

View details for DOI 10.1017/9781316155479.022

Abstract

The prevalence of neuraxial opioid-induced clinically significant respiratory depression (CSRD) after cesarean delivery is unknown. We sought to review reported cases of author-reported respiratory depression (ARD) to calculate CSRD prevalence. A 6-database literature search was performed to identify ARD secondary to neuraxial morphine or diamorphine, in parturients undergoing cesarean delivery. "Highest" (definite and probable/possible) and "lowest" (definite) prevalences of CSRD were calculated. Secondary outcomes included: (1) prevalence of CSRD associated with contemporary doses of neuraxial opioid, (2) prevalence of ARD as defined by each study's own criteria, (3) case reports of ARD, and (4) reports of ARD reported by the Anesthesia Closed Claims Project database between 1990 and 2016. We identified 78 articles with 18,455 parturients receiving neuraxial morphine or diamorphine for cesarean delivery. The highest and lowest prevalences of CSRD with all doses of neuraxial opioids were 8.67 per 10,000 (95% CI, 4.20-15.16) and 5.96 per 10,000 (95% CI, 2.23-11.28), respectively. The highest and lowest prevalences of CSRD with the use of clinically relevant doses of neuraxial morphine ranged between 1.63 per 10,000 (95% CI, 0.62-8.77) and 1.08 per 10,000 (95% CI, 0.24-7.22), respectively. The prevalence of ARD as defined by each individual paper was 61 per 10,000 (95% CI, 51-74). One published case report of ARD met our inclusion criteria, and there were no cases of ARD from the Closed Claims database analysis. These results indicate that the prevalence of CSRD due to neuraxial morphine or diamorphine in the obstetric population is low.

View details for PubMedID 30004934

View details for PubMedID 29343417

Abstract

To evaluate the effect of high-frequency jet ventilation (HFJV) in place of standard intermittent positive-pressure ventilation (IPPV) on procedure duration, patient radiation dose, complication rates, and outcomes during CT-guided cryoablation of small renal tumours.One hundred consecutive CT-guided cryoablation procedures to treat small renal tumours under general anaesthesia were evaluated-50 with standard IPPV and 50 after the introduction of HFJV as standard practice. Anaesthesia and procedural times, ionising radiation dose, complications, and 1-month post-treatment outcomes were collected.HFJV was feasible and safe in all cases. Mean procedure time and total anaesthetic time were shorter with HFJV (p=<0.0001). The number of required CT acquisitions (p=0.0002) and total procedure patient radiation dose (p=0.0027) were also lower in the HFJV group compared with the IPPV group. There were a total of four complications of Clavien-Dindo classification 3 or above-three in the IPPV group and one in the HFJV group. At 1-month follow-up, two cases (both in the IPPV group) demonstrated subtotal treatment. Both cases were subsequently successfully retreated with cryoablation.By reducing target tumour motion during CT-guided renal cryoablation, HFJV can reduce procedure times and exposure to ionising radiation. HFJV provides an important adjunct to complex image-guided interventions, with potential to improve safety and treatment outcomes.

View details for PubMedID 29516243

View details for PubMedCentralID PMC5976690

View details for DOI 10.1016/j.bja.2017.11.050

View details for Web of Science ID 000439023600030

Abstract

The objective of this meta-analysis was to determine the efficacy of glycopyrrolate at reducing spinal hypotension during cesarean delivery.A literature search was performed to identify randomized controlled trials investigating the effect of glycopyrrolate on spinal-induced hypotension during cesarean delivery. Primary outcomes were intraoperative hypotension and vasopressor requirement (phenylephrine equivalents). Secondary outcomes included heart rate (HR), nausea and vomiting, dry mouth, and Apgar scores. Risk ratios (RRs), and mean differences (MDs) were calculated using random-effects modeling with 95% confidence intervals for primary outcomes and 99% confidence intervals for secondary outcomes.Five randomized controlled trials met our inclusion criteria. A total of 311 patients were included: 153 received glycopyrrolate and 158 placebo. The incidence of spinal-induced hypotension was no different with prophylactic glycopyrrolate compared to control (RR, 0.93 [0.71-1.21]; P = .59), but the total phenylephrine dose required was significantly reduced with glycopyrrolate (MD, -62.64 g [-107.61 to -17.66 g]; P = .006). The maximal HR achieved in the glycopyrrolate group was significantly higher compared to controls (MD, 15.85 bpm [5.40-26.31]; P < .0001); however, the incidence of bradycardia was not statistically different. The incidence of intraoperative nausea and vomiting was not different between groups; however, glycopyrrolate increased the risk of dry mouth (RR, 5.15 [1.82-14.57]; P < .0001). Apgar scores at 1 and 5 minutes did not differ between groups.Prophylactic glycopyrrolate does not reduce the incidence of spinal-induced hypotension but results in a modest reduction in vasopressor requirements while increasing maternal HR.

View details for PubMedID 28704246

Abstract

The optimal local-anaesthetic (LA) dose for transversus-abdominis-plane (TAP) block is unclear. In this meta-analysis, we aimed to determine whether TAP blocks for Caesarean delivery (CD) with low-dose (LD) LA demonstrated non-inferiority in terms of analgesic efficacy, compared with high-dose (HD) LA.A literature search was performed for randomised controlled trials examining the analgesic efficacy of TAP blocks vs control after CD. The different dosing used in these studies was classified as HD or LD (bupivacaine equivalents >50 or 50 mg per block side, respectively). The pooled results of each dose group vs control were indirectly compared using the Q test. The primary outcome was 24 h opioid consumption. Secondary outcomes included 6 and 24 h postoperative pain scores, time to first analgesia, 6 h opioid consumption, opioid-related side-effects, and maternal satisfaction.Fourteen studies consisting of 770 women (389 TAP and 381 control) were included. Compared with controls, the 24 h opioid consumption (milligram morphine equivalents) was lower in HD [mean difference (MD) 95% confidence interval (CI) -22.41 (-38.56, -6.26); P=0.007; I2=93%] and LD [MD 95% CI -16.29 (-29.74, -2.84); P=0.02; I2=98%] TAP groups. However, no differences were demonstrated between the HD and LD groups (P=0.57). There were also no differences between the HD and LD groups for the 6 h opioid consumption, time to first analgesia, 6 and 24 h pain scores, postoperative nausea and vomiting, pruritus, and maternal satisfaction.Low-dose TAP blocks for Caesarean delivery provide analgesia and opioid-sparing effects comparable with the high-dose blocks. This suggests that lower doses can be used to reduce local anaesthetic toxicity risk without compromising the analgesic efficacy.

View details for PubMedID 29406174

Abstract

We conducted a 5-year retrospective cohort study on women undergoing caesarean section to investigate factors influencing the operating room-to-incision interval. Time-to-event analysis was performed for category-1 caesarean section using a Cox proportional hazards regression model. Covariates included: anaesthetic technique; body mass index; age; parity; time of delivery; and gestational age. Binary logistic regression was performed for 5-min Apgar score 7. There were 677 women who underwent category-1 caesarean section and who met the entry criteria. Unadjusted median (IQR [range]) operating room-to-incision intervals were: epidural top-up 11 (7-17 [0-87]) min; general anaesthesia 6 (4-11 [0-69]) min; spinal 13 (10-20 [0-83]) min; and combined spinal-epidural 24 (13-35 [0-75]) min. Cox regression showed general anaesthesia to be the most rapid method with a hazard ratio (95%CI) of 1.97 (1.60-2.44; p<0.0001), followed by epidural top-up (reference group), spinal anaesthesia 0.79 (0.65-0.96; p=0.02) and combined spinal-epidural 0.48 (0.35-0.67; p<0.0001). Underweight and overweight body mass indexes were associated with longer operating room-to-incision intervals. General anaesthesia was associated with fewer 5-min Apgar scores 7 with an odds ratio (95%CI) of 0.28 (0.11-0.68; p<0.01). There was no difference in neonatal outcomes between the first and fifth quintiles for operating room-to-incision intervals. General anaesthesia is associated with the most rapid operating room-to-incision interval for category-1 caesarean section, but is also associated with worse short term neonatal outcomes. Longer operating room-to-incision intervals were not associated with worse neonatal outcomes.

View details for DOI 10.1111/anae.14296

View details for PubMedID 29633251

Abstract

Regional anesthesia is a rapidly growing subspecialty. There are few published meta-analyses exploring pain outcome measures utilised in regional anesthesia randomized controlled trials (RCTs), which may be due to heterogeneity in outcomes assessed. This systematic review explores postoperative pain outcomes utilised in regional anesthesia RCTs.A literature search was performed using three databases (Medline, Embase, and CINAHL). Regional anesthesia RCTs with postoperative pain as a primary outcome were included if written in English and published in one of the top 20 impact factor journals between 2005 and 2017. Study quality was assessed using the Cochrane Collaboration's tool for assessing risk of bias.From the 31 included articles, 15 different outcome measures in total were used to assess postoperative pain. The most commonly (16/31) used outcome measures were verbal numerical grading of pain out of 10, total opioid consumption, and visual analogue scale 10cm (VAS). The need for analgesia was used as an outcome measure where studies did not use a pain rating score. Ten studies reported pain scores on activity and 27/31 studies utilised 2 pain outcomes. Time of measurement of pain score also varied with a total of 51 different time points used in total.Analysis of the articles demonstrated heterogeneity and inconsistency in choice of pain outcome and time of measurement within regional anesthesia studies. Identification of these pain outcomes utilised can help to create a definitive list of core outcomes, which may guide future researchers when designing such studies.

View details for PubMedID 30151005

View details for PubMedCentralID PMC6087609

Abstract

Little is known about the relationship between perioperative high-sensitivity troponin T (hsTnT) measurements and 30-day mortality and myocardial injury after noncardiac surgery (MINS).To determine the association between perioperative hsTnT measurements and 30-day mortality and potential diagnostic criteria for MINS (ie, myocardial injury due to ischemia associated with 30-day mortality).Prospective cohort study of patients aged 45 years or older who underwent inpatient noncardiac surgery and had a postoperative hsTnT measurement. Starting in October 2008, participants were recruited at 23 centers in 13 countries; follow-up finished in December 2013.Patients had hsTnT measurements 6 to 12 hours after surgery and daily for 3 days; 40.4% had a preoperative hsTnT measurement.A modified Mazumdar approach (an iterative process) was used to determine if there were hsTnT thresholds associated with risk of death and had an adjusted hazard ratio (HR) of 3.0 or higher and a risk of 30-day mortality of 3% or higher. To determine potential diagnostic criteria for MINS, regression analyses ascertained if postoperative hsTnT elevations required an ischemic feature (eg, ischemic symptom or electrocardiography finding) to be associated with 30-day mortality.Among 21842 participants, the mean age was 63.1 (SD, 10.7) years and 49.1% were female. Death within 30 days after surgery occurred in 266 patients (1.2%; 95% CI, 1.1%-1.4%). Multivariable analysis demonstrated that compared with the reference group (peak hsTnT <5 ng/L), peak postoperative hsTnT levels of 20 to less than 65 ng/L, 65 to less than 1000 ng/L, and 1000 ng/L or higher had 30-day mortality rates of 3.0% (123/4049; 95% CI, 2.6%-3.6%), 9.1% (102/1118; 95% CI, 7.6%-11.0%), and 29.6% (16/54; 95% CI, 19.1%-42.8%), with corresponding adjusted HRs of 23.63 (95% CI, 10.32-54.09), 70.34 (95% CI, 30.60-161.71), and 227.01 (95% CI, 87.35-589.92), respectively. An absolute hsTnT change of 5 ng/L or higher was associated with an increased risk of 30-day mortality (adjusted HR, 4.69; 95% CI, 3.52-6.25). An elevated postoperative hsTnT (ie, 20 to <65 ng/L with an absolute change 5 ng/L or hsTnT 65 ng/L) without an ischemic feature was associated with 30-day mortality (adjusted HR, 3.20; 95% CI, 2.37-4.32). Among the 3904 patients (17.9%; 95% CI, 17.4%-18.4%) with MINS, 3633 (93.1%; 95% CI, 92.2%-93.8%) did not experience an ischemic symptom.Among patients undergoing noncardiac surgery, peak postoperative hsTnT during the first 3 days after surgery was significantly associated with 30-day mortality. Elevated postoperative hsTnT without an ischemic feature was also associated with 30-day mortality.

View details for DOI 10.1001/jama.2017.4360

View details for Web of Science ID 000400014000014

View details for PubMedID 28444280

View details for DOI 10.1016/j.ijoa.2016.11.003

View details for PubMedID 28017512

View details for PubMedID 28050017

Abstract

Medical identification jewellery can convey vital information to emergency responders, but mistakes and ambiguity may lead to misdiagnosis and morbidity. We performed a review of relevant articles retrieved from Pubmed , Embase and Scopus and Google UK Inc. to investigate the commercial availability and issuance of these products. From 84 identified studies, we shortlisted 74 for review. The Google search retrieved 1,090,000 results within 0.57 s (January 2017). We explored 32 websites selling medical alert jewellery in the first five pages of these results. We found that patients themselves are currently responsible for the engraved wording on medical alert jewellery, with no mandatory physician checks. The accuracy and appropriateness of this information may thus vary. In the absence of national guidance in the UK, we suggest that there should be a list of specific indications warranting their use, a requirement for regular review of information, and clarity around the level of physician input into the engraving chosen. We discuss the potential benefits vs. risks of wearing medical alert jewellery and clarify the limitations of medical teams' responsibilities in relation to patients found to be wearing them.

View details for DOI 10.1111/anae.13958

View details for PubMedID 28677832

View details for PubMedID 29121314

Abstract

Neuraxial blockade may increase external cephalic version (ECV) success rates. This survey aimed to assess the frequency and characteristics of neuraxial blockade used to facilitate ECV.We surveyed Society for Obstetric Anesthesia and Perinatology members regarding ECV practice using a 15-item survey developed by 3 obstetric anesthesiologists and tested for face validity. The survey was e-mailed in January 2015 and again in February 2015 to the 1056 Society of Obstetric Anesthesiology and Perinatology members. We present descriptive statistics of responses.Our survey response rate was 322 of 1056 (30.5%).Neuraxial blockade was used for ECV always by 18 (5.6%), often by 52 (16.1%), sometimes by 98 (30.4%), rarely by 78 (24.2%), and never by 46 (14.3%) of respondents. An anesthetic sensory block target was selected by 141 (43.8%) respondents, and analgesic by 102 (31.7%) respondents. Epidural drug doses ranged widely, including sufentanil 5-25 g; lidocaine 1% or 2% 10-20 mL, bupivacaine 0.0625% to 0.5% 6-15 mL, and ropivacaine 0.2% 20 mL. Intrathecal bupivacaine was used by 182 (56.5%) respondents; the most frequent doses were 2.5 mg used by 24 (7.5%), 7.5 mg used by 35 (10.9%), and 12 mg used by 30 (9.3%).Neuraxial blockade is not universally offered to facilitate ECV, and there is wide variability in neuraxial blockade techniques, in drugs and doses administered, and in the sensory blockade (anesthetic or analgesic) targeted. Future studies need to evaluate and remove barriers to allow for more widespread use of neuraxial blockade for pain relief and to optimize ECV success rates.

View details for DOI 10.1016/j.jclinane.2016.05.040

View details for PubMedID 27687460

View details for PubMedID 27423524

Abstract

The intrathecal morphine dose achieving optimal analgesia for cesarean delivery while minimizing side effects has not yet been deduced. In this meta-analysis, our objective was to determine whether low- or high-dose intrathecal morphine provides acceptable duration and intensity of analgesia with fewer side effects.A literature search (PubMed, EMBASE, MEDLINE, Scopus, Web of Science, and CINAHL) was performed to identify randomized controlled trials involving patients undergoing elective cesarean delivery under spinal anesthesia comparing low-dose (LD; 50-100 g) morphine with higher dose (HD; >100-250 g). The primary outcome was the time for first request for supplemental analgesia. The secondary outcomes included pain scores, morphine use, maternal side effects (vomiting and pruritus), and Apgar scores. Mean differences (MDs) and odds ratios (ORs) were calculated using random effects modeling with 95% confidence intervals (CIs).Eleven articles met our inclusion criteria. Four hundred eighty patients were recruited in all study groups (233 patients in the HD and 247 in the LD groups). The mean time to first analgesic request was longer (MD, 4.49 hours [95% CI, 1.85-7.13]; P = 0.0008) in the HD group compared with the LD group. Pain scores (0-100 scale) at 12 hours (MD, 2.54 [95% CI, -2.55 to 7.63]; P = 0.33) as well as morphine consumption at 24 hours (MD, 1.31 mg [95% CI, -3.06 to 7.31]; P = 0.42) were not significantly different. The incidence of nausea or vomiting (OR, 0.44 [95% CI, 0.27-0.73]; P = 0.002) and pruritus (OR, 0.34 [95% CI, 0.20-0.59]; P = 0.0001) was lower in the LD group. The incidence of Apgar scores <7 at 1 minute was not different between groups (OR, 1.11 [95% CI, 0.06-20.49]; P = 0.94).This meta-analysis shows that HDs of intrathecal morphine prolong analgesia after cesarean delivery compared with lower doses. The MD of 4.5 hours (95% CI, 1.9-7.1 and 99% CI, 1.0-8.2 hours) of pain relief must be balanced against the increased risk of maternal pruritus and vomiting. Results from this study can be used by clinicians to weigh the benefits and potential side effects of using HDs of intrathecal morphine for cesarean delivery.

View details for DOI 10.1213/ANE.0000000000001255

View details for PubMedID 27089000

Abstract

This article reviews our current understanding of amniotic fluid embolism (AFE), specifically the pathogenesis, treatment strategies, potential diagnostic tests and future therapeutic interventions for AFE.The incidence and case mortality of AFE varies widely because of heterogeneous diagnostic criteria and varying reporting mechanisms across the world. Amniotic fluid embolism is thought to be caused by abnormal activation of immunologic mechanisms following entry of fetal antigens into maternal circulation. Mast cell degranulation and complement activation may play a role in this anaphylactoid or systemic inflammatory response syndrome. Development of serum biomarkers and immune-histochemical staining techniques to aid diagnosis and develop treatments are under development and evaluation. Treatment of AFE is supportive and directed at treating cardiovascular, pulmonary, and coagulation derangements. Treatment for coagulopathy (fresh frozen plasma, cryoprecipitate/fibrinogen concentrate, and antifibrinolytics) should be initiated promptly. Recombinant factor VIIa may lead to increased mortality and should not routinely be used. C1 esterase inhibitors may be a potential therapeutic option.AFE is a devastating obstetric complication that requires early and aggressive intervention with optimal cardiopulmonary resuscitation, as well as hemorrhage and coagulopathy management. Biomarkers offer promise to aid the diagnosis of AFE, and immunomodulation may provide future therapeutic interventions to treat this lethal condition.

View details for DOI 10.1097/ACO.0000000000000328

View details for PubMedID 27153475

Abstract

Intrapartum fever is associated with excessive maternal interventions as well as higher neonatal morbidity. Epidural-related maternal fever (ERMF) contributes to the development of intrapartum fever. The mechanism(s) for ERMF has remained elusive. Here, we consider how inflammatory mechanisms may be modulated by local anesthetic agents and their relevance to ERMF. We also critically reappraise the clinical data with regard to emerging concepts that explain how anesthetic drug-induced metabolic dysfunction, with or without activation of the inflammasome, might trigger the release of nonpathogenic, inflammatory molecules (danger-associated molecular patterns) likely to underlie ERMF.

View details for PubMedID 27101499

Abstract

The phenomenon of pregnancy-induced analgesia has been demonstrated in animal models but less consistently in human studies. This study aimed to assess endogenous pain modulation, evaluating inhibitory and excitatory pain pathways, over the course of pregnancy and postpartum.Healthy pregnant women were approached for participation in this prospective multicenter cohort study. Conditioned pain modulation (CPM), mechanical temporal summation (mTS), and temperature that induced pain 6 out of 10 (pain-6) were assessed toward the end of each trimester of pregnancy (8-12, 18-22, and 36 weeks) and at 6 to 12 weeks postpartum. To assess how pregnancy affects CPM, mTS, and pain-6, a mixed-effects analysis of variance was performed.Thirty-three pregnant women were enrolled. Pregnancy did not significantly impact CPM (F3,39 = 0.30, P = 0.83, partial = 0.02), and there was no significant difference between CPM scores in the third trimester compared with postpartum. The mTS scores and pain-6 ratings were also not significantly changed by pregnancy (F3,42 = 1.20, P = 0.32, partial = 0.08; and F3,42 = 1.90, P = 0.14, partial = 0.12, respectively).This is the first study to assess CPM and mTS changes in pregnancy and postpartum. Endogenous pain modulation evaluating both inhibitory and excitatory pain pathways did not significantly change during pregnancy or postpartum. Future studies are required to determine the magnitude and clinical significance of pregnancy-induced analgesia.

View details for DOI 10.1097/AAP.0000000000000359

View details for PubMedID 26866295

Abstract

Introduction. This study aimed to determine if preoperative psychological tests combined with simple pain prediction ratings could predict pain intensity and analgesic usage following cesarean delivery (CD). Methods. 50 healthy women undergoing scheduled CD with spinal anesthesia comprised the prospective study cohort. Preoperative predictors included 4 validated psychological questionnaires (Anxiety Sensitivity Index (ASI), Fear of Pain (FPQ), Pain Catastrophizing Scale, and Eysenck Personality Questionnaire) and 3 simple ratings: expected postoperative pain (0-10), anticipated analgesic threshold (0-10), and perceived analgesic needs (0-10). Postoperative outcome measures included post-CD pain (combined rest and movement) and opioid used for the 48-hour study period. Results. Bivariate correlations were significant with expected pain and opioid usage (r = 0.349), anticipated analgesic threshold and post-CD pain (r = -0.349), and perceived analgesic needs and post-CD pain (r = 0.313). Multiple linear regression analysis found that expected postoperative pain and anticipated analgesic needs contributed to post-CD pain prediction modeling (R (2) = 0.443, p < 0.0001); expected postoperative pain, ASI, and FPQ were associated with opioid usage (R (2) = 0.421, p < 0.0001). Conclusion. Preoperative psychological tests combined with simple pain prediction ratings accounted for 44% and 42% of pain and analgesic use variance, respectively. Preoperatively determined expected postoperative pain and perceived analgesic needs appear to be useful predictors for post-CD pain and analgesic requirements.

View details for DOI 10.1155/2016/7948412

View details for PubMedID 27143966

View details for DOI 10.1093/bja/aew351

View details for PubMedID 27799193

Abstract

Low anaerobic threshold (AT), a marker of decreased exercise capacity, is associated with poorer outcomes following surgery. In this thesis I demonstrate a relationship between low preoperative AT and preoperative lymphopenia (low lymphocyte count). I subsequently demonstrate that preoperative lymphopenia is associated with prolonged hospitalisation and increased postoperative complications in 2 surgical cohorts (n=240 and n=881). Significant metabolic (bioenergetic) and functional changes occur in lymphocytes postoperatively, which may contribute to increased morbidity and mortality. Lymphocytes demonstrate a postoperative decrease in glycolysis and oxidative phosphorylation. Altered postoperative bioenergetic function are accompanied by an increase in mitochondrial reactive oxygen species production and a reduction in lymphocyte mitochondrial membrane potential, which are associated with apoptosis or cell death. Increased apoptosis of lymphocytes following surgery is the likely mechanism for acquired lymphopenia postoperatively (reduction in lymphocyte count which occurs postoperatively). A decrease in glycolysis is accompanied by increased CD8+ lymphocyte cytokine production. Postoperative inflammasome activation as demonstrated by increased caspase-1 activity, appears to occur secondary to glucocorticoid release associated with the stress response to surgery. Caspase-1 is associated with glycolysis inhibition (decreased glycolysis postoperatively) and increased apoptosis (reduced lymphocyte count postoperatively). Increased Interleukin-1-beta expression, which is associated with activation of the inflammasome and increased cytokine production, is demonstrated following incubation of lymphocytes with glucocorticoid. I hypothesise that postoperative changes in lymphocyte function occur secondary to increased glucocorticoid levels activating the inflammasome pathway during the stress response to surgery. This thesis provides translational data introducing the concept that lymphocyte metabolic abnormalities underlie the postoperative immune phenotype.

View details for DOI 10.1093/bja/aev325

View details for Web of Science ID 000362305700007

View details for PubMedID 26385660

Abstract

Perioperative lymphopenia has been linked with an increased risk of postoperative infectious complications, but the mechanisms remain unclear. We tested the hypothesis that bioenergetic dysfunction is an important mechanism underlying lymphopenia, impaired functionality and infectious complications. In two cohorts of patients (61-82years old) undergoing orthopaedic joint replacement (n=417 and 328, respectively), we confirmed prospectively that preoperative lymphopenia (1.3 x 10(9)l(-1); <20% white cell count; prevalence 15-18%) was associated with infectious complications (relative risk 1.5 (95% confidence interval 1.1-2.0); P=0.008) and prolonged hospital stay. Lymphocyte respirometry, mitochondrial bioenergetics and function were assessed (n=93 patients). Postoperative lymphocytes showed a median 43% fall (range: 26-65%; P=0.029; n=13 patients) in spare respiratory capacity, the extra capacity available to produce energy in response to stress. This was accompanied by reduced glycolytic capacity. A similar hypometabolic phenotype was observed in lymphocytes sampled preoperatively from chronically lymphopenic patients (n=21). This hypometabolic phenotype was associated with functional lymphocyte impairment including reduced T-cell proliferation, lower intracellular cytokine production and excess apoptosis induced by a range of common stressors. Glucocorticoids, which are ubiquitously elevated for a prolonged period postoperatively, generated increased levels of mitochondrial reactive oxygen species, activated caspase-1 and mature interleukin (IL)-1 in human lymphocytes, suggesting inflammasome activation. mRNA transcription of the NLRP1 inflammasome was increased in lymphocytes postoperatively. Genetic ablation of the murine NLRP3 inflammasome failed to prevent glucocorticoid-induced lymphocyte apoptosis and caspase-1 activity, but increased NLRP1 protein expression. Our findings suggest that the hypometabolic phenotype observed in chronically lymphopenic patients and/or acquired postoperatively increases the risk of postoperative infection through glucocorticoid activation of caspase-1 via the NLRP1 inflammasome.

View details for PubMedID 25891048

View details for PubMedID 25977453

Abstract

Malaria is a life-threatening infectious disease caused by the Plasmodium parasite. Increased global travel has resulted in an escalation in the number of imported cases seen in developed countries. Patients with malaria may present for surgery in both endemic and non-endemic countries. This article reviews the perioperative considerations when managing patients with malaria.A literature review of anesthesia, perioperative care, and malaria-related articles was performed using the MEDLINE(), EMBASE, and Web of Science databases to identify relevant articles published in English during 1945-2014. Of the 303 articles matching the search criteria, 265 were excluded based on title and abstract. Eleven of the remaining 38 articles were relevant to anesthesia/perioperative care, and 27 articles were identified as having direct relevance to critical care medicine.The majority of imported malaria cases are caused by the falciparum species, which is associated with the greatest degree of morbidity and mortality. Various organ systems may be impacted as a consequence of changes in the structure and function of parasitized erythrocytes. Preoperative assessment should focus on establishing the species of malaria, the severity of disease, assessing the degree of end-organ impairment, and initiating treatment of malaria prior to surgery. Intravenous artesunate is the treatment of choice for severe falciparum malaria. Quinine is a second-line agent but has a narrow therapeutic index and particularly hazardous side effects. Intraoperatively, attention should focus on fluid management, dynamics of cerebral blood flow, and avoidance of hypoglycemia. Postoperative care of severe cases should ideally take place in a critical care unit as there may be ongoing requirements for multi-organ support, including renal replacement therapy, ventilation, and/or inotropic support. The safety of neuraxial anesthesia has not been well studied in the setting of malaria.Malaria remains one of the most devastating infectious diseases worldwide. Multiple organ systems can be impacted as a consequence of changes in structure and function of parasitized erythrocytes. Safe perioperative management requires a sound knowledge of all these potential system effects.

View details for DOI 10.1007/s12630-014-0286-7

View details for Web of Science ID 000349912900010

View details for PubMedID 25471683

Abstract

Ondansetron is the drug of choice to prevent nausea in women undergoing cesarean surgery and can be used to prevent neonatal abstinence syndrome (NAS). The pharmacokinetics of ondansetron have not been characterized in pregnant women or in newborns. A nonlinear mixed-effects modeling approach was used to analyze plasma samples obtained from 20 nonpregnant and 40 pregnant women following a single administration of 4 or 8 mg ondansetron, from umbilical cord blood at delivery, and from neonates after birth. The analysis indicates that: ondansetron disposition is not affected by pregnancy (P > 0.05), but influenced by dose (P < 0.05), and is characterized by rapid transplacental transfer and longer elimination half-life in neonates compared to their mother. A dosing regimen for prevention of NAS was designed based on the model. The regimen involves IV administration of 4 mg to the mothers shortly before cord clamping, or oral administration of 0.07 mg/kg (or equivalently 0.04 mg/kg IV) to neonates.

View details for DOI 10.1002/cpt.5

View details for PubMedID 25670522

View details for PubMedCentralID PMC4325425

Abstract

Background. There is no consensus on the optimum management of failed tracheal intubation in emergency cesarean delivery performed for fetal compromise. The decision making process on whether to wake the patient or continue anesthesia with a supraglottic airway device is an underexplored area. This survey explores perceptions and experiences of obstetric anesthetists managing failed intubation. Methods. Anesthetists attending the Group of Obstetric Anaesthetists London (GOAL) Meeting in April 2014 were surveyed. Results. Ninety-three percent of anesthetists surveyed would not always wake the patient in the event of failed intubation for emergency cesarean delivery performed for fetal compromise. The median (interquartile range) of perceived acceptability of continuing anesthesia with a well-fitting supraglottic airway device, assessed using a visual analogue scale (0-100; 0 completely unacceptable; 100 completely acceptable), was 90 [22.5]. Preoperative patient consent regarding the use of a supraglottic airway device for surgery in the event of failed intubation would affect the decision making of 40% of anaesthetists surveyed. Conclusion. These results demonstrate that a significant body of anesthetists with a subspecialty interest in obstetric anesthesia in the UK would not always wake up the patient and would continue with anesthesia and surgery with a supraglottic airway device in this setting.

View details for DOI 10.1155/2015/192315

View details for PubMedID 25821464

View details for DOI 10.1016/j.ijoa.2014.07.003

View details for PubMedID 25433574

Abstract

Enhanced recovery, in part, aims to reduce postoperative gastrointestinal dysfunction (PGID). Acquired - or established- vagal dysfunction may contribute to PGID, even for surgery not involving the gastrointestinal tract. However, direct evidence for this is lacking. We hypothesized that chewing gum reduces morbidity (including PGID) by preserving efferent vagal neural activity postoperatively after elective orthopaedic surgery.In a two-centre randomized controlled trial (n=106), we explored whether patients randomized to prescribed chewing gum for five days postoperatively sustained less morbidity (primary outcome, defined by the Postoperative Morbidity Survey), PGID and faster time to become morbidity free (secondary outcomes). In a subset of patients (n=38), cardiac parasympathetic activity was measured by serial Holter monitoring and assessed using time and frequency domain analyses.Between September 2011 and April 2014, 106 patients were randomized to chewing gum or control. The primary clinical outcome did not differ between groups, with similar morbidity occurring between patients randomized to control (26/30) and chewing gum (21/28; absolute risk reduction (ARR):13% (95%C I:- 6-32); P=0.26). However, chewing gum reduced PGID (ARR:20% (95% CI: 1-38); P=0.049). Chewing gum reduced time to become morbidity-free (relative risk (RR): 1.62 (95% CI: 1.02-2.58); P=0.04) and was associated with a higher proportion of parasympathetic activity contributing to heart rate variability (11% (95% CI: 1-20); P=0.03).Chewing gum did not alter overall morbidity, but reduced PGID. These data show for the first time that prescription of sham feeding preserves vagal activity in surgery not directly involving the gastrointestinal tract.ISRCTN20301599.

View details for DOI 10.1093/bja/aev283

View details for PubMedID 26323293

Abstract

The objectives of this work were (i) to characterize the pharmacokinetics of cefazolin in pregnant women undergoing elective cesarean delivery and in their neonates; (ii) to assess cefazolin transplacental transmission; (iii) to evaluate the dosing and timing of preoperative, prophylactic administration of cefazolin to pregnant women; and (iv) to investigate the impact of maternal dosing on therapeutic duration and exposure in newborns. Twenty women received 1 g of cefazolin preoperatively. Plasma concentrations of total cefazolin were analyzed from maternal blood samples taken before, during, and after delivery; umbilical cord blood samples obtained at delivery; and neonatal blood samples collected 24 h after birth. The distribution volume of cefazolin was 9.44 liters/h. The values for pre- and postdelivery clearance were 7.18 and 4.12 liters/h, respectively. Computer simulations revealed that the probability of maintaining free cefazolin concentrations in plasma above 8 mg/liter during scheduled caesarean surgery was <50% in the cord blood when cefazolin was administered in doses of <2 g or when it was administered <1 h before delivery. Therapeutic concentrations of cefazolin persisted in neonates >5 h after birth. Cefazolin clearance increases during pregnancy, and larger doses are recommended for surgical prophylaxis in pregnant women to obtain the same antibacterial effect as in nonpregnant patients. Cefazolin has a longer half-life in neonates than in adults. Maternal administration of up to 2 g of cefazolin is effective and produces exposure within clinically approved limits in neonates.

View details for DOI 10.1128/AAC.02613-13

View details for Web of Science ID 000338776900064

Abstract

The objectives of this work were (i) to characterize the pharmacokinetics of cefazolin in pregnant women undergoing elective cesarean delivery and in their neonates; (ii) to assess cefazolin transplacental transmission; (iii) to evaluate the dosing and timing of preoperative, prophylactic administration of cefazolin to pregnant women; and (iv) to investigate the impact of maternal dosing on therapeutic duration and exposure in newborns. Twenty women received 1 g of cefazolin preoperatively. Plasma concentrations of total cefazolin were analyzed from maternal blood samples taken before, during, and after delivery; umbilical cord blood samples obtained at delivery; and neonatal blood samples collected 24 h after birth. The distribution volume of cefazolin was 9.44 liters/h. The values for pre- and postdelivery clearance were 7.18 and 4.12 liters/h, respectively. Computer simulations revealed that the probability of maintaining free cefazolin concentrations in plasma above 8 mg/liter during scheduled caesarean surgery was <50% in the cord blood when cefazolin was administered in doses of <2 g or when it was administered <1 h before delivery. Therapeutic concentrations of cefazolin persisted in neonates >5 h after birth. Cefazolin clearance increases during pregnancy, and larger doses are recommended for surgical prophylaxis in pregnant women to obtain the same antibacterial effect as in nonpregnant patients. Cefazolin has a longer half-life in neonates than in adults. Maternal administration of up to 2 g of cefazolin is effective and produces exposure within clinically approved limits in neonates.

View details for DOI 10.1128/AAC.02613-13

View details for PubMedID 24733461

View details for DOI 10.1213/ANE.0000000000000114

View details for PubMedID 24651247

Abstract

Explanatory mechanisms for the association between poor exercise capacity and infections following surgery are underexplored. We hypothesized that aerobic fitness-assessed by cardiopulmonary exercise testing (CPET)-would be associated with circulating inflammatory markers, as quantified by the neutrophil-lymphocyte ratio (NLR) and monocyte subsets. The association between cardiopulmonary reserve and inflammation was tested by multivariable regression analysis with covariates including anaerobic threshold (AT) and malignancy. In a first cohort of 240 colorectal patients, AT was identified as the sole factor associated with higher NLR (P = 0.03) and absolute and relative lymphopenia (P = 0.01). Preoperative leukocyte subsets and monocyte CD14(+) expression (downregulated by endotoxin and indicative of chronic inflammation) were also assessed in two further cohorts of age-matched elective gastrointestinal and orthopaedic surgical patients. Monocyte CD14(+) expression was lower in gastrointestinal patients (n = 43) compared to age-matched orthopaedic patients (n = 31). The circulating CD14(+)CD16(-) monocyte subset was reduced in patients with low cardiopulmonary reserve. Poor exercise capacity in patients without a diagnosis of heart failure is independently associated with markers of inflammation. These observations suggest that preoperative inflammation associated with impaired cardiorespiratory performance may contribute to the pathophysiology of postoperative outcome.

View details for PubMedID 25061264

View details for PubMedCentralID PMC4098894

Abstract

Myocardial injury after noncardiac surgery (MINS) was defined as prognostically relevant myocardial injury due to ischemia that occurs during or within 30 days after noncardiac surgery. The study's four objectives were to determine the diagnostic criteria, characteristics, predictors, and 30-day outcomes of MINS.In this international, prospective cohort study of 15,065 patients aged 45 yr or older who underwent in-patient noncardiac surgery, troponin T was measured during the first 3 postoperative days. Patients with a troponin T level of 0.04 ng/ml or greater (elevated "abnormal" laboratory threshold) were assessed for ischemic features (i.e., ischemic symptoms and electrocardiography findings). Patients adjudicated as having a nonischemic troponin elevation (e.g., sepsis) were excluded. To establish diagnostic criteria for MINS, the authors used Cox regression analyses in which the dependent variable was 30-day mortality (260 deaths) and independent variables included preoperative variables, perioperative complications, and potential MINS diagnostic criteria.An elevated troponin after noncardiac surgery, irrespective of the presence of an ischemic feature, independently predicted 30-day mortality. Therefore, the authors' diagnostic criterion for MINS was a peak troponin T level of 0.03 ng/ml or greater judged due to myocardial ischemia. MINS was an independent predictor of 30-day mortality (adjusted hazard ratio, 3.87; 95% CI, 2.96-5.08) and had the highest population-attributable risk (34.0%, 95% CI, 26.6-41.5) of the perioperative complications. Twelve hundred patients (8.0%) suffered MINS, and 58.2% of these patients would not have fulfilled the universal definition of myocardial infarction. Only 15.8% of patients with MINS experienced an ischemic symptom.Among adults undergoing noncardiac surgery, MINS is common and associated with substantial mortality.

View details for DOI 10.1097/ALN.0000000000000113

View details for PubMedID 24534856

View details for DOI 10.1016/j.ijoa.2014.05.010

View details for PubMedID 25201314

View details for DOI 10.1111/anae.12866

View details for PubMedID 25219491

Abstract

This retrospective, descriptive study aimed to assess hematologic testing practices in 100 patients with preeclampsia undergoing neuraxial blockade (NB). Prior to NB, platelet (PLT) count was performed in 61 (98%) of 62 women in labor and in 37 (97%) of 38 women undergoing cesarean delivery (CD). No patients had a pre-NB PLT count <70 10(9)/L. Pre-NB tests for prothrombin time (PT) and activated partial thromboplastin time (APTT) were less common and varied among laboring patients (15 [24%] of 62) and patients prior to CD (18 [47%] of 38). Prior to NB, PT and APTT values were within normal limits in all patients. The time intervals between laboratory testing and NB ranged from <2 to >12 hours. The lack of consistency in pre-NB coagulation testing and the variable time intervals between laboratory tests and NB may be due to a lack of consensus among anesthesiologists for determining "safe" hemostatic conditions for NB placement in patients with preeclampsia.

View details for DOI 10.1177/1076029612441860

View details for PubMedID 22531481

Abstract

The influence that different concentrations of labour epidural local anesthetic have on assisted vaginal delivery (AVD) and many obstetric outcomes and side effects is uncertain. The purpose of this meta-analysis was to determine whether local anesthetics utilized at low concentrations (LCs) during labour are associated with a decreased incidence of AVD when compared with high concentrations (HCs).We searched PubMed, Ovid EMBASE, Ovid MEDLINE, CINAHL, Scopus, clinicaltrials.gov, and Cochrane databases for randomized controlled trials of labouring patients that compared LCs (defined as 0.1% epidural bupivacaine or 0.17% ropivacaine) of epidural local anesthetic with HCs for maintenance of analgesia. The primary outcome was AVD and secondary outcomes included Cesarean delivery, duration of labour, analgesia, side effects (nausea and vomiting, motor block, hypotension, pruritus, and urinary retention), and neonatal outcomes. The odds ratios (OR) or weighted mean differences (WMD) and 95% confidence intervals (CI) were calculated using random effects modelling. An OR < 1 or a WMD < 0 favoured LCs.Eleven studies met our criteria (eight bupivacaine and three ropivacaine studies), providing 1,145 patients in the LCs group and 852 patients in the HCs group for analysis of the primary outcome. Low concentrations were associated with a reduction in the incidence of AVD (OR = 0.70; 95% CI 0.56 to 0.86; P < 0.001). There was no difference in the incidence of Cesarean delivery (OR 1.05; 95% CI 0.82 to 1.33; P = 0.7). The LCs group had less motor block (OR 3.9; 95% CI 1.59 to 9.55; P = 0.003), greater ambulation (OR 2.8; 95% CI 1.1 to 7.14; P = 0.03), less urinary retention (OR 0.42; 95% CI 0.23 to 0.73; P = 0.002), and a shorter second stage of labour (WMD -14.03; 95% CI -27.52 to -0.55; P = 0.04) compared with the HCs group. There were no differences between groups in pain scores, maternal nausea and vomiting, hypotension, fetal heart rate abnormalities, five-minute Apgar scores, and need for neonatal resuscitation. One-minute Apgar scores < 7 favoured the HCs group (OR 1.53; 95% CI 1.07 to 2.21; P = 0.02), and there was more pruritus in the LCs group (OR 3.36; 95% CI 1.00 to 11.31; P = 0.05).When compared with HCs of local anesthetics, the use of LCs for labour epidural analgesia reduces the incidence of AVD. This may be due to a reduction in the amount of local anesthetic used and the subsequent decrease in motor blockade. We therefore recommend the use of LCs of local anesthetics for epidural analgesia to optimize obstetric outcome.

View details for DOI 10.1007/s12630-013-9981-z

View details for Web of Science ID 000323340700002

View details for PubMedID 23925722

Abstract

BACKGROUND:In this study, we sought to determine whether neuraxial anesthesia to facilitate external cephalic version (ECV) increased delivery costs for breech fetal presentation.METHODS:Using a computer cost model, which considers possible outcomes and probability uncertainties at the same time, we estimated total expected delivery costs for breech presentation managed by a trial of ECV with and without neuraxial anesthesia.RESULTS:From published studies, the average probability of successful ECV with neuraxial anesthesia was 60% (with individual studies ranging from 44% to 87%) compared with 38% (with individual studies ranging from 31% to 58%) without neuraxial anesthesia. The mean expected total delivery costs, including the cost of attempting/performing ECV with anesthesia, equaled $8931 (2.5th-97.5th percentile prediction interval $8541-$9252). The cost was $9207 (2.5th-97.5th percentile prediction interval $8896-$9419) if ECV was attempted/performed without anesthesia. The expected mean incremental difference between the total cost of delivery that includes ECV with anesthesia and ECV without anesthesia was $-276 (2.5th-97.5th percentile prediction interval $-720 to $112).CONCLUSION:The total cost of delivery in women with breech presentation may be decreased (up to $720) or increased (up to $112) if ECV is attempted/performed with neuraxial anesthesia compared with ECV without neuraxial anesthesia. Increased ECV success with neuraxial anesthesia and the subsequent reduction in breech cesarean delivery rate offset the costs of providing anesthesia to facilitate ECV.

View details for DOI 10.1213/ANE.0b013e31828e5bc7

View details for PubMedID 23592608

View details for PubMedID 24159644

Abstract

BACKGROUND:In this study, we sought to determine whether neuraxial anesthesia to facilitate external cephalic version (ECV) increased delivery costs for breech fetal presentation.METHODS:Using a computer cost model, which considers possible outcomes and probability uncertainties at the same time, we estimated total expected delivery costs for breech presentation managed by a trial of ECV with and without neuraxial anesthesia.RESULTS:From published studies, the average probability of successful ECV with neuraxial anesthesia was 60% (with individual studies ranging from 44% to 87%) compared with 38% (with individual studies ranging from 31% to 58%) without neuraxial anesthesia. The mean expected total delivery costs, including the cost of attempting/performing ECV with anesthesia, equaled $8931 (2.5th-97.5th percentile prediction interval $8541-$9252). The cost was $9207 (2.5th-97.5th percentile prediction interval $8896-$9419) if ECV was attempted/performed without anesthesia. The expected mean incremental difference between the total cost of delivery that includes ECV with anesthesia and ECV without anesthesia was $-276 (2.5th-97.5th percentile prediction interval $-720 to $112).CONCLUSION:The total cost of delivery in women with breech presentation may be decreased (up to $720) or increased (up to $112) if ECV is attempted/performed with neuraxial anesthesia compared with ECV without neuraxial anesthesia. Increased ECV success with neuraxial anesthesia and the subsequent reduction in breech cesarean delivery rate offset the costs of providing anesthesia to facilitate ECV.

View details for DOI 10.1213/ANE.0b013e31828e5bc7

View details for Web of Science ID 000326512300025

Abstract

Management of the peripartum patient is a challenging aspect of critical care that requires consideration of both the physiological changes associated with pregnancy as well as the well-being of the foetus. In the UK, for every maternal death, approximately 118 near-miss events or severe acute maternal morbidities (SAMMs) occur. While a dedicated anaesthetic cover is usually provided on larger labour wards in the UK and US, a close communication with intensive care and other medical specialties must still be maintained. Medical outreach teams and early warning scores may help facilitate the early identification of clinical deterioration and prompt treatment. Ultimately level of care is allocated according to the clinical need, not the location, which may be a designated room, a normal labour room or a recovery area. Specialist obstetric units that provide high-dependency care facilities show lower rates of maternal transfer to critical care units and improved continuity of care before and after labour. The benefits of obstetric high-dependency units (HDUs) are likely to be determined by a number of logistic aspects of the hospital organisation, including hospital size and available resources. There remains a striking contrast in the burden of maternal mortality and morbidity and intensive care unit (ICU) resources between high- and low-income countries. The countries with the highest maternal mortality rates have the lowest number of ICU beds per capita. In under-resourced countries, patients admitted to ICUs tend to have higher illness severity scores, suggesting delayed admission to the ICU. The appropriate training of midwives is essential for successful HDUs located within labour wards.

View details for DOI 10.1016/j.bpobgyn.2013.07.005

View details for PubMedID 23972289

Abstract

We present anesthetic management using a continuous spinal anesthesia (CSA) technique in a patient with placenta increta who underwent elective Cesarean hysterectomy with massive postpartum hemorrhage.A 34-yr-old parturient (G3P2) was scheduled for Cesarean delivery and possible hysterectomy at 35(+3) weeks due to suspected placenta accreta. Her body mass index was 21kgm(-2) and she had a reassuring airway. Inadvertent dural puncture occurred during combined spinal-epidural (CSE) placement, and a decision was made to thread the epidural catheter and utilize a CSA technique. Following delivery of a healthy infant, morbid adherence of the placenta to the myometrium was confirmed, and a supracervical hysterectomy was performed. Eight litres of blood loss occurred postpartum requiring resuscitation with crystalloid 3,800mL, colloid 1,500mL, red blood cells 16 units, fresh frozen plasma 16 units, platelets 4 units, and cryoprecipitate 1 unit. The patient developed pulmonary edema requiring conversion to general anesthesia. The patient's cardiovascular status was stable throughout surgery, and her lungs were mechanically ventilated for 18 hr postoperatively in the intensive care unit. The intrathecal catheter was removed 24 hr after placement. She developed no adverse neurological sequelae and reported no postdural puncture headache. The pathology report confirmed placenta increta.A CSA technique may be a viable option in the event of inadvertent dural puncture during planned CSE or epidural placement in patients with a reassuring airway undergoing Cesarean delivery. Although a catheter-based neuraxial technique is appropriate for Cesarean hysterectomy for abnormal placentation, conversion to general anesthesia may be required in the event of massive perioperative hemorrhage and fluid resuscitation.

View details for DOI 10.1007/s12630-012-9681-0

View details for PubMedID 22395824

Abstract

We present a case of a parturient with babesiosis and Lyme disease who was scheduled for elective caesarean section. The caesarean section was performed under spinal anaesthesia, and the patient had a coronary artery dissection 4 days postoperatively. Neuraxial anaesthesia and possible mechanisms for the coronary artery dissection in a patient with babesiosis and Lyme disease are discussed.

View details for DOI 10.1111/j.1365-2044.2011.06941.x

View details for Web of Science ID 000299158200012

View details for PubMedID 22251109

Abstract

Reduced muscle strength- commonly characterized by decreased handgrip strength compared to population norms- is associated with numerous untoward outcomes. Preoperative handgrip strength is a potentially attractive real-time, non-invasive, cheap and easy-to-perform "bedside" assessment tool. Using systematic review procedure, we investigated whether preoperative handgrip strength was associated with postoperative outcomes in adults undergoing surgery.PRISMA and MOOSE consensus guidelines for reporting systematic reviews were followed. MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Clinical Trials (1980-2010) were systematically searched by two independent reviewers. The selection criteria were limited to include studies of preoperative handgrip strength in human adults undergoing non-emergency, cardiac and non-cardiac surgery. Study procedural quality was analysed using the Newcastle-Ottawa Quality Assessment score. The outcomes assessed were postoperative morbidity, mortality and hospital stay.Nineteen clinical studies (17 prospective; 4 in urgent surgery) comprising 2194 patients were identified between1980-2010. Impaired handgrip strength and postoperative morbidity were defined inconsistently between studies. Only 2 studies explicitly ensured investigators collecting postoperative outcomes data were blinded to preoperative handgrip strength test results. The heterogeneity of study design used and the diversity of surgical procedures precluded formal meta-analysis. Despite the moderate quality of these observational studies, lower handgrip strength was associated with increased morbidity (n = 10 studies), mortality (n = 2/5 studies) and length of hospital stay (n = 3/7 studies).Impaired preoperative handgrip strength may be associated with poorer postoperative outcomes, but further work exploring its predictive power is warranted using prospectively acquired, objectively defined measures of postoperative morbidity.

View details for PubMedID 22251661

Abstract

Evidence suggests that some aspects of schizophrenia can be induced in healthy volunteers through acute administration of the non-competitive NMDA-receptor antagonist, ketamine. In probabilistic inference tasks, patients with schizophrenia have been shown to 'jump to conclusions' (JTC) when asked to make a decision. We aimed to test whether healthy participants receiving ketamine would adopt a JTC response pattern resembling that of patients. The paradigmatic task used to investigate JTC has been the 'urn' task, where participants are shown a sequence of beads drawn from one of two 'urns', each containing coloured beads in different proportions. Participants make a decision when they think they know the urn from which beads are being drawn. We compared performance on the urn task between controls receiving acute ketamine or placebo with that of patients with schizophrenia and another group of controls matched to the patient group. Patients were shown to exhibit a JTC response pattern relative to their matched controls, whereas JTC was not evident in controls receiving ketamine relative to placebo. Ketamine does not appear to promote JTC in healthy controls, suggesting that ketamine does not affect probabilistic inferences.

View details for DOI 10.1177/0269881111435252

View details for PubMedID 22389244

View details for PubMedCentralID PMC3546628

View details for PubMedID 23124413

Abstract

Tracheal intubation constitutes a routine part of anaesthetic practice both in the operating theatre as well as in the care of critically ill patients. The procedure is estimated to be performed 13-20 million times annually in the United States alone. There has been a recent renewal of interest in the morbidity associated with endotracheal tube cuff overinflation, particularly regarding the rationale and requirement for endotracheal tube cuff monitoring intra-operatively.

View details for PubMedID 22165491

Abstract

The desire to decrease the number of cesarean deliveries has renewed interest in external cephalic version. The rationale for using neuraxial blockade to facilitate external cephalic version is to provide abdominal muscular relaxation and reduce patient discomfort during the procedure, so permitting successful repositioning of the fetus to a cephalic presentation. This review systematically examined the current evidence to determine the safety and efficacy of neuraxial anesthesia or analgesia when used for external cephalic version.A systematic literature review of studies that examined success rates of external cephalic version with neuraxial anesthesia was performed. Published articles written in English between 1945 and 2010 were identified using the Medline, Cochrane, EMBASE and Web of Sciences databases.Six, randomized controlled studies were identified. Neuraxial blockade significantly improved the success rate in four of these six studies. A further six non-randomized studies were identified, of which four studies with control groups found that neuraxial blockade increased the success rate of external cephalic version. Despite over 850 patients being included in the 12 studies reviewed, placental abruption was reported in only one patient with a neuraxial block, compared with two in the control groups. The incidence of non-reassuring fetal heart rate requiring cesarean delivery in the anesthesia groups was 0.44% (95% CI 0.15-1.32).Neuraxial blockade improved the likelihood of success during external cephalic version, although the dosing regimen that provides optimal conditions for successful version is unclear. Anesthetic rather than analgesic doses of local anesthetics may improve success. The findings suggest that neuraxial blockade does not compromise maternal or fetal safety during external cephalic version.

View details for DOI 10.1016/j.ijoa.2011.07.001

View details for Web of Science ID 000297087100006

View details for PubMedID 21925869

View details for PubMedID 21537230

Abstract

An anaesthetic preoperative assessment for all patients is the standard of care in UK hospitals. The Royal College of Anaesthetists (RCoA) 2009 guidelines state that a postoperative visit, within 24 hours following surgery, is recommended for patients only in certain circumstances. This article critiques these guidelines and explores factors which must be taken into consideration when deciding whether or not anaesthetists should routinely visit their patients after they leave the recovery area. We discuss the physiological rationale for performing a postoperative anaesthetic visit; the identification of post-operative morbidity including provision of adequate post-operative analgesia; patient benefits; limitations of performing postoperative review, and the implications that expanding anaesthetists' responsibilities as perioperative physicians has had upon anaesthetic training and service provision. Finally, this article offers an alternative model for deciding when to perform a post-anaesthetic visit.

View details for PubMedID 21560554

Abstract

Morphine is a drug commonly administered via the epidural or intrathecal route, and is regarded by many as the 'gold-standard' single-dose neuraxial opioid due to its postoperative analgesic efficacy and prolonged duration of action. However, respiratory depression is a recognized side effect of neuraxial morphine administered in the perioperative setting. We conducted an extensive review of articles published since 1945 that examine respiratory depression or failure associated with perioperative intrathecal or epidural morphine use. Respiratory depression was previously thought to result from the interaction of opioid in the cerebrospinal fluid with ventral medullary opioid receptors. More recently, the preBtzinger complex located in the medulla has been identified as the site responsible for the decrease in respiratory rate following systemic administration of opioids. Neurons in the preBtzinger complex expressing neurokinin-1 receptors are selectively inhibited by opioids, and therefore are the mediators of opioid-induced respiratory depression. Epidural, intrathecal and plasma pharmacokinetics of opioids are complex, vary between neuraxial compartments, and can even differ within the epidural space itself depending upon level of insertion. Caution should be exercised when prescribing systemic opioids (intravenous or oral) in addition to neuraxial morphine as this can compound the potential for early or delayed respiratory depression. There is a wide range of incidences for respiratory depression following neuraxial morphine in a perioperative setting. Disparity of definitions used for the diagnosis of respiratory depression in the literature precludes identification of the exact incidence of this rare event. The optimal neuraxial opioid dose is a balance between the conflicting demands of providing optimal analgesia while minimizing dose-related adverse effects. Dose-response studies show that neuraxial morphine appears to have an analgesic efficacy 'ceiling'. The optimal 'single-shot' intrathecal dose appears to be 0.075-0.15 mg and the ideal 'single-shot' epidural morphine dose is 2.5-3.75 mg. Analgesic efficacy studies have not been adequately powered to show differences in the incidence of clinically significant respiratory depression. Opioid antagonists such as naloxone to prevent or treat opioid-induced respiratory depression have a number of limitations. Researchers have recently focused on non-opioid drugs such as serotonin receptor agonists. Early evidence suggests that ampakine (-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid [AMPA]) receptor modulators may be effective at reducing opioid-induced respiratory depression while maintaining analgesia. Sodium/proton exchanger type 3 (NHE3) inhibitors, which act centrally on respiratory pathways, also warrant further study.

View details for PubMedID 21942973

View details for PubMedID 20944517

View details for DOI 10.1097/00003643-201006121-00742

View details for Web of Science ID 000209824000741

View details for DOI 10.12968/hmed.2010.71.11.79666

View details for PubMedID 21063267

View details for DOI 10.12968/hmed.2010.71.5.47924

View details for PubMedID 20448504

View details for DOI 10.12968/hmed.2010.71.Sup2.46506

View details for PubMedID 20220710

View details for DOI 10.12968/hmed.2010.71.2.46497

View details for PubMedID 20220706

Abstract

Obstructive sleep apnoea (OSA) has life threatening perioperative cardiorespiratory implications. As patients present to hospital for incidental surgery unaware of their condition, perioperative practitioners need a thorough knowledge of OSA to allow optimisation before theatre. Elective cases should be delayed for investigation and treatment if OSA is suspected. In theatre cardiorespiratory problems should be managed by a senior anaesthetist and a perioperative team alert to the risk of post-operative hypoxia.

View details for DOI 10.1177/175045890901901104

View details for PubMedID 20041627

Abstract

Over the last 20 years, there has been a large increase in the proportion of caesarean sections (Brown and Russell, 1995) which are performed under regional rather than general anaesthesia. A bilateral sensory block from the T4 dermatome (nipple level) to the sacral nerve roots (perineum) is necessary.

View details for DOI 10.12968/hmed.2009.70.10.44637

View details for PubMedID 19966715

View details for DOI 10.12968/hmed.2008.69.9.31058

View details for PubMedID 18819313

View details for DOI 10.12968/hmed.2008.69.3.28763

View details for PubMedID 18422234

View details for DOI 10.12968/hmed.2008.69.2.28365

View details for PubMedID 18386748

Abstract

Hospital-acquired infections are commonly resistant to antibiotics and cause substantial morbidity and mortality in susceptible populations. Although there is no direct contact between the anaesthetic machine's controls and the patient, there is considerable potential for colonising organisms to be carried between the anaesthetic machine and the patient on the anaesthetist's hands. We performed two cross-sectional studies of bacterial contamination on anaesthetic machines before and after a simple intervention. Without warning, during theatre sessions, bacterial cultures were obtained from anaesthetic equipment. A new departmental policy of cleaning anaesthetic equipment with detergent wipes between cases was then introduced. Six weeks later, again without warning, a further set of cultures was taken. There was significant reduction in the proportion of cultures containing pathogenic bacteria (from 14/78 cultures (18%; 95% CI 9.4-26.5%) before the intervention to 5/77 cultures (6%; 95% CI 1.0-12%) after the intervention (p = 0.03)). The intervention was quick, easy and enthusiastically taken up by the majority of staff. We conclude that cleaning of anaesthetic equipment between cases should become routine practice.

View details for DOI 10.1111/j.1365-2044.2007.05261.x

View details for PubMedID 17991263