Manchula Navaratnam, MD

Abstract

OBJECTIVE: To describe the acute hemodynamic effect of vasopressin on the Fontan circulation, including systemic and pulmonary pressures and resistances, left atrial pressure, and cardiac index.DESIGN: Prospective, open-label, nonrandomized study (NCT04463394).SETTING: Cardiac catheterization laboratory at Lucile Packard Children's Hospital, Stanford.PATIENTS: Patients 3-50 years old with a Fontan circulation who were referred to the cardiac catheterization laboratory for hemodynamic assessment and/or intervention.INTERVENTIONS: A 0.03 U/kg IV (maximum dose 1 unit) bolus of vasopressin was administered over 5 minutes, followed by a maintenance infusion of 0.3 mU/kg/min (maximum dose 0.03 U/min).MEASUREMENTS AND MAIN RESULTS: Comprehensive cardiac catheterization measurements before and after vasopressin administration. Measurements included pulmonary artery, atrial, and systemic arterial pressures, oxygen saturations, and systemic and pulmonary flows and resistances. There were 28 patients studied. Median age was 13.5 (9.1, 17) years, and 16 (57%) patients had a single or dominant right ventricle. Following vasopressin administration, systolic blood pressure and systemic vascular resistance (SVR) increased by 17.5 (13.0, 22.8) mm Hg (Z value -4.6, p < 0.001) and 3.8 (1.8, 7.5) Wood Units (Z value -4.6, p < 0.001), respectively. The pulmonary vascular resistance (PVR) decreased by 0.40.4 WU (t statistic 6.2, p < 0.001), and the left atrial pressure increased by 1.0 (0.0, 2.0) mm Hg (Z value -3.5, p < 0.001). The PVR:SVR decreased by 0.040.03 (t statistic 8.1, p < 0.001). Neither the pulmonary artery pressure (median difference 0.0 [-1.0, 1.0], Z value -0.4, p = 0.69) nor cardiac index (0.10.3, t statistic -1.4, p = 0.18) changed significantly. There were no adverse events.CONCLUSIONS: In Fontan patients undergoing cardiac catheterization, vasopressin administration resulted in a significant increase in systolic blood pressure, SVR, and left atrial pressure, decrease in PVR, and no change in cardiac index or pulmonary artery pressure. These findings suggest that in Fontan patients vasopressin may be an option for treating systemic hypotension during sedation or general anesthesia.

View details for DOI 10.1097/PCC.0000000000003326

View details for PubMedID 37462430

Abstract

BACKGROUND: Prothrombin complex concentrates are an emerging "off-label" therapy to augment hemostasis after cardiopulmonary bypass (CPB), but data supporting their use for neonatal cardiac surgery are limited.METHODS: We retrospectively reviewed neonates undergoing open heart surgery with first-time sternotomy between May 2014 and December 2018 from a hospital electronic health record database. Neonates who received activated 4-factor prothrombin complex concentrate (a4FPCC) after CPB were propensity score matched (PSM) to neonates who did not receive a4FPCC (control group). The primary efficacy outcome was total volume (mL/kg) of blood products transfused after CPB, including the first 24 hours on the cardiovascular intensive care unit (CVICU). The primary safety outcome was the incidence of 7- and 30-day postoperative thromboembolism. Secondary outcomes included 24 hours postoperative chest tube output, time to extubation, duration of CVICU stay, duration of hospital stay, 30-day mortality, and incidence of acute kidney injury on postoperative day 3. We used linear regression modeling on PSM data for the primary efficacy outcome. For the primary safety outcome, we tested for differences using McNemar test on PSM data. For secondary outcomes, we used linear regression, Fisher exact test, or survival analyses as appropriate, with false discovery rate-adjusted P values.RESULTS: A total of 165 neonates were included in the final data analysis: 86 in the control group and 79 in the a4FPCC group. After PSM, there were 43 patients in the control group and 43 in the a4FPCC group. We found a statistically significant difference in mean total blood products transfused for the a4FPCC group (47.5 mL/kg) compared with the control group (63.7 mL/kg) for PSM patients (adjusted difference, 15.3; 95% CI, 29.4-1.3; P = .032). We did not find a statistically significant difference in 7- or 30-day thromboembolic rate, postoperative chest tube output, time to extubation, incidence of postoperative acute kidney injury (AKI), or 30-day mortality between the groups. The a4FPCC group had a significantly longer length of intensive care unit stay (32.9 vs 13.3 days; adjusted P = .049) and hospital stay (44.6 vs 24.1 days; adjusted P = .049) compared with the control group.CONCLUSIONS: We found that the use of a4FPCC as a hemostatic adjunct for post-CPB bleeding in neonatal cardiac surgery was associated with a decrease in mean total blood products transfused after CPB without an increased rate of 7- or 30-day postoperative thromboembolism. Our findings suggest that a4FPCCs can be considered as part of a hemostasis pathway for refractory bleeding in neonatal cardiac surgery.

View details for DOI 10.1213/ANE.0000000000006294

View details for PubMedID 36729967

Abstract

Pulmonary hypertension (PH) is a risk factor for morbidity and mortality in patients undergoing surgery and anesthesia. This document represents the first international consensus statement for the perioperative management of patients with pulmonary hypertension and right heart failure. It includes recommendations for managing patients with PH being considered for surgery, including preoperative risk assessment, planning, intra- and postoperative monitoring and management strategies that can improve outcomes in this vulnerable population. This is a comprehensive document that includes common perioperative patient populations and surgical procedures with unique considerations.

View details for DOI 10.1016/j.healun.2022.06.013

View details for PubMedID 36123001

Abstract

BACKGROUND: The incidence of neurological complications related to ventricular assist devices (VAD) remains high and includes life-threatening conditions such as intracranial hemorrhage or ischemic stroke. Although no definitive management guidelines exist, operative interventions may be required for major neurological injuries.AIMS: This case series describes the perioperative management of children at a single center who underwent neurosurgical procedures for major intracranial bleeds or ischemic strokes whilst on VAD support.METHODS: A database review identified all pediatric VAD patients who underwent a neurosurgical procedure for an intracranial hemorrhage or ischemic stroke from April 2014 to January 2020. Data regarding patient characteristics, preoperative medical management, intraoperative anesthetic management, and postoperative outcomes were collected using retrospective chart review.RESULTS: Ninety VADs were implanted in 78 patients. Five neurosurgical interventions were performed: 4 for intracranial hemorrhages and 1 for an ischemic stroke. All 4 patients with hemorrhages were receiving anticoagulation at the time of their event and the 3 patients on warfarin received emergent reversal with prothrombin concentrate complex and vitamin K. Three patients also received pre-procedural platelet transfusions. Two of the 5 procedures were emergent bedside external ventricular drain placements and 3 were surgical operations. All 3 patients who underwent operative procedures received invasive hemodynamic monitoring and were supported with a combination of inotropes and afterload reduction. One patient required a massive blood product transfusion. The 2 patients who underwent external ventricular drain placement had no further surgical interventions and died from the severity of their neurological injuries. All 3 patients who underwent operative procedures survived to transplantation and discharge home.CONCLUSIONS: Perioperative concerns for the anesthesiologist include VAD hemodynamic management, bleeding, VAD thrombosis, and prevention of secondary brain injury. A systematic, multidisciplinary approach to management is paramount to attain favorable outcomes.

View details for DOI 10.1111/pan.14287

View details for PubMedID 34478592

Abstract

OBJECTIVE: This study compared the percent change in systolic blood pressure and the incidence of adverse cardiac events (ACEs; defined as cardiac arrest, cardiopulmonary resuscitation, arrhythmias, or ST-segment changes) during anesthesia induction in patients with Williams syndrome (WS) before and after implementation of a perioperative management strategy.DESIGN: Retrospective observational cohort study.SETTING: Single quaternary academic referral center.PARTICIPANTS: The authors reviewed the records of all children with WS at the authors' institution who underwent general anesthesia for cardiac catheterization, diagnostic imaging, or any type of surgery between November 2008 and August 2019. The authors identified 142 patients with WS, 48 of whom underwent 118 general anesthesia administrations. A historic group (HG) was compared with the intervention group (IG).INTERVENTIONS: Change in perioperative management (three-stage risk stratification: preoperative intravenous hydration, intravenous anesthesia induction, and early use of vasoactives).MEASUREMENTS AND MAIN RESULTS: The authors determined event rates within 60 minutes of anesthesia induction. Standardized mean difference (SMD) was calculated (SMD >0.2 suggests clinically meaningful difference). Sixty-seven general anesthesia encounters were recorded in the HG (mean age, 4.8 years; mean weight, 16.3 kg) and 51 in the IG (mean age, 6.0 years; mean weight, 18.2 kg). The change in systolic blood pressure was -17.5% (-30.0, -5.0) in the HG versus -9% (-18.0, 5.0) in the IG (p=0.015; SMD=0.419), and the incidence of ACEs was 6% in the HG and 2% in the IG (p=0.542; SMD=0.207).CONCLUSIONS: Preoperative risk stratification, preoperative intravenous hydration, intravenous induction, and early use of continuous vasoactives resulted in greater hemodynamic stability, with a 2% incidence of ACEs.

View details for DOI 10.1053/j.jvca.2021.04.019

View details for PubMedID 34049787

Abstract

Children on ventricular assist device (VAD) support can present several unique challenges, including small patient size, univentricular or biventricular congenital heart disease (1V- or 2V-CHD) and need for biventricular VAD (BiVAD) support. While cardiac catheterization can provide valuable information, it is an invasive procedure with inherent risks. We sought to evaluate the safety of catheterization in pediatric patients on VAD support. We performed a retrospective review of patients on VAD support who underwent catheterization at Lucile Packard Children's Hospital between January 1, 2014 and September 1, 2019. Using definitions adapted from Pedimacs, adverse events (AEs) after catheterization were identified, including arrhythmia; major bleeding or acute kidney injury within 24 hours; respiratory failure persisting at 24 hours; and stroke, pericardial effusion, device malfunction, bacteremia or death within 7 days. AEs were categorized as related or unrelated to catheterization. Sixty procedures were performed on 39 patients. Underlying diagnoses were dilated cardiomyopathy (48%), 1V-CHD (35%), 2V-CHD (8%), and other (8%). Devices were implantable continuous flow (72%), paracorporeal pulsatile (18%) and paracorporeal continuous flow (10%). Catheterizations were performed on patients in the ICU (60%), on inotropic support (42%), with deteriorating clinical status (37%) and on BiVAD support (12%). There were 9 AEs possibly related to catheterization including 6 episodes of respiratory failure, 2 major bleeding events, and 1 procedural arrhythmia. AE occurrence was associated with ICU status (P = 0.01), BiVAD support (P = 0.04) and procedural indication to evaluate worsening clinical status (P = 0.04). Despite high medical acuity, catheterization can be performed with an acceptable AE profile in children on VAD support.

View details for DOI 10.1097/MAT.0000000000001627

View details for PubMedID 34967779

Abstract

We present the successful perioperative management of an 11-year-old patient presenting for heart transplant with a left ventricular assist device, symptomatic acquired von Willebrand syndrome, and recent preoperative intracranial hemorrhage. A brief review of the pathophysiology of acquired von Willebrand syndrome is included. As the number of pediatric patients supported with ventricular assist devices continues to increase, the management of symptomatic acquired von Willebrand syndrome during the perioperative period is an important consideration for anesthesiologists.

View details for DOI 10.1177/1089253220949386

View details for PubMedID 32772894

Abstract

BACKGROUND: Patients supported with a ventricular assist device are predisposed to severe bleeding at the time of orthotopic heart transplant due to several risk factors including anticoagulation with vitamin K antagonists. Kcentra, a four-factor prothrombin complex concentrate has been approved by the FDA for warfarin reversal in adults prior to urgent surgery. There is a lack of published data on the preoperative use of four-factor prothrombin complex concentrates in pediatric patients undergoing cardiac surgery.METHODS: This is a single center retrospective analysis of pediatric patients with a continuous flow ventricular assist device who underwent heart transplant, comparing patients who received Kcentra for anticoagulation reversal with a historical patient cohort who did not. Consecutive patients from January 2013 to December 2017 were analyzed. The primary outcome was volume of blood product transfusion prior to cardiopulmonary bypass initiation. Secondary outcomes include blood product transfusion after cardiopulmonary bypass intraoperatively and up to 24 hours postoperatively, chest tube output within 24 hours of surgery, time to extubation, incidence of thromboembolism, and post-transplant length of stay.RESULTS: From 2013 to 2017, 31 patients with continuous flow ventricular assist devices underwent heart transplant, with 27 patients included in the analysis. Fifteen patients received Kcentra compared with 12 patients who received fresh frozen plasma for anticoagulation reversal. Compared with the control group, patients who received Kcentra had less packed red blood cells, fresh frozen plasma, and platelets transfused prior to cardiopulmonary bypass initiation. The Kcentra group also received less packed red blood cells on bypass and less packed red blood cells after cardiopulmonary bypass termination. There were no differences in chest tube output, time to extubation, intensive care unit length of stay or overall hospital length of stay. Neither group had thromboembolic complications detected during the first 7 postoperative days.CONCLUSION: This small retrospective study indicates that preoperative warfarin reversal with Kcentra reduces blood product exposure in pediatric patients with ventricular assist devices undergoing heart transplant.

View details for DOI 10.1111/pan.13839

View details for PubMedID 32037665

View details for DOI 10.21037/cdt-20-426

View details for PubMedCentralID PMC7666948

View details for DOI 10.1111/pan.13609

View details for Web of Science ID 000468217100016

Abstract

Concerns remain regarding the use of direct thrombin inhibitors for cardiopulmonary bypass anticoagulation in pediatric patients with heparin-induced thrombocytopenia undergoing complex cardiac surgery. We describe the safe and effective use of epoprostenol sodium as an alternative therapy before heparin exposure for a pediatric patient with subacute heparin-induced thrombocytopenia and a ventricular assist device undergoing heart transplant.

View details for PubMedID 29985837

Abstract

Left ventricular outflow tract velocity time integral (LVOT-VTI), a Doppler-derived measure of stroke distance, is used as a surrogate marker of cardiac function in adults. LVOT-VTI is easily obtained, independent of ventricular geometry and wall motion abnormalities. We investigated the relationship between LVOT-VTI and conventional measures of function in young patients by comparing controls to children with dilated cardiomyopathy (DCM). Sixty-two healthy and 52 DCM patients over 1year were studied retrospectively. The average pulsed (PW) and continuous wave (CW) LVOT-VTIs from apical views were measured from three cycles. Body surface area (BSA) and Ejection fraction (EF) were obtained. We compared LVOT-VTIs between study and control groups and assessed BSA's impact on LVOT-VTI. The entire cohort was classified into three levels of LV function which were compared. We determined LVOT-VTI cutoff values that indicated an EF<50%. The mean PW-LVOT-VTI in the DCM group was significantly lower than that of the normal group (0.15 vs. 0.18m; p<0.0012). The mean CW-LVOT-VTI was significantly lower in DCM (0.20 vs. 0.24m; p<0.0001). There was no impact of BSA on LVOT-VTI except when comparing BSA and CW-LVOT-VTI in the normal group. There was a positive relationship between LVOT-VTI and EF for PW (Rs=0.29, p=0.0022) and CW (Rs=0.22, p=0.0364) and a difference in mean LVOT-VTI between EF groups (p<0.0001). ROC analysis demonstrated that PW-LVOT-VTI<0.17m (AUC=0.73; p<0.0001) and CW-LVOT-VTI<0.22m (AUC=0.76; p<0.0001) was associated with EF<50%. This study indicates that LVOT-VTI can be a useful alternative measure of LV performance in children over 1year.

View details for DOI 10.1007/s00246-017-1630-9

View details for PubMedID 28534242

Abstract

Combined heart and liver transplantation (CHLT) in the pediatric population involves a complex group of patients, many of whom have palliated congenital heart disease (CHD) involving single ventricle physiology.The purpose of this study was to describe the perioperative management of pediatric patients undergoing CHLT at a single institution and to identify management strategies that may be used to optimize perioperative care.We did a retrospective database review of all patients receiving CHLT at a children's hospital between 2006 and 2014. Information collected included preoperative characteristics, intraoperative management, blood transfusions, and postoperative morbidity and mortality.Five pediatric CHLTs were performed over an 8-year period. All patients had a history of complex CHD with multiple sternotomies, three of whom had failing Fontan physiology. Patient age ranged from 7 to 23 years and weight from 29.5 to 68.5 kg. All CHLTs were performed using an en-bloc technique where both the donor heart and liver were implanted together on cardiopulmonary bypass (CPB). The median operating room time was 14.25 h, median CPB time was 3.58 h, and median donor ischemia time was 4.13 h. Patients separated from CPB on dopamine, epinephrine, and milrinone infusions and two required inhaled nitric oxide. All patients received a massive intraoperative blood transfusion post CPB with amounts ranging from one to three times the patient's estimated blood volume. The patient who required the most transfusions was in decompensated heart and liver failure preoperatively. Four of the five patients received an antifibrinolytic agent as well as a procoagulant (prothrombin complex concentrate or recombinant activated Factor VII) to assist with hemostasis. There were no 30-day thromboembolic events detected. Postoperatively the median length of mechanical ventilation, ICU stay and stay to hospital discharge was 4, 8, and 37 days, respectively. All patients are alive and free from allograft rejection at this time.Combined heart and liver transplantation in the pediatric population involves a complex group of patients with unique perioperative challenges. Successful management starts with thorough preoperative planning and communication and involves strategies to deal with massive intraoperative hemorrhage and coagulopathy in addition to protecting and supporting the transplanted heart and liver and meticulous surgical technique. An integrated multidisciplinary team approach is the cornerstone for successful outcomes.

View details for DOI 10.1111/pan.12950

View details for PubMedID 27402424

Abstract

An increasing number of pediatric patients with permanent pacemakers and implantable cardioverter defibrillators (ICDs) require cardiac and noncardiac surgery. It is critical that the anesthesiologist caring for these patients understands the management of the device and the underlying heart disease. Children with these devices are more vulnerable to lead failure and inappropriate shocks compared with the adult population. Preoperative assessment and appropriate reprogramming of the device, in addition to minimizing sources of electromagnetic interference, are keystones in the perioperative care of these patients. Prior consultation with qualified programmers is recommended to enable timely optimization of the device. Magnets may be used in emergency situations but it is important to appreciate the limitations of magnet use on different models of pacemakers and ICDs. Safe and successful perioperative care is dependent upon a well-organized and coordinated multidisciplinary team approach.

View details for DOI 10.1111/j.1460-9592.2011.03562.x

View details for Web of Science ID 000289469500006

View details for PubMedID 21481077