Clinical Focus

  • Pediatric Anesthesia
  • Pediatric cardiac anesthesia
  • Pediatric Anesthesiology

Academic Appointments

Professional Education

  • Board Certification: The Royal College of Anaesthetists, Anesthesia (2007)
  • Residency: South East Scotland School of Anaesthesia (2007) Scotland
  • Fellowship: Westmead Children's Hospital (2006) Australia
  • Residency: South East Scotland School of Anaesthesia (2001) Scotland
  • Residency: South Manchester NHS Trust (1999) UK
  • Residency: Trafford General Hospital (1999) UK
  • Residency: St John's Hospital at Howden (1998) UK
  • Internship: South Manchester NHS Trust (1997) UK
  • Medical Education: Edinburgh University (1997) UK

Clinical Trials

  • Effects of Different Tidal Volume Ventilation Strategies on Fontan Flow and Hemodynamics Not Recruiting

    In patients with Fontan circulation blood is not pumped to the lungs from a ventricle. Instead the superior vena cava and inferior vena cava is connected to the pulmonary artery and blood flow to the lungs occurs passively along this Fontan pathway. This passive blood flow to the lungs occurs best when the patient is breathing on their own (spontaneous ventilation). However for certain surgeries and procedures patients need to have an endotracheal tube inserted and need to be muscle relaxed and receive positive pressure ventilation. Prior studies have shown that positive pressure ventilation can reduce blood flow to the lungs and consequently blood returning to the heart resulting in less blood pumped out to the rest of the body (cardiac output). The purpose of this study is to investigate if changing the volume of the positive pressure ventilation (tidal volume) affects blood flow to the lungs and cardiac output in patients with Fontan circulation.

    Stanford is currently not accepting patients for this trial. For more information, please contact Manchula Navaratnam, MD, 650-714-6014.

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  • The Hemodynamic Effects of Vasopressin in Patients With Fontan Physiology Not Recruiting

    The goal of this study is to evaluate if vasopressin can elevate systemic arterial blood pressures without having a significant effect on pulmonary arterial pressures. Because patients who have undergone Fontan procedures rely on low pressures across the pulmonary vascular bed to maintain cardiac output, vasoactive agents that concomitantly increase systemic and pulmonary pressures may have a deleterious effect in this specific patient population. Hypothesis: In patients with Fontan physiology, vasopressin will increase systemic BP by 20% above baseline, without increasing the transpulmonary gradient.

    Stanford is currently not accepting patients for this trial. For more information, please contact Study team, 847-219-5569.

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All Publications

  • Intraoperative and Postoperative Hemodynamic Predictors of Acute Kidney Injury in Pediatric Heart Transplant Recipients. Journal of pediatric intensive care Hollander, S. A., Chung, S., Reddy, S., Zook, N., Yang, J., Vella, T., Navaratnam, M., Price, E., Sutherland, S. M., Algaze, C. A. 2024; 13 (1): 37-45


    Acute kidney injury (AKI) is common after pediatric heart transplantation (HT) and is associated with inferior patient outcomes. Hemodynamic risk factors for pediatric heart transplant recipients who experience AKI are not well described. We performed a retrospective review of 99 pediatric heart transplant patients at Lucile Packard Children's Hospital Stanford from January 1, 2015, to December 31, 2019, in which clinical and demographic characteristics, intraoperative perfusion data, and hemodynamic measurements in the first 48 postoperative hours were analyzed as risk factors for severe AKI (Kidney Disease: Improving Global Outcomes [KDIGO] stage ≥ 2). Univariate analysis was conducted using Fisher's exact test, Chi-square test, and the Wilcoxon rank-sum test, as appropriate. Multivariable analysis was conducted using logistic regression. Thirty-five patients (35%) experienced severe AKI which was associated with lower intraoperative cardiac index ( p  = 0.001), higher hematocrit ( p  < 0.001), lower body temperature ( p  < 0.001), lower renal near-infrared spectroscopy ( p  = 0.001), lower postoperative mean arterial blood pressure (MAP: p  = 0.001), and higher central venous pressure (CVP; p  < 0.001). In multivariable analysis, postoperative CVP >12 mm Hg (odds ratio [OR] = 4.27; 95% confidence interval [CI]: 1.48-12.3, p  = 0.007) and MAP <65 mm Hg (OR = 4.9; 95% CI: 1.07-22.5, p  = 0.04) were associated with early severe AKI. Children with severe AKI experienced longer ventilator, intensive care, and posttransplant hospital days and inferior survival ( p  = 0.01). Lower MAP and higher CVP are associated with severe AKI in pediatric HT recipients. Patients, who experienced AKI, experienced increased intensive care unit (ICU) morbidity and inferior survival. These data may guide the development of perioperative renal protective management strategies to reduce AKI incidence and improve patient outcomes.

    View details for DOI 10.1055/s-0041-1736336

    View details for PubMedID 38571984

    View details for PubMedCentralID PMC10987224

  • Acute Hemodynamics in the Fontan Circulation: Open-Label Study of Vasopressin. Pediatric critical care medicine : a journal of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies Adamson, G. T., Yu, J., Ramamoorthy, C., Peng, L. F., Taylor, A., Lennig, M., Schmidt, A. R., Feinstein, J. A., Navaratnam, M. 2023


    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 0.4±0.4 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 0.04±0.03 (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 (0.1±0.3, 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

  • Coming Soon to an OR Near You: a Child with a Ventricular Assist Device CURRENT ANESTHESIOLOGY REPORTS Kleiman, Z., Navaratnam, M. 2023
  • In Response. Anesthesia and analgesia Navaratnam, M., Boothroyd, D., Zhang, S., Williams, G. D. 2023; 136 (6): e40-e41

    View details for DOI 10.1213/ANE.0000000000006449

    View details for PubMedID 37205823

  • Multidisciplinary Stroke Pathway for Children Supported with Ventricular Assist Devices. ASAIO journal (American Society for Artificial Internal Organs : 1992) Lee, S., Ryan, K. R., Murray, J., Chen, S., Grant, G. A., Wilkins, S., Yarlagadda, V. V., Wintermark, M., Dodd, R., Rosenthal, D., Teuteburg, J., Navaratnam, M., Lee, J., Jordan, L. C., Almond, C. S. 2023


    Mechanical circulatory support (MCS), including ventricular assist device (VAD) support, is a leading cause of stroke in children; however, existing pediatric stroke recommendations do not apply to many pediatric VAD patients. We sought to develop a multidisciplinary pathway to improve timely and effective acute stroke care and examine the early performance of the pathway in expediting stroke care. Stakeholders from pediatric heart failure, cardiac intensive care, neurology, interventional radiology, neuroradiology, neurosurgery, pharmacy, and adult VAD care convened at Stanford University in August 2017 to discuss the challenges of providing high-quality acute stroke care to children on VAD support, and to develop multidisciplinary acute stroke pathways. Stakeholders identified multiple barriers to providing timely acute stroke care to pediatric VAD patients. These include delayed recognition of stroke, and lack of clarity related to the optimal imaging technique, when to emergently reverse antithrombotic therapy (AT), pediatric indications for thrombectomy and cranial decompression, and strategies to avoid unnecessary serial CTS. Four stroke pathways were created including evaluation and management of the pediatric patient with (1) an acute neurologic change before an imaging diagnosis; (2) an arterial ischemic stroke (AIS); (3) an intracerebral hemorrhage (ICH); and (4) a subdural hematoma (SDH). With the implementation of the stroke pathway, the median time-to-first-CT image decreased by 43 minutes from 66 to 23 minutes (P < 0.001) while the proportion with a CT within 30 minutes increased from 0% to 67% (P < 0.001). Despite a variety of challenges, multidisciplinary consensus can be achieved on a rapid stroke management pathway for children on VAD support that addresses important barriers to timely stroke care. Although too few stoke events occurred to differentiate clinical outcomes, the time-to-first-CT image was significantly shorter after pathway implementation.

    View details for DOI 10.1097/MAT.0000000000001822

    View details for PubMedID 36917842

  • Activated 4-Factor Prothrombin Complex Concentrate as a Hemostatic Adjunct for Neonatal Cardiac Surgery: A Propensity Score-Matched Cohort Study. Anesthesia and analgesia Navaratnam, M., Mendoza, J. M., Zhang, S., Boothroyd, D., Maeda, K., Kamra, K., Williams, G. D. 2022


    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

  • ISHLT consensus statement: Perioperative management of patients with pulmonary hypertension and right heart failure undergoing surgery. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation McGlothlin, D. P., Granton, J., Klepetko, W., Beghetti, M., Rosenzweig, E. B., Corris, P. A., Horn, E., Kanwar, M. K., McRae, K., Roman, A., Tedford, R., Badagliacca, R., Bartolome, S., Benza, R., Caccamo, M., Cogswell, R., Dewachter, C., Donahoe, L., Fadel, E., Farber, H. W., Feinstein, J., Franco, V., Frantz, R., Gatzoulis, M., Hwa Anne Goh, C., Guazzi, M., Hansmann, G., Hastings, S., Heerdt, P. M., Hemnes, A., Herpain, A., Hsu, C., Kerr, K., Kolaitis, N. A., Kukreja, J., Madani, M., McCluskey, S., McCulloch, M., Moser, B., Navaratnam, M., Radegran, G., Reimer, C., Savale, L., Shlobin, O. A., Svetlichnaya, J., Swetz, K., Tashjian, J., Thenappan, T., Vizza, C. D., West, S., Zuckerman, W., Zuckermann, A., De Marco, T. 2022; 41 (9): 1135-1194


    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

  • Intraoperative epicardial echocardiography or transoesophageal echocardiography in CHD: how much does it matter? Cardiology in the young Stauffer, K. J., Brabender, J., Reddy, C. D., Selamet Tierney, E. S., Lopez, L., Maeda, K., Navaratnam, M., Punn, R. 2022: 1-8


    BACKGROUND: Intraoperative imaging determines the integrity of surgical repairs. Transoesophageal echocardiography represents standard care for intraoperative imaging in CHD. However, some conditions preclude its use, and epicardial echocardiography is used alternatively. Minimal literature exists on the impact of epicardial echocardiography versus transoesophageal echocardiography. We aimed to evaluate accuracy between the two modalities and hypothesised higher imaging error rates for epicardial echocardiography.METHODS: We retrospectively reviewed all epicardial echocardiograms performed over 16 years and compared them to an age- and procedure-matched, randomly selected transoesophageal echocardiography cohort. We detected un- or misidentified cardiac lesions during the intraoperative imaging and evaluated patient outcomes. Data are presented as a median with a range, or a number with percentages, with comparisons by Wilcoxon two-sample test and Fisher's exact test.RESULTS: Totally, 413 patients comprised the epicardial echocardiography group with 295 transoesophageal echocardiography matches. Rates of imaging discrepancies, re-operation, and incision infection were similar. About 13% of epicardial echocardiography patients had imaging discrepancies versus 16% for transoesophageal (p = 0.2352), the former also had smaller body sizes (p < 0.0001) and more genetic abnormalities (33% versus 19%, p < 0.0001). Death/mechanical support occurred more frequently in epicardial echocardiography patients (16% versus 6%, p < 0.0001), while hospitalisations were longer (25 versus 19 days, p = 0.0003).CONCLUSIONS: Diagnostic accuracy was similar between patients undergoing epicardial echocardiography and transoesophageal echocardiography, while rates of death and mechanical support were increased in this inherently higher risk patient population. Epicardial echocardiography provides a reasonable alternative when transoesophageal echocardiography is not feasible.

    View details for DOI 10.1017/S1047951122001536

    View details for PubMedID 35747949

  • Impact of a clinical pathway on acute kidney injury in patients undergoing heart transplant. Pediatric transplantation Algaze, C. A., Margetson, T. D., Sutherland, S. M., Kwiatkowski, D. M., Maeda, K., Navaratnam, M., Samreth, S. P., Price, E. P., Zook, N. B., Yang, J. K., Hollander, S. A. 2021: e14166


    BACKGROUND: To evaluate the impact of a clinical pathway on the incidence and severity of acute kidney injury in patients undergoing heart transplant.METHODS: This was a 2.5-year retrospective evaluation using 3years of historical controls within a cardiac intensive care unit in an academic children's hospital. Patients undergoing heart transplant between May 27, 2014, and April 5, 2017 (pre-pathway) and May 1, 2017, and November 30, 2019 (pathway) were included. The clinical pathway focused on supporting renal perfusion through hemodynamic management, avoiding or delaying nephrotoxic medications, and providing pharmacoprophylaxis against AKI.RESULTS: There were 57 consecutive patients included. There was an unadjusted 20% reduction in incidence of any acute kidney injury (p=.05) and a 17% reduction in Stage 2/3 acute kidney injury (p=.09). In multivariable adjusted analysis, avoidance of Stage 2/3 acute kidney injury was independently associated with the clinical pathway era (AOR -1.3 [95% CI -2.5 to -0.2]; p=.03), achieving a central venous pressure of or less than 12mmHg (AOR -1.3 [95% CI -2.4 to -0.2]; p=.03) and mean arterial pressure above 60mmHg (AOR -1.6 [95% CI -3.1 to -0.01]; p=.05) in the first 48h post-transplant, and older age at transplant (AOR - 0.2 [95% CI -0.2 to -0.06]; p=.002).CONCLUSIONS: This report describes a renal protection clinical pathway associated with a reduction in perioperative acute kidney injury in patients undergoing heart transplant and highlights the importance of normalizing perioperative central venous pressure and mean arterial blood pressure to support optimal renal perfusion.

    View details for DOI 10.1111/petr.14166

    View details for PubMedID 34727417

  • Intraoperative and Postoperative Hemodynamic Predictors of Acute Kidney Injury in Pediatric Heart Transplant Recipients JOURNAL OF PEDIATRIC INTENSIVE CARE Hollander, S. A., Chung, S., Reddy, S., Zook, N., Yang, J., Vella, T., Navaratnam, M., Price, E., Sutherland, S. M., Algaze, C. A. 2021
  • Neurosurgical intervention in children with ventricular assist devices: A single center case series review. Paediatric anaesthesia Yu, J., Murray, J., Ramamoorthy, C., Chen, S., Lee, S., Ryan, K., Maeda, K., Navaratnam, M. 2021


    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

  • Impact of Modified Anesthesia Management for Pediatric Patients With Williams Syndrome. Journal of cardiothoracic and vascular anesthesia Schmidt, A. R., Collins, R. T., Adusumelli, Y., Ramamoorthy, C., Weng, Y., MacMillen, K. L., Navaratnam, M. 2021


    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

  • Adverse Events Associated with Cardiac Catheterization in Children Supported with Ventricular Assist Devices. ASAIO journal (American Society for Artificial Internal Organs : 1992) Power, A., Navaratnam, M., Murray, J. M., Peng, L. F., Rosenthal, D. N., Dykes, J. C., Yarlagadda, V. V., Maeda, K., Almond, C. S., Chen, S. 2021


    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

  • Comparison of combined heart‒liver vs heart-only transplantation in pediatric and young adult Fontan recipients. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation Sganga, D., Hollander, S. A., Vaikunth, S., Haeffele, C., Bensen, R., Navaratnam, M., McDonald, N., Profita, E., Maeda, K., Concepcion, W., Bernstein, D., Chen, S. 2020


    BACKGROUND: Indications for a heart‒liver transplantation (HLT) for Fontan recipients are not well defined. We compared listing characteristics, post-operative complications, and post-transplant outcomes of Fontan recipients who underwent HLT with those of patients who underwent heart-only transplantation (HT). We hypothesized that patients who underwent HLT have increased post-operative complications but superior survival outcomes compared with patients who underwent HT.METHODS: We performed a retrospective review of Fontan recipients who underwent HLT or HT at a single institution. Characteristics at the time of listing, including the extent of liver disease determined by laboratory, imaging, and biopsy data, were compared. Post-operative complications were assessed, and the Kaplan‒Meier survival method was used to compare post-transplant survival. Univariate regression analyses were performed to identify the risk factors for increased mortality and morbidity among patients who underwent HT.RESULTS: A total of 47 patients (9 for HLT, 38 for HT) were included. Patients who underwent HLT were older, were more likely to be on dual inotrope therapy, and had evidence of worse liver disease. Whereas ischemic time was longer for the group who underwent HLT, post-operative complications were similar. Over a median post-transplant follow-up of 17 (interquartile range: 5-52) months, overall mortality for the cohort was 17%; only 1 patient who underwent HLT died (11%) vs 7 patients who underwent HT (18%) (p = 0.64). Among patients who underwent HT, cirrhosis on pre-transplant imaging was associated with worse outcomes.CONCLUSIONS: Despite greater inotrope need and more severe liver disease at the time of listing, Fontan recipients undergoing HLT have post-transplant outcomes comparable with those of patients undergoing HT. HLT may offer a survival benefit for Fontan recipients with liver disease.

    View details for DOI 10.1016/j.healun.2020.12.008

    View details for PubMedID 33485775

  • Management of a Pediatric Patient With a Left Ventricular Assist Device and Symptomatic Acquired von Willebrand Syndrome Presenting for Orthotopic Heart Transplant. Seminars in cardiothoracic and vascular anesthesia Flannery, K. M., Kamra, K., Maeda, K., Shuttleworth, P., Almond, C., Navaratnam, M. 2020: 1089253220949386


    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

  • Pectoral Nerve Blocks Decrease Postoperative Pain and Opioid Use After Pacemaker or Implantable Cardioverter-Defibrillator Placement in Children. Heart rhythm Yang, J. K., Char, D. S., Motonaga, K. S., Navaratnam, M., Dubin, A. M., Trela, A., Hanisch, D. G., McFadyen, G., Chubb, H., Goodyer, W., Ceresnak, S. R. 2020


    BACKGROUND: Pectoral nerve blocks (PECS) can reduce intra-procedural anesthetic requirements and postoperative pain. Little is known on the utility of PECS in reducing pain and narcotic use after pacemaker (PM) or implantable cardioverter defibrillator (ICD) placement in children.OBJECTIVE: To determine whether PECS can decrease postoperative pain and opioid use after PM or ICD placement in children.METHODS: A single center, retrospective review of pediatric patients undergoing transvenous PM or ICD placement between 2015-2020 was performed. Patients with recent cardiothoracic surgery or neurologic/developmental deficits were excluded. Demographics, procedural variables, postoperative pain, and postoperative opioid usage were compared between patients who underwent PECS and those who underwent conventional local anesthetic (CONTROL).RESULTS: A total of 74 patients underwent PM or ICD placement with 20 patients (27%) undergoing PECS. There were no differences between PECS and CONTROL with regard to age, weight, gender, type of device placed, presence of congenital heart disease, type of anesthesia, procedural time or complication rates. Patients who underwent PECS had lower pain scores at 1, 2, 6, 18, and 24-hours compared to CONTROL. PECS patients had a lower mean cumulative pain score [PECS 1.5 (95%-CI 0.8-2.2) vs CONTROL 3.1 (95%-CI 2.7-3.5); P<0.001] and lower total opioid use [PECS 6.0 MME/m2 (95%-CI 3.4-8.6) vs CONTROL 15.0 MME/m2 (95%-CI 11.8-18.2); P=0.001] over the 24-hours post-implant.CONCLUSIONS: Pectoralis nerve blocks reduce postoperative pain scores and lower total opioid usage after ICD or PM placement. PECS should be considered at the time of transvenous device placement in children.

    View details for DOI 10.1016/j.hrthm.2020.03.009

    View details for PubMedID 32201270

  • Evolution of Single Ventricular Assist Device Support for the Failing Bi-directional Glenn Patient. The Annals of thoracic surgery Maeda, K., Nasirov, T., Yarlagadda, V., Hollander, S. A., Navaratnam, M., Rosenthal, D. N., Dykes, J. C., Kaufman, B. D., Almond, C. S., Reinhartz, O., Murray, J., Chen, S. 2020


    BACKGROUND: Given poor outcomes, strategies to improve ventricular assist device (VAD) for single ventricle (SV) patients with bi-directional Glenn (BDG) palliation is needed.METHODS: Retrospective review of our institutional experience with VAD support for BDG patients from April 2011 to January 2019. Surgical strategies, complications and causes of death are described. Survival to transplant for various strategies are compared.RESULTS: Seven patients with BDG (weights 5.6-28.8 kg, ages 7 months - 11 years) underwent VAD implantation. Three patients received Berlin Heart EXCOR, 2 received Heartware HVADs and 2 patients received paracorporeal continuous flow devices. Four patients underwent ventricular inflow cannulation, and 3 underwent atrial inflow cannulation. At the time of VAD implant, the BDG was left intact in 3 patients, taken down in 3 patients, and created de novo in 1 patient. Over a total of 420 VAD support days, 2 patients survived to heart transplant; one with Heartware ventricular cannulation and intact BDG (after 174 days), and another with Berlin Heart atrial cannulation and BDG take-down (after 72 days). There were 3 deaths within 2 weeks of VAD implant (2 due to respiratory failure, 1 due to infection) and 2 deaths after 30 days due to strokes.CONCLUSIONS: The surgical strategy and postoperative management of VAD with BDG are still evolving. Successful support can be achieved with 1) both pulsatile and continuous flow pumps, 2) atrial or ventricular cannulation, and 3) with or without BDG take-down. Surgical strategy should be determined by individual patient anatomy, physiology and condition.

    View details for DOI 10.1016/j.athoracsur.2019.12.088

    View details for PubMedID 32151575

  • The use of prothrombin complex concentrate as a warfarin reversal agent in pediatric patients undergoing orthotopic heart transplantation. Paediatric anaesthesia Sisti, D., Williams, G. D., Ding, V., Long, J., Maeda, K., Chen, S., Navaratnam, M. 2020


    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

  • Bridge to Transplant with Ventricular Assist Device Support in Pediatric Patients with Single Ventricle Heart Disease ASAIO JOURNAL Chen, S., Rosenthal, D. N., Murray, J., Dykes, J. C., Almond, C. S., Yarlagadda, V. V., Wright, G., Navaratnam, M., Reinhartz, O., Maeda, K. 2020; 66 (2): 205–11
  • Peri-operative right ventricular dysfunction—the anesthesiologist’s view. Cardiovasc Diagnosis Therapies Navaratnam, M., DiNardo, J. A. 2020; 10 (5): 1725-1734

    View details for DOI 10.21037/cdt-20-426

    View details for PubMedCentralID PMC7666948

  • Pediatric ventricular assist devices: Bridge to a new era of perioperative care PEDIATRIC ANESTHESIA Navaratnam, M., Maeda, K., Hollander, S. A. 2019; 29 (5): 506–18

    View details for DOI 10.1111/pan.13609

    View details for Web of Science ID 000468217100016

  • Preoperative Laboratory Studies for Pediatric Cardiac Surgery Patients: A Multi-Institutional Perspective ANESTHESIA AND ANALGESIA Jones, S. E., Jooste, E. H., Gottlieb, E. A., Schwartz, J., Goswami, D., Gautam, N. K., Benkwitz, C., Downey, L. A., Guzzetta, N. A., Zabala, L., Latham, G. J., Faraoni, D., Navaratnam, M., Wise-Faberowski, L., McDaniel, M., Spurrier, E., Machovec, K. A. 2019; 128 (5): 1051–54
  • Preoperative Laboratory Studies for Pediatric Cardiac Surgery Patients: A Multi-Institutional Perspective. Anesthesia and analgesia Jones, S. E., Jooste, E. H., Gottlieb, E. A., Schwartz, J., Goswami, D., Gautam, N. K., Benkwitz, C., Downey, L. A., Guzzetta, N. A., Zabala, L., Latham, G. J., Faraoni, D., Navaratnam, M., Wise-Faberowski, L., McDaniel, M., Spurrier, E., Machovec, K. A. 2019

    View details for PubMedID 30896598

  • Bridge to Transplant with Ventricular Assist Device Support in Pediatric Patients with Single Ventricle Heart Disease. ASAIO journal (American Society for Artificial Internal Organs : 1992) Chen, S., Rosenthal, D. N., Murray, J., Dykes, J. C., Almond, C. S., Yarlagadda, V. V., Wright, G., Navaratnam, M., Reinhartz, O., Maeda, K. 2019


    Ventricular assist device (VAD) support for children with single ventricle (SV) heart disease remains challenging. We performed a single-center retrospective review of SV patients on VAD support and examined survival to transplant using the Kaplan-Meier method. Patients transplanted were compared with those who died on support. Between 2009 and 2017, there were 14 SV patients with 1,112 patient-days of VAD support. Stages of palliation included pre-Glenn (n = 5), Glenn (n = 5), and Fontan (n = 4). Eight patients (57%) were successfully bridged to transplant at a median 107 days. Deaths occurred early (n = 6, median 16 days) and in smaller patients (10.1 vs. 28.3 kg, P = 0.04). All Fontan patients survived to transplant, whereas only 20% of Glenn patients survived to transplant. Adverse events occurred in 79% (n = 11). Five patients met hospital discharge criteria, with two patients (one pre-Glenn, one Glenn) discharged and transplanted after 219 and 174 days of VAD support. All transplanted patients were discharged at a median 21 days posttransplant. SV patients in various stages of palliation can be successfully bridged to transplant with VAD support. With use of intracorporeal continuous-flow devices, longer-term support and hospital discharge are possible.

    View details for PubMedID 30864969

  • Pediatric ventricular assist devices: Bridge to a new era of peri-operative care. Paediatric anaesthesia Navaratnam, M., Maeda, K., Hollander, S. A. 2019


    Pediatric ventricular assist devices (VADs) are evolving as a standard therapy for end stage heart failure in children. Major recent developments include the increased use of continuous flow (CF) devices in children and increased experience with congenital heart disease (CHD) and outpatient management. In the current and future era anesthesiologists will encounter more children presenting for VAD implantation, subsequent procedures and heart transplantation. Successful peri-operative management requires an understanding of the interaction between the patient's physiology and the device and a framework to troubleshoot problems. This review focuses on CF devices, VAD support for CHD and peri-operative management of pulsatile and CF devices in the pediatric population. This article is protected by copyright. All rights reserved.

    View details for PubMedID 30758099

  • Epoprostenol Therapy for a Pediatric Patient With Subacute Heparin-Induced Thrombocytopenia and a Ventricular Assist Device Undergoing Heart Transplant: A Case Report A & A PRACTICE Navaratnam, M., Williams, G. D., Shuttleworth, P., Almond, C., Maeda, K. 2018; 11 (12): 329–31


    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

  • Bilateral automatized intermittent bolus erector spinae plane analgesic blocks for sternotomy in a cardiac patient who underwent cardiopulmonary bypass: A new era of Cardiac Regional Anesthesia. Journal of clinical anesthesia Tsui, B. C., Navaratnam, M. n., Boltz, G. n., Maeda, K. n., Caruso, T. J. 2018; 48: 9–10

    View details for DOI 10.1016/j.jclinane.2018.04.005

    View details for PubMedID 29684728

  • LVOT-VTI is a Useful Indicator of Low Ventricular Function in Young Patients. Pediatric cardiology Navaratnam, M., Punn, R., Ramamoorthy, C., Tacy, T. A. 2017


    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 1 year 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. 0.18 m; p < 0.0012). The mean CW-LVOT-VTI was significantly lower in DCM (0.20 vs. 0.24 m; 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 <0.17 m (AUC = 0.73; p < 0.0001) and CW-LVOT-VTI <0.22 m (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 1 year.

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

    View details for PubMedID 28534242

  • Perioperative management of pediatric en-bloc combined heart-liver transplants: a case series review. Paediatric anaesthesia Navaratnam, M., Ng, A., Williams, G. D., Maeda, K., Mendoza, J. M., Concepcion, W., Hollander, S. A., Ramamoorthy, C. 2016; 26 (10): 976-986


    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

  • Surgical Reconstruction of Tracheal Stenosis in Conjunction With Congenital Heart Defects Basic Science Forum of the 58th Annual Meeting of the Southern-Thoracic-Surgical-Association Mainwaring, R. D., Shillingford, M., Davies, R., Koltai, P., Navaratnam, M., Reddy, V. M., Hanley, F. L. ELSEVIER SCIENCE INC. 2012: 1266–73


    Surgical reconstruction is the primary method of treating airway obstruction in children. Tracheal stenosis is frequently associated with congenital heart defects, which may further complicate the overall management strategy. The purpose of this study was to review our experience with surgical reconstruction of airway obstruction in conjunction with congenital heart defects.This was a retrospective review of our surgical experience with tracheal stenosis from February 2003 to August 2011. Twenty-seven patients were identified in our database. Six patients had isolated, congenital tracheal stenosis, and 21 had tracheal stenosis in association with congenital heart defects. There were two identifiable subgroups. Thirteen patients had airway stenoses identified concurrently with congenital heart defects and underwent combined repair. The second group comprised 8 patients who had previous correction of their congenital heart defects and experienced delayed presentation of tracheal (n = 6) or bronchial (n = 2) obstruction.The median age at surgery was 9 months. There were 2 postoperative deaths, both in children with single ventricle. The median duration of follow-up for the entire cohort of 25 surviving patients was 4 years. None of the patients have required reoperations on the trachea; 5 have had minor reinterventions.The data demonstrate that tracheal obstruction is frequently found in conjunction with congenital heart defects. Nearly one third of our patients had delayed presentation of airway obstruction that was identified subsequent to previous congenital heart defect repair. Tracheal reconstructive techniques were effective regardless of the cause of the airway obstruction.

    View details for DOI 10.1016/j.athoracsur.2011.12.063

    View details for PubMedID 22381444

  • Pediatric pacemakers and ICDs: how to optimize perioperative care PEDIATRIC ANESTHESIA Navaratnam, M., Dubin, A. 2011; 21 (5): 512-521


    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