Perfusion techniques for an 800 g premature neonate undergoing Arterial Switch Procedure for Transposition of the Great Arteries☠.

Early cardiac surgery in neonates and infants with congenital heart disease has been performed since the middle to late years of the twentieth century. To date, there are very few reports of successful congenital heart surgery using cardiopulmonary bypass (CPB) in premature babies less than 1000 g with serious congenital heart disease. Limited information is available in the literature describing perfusion techniques for this extremely fragile patient population. Miniaturization of the CPB circuit contributes to multiple factors that affect this population significantly. These factors include the reduction of patient-to-circuit ratios, volume of distribution of pharmacological agents, management of pressure gradients within the CPB system, and increased tactile control by the attending perfusionist. Careful management of the physiological environment of the patient is of utmost importance and can mitigate risks during CPB, including volume shifts into the interstitial space, electrolyte, and acid-base imbalance, and intracranial hemorrhage. We report perfusion techniques successfully utilized during the surgical repair of transposition of the great arteries for an 800 g, 28-week-old neonate. CPB techniques for the smallest and youngest patients may be executed safely when proper physical, chemical, and perfusion process adjustments are made and managed meticulously.

Evaluating variation in pre-operative evaluation and planning for children undergoing atrial or ventricular septal defect repair.

BACKGROUND: CHD care is resource-intensive. Unwarranted variation in care may increase cost and result in poorer health outcomes. We hypothesise that process variation exists within the pre-operative evaluation and planning process for children undergoing repair of atrial septal defect or ventricular septal defect and that substantial variation occurs in a small number of care points. METHODS: From interviews with staff of an integrated congenital heart centre, an initial process map was constructed. A retrospective chart review of patients with isolated surgical atrial septal defect and ventricular septal defect repair from 7/1/2018 through 11/1/2020 informed revisions of the process map. The map was assessed for points of consistency and variability. RESULTS: Thirty-two surgical atrial septal defect/ventricular septal defect repair patients were identified. Ten (31%) were reviewed by interventional cardiology before surgical review. Of these, 6(60%) had a failed catheter-based closure and 4 (40%) were deemed inappropriate for catheter-based closure. Thirty (94%) were reviewed in case conference, all attended surgical clinic, and none were admitted prior to surgery. The process map from interviews alone identified surgery rescheduling as a point of major variability; however, chart review revealed this was not as prominent a source of variability as pre-operative interventional cardiology review. CONCLUSIONS: Significant variation in the pre-operative evaluation and planning process for surgical atrial septal defect/ventricular septal defect patients was identified. If such process variation is widespread through CHD care, it may contribute to variations in outcome and cost previously documented within CHD surgery. Future research will focus on determining whether the variation is warranted or unwarranted, associated health outcomes and cost variation attributed to these variations in care processes.

Bradycardic Arrest in a Child with Complex Congenital Heart Disease Due to Sugammadex Administration.

The neuromuscular blocking drugs rocuronium and vecuronium are often used during general anesthesia. These drugs temporarily paralyze the patient and thus both facilitate placement of an endotracheal tube and prevent any patient movement during surgery. Reversal of neuromuscular blockade is necessary at the end of surgery to avoid postoperative weakness and adverse respiratory events in the recovery room. Neostigmine, the traditional reversal agent, may not completely restore muscle strength. Sugammadex is a reversal agent that is more effective and quicker acting than neostigmine. In adults, sugammadex administration has rarely been associated with bradycardia and cardiac arrest. In healthy children, the bradycardia that occurs after sugammadex administration is benign and does not require intervention. There is 1 case report of a 10- to 15-second bradycardic arrest after sugammadex administration to a 10-year-old child with heart disease. The present case report describes an 8-month-old child with complex congenital heart disease who experienced a 10-minute bradycardic arrest after the administration of sugammadex. Pediatric anesthesiologists should be aware that sugammadex administration to children with heart disease may cause hemodynamically significant bradycardia.

Outcomes of thoracic aortic interventions in Marfan syndrome in the state of Texas over 11 years.

OBJECTIVES: Marfan syndrome is a heritable connective tissue disorder with significant aortopathy and conveys substantial cardiovascular morbidity. This study characterizes the mortality and morbidities of thoracic aortic interventions (TAI) in the Marfan syndrome population in the state of Texas from 2009 to 2019. METHODS: A retrospective review of the Texas Inpatient Discharge Dataset from 1 January 2009 to 31 December 2019. Discharges from acute care hospitals with a Marfan syndrome diagnosis by the International Classification of Diseases 9/10 codes and a procedure code for TAI were analysed utilizing descriptive, univariate and multivariable regression statistics. RESULTS: There were 4641 Marfan syndrome discharges identified, of whom 644 (13.9%) underwent TAI. Thoracic or thoraco-abdominal aortic dissection or rupture was noted in 223 (34.6%). Thirty-three (5.1%) had a concomitant coronary artery intervention. There were 30 (4.7%) in-hospital mortalities, 126 (19.6%) diagnoses of acute renal failure (ARF), 52 (8.1%) had mechanical ventilation >96 h and the median length of stay was 10 [interquartile range (IQR) 7-16] days. After adjustment, concomitant coronary artery intervention was associated with in-hospital mortality [odds ratio (OR) 3.69 [IQR 1.15-11.90], P = 0.029] and ARF (OR 2.66 [IQR 1.19-5.94], P = 0.017). Aortic dissections/ruptures were associated with ARF (OR 1.73 [IQR 1.14-2.63], P = 0.010), ventilation >96 h (OR 2.19 [IQR 1.21-3.97], P = 0.010), and 15% longer length of stay (95% confidence interval 2.4-29.1%, P = 0.038). CONCLUSIONS: TAI are frequent among the hospitalized Marfan Syndrome population. Concomitant coronary intervention is associated with increased risk of death and aortic dissections/ruptures are associated with increased morbidity. The high prevalence of aortic dissections/ruptures points to a potential target for improving imaging surveillance, adherence to treatment guidelines and preventative management of Marfan syndrome aortopathy.

Trisomy 18: disparities of care and outcomes in the State of Texas between 2009 and 2019.

OBJECTIVE: To perform a statewide characteristics and outcomes analysis of the Trisomy 18 (T18) population and explore the potential impact of associated congenital heart disease (CHD) and congenital heart surgery. STUDY DESIGN: Retrospective review of the Texas Hospital Inpatient Discharge Public Use Data File between 2009 and 2019, analysing discharges of patients with T18 identified using ICD-9/10 codes. Discharges were linked to analyse patients. Demographic characteristics and available outcomes were evaluated. The population was divided into groups for comparison: patients with no documentation of CHD (T18NoCHD), patients with CHD without congenital heart surgery (T18CHD), and patients who underwent congenital heart surgery (T18CHS). RESULTS: One thousand one hundred fifty-six eligible patients were identified: 443 (38%) T18NoCHD, 669 (58%) T18CHD, and 44 (4%) T18CHS. T18CHS had a lower proportion of Hispanic patients (n = 9 (20.45%)) compared to T18CHD (n = 315 (47.09%)), and T18NoCHD (n = 219 (49.44%)) (p < 0.001 for both). Patients with Medicare/Medicaid insurance had a 0.42 odds ratio (95%CI: 0.20-0.86, p = 0.020) of undergoing congenital heart surgery compared to private insurance. T18CHS had a higher median total days in-hospital (47.5 [IQR: 12.25-113.25] vs. 9 [IQR: 3-24] and 2 [IQR: 1-5], p < 0.001); and a higher median number of admissions (n = 2 [IQR: 1-4]) vs. 1 [IQR: 1-2] and 1 [IQR: 1-1], (p < 0.001 for both). However, the post-operative median number of admissions for T18CHS was 0 [IQR: 0-2]. After the first month of life, T18CHS had freedom from in-hospital mortality similar to T18NoCHD and superior to T18CHD. CONCLUSIONS: Short-term outcomes for T18CHS patients are encouraging, suggesting a freedom from in-hospital mortality that resembles the T18NoCHD. The highlighted socio-economic differences between the groups warrant further investigation. Development of a prospective registry for T18 patients should be a priority for better understanding of longer-term outcomes.

Routine Perioperative Esmolol After Infant Tetralogy of Fallot Repair: Single-Center Retrospective Study of Hemodynamics.

OBJECTIVES: Currently, surgical repair of tetralogy of Fallot (TOF) is associated with an 1.1% 30-day mortality rate. Those with junctional ectopic tachycardia (JET) and restrictive right ventricular physiology have poorer outcomes. Routine postoperative adrenergic or inodilator therapy has been reported, while beta-blockade following cardiopulmonary bypass has not. This study evaluated routine perioperative treatment with esmolol in infants undergoing TOF repair. DESIGN: Retrospective chart review of the perioperative course following TOF repair. SETTING: Single-center case series describing perioperative management of TOF in a cardiac ICU. PATIENTS: This study reviewed all patients less than 18 months old who underwent TOF repair, excluding cases of TOF with absent pulmonary valve or atrioventricular septal defect, at our institution from June 2018 to April 2021. INTERVENTIONS: This review investigates the hemodynamic effects of esmolol following cardiopulmonary bypass for TOF repair. MEASUREMENTS AND MAIN RESULTS: Preoperative clinical characteristics and perioperative course were extracted from the medical record. Descriptive statistics were used. Twenty-six patients receiving perioperative esmolol after TOF repair were identified and included. Postoperative hemodynamic parameters were within a narrow range with minimal vasoactive support in most patients. Three of 26 patients experienced JET, and one of 26 of whom had a brief cardiac arrest. Median and interquartile range (IQR) for hospital and postoperative length of stay was 7 days (IQR, 6-9 d) and 6 days (IQR, 5-8 d), respectively. There were no 30-day or 1-year mortalities. CONCLUSIONS: In this infant cohort, our experience is that the routine use of postoperative esmolol is associated with good cardiac output with minimal requirement for vasoactive support in most patients. We believe optimal postoperative management of infant TOF repair requires a meticulous multidisciplinary approach, which in our experience is enhanced with routine postoperative esmolol treatment.

Acquired Sinus of Valsalva Fistula and Turner Syndrome.

A 21-year old woman with a history of Turner syndrome presented with a diastolic heart murmur, dizziness, dyspnea, and intermittent chest pain. Preoperative imaging revealed a fistula from the right sinus of Valsalva into the right atrium. Turner syndrome is associated with both aortopathy and congenital heart malformations. Acquired sinus of Valsalva fistula is a rare disorder, and this report describes its presence in association with Turner syndrome.

The intraoperative use of recombinant activated factor VII in arterial switch operations.

BACKGROUND: The rate of bleeding complications following arterial switch operation is too low to independently justify a prospective randomised study for benefit from recombinant factor VIIa. We aimed to evaluate factor VIIa in a pilot study. METHODS: We performed a retrospective cohort study of patients undergoing arterial switch operation from 2012 to 2017. Nearest-neighbour propensity score matching on age, gender, weight, and associated cardiac defects was used to match 27 controls not receiving recombinant factor VIIa to 30 patients receiving recombinant factor VIIa. Fisher's exact test was performed to compare categorical variables. Wilcoxon's rank-sum test was used to compare continuous variables between cohorts. RESULTS: Post-operative thrombotic complications were not associated with factor VIIa administration (Odds Ratio (OR) 0.28, 95% CI 0.005-3.77, p = 0.336), nor was factor VIIa administration associated with any re-explorations for bleeding. No intraoperative transfusion volumes were different between the recombinant factor VIIa cohort and controls. Post-operative prothrombin time (10.8 [10.3-12.3] versus 15.9 [15.1-17.2], p < 0.001) and international normalised ratio (0.8 [0.73-0.90] versus 1.3 [1.2-1.4], p < 0.001]) were lower in recombinant factor VIIa cohort relative to controls. CONCLUSIONS: In spite of a higher post-bypass packed red blood cell transfusion requirement, patients receiving recombinant factor VIIa had a similar incidence of bleeding post-operatively. With no difference in thrombotic complications, and with improved post-operative laboratory haemostasis, a prospective randomised study is warranted to evaluate recombinant factor VIIa.

Low antithrombin levels in neonates and infants undergoing congenital heart surgery result in more red blood cell and plasma transfusion on cardiopulmonary bypass.

BACKGROUND: Neonates have lower levels of antithrombin (AT) due to immature liver synthetic function. AT deficiency may lead to inadequate anticoagulation with heparin during cardiac surgery resulting in consumption of coagulation factors and increased blood transfusion. The goal of this study is to examine the effect of AT level on the transfusion requirements of neonates and infants undergoing open heart surgery. STUDY DESIGN AND METHODS: This is a prospective, observational study at a tertiary pediatric referral center. Neonates and infants up to 6 months of age undergoing congenital heart surgery with cardiopulmonary bypass (CPB) were enrolled. Demographic, intraoperative, transfusion, and complications data were collected. Preoperative AT level was measured after induction of anesthesia. Prior to separation from CPB, a second blood sample was drawn and AT, thrombin antithrombin complex (TAT), D-dimer, and anti-Xa levels were measured. Linear and logistic regression were performed for data analysis. RESULTS: Preoperative low AT level was significantly associated with increased transfusion of red blood cells (RBCs) and fresh frozen plasma (FFP) during CPB, but not after separation from CPB. The incidence of thrombosis and re-operation were not associated with preoperative AT levels. There was no association between TAT, D-dimer, and anti-Xa levels at the end of CPB and preoperative AT levels. CONCLUSION: Low preoperative AT level is associated with increased transfusion of RBC and FFP on CPB in neonates and infants undergoing congenital heart surgery. Low preoperative AT level did not result in coagulation activation after CPB and after surgery.

Results of a phase 1 multicentre investigation of dexmedetomidine bolus and infusion in corrective infant cardiac surgery.

BACKGROUND: Dexmedetomidine (DEX) is increasingly used intraoperatively in infants undergoing cardiac surgery. This phase 1 multicentre study sought to: (i) determine the safety of DEX for cardiac surgery with cardiopulmonary bypass; (ii) determine the pharmacokinetics (PK) of DEX; (iii) create a PK model and dosing for steady-state DEX plasma levels; and (iv) validate the PK model and dosing. METHODS: We included 122 neonates and infants (0-180 days) with D-transposition of the great arteries, ventricular septal defect, or tetralogy of Fallot. Dose escalation was used to generate NONMEM® PK modelling, and then validation was performed to achieve low (200-300 pg ml-1), medium (400-500 pg ml-1), and high (600-700 pg ml-1) DEX plasma concentrations. RESULTS: Five of 122 subjects had adverse safety outcomes (4.1%; 95% confidence interval [CI], 1.8-9.2%). Two had junctional rhythm, two had second-/third-degree atrioventricular block, and one had hypotension. Clearance (CL) immediately postoperative and CL on CPB were reduced by approximately 50% and 95%, respectively, compared with pre-CPB CL. DEX clearance after CPB was 1240 ml min-1 70 kg-1. Age at 50% maximum clearance was approximately 2 days, and that at 90% maximum clearance was 18 days. Overall, 96.1% of measured DEX concentrations fell within the 5th-95th percentile prediction intervals in the PK model validation. Dosing strategies are recommended for steady-state DEX plasma levels ranging from 200 to 1000 pg ml-1. CONCLUSIONS: When used with a careful dosing strategy, DEX results in low incidence and severity of adverse safety events in infants undergoing cardiac surgery with cardiopulmonary bypass. This validated PK model should assist clinicians in selecting appropriate dosing. The results of this phase 1 trial provide preliminary data for a phase 3 trial of DEX neuroprotection. CLINICAL TRIALS REGISTRATION: NCT01915277.

Neurologic Injury in Neonates Undergoing Cardiac Surgery.

Neurodevelopmental outcomes after neonatal congenital heart surgery are significantly influenced by brain injury detectable by MRI imaging techniques. This brain injury can occur in the prenatal and postnatal periods even before cardiac surgery. Given the significant incidence of new MRI brain injury after cardiac surgery, much work is yet to be done on strategies to detect, prevent, and treat brain injury in the neonatal period in order to optimize longer-term neurodevelopmental outcomes.

Selected 2018 Highlights in Congenital Cardiac Anesthesia.

THIS ARTICLE IS a review of the highlights of pertinent literature published during the 12 months of 2018 that is of interest to the congenital cardiac anesthesiologist. During a search of the US National Library of Medicine PubMed database, several topics that displayed significant contributions to the field in 2018 emerged. The authors of the present review consider the following topics noteworthy: the patient with high-risk congenital heart disease (CHD) presenting for noncardiac surgery, cardiopulmonary resuscitation in infants and children with CHD, dexmedetomidine use in pediatric patients, point-of-care lung ultrasound, and regional anesthesia in pediatric cardiac surgery.

Elevated arterial blood pressure after superior cavo-pulmonary anastomosis is associated with elevated pulmonary artery pressure and cerebrovascular dysautoregulation.

BACKGROUND: Elevated arterial blood pressure (ABP) is common after superior bidirectional cavopulmonary anastomosis (BCPA). The effects of elevated ABP after BCPA on cerebrovascular hemodynamics are unknown. We sought to determine the relationship between elevated ABP and cerebrovascular autoregulation after BCPA. METHODS: Prospective, observational study on infants with single-ventricle physiology after BCPA surgery. Continuous recordings of mean ABP, mean cavopulmonary artery pressure (PAP), near-infrared spectroscopy measures of cerebral oximetry (regional cerebral oxygen saturation (rSO2)), and relative cerebral blood volume index were obtained from admission to extubation. Autoregulation was measured as hemoglobin volume index (HVx). Physiologic variables, including the HVx, were tested for variance across ABP. RESULTS: Sixteen subjects were included in the study. Elevated ABP post-BCPA was associated with both, elevated PAP (P<0.0001) and positive HVx (dysautoregulation; P<0.0001). No association was observed between ABP and alterations in rSO2. Using piecewise regression, the relationship of PAP to ABP demonstrated a breakpoint at 68 mm Hg (interquartile range (IQR) 62-70 mm Hg). Curve fit of HVx as a function of ABP identified optimal ABP supporting robust autoregulation at a median ABP of 55 mm Hg (IQR 51-64 mm Hg). CONCLUSIONS: Elevated ABP post-BCPA is associated with cerebrovascular dysautoregulation, and elevated PAP. The effects, of prolonged dysautoregulation within this population, require further study.

Anesthesia for the patient with congenital heart disease presenting for noncardiac surgery.

PURPOSE OF REVIEW: To summarize recent publications emphasizing the changes in the population of patients with congenital heart disease and trends in the anesthetic and perioperative care of these patients presenting for noncardiac procedures. RECENT FINDINGS: It has been reported that children with congenital heart disease presenting for noncardiac surgery are at an increased anesthetic risk. This risk has become better defined. The patients at highest risk are infants with a functional single ventricle and patients with suprasystemic pulmonary hypertension, left ventricular outflow tract obstruction or dilated cardiomyopathy. Familiarity with the physiology and perioperative implications of the stages of single ventricle palliation is critical. The anesthetic approach, monitoring, conduct of surgery and postoperative care and outcomes are variable in this patient population. Recent literature reflects the growing number of children with ventricular assist devices and the management of these patients for noncardiac procedures. Cardiac imaging modalities provide diagnostic information, and strategies for reducing anesthetic risk for these procedures are of great interest. Pharmacologic trends and the application of technology are reviewed. SUMMARY: The identification of high-risk patients, multidisciplinary decision-making and planning and careful anesthetic management and monitoring are critical for optimizing outcomes in children with congenital heart disease presenting for noncardiac procedures.