Comparison of Bivalirudin Versus Heparin for Maintenance Systemic Anticoagulation During Adult and Pediatric Extracorporeal Membrane Oxygenation.

OBJECTIVES: To provide a comparative analysis of conventional heparin-versus bivalirudin-based systemic anticoagulation in adult and pediatric patients supported on extracorporeal membrane oxygenation. DESIGN: Retrospective chart review study of adult and pediatric patients receiving extracorporeal membrane oxygenation from January 1, 2014, to October 1, 2019. SETTING: A large, high-volume tertiary referral adult and pediatric extracorporeal membrane oxygenation center. PATIENTS: Four hundred twenty-four individuals requiring extracorporeal membrane oxygenation support and systemically anticoagulated with either unfractionated heparin (223 adult and 65 pediatric patients) or bivalirudin (110 adult and 24 pediatric patients) were included. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Digital data abstraction was used to retrospectively collect patient details. The majority of both groups were cannulated centrally (67%), and the extracorporeal membrane oxygenation type was predominantly venoarterial (84%). The adult bivalirudin group had a greater occurrence of heparin-induced thrombocytopenia (12% vs 1%; p < 0.01) and was more likely to require postcardiotomy extracorporeal membrane oxygenation (36% vs 55%; p < 0.01). There were no statistical differences between the groups in regards to age, sex, and extracorporeal membrane oxygenation initiation location. The main finding was a reduced mortality in the adult bivalirudin group (odds ratio, 0.39; p < 0.01), whereas no difference was noted in the pediatric group. A significant reduction in the composite transfusion requirement in the first 24 hours was noted in the pediatric bivaluridin group with an odds ratio of 0.28 (p = 0.02). Groups did not differ in regard to laboratories per day, anticoagulant dose adjustments, or ischemic complications. CONCLUSIONS: When compared with heparin-based systemic anticoagulation, bivalirudin demonstrated feasibility and safety as established by the absence of increases in identifiable adverse outcomes while manifesting substantial improvements in hospital mortality in adult patients. Further studies are necessary to corroborate these findings and further elucidate the role of bivalirudin during extracorporeal membrane oxygenation support.

Thrombin Generation and Antithrombin Activity in Infants Undergoing Cardiopulmonary Bypass-An Exploratory Study.

OBJECTIVES: Coagulopathic bleeding is a major complication of pediatric cardiac surgery. Investigating perioperative dynamics of thrombin generation and antithrombin (AT) activity might provide more insight into the underlying mechanisms of coagulopathy. This can help develop a targeted hemostatic approach in the future. The authors hypothesized that there is a decline in both thrombin generation and AT activity in infants undergoing cardiopulmonary bypass (CPB). DESIGN: Prospective observational study. SETTING: Single academic medical center. PARTICIPANTS: Infants <10 kg of weight undergoing cardiac surgery with CPB. INTERVENTIONS: Blood specimen collection and testing. MEASUREMENTS AND RESULTS: The authors performed assays of thrombin generation and AT activity on the samples of platelet-poor plasma of 25 infants, repeating them at 3 points: before CPB and heparinization, after separation from CPB and protamine administration, and after chest closure. The authors observed a statistically significant decline in thrombin generation shortly after separation from CPB compared with baseline. The geometric mean for lag time was prolonged (4.0 v 5.5 minutes, p = 0.013), and peak thrombin and the net amount of generated thrombin declined almost 3-fold (80.7 v 25.1 nmol, p < 0.001; 1264 v 476 nmol, p < 0.001, respectively). This was accompanied by a decline in AT activity (59.8 v 50.1, p = 0.001). After platelet and cryoprecipitate transfusion, at the case conclusion AT activity had recovered marginally (59.8 v 55.4, p = 0.042), but thrombin generation remained reduced. CONCLUSIONS: In pediatric patients <10 kg undergoing cardiac surgery with CPB, thrombin generation and AT activity decline and do not recover completely after transfusion of platelets and cryoprecipitate.

Extracorporeal membrane oxygenation, Berlin, and ventricular assist devices: a primer for the cardiologist.

PURPOSE OF REVIEW: Mechanical circulatory support (MCS) has become an indispensable tool in the management of children with impending respiratory and cardiac failure. Though extracorporeal membrane oxygenation (ECMO) was classically the only form of support available to pediatric patients, considerable advances have allowed ventricular assist devices (VADs) to become increasingly utilized in children. This review provides an update of recent advances in ECMO and VAD management in children. RECENT FINDINGS: The options for mechanical support in infants and small children with end-stage heart failure are limited. As such, the greatest advances in the past decade have come in the successful adoption of the Berlin Heart EXCOR device, with a marked improvement in survival to transplant over ECMO. Further advances have been made in the use of adult VADs in children. For instance, the HeartWare HVAD has been utilized in children as young as 3 years of age, despite being designed for use in adult patients. SUMMARY: The availability of mechanical support options for children remains limited to ECMO and a small number of VADs. While outcomes of VAD support in pediatric patients have been promising, further study in smaller and more complex pediatric patients is necessary.

National In-Hospital Outcomes of Mechanical Mitral Valve Replacement in the Pediatric Population.

Background: National data about the outcomes of children undergoing mechanical mitral valve replacement (m-MVR) are scarce. Methods: A retrospective review of hospitalizations from the Kids' Inpatient Database was performed for patients ≤18 years of age in the United States. A total of 500 patients underwent m-MVR in 2009, 2012, 2016, and 2019. Patients with single ventricle physiology were excluded (n = 13). These patients were categorized into three groups according to age: neonates (<1 month, n = 20), infants (1-12 months, n = 76 patients), and children (1-18 years, n = 404). Outcomes were compared between the three groups. Results: The proportion of m-MVR involving children undergoing MV procedures (repair and replacement) has increased from 17.3% in 2009 to 30.8% in 2019 (Ptrend < .01). History of cardiac surgery was present in 256 patients (51.2%). Concomitant procedures were performed in 119 patients (23.8%). Intra- or postoperative extracorporeal membrane oxygenation was required in 19 patients (3.8%). The overall in-hospital mortality was 4.8% and was significantly higher in neonates and infants compared with older children (10% vs 11.8% vs 3.2%, P = .003). The length of hospital stay was longer in the neonatal group (median, 57 days, interquartile range, [24.8-90] vs 29.5 days [15.5-61] vs 10 days [7-18], P < .01). Nonhome discharges were more common in neonates and infants (40% vs 36.8% vs 13.1%, P < .01). Conclusion: Mechanical mitral valve replacement is increasingly performed over time with acceptable in-hospital morbidity and mortality, especially in older children and adolescents. Neonates and infants are associated with worse hospital survival, prolonged hospitalization, and significant rates of nonhome discharges.

A multicenter outcomes analysis of children with severe viral respiratory infection due to human metapneumovirus.

OBJECTIVE: To investigate the impact of human metapneumovirus on morbidity and mortality outcomes in children with severe viral respiratory infection. DESIGN: Retrospective cohort study. SETTING: ICU, either PICU or cardiac ICU, at three urban academic tertiary care children's hospitals. PATIENTS: All patients admitted to an ICU with laboratory-confirmed human metapneumovirus infection between January 2010 and June 2011. INTERVENTIONS: We captured demographic and clinical data and analyzed associated morbidity and mortality outcomes. MEASUREMENTS AND MAIN RESULTS: There were 111 patients with laboratory-confirmed human metapneumovirus admitted to an ICU at one of the three participating institutions during the period of study. The median hospital length of stay was 7 days (interquartile range 4-18 days) and median ICU length of stay was 4 days (interquartile range 1-10 days). Ten patients (9%) did not survive to discharge. Predisposing factors associated with increased mortality included female gender (p = 0.002), presence of a chronic medical condition (p = 0.04), and hospital acquisition of human metapneumovirus infection (p = 0.006). Adjusting for female gender, chronic medical conditions, hospital acquisition of infection and severity of illness score, logistic regression analysis demonstrated that female gender, hospital acquisition of infection, and chronic medical conditions each independently increased the odds of mortality (odds ratios 14.8, 10.7, and 12.7, respectively). CONCLUSIONS: Analysis of our results suggests that there is substantial morbidity and mortality associated with severe viral respiratory infection due to human metapneumovirus in children. Female gender, hospital acquisition of human metapneumovirus infection, and presence of chronic medical conditions each independently increases mortality. The burden of illness from human metapneumovirus on the ICU in terms of resource utilization may be considerable.

Adults With Tetralogy of Fallot: Early Postoperative Outcomes and Risk Factors for Complications.

OBJECTIVE: To report the early postoperative outcomes in adults with tetralogy of Fallot (TOF) undergoing cardiac surgery and to identify patient factors associated with complications. PATIENTS AND METHODS: We performed a single-institution retrospective review of adults with TOF who underwent cardiac surgery from January 8, 2008, through June 21, 2018. Patients' characteristics, preoperative imaging, surgical interventions, outcomes, and complications were analyzed. RESULTS: There were 219 adults with TOF (mean age, 40 years; range, 18-83 years; 88 [40%] female) in the study. Surgical interventions included repair or replacement of the pulmonary valve (n=199 [91%]), tricuspid valve (n=70 [32%]), mitral valve (n=13 [5.9%]), and aortic valve (n=8 [3.7%]). Three patients (1.4%) underwent first-time TOF repair. The 30-day mortality rate was 1.4% (n=3). Early postoperative complications occurred in 66 (30%) and included arrhythmias requiring treatment, dialysis requirement, liver dysfunction, respiratory failure, infection, reoperation, cardiac arrest, mechanical circulatory support, and death. Multivariate analysis found older age at current surgery (odds ratio [OR], 1.04 per year; 95% CI, 1.01 to 1.06; P<.001), longer cardiopulmonary bypass time (OR, 1.01 per minute; 95% CI, 1.01 to 1.02; P<.001), right ventricular systolic dysfunction (OR, 1.31; 95%, CI 1.02 to 1.69; P=.03), diabetes mellitus (OR, 3.50; 95% CI, 1.20 to 10.2; P=.02), and history of initial palliative surgery (OR, 1.99; 95% CI, 1.01 to 3.91; P=.05) as independent predictors of complications. CONCLUSION: Surgical interventions for adult patients with TOF can be performed with low early morbidity and mortality. Clinical characteristics and preoperative testing parameters can predict risk for complications in the postoperative period.

Improvement in Oxygenation Utilizing Transpulmonary Pressure Monitoring for Optimal Positive End-Expiratory Pressure in Pediatric Acute Respiratory Distress Syndrome: A Case Report.

In severe pediatric acute respiratory distress syndrome, data are lacking on methods to measure and set optimal positive end-expiratory pressure. We present a 2-year-old girl with Trisomy 21 who developed severe pediatric acute respiratory distress syndrome and refractory hypoxemia from human metapneumovirus pneumonia. Esophageal manometry was utilized to measure transpulmonary pressure, and positive end-expiratory pressure was increased to 19 cm H2O, resulting in rapid improvement in oxygenation. Hemodynamics remained adequate without intervention. The patient improved and survived without sequelae. Our case suggests that transpulmonary pressure monitoring should be studied as an adjunct to improve outcomes in pediatric acute respiratory distress syndrome.

Vasopressor magnitude predicts poor outcome in adults with congenital heart disease after cardiac surgery.

BACKGROUND: High levels of vasoactive inotrope support (VIS) after congenital heart surgery are predictive of morbidity in pediatric patients. We sought to discern if this relationship applies to adults with congenital heart disease (ACHD). METHODS: We retrospectively studied adult patients (≥18 years old) admitted to the intensive care unit after cardiac surgery for congenital heart disease from 2002 to 2013 at Mayo Clinic. Vasoactive medication dose values within 96 hours of admission were examined to determine the relationship between VIS score and poor outcome of early mortality, early morbidity, or complication related morbidity. RESULTS: Overall, 1040 ACHD patients had cardiac surgery during the study time frame; 243 (23.4%) met study inclusion criteria. Sixty-two patients (25%), experienced composite poor outcome [including eight deaths within 90 days of hospital discharge (3%)]. Thirty-eight patients (15%) endured complication related early morbidity. The maximum VIS (maxVIS) score area under the curve was 0.92 (95% CI: 0.86-0.98) for in-hospital mortality; and 0.82 (95% CI: 0.76-0.89) for combined poor clinical outcome. On univariate analysis, maxVIS score ≥3 was predictive of composite adverse outcome (OR: 14.2, 95% CI: 7.2-28.2; P < 0.001), prolonged ICU LOS ICU LOS (OR: 19.2; 95% CI: 8.7-42.1; P < 0.0001), prolonged mechanical ventilation (OR: 13.6; 95% CI: 4.4-41.8; P < 0.0001) and complication related morbidity (OR: 7.3; 95% CI: 3.4-15.5; P < 0.0001). CONCLUSIONS: MaxVIS score strongly predicted adverse outcomes and can be used as a risk prediction tool to facilitate early intervention that may improve outcome and assist with clinical decision making for ACHD patients after cardiac surgery.