Vitamin K and ECMO for neonatal hypoxic respiratory failure.

INTRODUCTION: The objectives of this retrospective cohort study were to examine the effect of vitamin K administration on hemorrhagic and thrombotic complications, blood product utilization, and outcomes in neonatal extracorporeal membrane oxygenation (ECMO). METHODS: In the pilot study, complications, blood product use, and outcome data for neonates who received (n = 21) or did not receive (n = 18) a single dose of vitamin K (5 mg) immediately after initiation of ECMO for respiratory failure between 2006 and 2010 were compared. In the validation cohort, complications and outcomes were compared for 74 consecutive neonates supported with ECMO for respiratory failure who received (n = 45) or did not receive (n = 29) additional vitamin K once daily for prothrombin time (PT) ⩾14 seconds during ECMO from 2014 to 2019. RESULTS: In the pilot study, vitamin K at ECMO initiation was associated with fewer thrombotic complications and similar hemorrhagic complications. The volume of fresh frozen plasma was higher in neonates who received vitamin K, but total blood product and other component volume did not differ between groups. ECMO run time, survival off ECMO, survival to discharge, and length of stay did not differ between cohorts. In the validation cohort, neonates who received additional vitamin K during ECMO had longer ECMO run time and length of stay, but no difference in mortality was observed. Further, thrombotic and hemorrhagic complications as well as blood product exposure were similar between cohorts. CONCLUSIONS: These data suggest that routine vitamin K administration may have limited or no benefit during neonatal ECMO.

The lifelong impact of fetal growth restriction on cardiac development.

BACKGROUND: Maternal nutrient restriction (MNR) is a widespread cause of fetal growth restriction (FGR), an independent predictor of heart disease and cardiovascular mortality. Our objective was to examine the developmental and long-term impact of MNR-induced FGR on cardiac structure in a model that closely mimics human development. METHODS: A reduction in total caloric intake spanning pregestation through to lactation in guinea pig sows was used to induce FGR. Proliferation, differentiation, and apoptosis of cardiomyocytes were assessed in late-gestation fetal, neonatal, and adult guinea pig hearts. Proteomic analysis and pathway enrichment were performed on fetal hearts. RESULTS: Cardiomyocyte proliferation and the number of mononucleated cells were enhanced in the MNR-FGR fetal and neonatal heart, suggesting a delay in cardiomyocyte differentiation. In fetal hearts of MNR-FGR animals, apoptosis was markedly elevated and the total number of cardiomyocytes reduced, the latter remaining so throughout neonatal and into adult life. A reduction in total cardiomyocyte number in adult MNR-FGR hearts was accompanied by exaggerated hypertrophy and a disorganized architecture. Pathway analysis identified genes related to cell proliferation, differentiation, and survival. CONCLUSIONS: FGR influences cardiomyocyte development during critical windows of development, leading to a permanent deficiency in cardiomyocyte number and compensatory hypertrophy in a rodent model that recapitulates human development.

Comparison of transfusion thresholds during neonatal extracorporeal membrane oxygenation.

BACKGROUND: The objective of this study was to assess complications and patient outcomes associated with a lower reflexive red blood cell (RBC) transfusion threshold for neonates undergoing extracorporeal membrane oxygenation (ECMO) for hypoxic respiratory failure. STUDY DESIGN AND METHODS: A retrospective cohort study was conducted at a single tertiary neonatal intensive care unit of neonates undergoing ECMO support for refractory hypoxic respiratory failure for more than 24 hours between December 2009 and December 2014. Seventy-two neonates received ECMO support for hypoxic respiratory failure for longer than 24 hours during the study period. Patient cohorts were determined based on transfusion threshold of hematocrit (Hct) level of less than 40% (December 2009-October 2012) and Hct level of less than 35% (November 2012-December 2014). RESULTS: Patients who had a lower threshold for transfusion (Hct < 35) had a lower mean Hct (38.3% vs. 41.4%, p < 0.0001) and received less total RBC transfusion volume (10.4 mL/kg/day vs. 13.3 mL/kg/day, p = 0.002) while undergoing ECMO support. Survival off ECMO, survival to discharge, and complication rates were similar between the cohorts. CONCLUSIONS: A lower Hct threshold of 35% is associated with a reduction in RBC transfusion volume and does not appear to alter complication rates or patient outcomes for neonates receiving ECMO support for respiratory failure.

Proportionality at birth and left ventricular hypertrophy in healthy adolescents.

BACKGROUND: Perinatal growth has important implications for cardiac development. Low birth weight is associated with cardiovascular (CV) events and mortality, and animal studies have shown that fetal growth restriction is associated with cardiac remodeling in the perinatal period leading to a permanent loss of cardiomyocyte endowment and compensatory hypertrophy. AIMS: To determine associations of birthweight (BW) and multiple proportionality indexes (body mass index (BMI); weight/length2 and Ponderal index (PI); weight/length3) at birth on one hand, with left ventricular (LV) structure and function during adolescence. SUBJECTS: 379 healthy adolescents aged 14-18 years in Augusta, Georgia. OUTCOME MEASURES: LV structure and function parameters, including intraventricular septal thickness in diastole (IVSd), LV internal dimension in diastole (LVIDd), LV internal diameter in systole (LVIDs), LV posterior wall thickness in diastole (LVPWd), relative wall thickness (RWT), midwall fractional shortening (MFS), and ejection fraction, were assessed by echocardiography. RESULTS: When associations of birthweight, birth BMI, and birth PI with LV structure and function parameters were separately evaluated with linear regression adjusting for age, sex, race, Tanner stage, socioeconomic status, and physical activity, significant positive associations of BW with LVIDd (P = 0.004), birth BMI with LV mass index (P = 0.01), and birth PI with IVSd (P = 0.02), LVPWd (P = 0.03), and LV mass index (P = 0.002) were identified. When LV structure and function parameters were compared across PI tertiles, a significant U-shaped trend for LV mass index (Pquadratic = 0.04) was identified. CONCLUSIONS: Our adolescent data suggest that proportionality at birth may identify associations between perinatal growth and cardiac remodeling independent of birthweight alone.