Comparison of Time Within Therapeutic Range Using Anti-Factor Xa Versus Activated Partial Thromboplastin Time Monitoring of Unfractionated Heparin in Children.

OBJECTIVE: To compare unfractionated heparin (UFH) monitoring using time in therapeutic range of activated partial thromboplastin time (aPTT) versus anti-factor Xa activity (anti-Xa) in children. METHODS: This retrospective chart review, with data between October 2015 and October 2019, included pediatric patients younger than 18 years on therapeutic UFH infusion with aPTT or anti-Xa monitoring. Patients receiving extracorporeal membrane oxygenation, dialysis, concomitant anticoagulants, prophylactic UFH, no stated goal, and UFH administered for less than 12 hours were excluded. The primary outcome compared the percentage of time in therapeutic range between aPTT and anti-Xa. Secondary outcomes included time to first therapeutic value, UFH infusion rates, mean rate adjustments, and adverse events. RESULTS: A total of 65 patients were included, with 33 aPTT patients and 32 anti-Xa patients, representing 39 UFH orders in each group. Baseline characteristics were similar between groups, with an overall mean age of 1.4 years and mean weight of 6.7 kg. The anti-Xa cohort demonstrated a statistically significantly higher percentage of time in therapeutic range compared with the aPTT group (50.3% vs 26.9%, p = 0.002). The anti-Xa group also demonstrated a trend toward decreased time to first therapeutic value compared with aPTT (14 vs 23.2 hours, p = 0.12). Two patients in each group experienced new or worsening thrombosis. Six patients in the aPTT cohort experienced bleeding. CONCLUSIONS: This study demonstrated greater time was spent within therapeutic range for children receiving UFH monitored with anti-Xa compared with aPTT. Future studies should assess clinical outcomes in a larger population.

Utility of Routine Head Ultrasounds in Infants on Extracorporeal Life Support: When is it Safe to Stop Scanning?

Intracranial hemorrhage (ICH) can be a devastating complication of extracorporeal life support (ECLS); however, studies on the timing of ICH detection by head ultrasound (HUS) are from 2 decades ago, suggesting ICH is diagnosed by day 5 of ECLS. Given advancements in imaging and critical care, our aim was to evaluate if the timing of ICH diagnosis in infants on ECLS support has changed. Patients <6 months old undergoing ECLS 2011-2020 at a tertiary care children's hospital were included. Primary outcome was timing of ICH diagnosis on HUS. Seventy-four infants underwent ECLS for cardiac (54%) or pulmonary (46%) indications. Venoarterial ECLS was most common (88%). Median ECLS duration was 6 days (range 1-26). Sixteen patients were diagnosed with ICH (21.6%), at a median of 2 days postcannulation (range 1-4). Nearly all were <4 weeks old at cannulation (93.8%). In conclusion, one-fifth of infants developed ICH diagnosed by HUS while on ECLS, all within the first 4 days of ECLS, consistent with previous literature. Despite advances in critical care and imaging technology, the temporality of ICH diagnosis in infants on ECLS is unchanged.

Successful extracorporeal life support in a pediatric trauma patient following angioembolization of pelvic hemorrhage.

Extracorporeal Life Support (ECLS) is rarely used in pediatric trauma patients due to bleeding risk, and the use of ECLS following angioembolization of traumatic hemorrhage has never been reported in a child. We report a case of a 10-year-old boy run over by a parade float resulting in severe thoracic, abdominal, and pelvic trauma, with hemorrhage from pelvic fractures requiring massive transfusion. Due to ongoing blood product requirements and contrast extravasation near the symphysis pubis, angioembolization of the internal iliac arteries was performed. Extreme hypoxemia persisted despite maximal ventilator support due to pulmonary contusions and aspiration pneumonitis. Six hours after angioembolization, venovenous ECLS was initiated. Following an initial heparin bolus, ECLS was run without anticoagulation for 12 h, but development of circuit clot required resumption of low-dose heparin. After four days, his respiratory status improved substantially and ECLS was discontinued. There were no hemorrhagic complications. The patient was discharged home in good health following inpatient rehabilitation. In this case, ECLS was successfully used in the treatment of post-traumatic respiratory failure 6 h following angioembolization of pelvic hemorrhage in a pediatric trauma patient. Further research is needed to determine the safest interval between hemorrhage control and ECLS in severely injured children.

Interprofessional/interdisciplinary teamwork during the early COVID-19 pandemic: experience from a children's hospital within an academic health center.

The COVID-19 pandemic has created multiple, complex and intense demands on hospitals, including the need for surge planning in the many locations outside epicenters such as northern Italy or New York City. We here describe such surge planning in an Academic Health Center that encompasses a children's hospital. Interprofessional teams from every aspect of inpatient care and hospital operations worked to prepare for a COVID-19 surge. In so doing, they successfully innovated ways to integrate pediatric and adult care and maximize bed capacity. The success of this intense collaborative effort offers an opportunity for ongoing teamwork to enhance efficient, effective, and high-quality patient care.

Chronic hypoxia augments uterine artery distensibility and alters the circumferential wall stress-strain relationship during pregnancy.

Pregnancy-associated increases in uterine artery (UA) blood flow are due, in part, to vasoactive and growth-related changes that enlarge UA diameter. Although active and passive mechanical factors can contribute to this enlargement, their role is less well understood. We hypothesized that pregnancy increased UA distensibility and/or decreased myogenic tone. Given the fetal growth restriction and lower UA flow seen under chronic hypoxia, we further hypothesized that chronic hypoxia opposed these normal active and passive mechanical changes. UA were isolated from 12 nonpregnant and 12 pregnant (0.7 gestation) guinea pigs housed under normoxia or chronic hypoxia (3,960 m) and studied by pressure myography. Pregnancy increased UA diameter similarly under normoxia and hypoxia. Although chronic hypoxia raised resting tone in UA from nonpregnant guinea pigs to approximately 20% and tone was greater in preconstricted pregnant chronically hypoxic vs. normoxic UA (both P<0.01), there was an absence of myogenic response (i.e., an increase in tone with rising pressure) in all groups. Pregnancy increased UA distensibility 1.5-fold but did not change stiffness or the stress-strain relationship. Compared with vessels from normoxic pregnant animals, hypoxic pregnancy raised UA distensibility fourfold, decreased stiffness (rate constant b=3.80+/-1.06 vs. 8.92+/-1.25, respectively, P<0.01), lowered elastin by 50%, and shifted the stress-strain relationship upward such that four times as much strain was present at a given stress. We concluded that increased distensibility and low myogenic tone contribute to enlarging UA diameter and raising UA blood flow during pregnancy. Chronic hypoxia exaggerates the rise in distensibility and alters the stress-strain relationship in ways that may provoke vascular injury.