Clinical outcomes in critically ill children on extracorporeal membrane oxygenation with severe thrombocytopenia.

INTRODUCTION: As international guidelines suggest keeping the platelet count between 50 and 100 × 109 cells/L in children on extracorporeal membrane oxygenation (ECMO), platelet transfusions are administered to two-thirds of ECMO days, and up to 70% of these patients still bleed. We aim to describe outcomes in critically ill children who develop severe thrombocytopenia on ECMO. METHODS: Single-center retrospective study, enrolling critically ill children on ECMO admitted at Children's Memorial Hermann, TX, between 1/2018 and 12/2022, with at least one platelet count below 50 × 109 cells/L (severe thrombocytopenia). Platelet counts were measured four times a day. We report platelet transfusion, bleeding, hemolysis, and clotting events within 6 h after transfusion, as well as ECMO duration and mortality. RESULTS: We enrolled 54 patients representing 337 ECMO days and 1190 platelet counts. Median weight was 3.7 kg and 54% were male. Severe thrombocytopenia was observed in 56% of platelet counts. Severe thrombocytopenia was not associated with bleeding in the subsequent 6 h (18% vs 20%, p = .95), but was associated with more frequent platelet transfusions (18% vs 11%, p = .001). There was no correlation between time spent with severe thrombocytopenia and the duration of ECMO (R2 = 0.03). While the time spent with severe thrombocytopenia was not associated with on-ECMO mortality rate (p = .36), there was an association with in-hospital mortality rate (p = .003). CONCLUSIONS: Our results indicate a restrictive platelet transfusion strategy is not associated with higher proportions of subsequent bleeding, duration of ECMO, or on-ECMO mortality rate. Multicenter studies are needed to evaluate further the appropriateness of this strategy.

Pulmonary Edema and Hypoxic Respiratory Failure.

OBJECTIVES: The purpose of this chapter is to outline the causes, physiology, pathophysiology, and management strategies for hydrostatic and permeability pulmonary edema and hypoxic respiratory failure. DATA SOURCE: MEDLINE and PubMed. CONCLUSION: The pulmonary parenchyma and vasculature are at high risk in conditions where injury occurs to the lung and or heart. A targeted approach that uses strategies that optimize the particular pathophysiology of the parenchyma and vasculature is required.

Targeted interventions improve shared agreement of daily goals in the pediatric intensive care unit.

OBJECTIVE: To improve communication during daily rounds using sequential interventions. DESIGN: Prospective cohort study. SETTING: Multidisciplinary pediatric intensive care unit in a university hospital. SUBJECTS: The multidisciplinary rounding team in the pediatric intensive care unit, including attending physicians, physician trainees, and nurses. INTERVENTIONS: Daily rounds on 736 patients were observed over a 9-month period. Sequential interventions were timed 8-12 wks apart: 1) implementing a new resident daily progress note format; 2) creating a performance improvement "dashboard"; and 3) documenting patients' daily goals on bedside whiteboards. MEASUREMENTS AND MAIN RESULTS: After all interventions, team agreement with the attending physician's stated daily goals increased from 56.9% to 82.7% (p < .0001). Mean agreement increased for each provider category: 65.2% to 88.8% for fellows (p < .0001), 55.0% to 83.8% for residents (p < .0001), and 54.1% to 77.4% for nurses (p < .0001). In addition, significant improvements were noted in provider behaviors after interventions. Barriers to communication (bedside nurse multitasking during rounds, interruptions during patient presentations, and group disassociation) were reduced, and the use of communication facilitators (review of the prior day's goals, inclusion of bedside nurse input, and order read-back) increased. The percentage of providers reporting being "very satisfied" or "satisfied" with rounds increased from 42.6% to 78.3% (p < .0001). CONCLUSIONS: Shared agreement of patients' daily goals among key healthcare providers can be increased through process-oriented interventions. Improved agreement will potentially lead to improved quality of patient care and reduced medical errors.

Mechanical ventilation in the pediatric cardiac intensive care unit: the essentials.

Ventilating a child or newborn in the postoperative course after repair of congenital heart disease requires a solid basic understanding of respiratory system mechanics (pressure-volume relationship of the respiratory system and the concept of its time constants) and cardiopulmonary physiology. Furthermore, careful attention has to be paid to avoid damaging the lungs by potentially injurious mechanical ventilation. Optimizing ventilator settings during controlled and assisted ventilation, allowing as early as possible for spontaneous ventilation by still assisting mechanically the patient's respiratory efforts are important features for lung protection, for minimizing potential hemodynamic side effects of positive pressure ventilation, and for early weaning from mechanical ventilation. In the search for being less invasive, the use of noninvasive ventilation in the cardiac intensive care setting is rapidly increasing despite still lacking evidence of its theoretical superiority and requires good knowledge of specific techniques and equipment available for this approach in this setting. This review will address many of these aspects and highlight the essentials to be known when ventilating a child in the Cardiac Intensive Care Unit (CICU).

End-tidal and arterial carbon dioxide measurements correlate across all levels of physiologic dead space.

BACKGROUND: End-tidal carbon dioxide (P(ETCO(2))) is a surrogate, noninvasive measurement of arterial carbon dioxide (P(aCO(2))), but the clinical applicability of P(ETCO(2)) in the intensive care unit remains unclear. Available research on the relationship between P(ETCO(2)) and P(aCO(2)) has not taken a detailed assessment of physiologic dead space into consideration. We hypothesized that P(ETCO(2)) would reliably predict P(aCO(2)) across all levels of physiologic dead space, provided that the expected P(ETCO(2))-P(aCO(2)) difference is considered. METHODS: Fifty-six mechanically ventilated pediatric patients (0-17 y old, mean weight 19.5 +/- 24.5 kg) were monitored with volumetric capnography. For every arterial blood gas measurement during routine care, we measured P(ETCO(2)) and calculated the ratio of dead space to tidal volume (V(D)/V(T)). We assessed the P(ETCO(2))-P(aCO(2)) relationship with Pearson's correlation coefficient, in 4 V(D)/V(T) ranges. RESULTS: V(D)/V(T) was 0.7 for 54 measurements (11%). The correlation coefficients between P(ETCO(2)) and P(aCO(2)) were 0.95 (mean difference 0.3 +/- 2.1 mm Hg) for V(D)/V(T) 0.7. CONCLUSIONS: There were strong correlations between P(ETCO(2)) and P(aCO(2)) in all the V(D)/V(T) ranges. The P(ETCO(2))-P(aCO(2)) difference increased predictably with increasing V(D)/V(T).

Probiotic administration and the incidence of nosocomial infection in pediatric intensive care: a randomized placebo-controlled trial.

OBJECTIVE: To evaluate the efficacy of probiotics in reducing the rates of nosocomial infection in pediatric intensive care. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: A 16-bed pediatric intensive care unit in a university-affiliated children's hospital. PATIENTS: Sixty-one pediatric patients were enrolled from April 2004 until December 2004. Screening of all patients admitted occurred on a daily basis. Patients were excluded if they had the following: evidence/suspicion of intestinal perforation, evidence/suspicion of mechanical gastrointestinal obstruction, absolute neutrophil count

Inhaled nitric oxide results in deteriorating hemodynamics when administered during cardiopulmonary bypass in neonatal swine.

OBJECTIVE: To evaluate if inhaled nitric oxide (iNO) has a lung-protective effect when it is delivered during the ischemic phase of neonatal cardiopulmonary bypass (CPB). DESIGN: Prospective, randomized, controlled study. SETTING: Surgical research laboratory in a university hospital. SUBJECTS: Thirty-five neonatal swine. INTERVENTIONS: One-week-old swine (2.1-3.4 kg) were exposed to cool, low-flow CPB bypass designed to mimic the bypass used during neonatal congenital heart repair. Animals were randomized to four groups: a) CPB without exposure to iNO (n = 9); b) iNO delivery only during CPB with discontinuation of iNO at the start of reperfusion (n = 7); c) iNO delivery both during CPB and during the 90-min post-CPB observation period (n = 7); and d) iNO delivery only after separation from CPB (n = 7). Each animal was placed on nonpulsatile CPB and cooled to a nasopharyngeal temperature of 18 degrees C (64 degrees F). Low-flow CPB (35 mL.kg(-1).min(-1)) was instituted for 90 mins. The blood flow then was returned to 100 mL.kg(-1).min(-1), and the animals were warmed to 36 degrees C (96.8 degrees F) before separation from CPB. Animals were followed 90 mins post-CPB. Lung tissue was harvested and evaluated for myeloperoxidase activity, wet/dry weight, and lung pathology. Five animals underwent sham protocol, receiving instrumentation but not exposure to CPB or iNO. MEASUREMENTS AND MAIN RESULTS: We measured pulmonary vascular resistance, right ventricular output, and pulmonary artery pressure in all animals at 30, 60, and 90 mins following separation from CPB. Study animals that received iNO during the ischemic period of CPB were not protected against CPB-induced lung injury. Those animals treated with iNO both during and after CPB trended worse than those receiving iNO only after CPB. Inhaled nitric oxide delivered only after separation from CPB improved the hemodynamic variables compared with all other groups. Differences in lung wet/dry weight, myeloperoxidase, and pathology were not significantly different among groups. CONCLUSIONS: The delivery of iNO during the ischemic period of CPB does not protect against CPB-induced lung injury in a neonatal piglet CPB model. Delivery of iNO during this phase of CPB may, in fact, worsen the post-CPB hemodynamic condition. Inhaled nitric oxide should be used with caution during periods of low pulmonary blood flow CPB. Inhaled nitric oxide remains effective for reducing pulmonary vascular resistance after CPB.

Effects of maternal nicotine exposure on branching morphogenesis of mouse fetal lung: in vivo and in vitro studies.

Epidemiological evidence suggests that premature infants born to mothers who smoke have a lower incidence of neonatal respiratory distress syndrome. The mechanism has been proposed to be due to increased lung maturity. This in vivo study investigated the effect of maternal nicotine on lung development by evaluating the airway branching morphogenesis (ABM) in mice fetuses. Nicotine (0, 2 and 3 mg/kg/day) was administered intraperitoneally to pregnant mice from gestation day 9 to day 12 (4 days). ABM was determined on day 13 by photomicrographic analysis. The results revealed a significant reduction in ABM in the higher dose nicotine group. The mean number of airway branches was 3.7 +/- 0.1/lobe for the 3 mg/kg/day group, which was smaller than 4.6 +/- 0.2/lobe for the 2 mg/kg/day nicotine group, and 4.4 +/- 0.1/lobe for the control group (F = 9.4, p < 0.001). The mean number of buds was significantly smaller in both the 2 mg/kg/day group and the 3 mg/kg/day group (8.7 +/- 0.5/lobe, 9.0 +/- 0.4/lobe vs. 12.3 +/- 0.4/lobe in the control group, F = 20.3, p < 0.001). For the in vitro study, fetal lung lobes were isolated at the 12th gestation day. The lung explants were cultured in nicotine (0, 30, 60 ng/ml) for 48 hours; there were no differences in all the groups. The results do not support the hypothesis that nicotine stimulates fetal lung ABM either in vivo or in vitro.