High-Frequency Percussive Ventilation in Viral Bronchiolitis.

BACKGROUND: High-frequency percussive ventilation (HFPV) is an alternative mode of mechanical ventilation that has been shown to improve gas exchange in subjects with severe respiratory failure. We hypothesized that HFPV use would improve ventilation and oxygenation in intubated children with acute bronchiolitis. METHODS: In this single-center prospective cohort study we included mechanically ventilated children in the pediatric ICU with bronchiolitis 1-24 months old who were transitioned to HFPV from conventional invasive mechanical ventilation from November 2018-April 2020. Patients with congenital heart disease, on extracorporeal membrane oxygenation (ECMO), and with HFPV duration < 12 h were excluded. Subject gas exchange metrics and ventilator parameters were compared before and after HFPV initiation. RESULTS: Forty-one of 192 (21%) patients intubated with bronchiolitis underwent HFPV, and 35 met inclusion criteria. Median age of cohort was 4 months, and 60% were previously healthy. All subjects with available oxygenation saturation index (OSI) measurements pre-HFPV met pediatric ARDS criteria (31/35, 89%). Mean CO2 decreased from 65.4 in the 24 h pre-HFPV to 51 (P < .001) in the 24 h post initiation. SpO2 /FIO2 was significantly improved at 24 h post-HFPV (153.3 to 209.7, P = .001), whereas the decrease in mean OSI at 24 h did not meet statistical significance (11.9 to 10.2, P = .15). The mean peak inspiratory pressure (PIP) decreased post-HFPV from 29.7 to 25.0 at 24 h (P < .001). No subjects developed an air leak or hemodynamic instability secondary to HFPV. Two subjects required ECMO, and of these, one subject died. CONCLUSIONS: HFPV was associated with significant improvement in ventilation and decreased exposure to high PIPs for mechanically ventilated children with bronchiolitis in our cohort and had a potential association with improved oxygenation. Our study shows that HFPV may be an effective alternative mode of ventilation in patients with bronchiolitis who have poor gas exchange on conventional invasive mechanical ventilation.

l-Citrulline treatment alters the structure of the pulmonary circulation in hypoxic newborn pigs.

BACKGROUND: Dysregulated nitric oxide (NO) signaling contributes to chronic hypoxia (CH)-induced pulmonary hypertension (PH). NO signaling is improved and pulmonary vascular resistance (PVR) is reduced in CH piglets treated with the l-arginine-NO precursor, l-citrulline. We hypothesized that l-citrulline might cause structural changes in the pulmonary circulation that would contribute to the reduction in PVR and that the l-citrulline-induced structural changes would be accompanied by alterations in vascular endothelial growth factor (VEGF) signaling. METHODS: We evaluated small pulmonary arterial (PA) wall thickness, lung capillary density, and protein abundances of VEGF, VEGFR2, and phospho (p)-VEGFR2 in PA and peripheral lung samples of piglets raised in the lab in CH (10%-12% O2 ) from the day of life (DOL) 2 until DOL 11 to 12 or raised in room air (normoxia) by the vendor and studied on arrival to the lab on DOL 11 to 12. Some CH piglets were treated with oral l-citrulline (1-1.5 g/kg/d) starting on the third day of hypoxia. RESULTS: PA wall thickness was 32% less and lung capillary formation was nearly doubled in l-citrulline treated than untreated CH piglets. Both of these l-citrulline-induced structural changes in the pulmonary circulation were accompanied by altered amounts of VEGF protein but not by altered amounts of either VEGFR2 or p-VEGFR2 proteins. CONCLUSIONS: Alterations in the structure of the pulmonary circulation in CH piglets by l-citrulline are unlikely to be mediated by overall VEGF signaling. Nonetheless, l-citrulline- induced structural changes should reduce PVR and thereby contribute to the amelioration of CH-induced PH.

The impact of age on mortality in patients in extremis undergoing urgent intervention.

Trauma patients admitted without vital signs have little hope of survival even with extreme interventions. We performed this study to determine the effect of age on survival in patients in extremis undergoing urgent thoracotomy. The National Trauma Database was searched for patients presenting without a systolic blood pressure (0), a Glasgow Coma Scale score less than 8, and underwent an urgent thoracotomy. Mortality was determined for pediatric (younger than 16 years) and older patients (older than 60 years) and compared. Of 708 patients, 32 (4.5%) were pediatric and 57 (8.1%) were elderly. Pediatric mortality was 93.8 per cent (30) versus 95.6 per cent (646) for patients older than 16 years (P = 0.981). Mortality in the older patients was 94.7 per cent (54) versus 95.5 per cent (622) in patients younger than 60 years (P = 0.778). Race and blunt injury were independently associated with death. However, neither pediatric (P = 0.418) nor older status (P = 0.184) was predictive. Age does not significantly impact mortality in patients in extremis who undergo urgent thoracotomy. Age should not be a contributing factor in determining who should undergo more extreme maneuvers if they present as a reasonable candidate using other criteria.

Liver herniation in gastroschisis: incidence and prognosis.

PURPOSE: Liver herniation is a rare occurrence in gastroschisis. We sought to determine the incidence and prognosis of liver herniation in patients with gastroschisis. METHODS: From December 1995 to March 2010, 117 patients with gastroschisis received care by our division. Operative reports were reviewed to identify patients with liver herniation. Logistic regression was used to determine the impact of liver herniation on survival, taking into account gestational age and birth weight. RESULTS: The incidence of liver herniation was 6%. Survival rates were 43% with liver herniation and 97% without liver herniation. Liver herniation was associated with a significantly higher rate of mortality, taking into account estimated gestational age and birth weight (P < .001). Patients who had liver herniation documented by prenatal ultrasound had significant liver herniation at birth and died postnatally. Patients with liver herniation who died required large silos and were noted to have comorbidities including lower birth weight, pulmonary hypoplasia, and sepsis. Biologic patches were necessary for closure in patients with greater extent of liver herniation. CONCLUSIONS: Liver herniation was found in 6% of patients with gastroschisis and was associated with a high rate of mortality. Liver herniation appears to be a risk factor for poor outcome in gastroschisis. Documentation of liver herniation may be helpful in prenatal consultation for gastroschisis.