Lessons Learned from Extracorporeal Membrane Oxygenation Use During the COVID-19 Pandemic

With the rise of the coronavirus disease 2019 (COVID-19) respiratory pandemic, there has been an increased need to consider the use of extracorporeal membrane oxygenation (ECMO) technology. In the early phases of the pandemic, adults constituted most of the critically ill patients, and ECMO management strategies were developed for use in this population. During the course of the pandemic, there has been a rise in the number of critically ill children infected with COVID-19. Although ECMO has been used in the care of pediatric patients for more than half a century, it has been challenging to apply the lessons learned from adult patients with COVID-19 directly to critically ill children for whom ECMO is under consideration. This article reviews ECMO technology and highlights a number of important changes in pediatric ECMO regarding those patients infected with COVID-19. [Pediatr Ann. 2022;51(7):e281-e285.].

Role of interleukin-10 in the pathogenesis of necrotizing enterocolitis

BACKGROUND

Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency in premature neonates. The pathogenesis of NEC is characterized by an intestinal epithelial injury caused by perinatal insults, leading to the activation of the mucosal innate immune system and exacerbation of the epithelial barrier damage. Cytokines play an important role in mucosal immunity. Interleukin-10 (IL-10) is an anti-inflammatory cytokine that has been shown to play a role in epithelial integrity and modulation of the mucosal immune system. We hypothesized that IL-10 may protect against the development of experimental NEC by blunting the inflammatory response in the intestine.

METHODS

Wild-type and IL-10 -/- mice underwent a NEC-inducing regimen of formula feeding in combination with hypoxia and hypothermia (FF+HH). Integrity of the gut barrier was assessed through measurement of epithelial apoptosis, tight junction disruption, and inducible nitric oxide synthase. A total of 5 μg of exogenous IL-10 was administered intraperitoneally to IL-10-/-mouse pups before the initiation of FF+HH to test dependence of gene knockout phenotype on IL-10.

RESULTS

IL-10 -/- FF+HH showed more severe morphologic and histologic changes compared with controls as evidenced by increased epithelial apoptosis, decreased junctional adhesion molecule-1 localization, and increased intestinal inducible nitric oxide synthase expression. Administration of exogenous IL-10 alleviated the mucosal injury.

CONCLUSIONS

We conclude that IL-10 plays a protective role in the pathogenesis of NEC by attenuating the degree of intestinal inflammation.

Induction of fibroblast growth factor 10 (FGF10) in the ileal crypt epithelium after massive small bowel resection suggests a role for FGF10 in gut adaptation

We have previously reported that fibroblast growth factor 10 (FGF10) is crucial for the survival and proliferation of progenitor cells during embryonic gastrointestinal development. We sought to characterize the potential role of FGF10 signaling in the adaptive response following small bowel resection. Adult wild-type and Fgf10(LacZ) mice underwent 50% small bowel resection (SBR) or sham operation. Tissues were harvested 24 or 48 hr after surgery for histology, immunohistochemistry, and in situ hybridization. After SBR, Fgf10 expression was demonstrated in the epithelium at the base of the crypts. Moreover, there was a statistically significant increase in proliferating cells and goblet cells after SBR. In vitro studies using rat intestinal epithelial crypt (IEC-6) cells exposed to medium with or without recombinant FGF10 showed increased proliferation and phosphorylation of Raf and AKT with the addition of FGF10. Our results suggest that FGF10 may play a therapeutic role in diseases involving intestinal failure.

Thoracoscopic repair of neonatal diaphragmatic hernia

INTRODUCTION

The use of minimally invasive surgery (MIS) in the neonatal population is increasing. Thoracoscopic intervention for congenital diaphragmatic hernia (CDH) is no exception. In this report, we describe our initial experience with thoracoscopic repair of left-sided diaphragmatic defects in neonates.

MATERIALS AND METHODS

We performed retrospective chart reviews on all neonates who underwent thoracoscopic repair of CDH between November 2004 and January 2008. Neonates that underwent thoracoscopic repair were physiologically stable with resolved pulmonary hypertension and minimal to moderate ventilatory support. They had no associated cardiac anomalies.

RESULTS

We identified 15 neonates with CDH who underwent thoracoscopic repair during the study period. Ten neonates underwent primary repair of the diaphragmatic defect. Five neonates with large defects required closure with a synthetic patch, which was placed thoracoscopically. The average operating room time was 134 minutes. There were no instances of intraoperative respiratory or cardiac instability. Three patients had a recurrence. One recurrence was seen after thoracoscopic patch repair. Two recurrences occurred following primary repair of left diaphragmatic hernias. There were no deaths. Follow-up has been 4-40 months.

CONCLUSIONS

Neonatal MIS for CDH should be limited to stable patients. The ideal candidate is the newborn without associated anomalies, not requiring extracorporeal membrane oxygenation, on minimal ventilatory support, and without evidence of pulmonary hypertension. It is technically possible to perform thoracoscopic repair with a patch.

Necrotizing enterocolitis--bench to bedside: novel and emerging strategies

Necrotizing enterocolitis (NEC) is a devastating illness that predominantly affects premature neonates. The mortality associated with this disease has changed very little during the last two decades. Neonates with NEC fall into two categories: those who respond to medical management alone and those who require surgical treatment. The disease distribution may be focal, multifocal, or panintestinal. Surgical treatment should therefore be based on disease presentation. Recent studies have added significant insight into our understanding of the pathogenesis of NEC. Several groups have shown that upregulation of nitric oxide plays an integral role in the development of epithelial injury in NEC. As a result, some treatment strategies have been aimed at abrogating the toxic effects of nitric oxide. In addition, several investigators have reported the cytoprotective effect of epidermal growth factor, which is found in high levels in breast milk, on the intestinal epithelium. Thus, fortification of infant formula with specific growth factors could soon become a preferred strategy to accelerate intestinal maturation in the premature neonate to prevent the development of NEC. One of the most devastating complications of NEC is the development of short bowel syndrome (SBS). The current treatment of SBS involves intestinal lengthening procedures or bowel transplantation. A novel emerging method for treating SBS involves the use of tissue-engineered intestine. In laboratory animals, tissue-engineered small intestine has been shown to be successful in treating intestinal failure. This article examines recent data regarding surgical treatment options for NEC as well as emerging treatment modalities.

Cloning and characterization of a functional peroxisome proliferator activator receptor-gamma-responsive element in the promoter of the CAP gene

c-Cbl-associating protein (CAP) is a multifunctional signaling protein that interacts with c-Cbl, facilitating the tyrosine phosphorylation of c-Cbl in response to insulin. In 3T3-L1 adipocytes and diabetic rodents, CAP gene expression is stimulated by activators of peroxisome proliferator activator receptor gamma (PPARgamma), such as thiazolidinediones (TZDs), resulting in increased insulin-stimulated c-Cbl phosphorylation. Sequence analysis of 2.5 kilobases of the 5'-flanking region of the CAP gene reveals a predicted peroxisome proliferator response element (PPRE) from -1085 to -1097. The isolated promoter was functional in 3T3 fibroblasts and adipocytes. Co-transfection of the CAP promoter with PPARgamma and retinoic acid X receptor alpha caused fold stimulation of promoter activity. The TZD rosiglitazone produced an additional 2-3-fold stimulation of the promoter. Deletion of the predicted PPRE from the CAP promoter abolished its ability to respond to rosiglitazone. Gel shift analysis of the putative PPARgamma site demonstrates direct binding of PPAR/retinoid X receptor heterodimers to the PPRE in the CAP gene. These data demonstrate that TZDs directly stimulate transcription of the CAP gene through activation of PPARgamma.