Hypoxic renal injury in newborns with abdominal compartment syndrome (clinical and experimental study)

Acute kidney injury post-abdominal surgery in infants: implications for prevention and management

Acute kidney injury (AKI) is common in critically ill infants and is associated with long-term sequelae including hypertension and chronic kidney disease. The etiology of AKI in infants is multifactorial. There is robust literature highlighting the risk of AKI after cardiothoracic surgery in infants. However, risk factors and outcomes for AKI in infants after abdominal surgery remains limited. This article reviews the epidemiology and association of abdominal surgery with postoperative AKI and suggests methods for AKI management and prevention. Postoperative AKI may result from hemodynamic shifts, hypoxia, exposure to nephrotoxic medications, and inflammation. Infants in the intensive care unit after intraabdominal surgeries have a unique set of risk factors that predispose them to AKI development. Prematurity, sepsis, prolonged operation time, emergent nature of the procedure, and diagnosis of necrotizing enterocolitis increase risk of AKI after intrabdominal surgeries. Prevention, early diagnosis, and management of AKI post-abdominal surgery is imperative to clinical practice. Close monitoring of urine output, serum creatinine, and fluid status is necessary in infants after abdominal surgery. A recent study suggests elevated levels of a urinary biomarker, neutrophil gelatinase-associated lipocalin (NGAL), 24 h after an abdominal procedure may improve early prediction of AKI. Identification of risk factors, avoidance of nephrotoxic medications, careful fluid balance, early detection of AKI, and maintenance of hemodynamic stability is imperative to potentially prevent and/or mitigate AKI.

Effects of extensive mobilization and tension anastomosis in anorectal reconstruction (experimental study)

PURPOSE

Anorectoplasty and pull-through procedure can be performed with extensive mobilization or tension anastomosis, which can compromise bowel blood perfusion. We aimed to analyze the hypoxia biomarker values and histopathological findings in both conditions to correlate the occurrence of anal stenosis and defecation disorders in experimental models.

METHODS

We created anorectal reconstruction models with impaired vascularization of the anorectum (group I) and tension anastomosis (group II) in rats. A third group of animals underwent sham operation (group III) and another as controls (group IV). Hypoxia biomarker values were assessed in all groups. The histopathological changes on the postoperative days 3 and 35, anal stenosis and defecation disorders on day 35 were compared.

RESULTS

Hypoxia biomarker values confirmed postoperative ischemia in groups I-III compared to control. Group I and II rats had a similarly pronounced ischemia with histopathologic changes in the anorectum on the postoperative day 3 and accompanied by severe fibrosis on day 35. Compared to the sham operation, both groups showed defecation disorders with significant anal stenoses.

CONCLUSION

Extensive rectal mobilization to about the same extent as tension anastomosis has a major impact on postoperative rectal ischemia, resulting in severe fibrotic changes in the anorectum and defecation disorders in the long term.

Intra-abdominal hypertension in neonates following congenital diaphragmatic hernia repair: Correlation with early postoperative respiratory and gastrointestinal outcomes

BACKGROUND

Increased intra-abdominal pressure (IAP) is seen in patients after congenital diaphragmatic hernia (CDH) repair owing to reduction of thoracic contents into the relatively smaller abdominal cavity. In infants, IAP ≥11 mmHg is considered intra-abdominal hypertension (IAH). We aim to determine the incidence of IAH and its relationship with duration of ventilatory support, and gastrointestinal function post CDH repair.

METHODS

We prospectively recruited all neonates who had CDH repair in four hospitals in Malaysia from June 2018 to October 2020. Intra vesical pressure was used as a proxy for IAP and was measured for 5 consecutive days post surgery. The daily median value was used for analysis. We categorized IAP as <11 mmHg (no IAH), 11-15 mmHg (IAH), and >15 mmHg (severe IAH). Incidence of IAH, its effects on the duration of ventilatory support, and gastrointestinal function were studied.

RESULTS

There were 24 neonates included in this study. They were operated between day 1 and 6 of life (median: 4 days old). IAH was detected within the first 3 days post surgery, with 83% occurring on day one. Those requiring ventilatory support for more than 3 days contributed the largest proportion of IAH (n = 17, 71%). There was strong correlation between days of IAH and duration of ventilation (p < 0.001, r = 0.70). There was moderate correlation between days of IAH and duration taken to achieve full enteral feeding (p < 0.005, r = 0.70).

CONCLUSION

IAP measurement is a safe and useful adjunct in post CDH monitoring and in predicting ventilatory support requirements and the time needed to establish feeding.

Risk factors for acute kidney injury in neonates with congenital diaphragmatic hernia

OBJECTIVE

To examine incidence of acute kidney injury (AKI), antenatal and postnatal predictors, and impact of AKI on outcomes in infants with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

Single center retrospective study of 90 CDH infants from 2009-2017. Baseline characteristics, CDH severity, possible AKI predictors, and clinical outcomes were compared between infants with and without AKI.

RESULT

In total, 38% of infants developed AKI, 44% stage 1, 29% stage 2, 27% stage 3. Lower antenatal lung volumes and liver herniation were associated with AKI. Extracorporeal life support (ECLS), diuretics, abdominal closure surgery, hypotension, and elevated plasma free hemoglobin were associated with AKI. Overall survival was 79%, 47% with AKI, and 35% with AKI on ECLS. AKI is associated with increased mechanical ventilation duration and length of stay.

CONCLUSION

AKI is common among CDH infants and associated with adverse outcomes. Standardized care bundles addressing AKI risk factors may reduce AKI incidence and severity.