A review of enteral strategies in infant short bowel syndrome: evidence-based or NICU culture?

INTRODUCTION: Short bowel syndrome (SBS) is an increasingly common condition encountered across neonatal intensive care units. Improvements in parenteral nutrition (PN), neonatal intensive care and surgical techniques, in addition to an improved understanding of SBS pathophysiology, have contributed in equal parts to the survival of this fragile subset of infants. Prevention of intestinal failure associated liver disease (IFALD) and promotion of intestinal adaptation are primary goals of all involved in the care of these patients. While enteral nutritional and pharmacological strategies are necessary to achieve these goals, there remains great variability in the application of therapeutic strategies in units that are not necessarily evidence-based. MATERIALS AND METHODS: A search of major English language medical databases (SCOPUS, Index Medicus, Medline, and the Cochrane database) was conducted for the key words short bowel syndrome, medical management, nutritional management and intestinal adaptation. All pharmacological and nutritional agents encountered in the literature search were classified based on their effects on absorptive capacity, intestinal adaptation and bowel motility that are the three major strategies employed in the management of SBS. The Oxford Center for Evidence-Based Medicine (CEBM) classification for levels of evidence was used to develop grades of clinical recommendation for each variable studied. RESULTS: We reviewed various medications used and nutritional strategies included soluble fiber, enteral fat, glutamine, probiotics and sodium supplementation. Most interventions have scientific rationale but little evidence to support their role in the management of infant SBS. While some of these agents symptomatically improve diarrhea, they can adversely influence pancreatico-biliary function or actually impair intestinal adaptation. Surgical anatomy and liver function are two important variables that should determine the selection of pharmacological and nutritional interventions. DISCUSSION: There is a paucity of research investigating optimal clinical practice in infant SBS and the little evidence available is consistently of lower quality, resulting in a wide variation of clinical practices among NICUs. Prospective trials should be encouraged to bridge the evidence gap between research and clinical practice to promote further progress in the field.

Role of trace elements in parenteral nutrition support of the surgical neonate.

BACKGROUND: Parenteral nutrition (PN) has transformed the outcome for neonates with surgical problems in the intensive care unit. Trace element supplementation in PN is a standard practice in many neonatal intensive care units. However, many of these elements are contaminants in PN solutions, and contamination levels may, in themselves, be sufficient for normal metabolic needs. Additional supplementation may actually lead to toxicity in neonates whose requirements are small. METHODS: An electronic search of the MEDLINE, Cochrane Collaboration, and SCOPUS English language medical databases was performed for the key words "trace elements," "micro-nutrients," and "parenteral nutrition additives." Studies were categorized based on levels of evidence offered, with randomized controlled trials and meta-analyses accorded the greatest importance at the apex of the data pool and case reports and animal experiments the least importance. Articles were reviewed with the primary goal of developing uniform recommendations for trace element supplementation in the surgical neonate. The secondary goals were to review the physiologic role, metabolic demands, requirements, losses, deficiency syndromes, and toxicity symptoms associated with zinc, copper, chromium, selenium, manganese, and molybdenum supplementation in PN. RESULTS: Zinc supplementation must begin at initiation of PN. All other trace elements can be added to PN 2 to 4 weeks after initiation. Copper and manganese need to be withheld if the neonate develops PN-associated liver disease. The status of chromium supplementation is currently being actively debated, with contaminant levels in PN being sufficient in most cases to meet neonatal requirements. Selenium is an important component of antioxidant enzymes with a role in the pathogenesis of neonatal surgical conditions such as necrotizing enterocolitis and bronchopulmonary dysplasia. Premature infants are often selenium deficient, and early supplementation has shown a reduction in sepsis events in this age group. CONCLUSION: Appropriate supplementation of trace elements in surgical infants is important, and levels should be monitored. In certain settings, it may be more appropriate to individualize trace element supplementation based on the predetermined physiologic need rather than using bundled packages of trace elements as is the current norm. Balance studies of trace element requirements should be performed to better establish clinical recommendations for optimal trace element dosing in the neonatal surgical population.

Congenital mesenteric defect: Description of a rare cause of distal intestinal obstruction in a neonate.

INTRODUCTION: Internal hernias are a rare cause of bowel obstruction in the neonate and present with bilious vomiting. Newborns may be at risk of loss of significant length of bowel if this rare condition is not considered in the differential diagnosis of bilious emesis. PRESENTATION OF CASE: We report a case of a twin with an internal hernia through a defect in the ileal mesentery who presented with neonatal bowel obstruction. The patient had a microcolon on the contrast enema suggesting that the likely etiology was an intra-uterine event most likely a vascular accident that prevented satisfactory meconium passage into the colon. DISCUSSION: An internal hernia is rarely considered in the differential diagnosis of distal bowel obstruction in a neonate with a microcolon. Congenital trans-mesenteric hernias constitute only 5-10% of internal hernias. True diagnosis of trans-mesenteric hernias is difficult due to lack of specific radiology or laboratory findings to confirm the suspicion. CONCLUSION: When clinical and radiological findings are not classical, rare possibilities such as an internal hernia must be considered in the differential diagnosis, to avoid catastrophic bowel loss.

Laparoscopic reduction of intussusception: an evolving therapeutic option.

INTRODUCTION: Intussusception (IS) is a common cause of bowel obstruction in the pediatric population. Traditionally, unsuccessful hydrostatic reduction has been followed by laparotomy. With the advent of minimally invasive surgery, centers have adopted laparoscopic reduction as a surgical option. We reviewed our experience with IS and investigated whether there were any advantages to performing laparoscopy over conventional laparotomy in unsuccessful air enema reduction (AE). METHODS: All the records of patients admitted from January 2001 to August 2004 with a diagnosis of IS (diagnosis code 560.0) were reviewed. Parameters investigated included age, sex, weight, radiological intervention, operative procedure, length of stay (LOS), and days to oral intake (p.o.). Statistical analysis was performed with the 2-tailed t test to compare outcomes and Fisher's exact test to assess differences in nominal frequencies. RESULTS: Seventeen males and 9 females diagnosed with IS were identified. The mean age was 2.5 years (range, 1 month to 14 years), and the average weight was 5.65 kg (range, 4.65 to 95). Twenty-three of the 26 patients (88.5%) underwent AE reduction, with success in 13 (57%). One recurred after initial successful AE, 9 failed multiple attempts at AE, and 2 attempted reductions were complicated by perforations. Fifteen patients underwent surgical reduction for unsuccessful AE or to address a pathological lead point. The success rate of laparoscopic reduction was 85%. The average time to resumption of p.o. intake for patients with successful AE was 0.5 days, and after laparoscopic reduction, the average time to p.o. intake was 1.5 days, while it was 4 days after laparotomy (P=0.05). After laparoscopic reduction, the average LOS was 6 days, but LOS was 7 days after laparotomy (P=0.66). CONCLUSION: Many children who present with IS can be treated by AE. In patients who fail AE, laparoscopy offers a safe, effective alternative to laparotomy.

Cerebral oxygenation in major pediatric trauma: its relevance to trauma severity and outcome.

INTRODUCTION: Trauma is the commonest cause of death in the pediatric population, which is prone to diffuse primary brain injury aggravated by secondary insults (eg, hypoxia, hypotension). Standard monitoring involves intracranial pressure (ICP) and cerebral perfusion pressure, which do not reflect true cerebral oxygenation (oxygen delivery [Do(2)]). We explore the merits of a brain tissue oxygen-directed critical care guide. METHODS: Sixteen patients with major trauma (Injury Severity Score, >16/Pediatric Trauma Score [PTS], <7) had partial pressure of brain tissue oxygen (Pbto(2)) monitor (Licox; Integra Neurosciences, Plainsboro, NJ) placed under local anesthesia using twist-drill craniostomy and definitive management of associated injuries. Pbto(2) levels directed therapy intensity level (ventilator management, inotrops, blood transfusion, and others). Patient demographics, short-term physiological parameters, Pbto(2), ICP, Glasgow Coma Score, trauma scores, and outcomes were analyzed to identify the patients at risk for low Do(2). RESULTS: There were 10 males and 6 females (mean age, 14 years) sustaining motor vehicle accident (14), falls (1), and assault (1), with a mean Injury Severity Score of 36 (16-59); PTS, 3 (0-7); and Revised Trauma Score, 5.5 (4-11). Eleven patients (70%) had low Do(2) (Pbto(2), <20 mm Hg) on admission despite undergoing standard resuscitation affected by fraction of inspired oxygen, Pao(2), and cerebral perfusion pressure (P = .001). Eubaric hyperoxia improved cerebral oxygenation in the low-Do(2) group (P = .044). The Revised Trauma Score (r = 0.65) showed moderate correlation with Pbto(2) and was a significant predictor for low Do(2) (P = .001). In patients with Pbto(2) of less than 20 mm Hg, PTS correlated with cerebral oxygenation (r = 0.671, P = .033). The mean 2-hour Pbto(2) and the final Pbto(2) in survivors were significantly higher than deaths (21.6 vs 7.2 mm Hg [P = .009] and 25 vs 11 mm Hg [P = .01]). Although 4 of 6 deaths were from uncontrolled high ICP, PTS and 2-hour low Do(2) were significant for roots for mortality. CONCLUSIONS: Pbto(2) monitoring allows for early recognition of low-Do(2) situations, enabling appropriate therapeutic intervention.