Samir K. Gadepalli

Acute kidney injury in congenital diaphragmatic hernia requiring extracorporeal life support: an insidious problem

PURPOSE Patients with congenital diaphragmatic hernia (CDH) requiring extracorporeal life support (ECLS) are at increased risk for acute kidney injury (AKI). We hypothesized that AKI would be associated with increased mortality. We further hypothesized that vasopressor requirement, nephrotoxic medications, and infections would be associated with AKI. METHODS We performed a retrospective chart review in all patients with CDH requiring ECLS from 1999 to 2009 (n = 68). Patient variables that could potentiate renal failure were collected. We used a rise in creatinine from baseline by the RIFLE (risk, 1.5×; injury, 2×; failure, 3×; loss; and end-stage renal disease) criteria to define AKI. Statistical analysis was performed via SPSS (SPSS, Chicago, IL) using Student t test and χ(2) analysis, with P < .05 being considered significant. RESULTS Survival to hospital discharge was 37 (54.4%) of 68. Acute kidney injury was identified in 48 (71%) of 68 patients, with 15 (22% of all patients) qualifying as injury and 33 (49% of all patients) qualifying as failure by the RIFLE criteria. Patients who qualified as failure by the RIFLE criteria had a significant decrease in survival (27.3% with failure vs 80% without failure; P = .001). Patients who qualified as failure also had increased length of ECLS (314 ± 145 vs 197 ± 115 hours; P = .001) and decreased ventilator-free days in the first 60 days (1.39 ± 5.3 vs 20.17 ± 17.4 days; P = .001). There was no significant difference in survival when patients qualified as risk or injury. CONCLUSIONS This is the first report using a systematic definition of AKI in patients with CDH on ECLS. There is a high incidence of AKI in these patients, and when it progresses to failure, it is associated with higher mortality, increased ECLS duration, and increased ventilator days. This highlights the importance of recognizing AKI in patients with CDH requiring ECLS and the potential benefit of preventing progression of AKI or early intervention.

Vertical expandable prosthetic titanium rib device insertion: Does it improve pulmonary function?

PURPOSE Vertical expandable prosthetic titanium rib (VEPTR) insertion and expansion has been advocated to increase thoracic volume and pulmonary function in patients with thoracic insufficiency syndrome. We reviewed our experience with VEPTR implantation to determine if lung function and growth is augmented, to determine the childrens functional status, and if the scoliosis is controlled. METHODS From 2006 to 2010, 29 insertions and 57 expansions were performed in 26 patients at our institution. Demographic data were reviewed in conjunction with complications, scoliosis angles, pulmonary function tests (PFTs), and computed tomography-guided 3D reconstructions to determine lung volumes; and quality of life scores were determined using a modified Scoliosis Research Society (SRS) questionnaire preoperatively and postoperatively. The groups were also stratified by age (because of lung growth potential), disease (congenital or infantile scoliosis, Jeune syndrome, neuromuscular, other structural thoracic disorders), and sex. Analyses using SPSS (SPSS, Chicago, Ill) were performed with P < .05 considered significant. RESULTS Each patient underwent 3.03 ± 1.8 surgeries, spending 0.97 ± 1.8 days in the intensive care unit and 4.41 ± 6 days in the hospital for each procedure. Mean age was 90.7 ± 41 months. Of the 36 complications, most were because of infection (12), half requiring operative repair (hardware removal). The average PFT percent predicted values for forced expiratory volume in 1 second, forced vital capacity, and RV were 54.6 ± 22, 58.1 ± 24, and 145.3 ± 112, respectively, preoperatively and 51.8 ± 20, 55.9 ± 20, and 105.6 ± 31, respectively, postoperatively. The lung volumes measured by computed tomography when corrected for age do not increase significantly postoperatively. The mean Cobb measurement for the preoperative major curves was 64.7° and postoperatively was 46.1° for those curves measured preoperatively, for a 29% curve improvement. All postoperative curves had a mean of 56.4° and 58.1° at final follow-up, a 3% curve increase. The SRS scores for patients remained unchanged and no statistical difference was seen from preoperative to postoperative values. No statistically significant difference was seen in complications, PFT (forced expiratory volume in 1 second, forced vital capacity, RV), lung volumes, scoliosis angles, and SRS scores between sex, age, and disease categories. CONCLUSION There was mild improvement in scoliosis angles but no improvement in lung function and volume. Scoliosis Research Society scores indicate that the children have near normal function both before and after VEPTR placement. Pulmonary function, lung volume, and patient subjective assessments did not increase dramatically after VEPTR placement, although scoliosis angles improved.

Equivocal Pediatric Appendicitis: Unenhanced MR Imaging Protocol for Nonsedated Children—A Clinical Effectiveness Study

PURPOSE To determine retrospectively the clinical effectiveness of an unenhanced magnetic resonance (MR) imaging protocol for evaluation of equivocal appendicitis in children. MATERIALS AND METHODS Institutional review board approval was obtained. Pediatric patients (≤18 years old) underwent unenhanced MR imaging and contrast material-enhanced computed tomography (CT) of the appendix between December 2013 and November 2014 and December 2012 and November 2013, respectively, within 24 hours after an abdominal ultrasonographic examination with results equivocal for appendicitis. Pertinent MR imaging and CT reports were reviewed for visibility of the appendix, presence of appendicitis and appendiceal perforation, and establishment of an alternative diagnosis. Surgical reports, pathologic reports, and 30-day follow-up medical records were used as reference standards. Diagnostic performance with MR imaging and CT was calculated with 95% confidence intervals (CIs) for diagnosis of appendicitis and appendiceal perforation. The Fisher exact test was used to compare proportions; the Student t test was used to compare means. RESULTS Diagnostic performance with MR imaging was comparable to that with CT for equivocal pediatric appendicitis. For MR imaging (n = 103), sensitivity was 94.4% (95% CI: 72.7%, 99.9%) and specificity was 100% (95% CI: 95.8%, 100%); for CT [n = 58], sensitivity was 100% (95% CI: 71.5%, 100%), specificity was 97.9% (95% CI: 88.7%, 100%). Diagnostic performance with MR imaging and CT also was comparable for detection of appendiceal perforation, with MR imaging (n = 103) sensitivity of 90.0% (95% CI: 55.5%, 99.8%) and specificity of 85.7% (95% CI: 42.1%, 99.6%) and CT (n = 58) sensitivity of 75.0% (95% CI: 19.4%, 99.4%) and specificity of 85.7% (95% CI: 42.1%, 99.6%). The proportion of examinations with identifiable alternative diagnoses was similar at MR imaging to that at CT (19 of 103 [18.4%] vs eight of 58 [13.8%], respectively; P = .52). The proportion of appendixes seen at MR imaging and at CT also was similar (77 of 103 [74.8%] vs 50 of 58 [86.2%], respectively; P = .11). CONCLUSION Unenhanced MR imaging is sensitive and specific for the diagnosis of equivocal appendicitis in nonsedated pediatric patients.

Perioperative management and outcomes of esophageal atresia and tracheoesophageal fistula

BACKGROUND/PURPOSE Esophageal atresia/tracheoesophageal fistula (EA/TEF) is a rare congenital anomaly lacking contemporary data detailing patient demographics, medical/surgical management and outcomes. Substantial variation in the care of infants with EA/TEF may affect both short- and long-term outcomes. The purpose of this study was to characterize the demographics, management strategies and outcomes in a contemporary multi-institutional cohort of infants diagnosed with EA/TEF to identify potential areas for standardization of care. METHODS A multi-institutional retrospective cohort study of infants with EA/TEF treated at 11 childrens hospitals between 2009 and 2014 was performed. Over the 5year period, 396 cases were identified in the 11 centers (7±5 per center per year). All infants with a diagnosis of EA/TEF made within 30days of life who had surgical repair of their defect defined as esophageal reconstruction with or without ligation of TEF within the first six months of life were included. Demographic, operative, and outcome data were collected and analyzed to detect associations between variables. RESULTS Prenatal suspicion or diagnosis of EA/TEF was present in 53 (13%). The most common anatomy was proximal EA with distal TEF (n=335; 85%) followed by pure EA (n=27; 7%). Clinically significant congenital heart disease (CHD) was present in 137 (35%). Mortality was 7.5% and significantly associated with CHD (p<0.0001). Postoperative morbidity occurred in 62% of the population, including 165 (42%) cases with anastomotic stricture requiring intervention, anastomotic leak in 89 (23%), vocal cord paresis/paralysis in 26 (7%), recurrent fistula in 19 (5%), and anastomotic dehiscence in 9 (2%). Substantial variation in practice across our institutions existed: bronchoscopy prior to repair was performed in 64% of cases (range: 0%-100%); proximal pouch contrast study in 21% (0%-69%); use of interposing material between the esophageal and tracheal suture lines in 38% (0%-69%); perioperative antibiotics ≥24h in 69% (36%-97%); and transanastomotic tubes in 73% (21%-100%). CONCLUSION Contemporary treatment of EA/TEF is characterized by substantial variation in perioperative management and considerable postoperative morbidity and mortality. Future studies are planned to establish best practices and clinical care guidelines for infants with EA/TEF. LEVEL OF EVIDENCE Type of study: Treatment study. Level IV.

Development of an Artificial Placenta IV: 24-Hour Venovenous Extracorporeal Life Support in Premature Lambs

An extracorporeal artificial placenta would change the paradigm of treating extremely premature infants. We hypothesized that a venovenous extracorporeal life support (VV-ECLS) artificial placenta would maintain fetal circulation, hemodynamic stability, and adequate gas exchange for 24 hours. A near-term neonatal lamb model (130 days; term = 145 days) was used (n = 9). The right jugular vein was cannulated for VV-ECLS outflow, and an umbilical vein was used for inflow. The circuit included a peristaltic roller pump and a 0.5 m2 hollow fiber oxygenator. Lambs were maintained on VV-ECLS in an “amniotic bath” for up to 24 hours. Five of nine fetuses survived for 24 hours. In the survivors, average mean arterial pressure was 69 ± 10 mm Hg for the first 4 hours and 36 ± 8 mm Hg for the remaining 20 hours. The mean fetal heart rate was 202 ± 30. Mean VV-ECLS flow was 94 ± 20 ml/kg/min. Using a gas mixture of 50% O2/3% CO2 and sweep flow of 1–2 L/min, the mean pH was 7.27 ± 0.09, with Po2 of 35 ± 12 mm Hg and Pco2 of 48 ± 12 mm Hg. Necropsy revealed a patent ductus arteriosus in all cases, and there was no gross or microscopic intracranial hemorrhage. Complications in failed attempts included technically difficult cannulation and multisystem organ failure. Future studies will enhance stability and address the factors necessary for long-term support.

Small Bowel Diameter in Short Bowel Syndrome as a Predictive Factor for Achieving Enteral Autonomy

Children with short bowel syndrome commonly have dilated small bowel. We found that the extent of dilation was associated with bowel length and that both were related to achieving enteral autonomy.

Improving central line infection rates in the neonatal intensive care unit: Effect of hospital location, site of insertion, and implementation of catheter-associated bloodstream infection protocols

INTRODUCTION Catheter associated blood stream infections (CABSIs) are morbid and expensive for all ages, including neonates. Thus far, the impact of CABSI prevention protocols, such as insertion and maintenance bundles, in the neonatal intensive care unit (NICU) is largely unknown. We hypothesized that lines placed in the operating room (OR) would have a lower infection rate due to established insertion protocols and a more sterile environment. METHODS A retrospective chart review of NICU patients who received a percutaneous or tunneled central venous catheter between 2005 and 2012 was performed. ECMO cannulas, PICC and umbilical catheters were excluded. Variables of interest included demographics, anatomical site, hospital location, line days, and line infection. Line infection was defined as a positive blood culture drawn through the catheter. RESULTS A total of 368 catheters were placed in 285 NICU patients. Majority of catheters (65.5%) were placed in OR. Saphenous and femoral veins were most common anatomical sites (50.8%). Twenty-eight catheters were infected (7.6%). After adjusting for preoperative antibiotics, anatomical site, and SNAPPE-II scores, lines placed in OR were three times less likely to become infected (Odds Ratio=0.32, p=0.038). Although implementation of CABSI prevention protocols resulted in statistically significant reductions in infection (Odds Ratio=0.4, p=0.043), lines placed in the OR remained less likely to become infected. CONCLUSIONS NICU line infection rates decreased with implementation of CABSI prevention protocols. Despite this implementation, catheters placed in the NICU continued to have higher infection rates. As a result, when patient status allows it, we recommend that central lines in newborns be placed in the operating room.

Challenging surgical dogma in the management of proximal esophageal atresia with distal tracheoesophageal fistula: Outcomes from the Midwest Pediatric Surgery Consortium

PURPOSE Perioperative management of infants with esophageal atresia and tracheoesophageal fistula (EA/TEF) is frequently based on surgeon experience and dogma rather than evidence-based guidelines. This study examines whether commonly perceived important aspects of practice affect outcome in a contemporary multi-institutional cohort of patients undergoing primary repair for the most common type of esophageal atresia anomaly, proximal EA with distal TEF. METHODS The Midwest Pediatric Surgery Consortium conducted a multicenter, retrospective study examining selected outcomes on infants diagnosed with proximal EA with distal TEF who underwent primary repair over a 5-year period (2009-2014), with a minimum 1-year follow up, across 11 centers. RESULTS 292 patients with proximal EA and distal TEF who underwent primary repair were reviewed. The overall mortality was 6% and was significantly associated with the presence of congenital heart disease (OR 4.82, p=0.005). Postoperative complications occurred in 181 (62%) infants, including: anastomotic stricture requiring intervention (n=127; 43%); anastomotic leak (n=54; 18%); recurrent fistula (n=15; 5%); vocal cord paralysis/paresis (n=14; 5%); and esophageal dehiscence (n=5; 2%). Placement of a transanastomotic tube was associated with an increase in esophageal stricture formation (OR 2.2, p=0.01). Acid suppression was not associated with altered rates of stricture, leak or pneumonia (all p>0.1). Placement of interposing prosthetic material between the esophageal and tracheal suture lines was associated with an increased leak rate (OR 4.7, p<0.001), but no difference in the incidence of recurrent fistula (p=0.3). Empiric postoperative antibiotics for >24h were used in 193 patients (66%) with no difference in rates of infection, shock or death when compared to antibiotic use ≤24h (all p>0.3). Hospital volume was not associated with postoperative complication rates (p>0.08). Routine postoperative esophagram obtained on day 5 resulted in no delayed/missed anastomotic leaks or a difference in anastomotic leak rate as compared to esophagrams obtained on day 7. CONCLUSION Morbidity after primary repair of proximal EA and distal TEF patients is substantial, and many common practices do not appear to reduce complications. Specifically, this large retrospective series does not support the use of prophylactic antibiotics beyond 24h and empiric acid suppression may not prevent complications. Use of a transanastomotic tube was associated with higher rates of stricture, and interposition of prosthetic material was associated with higher leak rates. Routine postoperative esophagram can be safely obtained on day 5 resulting in earlier initiation of oral feeds. STUDY TYPE Treatment study. LEVEL OF EVIDENCE III.

Evidence-based management of chylothorax in infants

PURPOSE Management guidelines for infants with chylothorax lack substantial evidence. We sought to identify variables that impact outcomes in these patients in order to develop an evidence-based management algorithm. METHODS We retrospectively reviewed the medical records of all infants diagnosed with chylothorax from June 2005 to December 2014 at our institution. Data collected included demographics, chest tube output (CTO), medical and dietary interventions, surgical procedures, and absolute lymphocyte count (ALC). Outcomes analyzed included death, sepsis, necrotizing enterocolitis (NEC), requiring surgery, and success of therapy, defined as CTO decrease by >50% within 7days. RESULTS Of 178 neonates with chylothorax, initial therapy was high medium chain triglyceride (MCT) feedings in 106 patients, nothing by mouth (NPO), total parenteral nutrition (TPN) in 21, and NPO/TPN plus octreotide in 45. Octreotide use in addition to NPO/TPN revealed no significant differences in any outcome including success (47% vs. 43%, p=0.77). Initial CTO and ALC correlated with needing surgery (p=0.002 and p=0.006, respectively), and with death (p=0.028 and p=0.043, respectively). ALC also correlated with sepsis (p<0.001). CONCLUSIONS Octreotide has no advantage over NPO/TPN alone in infants with chylothorax. CTO and ALC predict requiring surgery. We propose a management guideline based on CTO and ALC without a role for octreotide. TYPE OF STUDY Retrospective case-control study. LEVEL OF EVIDENCE 3.

Analysis of risk factors contributing to morbidity from gastrojejunostomy feeding tubes in children

PURPOSE The purpose of this study was to define morbidity from gastrojejunostomy tube (GJT) placement in children. METHODS A retrospective single-center 5-year review of GJT placement in children was performed. Age, weight, prior surgery, indication, type of GJT, and complications (GJT replacement, wound complications, and perforation) were recorded. Logistic regression for morbidity was performed. RESULTS 142 children underwent 394 GJT placements at a median age of 2.7years (range 5 weeks-18years). The most common indications were failure to thrive (62%) and reflux (25%). Among the 296 GJT replacements, the most common reason was tube dislodgement (30%). Risk factors for replacement, which occurred at a median interval of 12 weeks (range 2days-2.4years), were peristomal complaint (OR=5.4, p=0.02) and prior GJT replacement (OR=1.8, p=0.03). In all, 7 (5%) jejunal perforations occurred at a median of 3 days (range 0-21 days) from GJT placement. Patients with perforation had a median weight of 4.6kg (range 3-11.2kg) and age of 3.9months (range 8 weeks-2.1years). Lower weight (p<0.01) and younger age (p=0.02) predicted perforation, with those weighing less than 6kg (OR=51.9, p<0.001) or younger than 6months (OR=28.6, p<0.01) at highest risk. CONCLUSIONS GJT placement has a significant risk of recurrent dislodgement and the highest risk of perforation in children weighing less than 6kg or younger than 6months. Alternate feeding options should be strongly considered in this vulnerable population.