Joseph T. Church

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.

Vascular Access in the Pediatric Population

Vascular access procedures are an important and frequent component of the day-to-day practice of the pediatric surgeon. Most access procedures can be performed percutaneously via Seldinger or modified Seldinger technique and are aided by technology, such as ultrasound and fluoroscopy. Complications, such as infection, do occur, and the pediatric surgeon should be able to diagnose and treat these when they arise. The indications, techniques, and complications of vascular access are covered in this article.

Pushing the boundaries of ECLS: Outcomes in <34 week EGA neonates

PURPOSE Extracorporeal life support (ECLS) is usually reserved for infants ≥34weeks estimated gestational age (EGA) owing to concerns about increased mortality and incidence of intracranial hemorrhage (ICH). We sought to characterize survival, rates of ICH, and complications in <34week EGA neonates placed on ECLS. METHODS 752 neonates of EGA 29-34weeks were identified in the Extracorporeal Life Support Organization (ELSO) Registry (1976-2008). Data analyzed included birthweight, survival, pre-ECLS conditions, ventilatory parameters and complications (including ICH and other neurological outcomes). Data were compared using t-test, Chi-square and logistic regression analyses. RESULTS When compared to survival rates of 34week EGA neonates (58%), survival was statistically different for 29-33week EGA (48%, p=0.05). No significant difference in ICH incidence was seen between the 29-33week and 34week groups (21% vs. 17%, respectively), but a significant difference was seen in the incidence of cerebral infarct between groups (22% for 29-33weeks vs. 16% for 34weeks; p=0.03). ICH and survival did not correlate with EGA during logistic regression analysis. CONCLUSIONS Though rates of survival and cerebral infarction were worse at 29-33weeks EGA compared with 34weeks, these differences were modest and may be clinically acceptable. This suggests that EGA<34weeks may not be an absolute contraindication to use of ECLS. LEVEL OF EVIDENCE III.

Methylene blue for burn-induced vasoplegia: Case report and review of literature

We report the use of a single dose of methylene blue in a patient with burn-induced vasoplegia refractory to fluids, vasopressors, and steroids. Administration of methylene blue allowed for cessation of epinephrine infusion within 2 hours of administration, and reduction in excessive fluid resuscitation. The patients clinical course continued for 2 months and was complicated by severe acute respiratory distress syndrome, pneumonia, septic shock, poor skin graft adherence, renal failure requiring continuous renal replacement therapy, cutaneous mucormycosis, and ultimately, withdrawal of care and death. Despite the eventual outcome, this is the longest reported survival following methylene blue administration for vasoplegia secondary to burn injury.

Perfluorocarbons Prevent Lung Injury and Promote Development during Artificial Placenta Support in Extremely Premature Lambs

Background: Extremely premature neonates suffer high morbidity and mortality. An artificial placenta (AP) using extracorporeal life support (ECLS) is a promising therapy. Objectives: We hypothesized that intratracheal perfluorocarbon (PFC) instillation during AP support would reduce lung injury and promote lung development relative to intratracheal amniotic fluid or crystalloid. Methods: Lambs at an estimated gestational age (EGA) 116–121 days (term 145 days) were placed on venovenous ECLS with jugular drainage and umbilical vein reinfusion and intubated. Airways were managed by the instillation of amniotic fluid and tracheal occlusion (TO; n = 4), or lactated Ringer’s (LR; n = 4) or perfluorodecalin (a PFC) without occlusion (n = 4). After 7 days, the animals were sacrificed. Early (EGA 116–121 days) and late (EGA 125–131 days) tissue control lambs were delivered and sacrificed. Lungs were formalin-inflated to 30 cm H2O and sectioned for histology. Injury was scored by an unbiased pathologist. Slides were immunostained for PDGFR-α and α-actin; development was quantified by the area fraction of double-positive tips. Surfactant protein-C (SP-C) concentration in bronchoalveolar lavage fluid was quantified using ELISA. Results: Total injury scores were lower in PFC lungs (1.8 ± 1.7) than in TO (6.5 ± 2.1; p = 0.01) and LR lungs (5.5 ± 2.4; p = 0.01). The area fraction of double-positive alveolar tips appeared higher in PFC lungs than in TO lungs (0.18 ± 0.007 vs. 0.008 ± 0.004; p = 0.07). SP-C concentration was higher in PFC lungs than in TO lungs (37.9 ± 7.6 vs. 20.0 ± 5.4 pg/mL; p = 0.005), and both early (12.4 ± 1.7 g/mL; p = 0.007) and late tissue control lungs (15.1 ± 5.0 pg/mL; p = 0.0008). Conclusion: During AP support, intratracheal PFC prevents lung injury and promotes normal lung development better than crystalloid or amniotic fluid with TO.

Effects of an artificial placenta on brain development and injury in premature lambs

PURPOSE We evaluated whether brain development continues and brain injury is prevented during Artificial Placenta (AP) support utilizing extracorporeal life support (ECLS). METHODS Lambs at EGA 118days (term=145; n=4) were placed on AP support (venovenous ECLS with jugular drainage and umbilical vein reinfusion) for 7days and sacrificed. Early (EGA 118; n=4) and late (EGA 127; n=4) mechanical ventilation (MV) lambs underwent conventional MV for up to 48h and were sacrificed, and early (n=5) and late (n=5) tissue control (TC) lambs were sacrificed at delivery. Brains were harvested, formalin-fixed, rehydrated, and studied by magnetic resonance imaging (MRI). The gyrification index (GI), a measure of cerebral folding complexity, was calculated for each brain. Diffusion-weighted imaging was used to determine fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in multiple structures to assess white matter (WM) integrity. RESULTS No intracranial hemorrhage was observed. GI was similar between AP and TC groups. ADC and FA did not differ between AP and late TC groups in any structure. Compared to late MV brains, AP brains demonstrated significantly higher ADC (0.45±0.08 vs. 0.27±0.11, p=0.02) and FA (0.61±0.04 vs. 0.44±0.05; p=0.006) in the cerebral peduncles. CONCLUSIONS After 7days of AP support, WM integrity is preserved relative to mechanical ventilation. TYPE OF STUDY Research study.

Neurodevelopmental outcomes in CDH survivors: A single institution's experience

PURPOSE Survivors of congenital diaphragmatic hernia (CDH) face high morbidity. We studied the neurodevelopmental outcomes of CDH survivors at a single institution. METHODS CDH survivors born July 2006-March 2016 at a free-standing childrens hospital were reviewed. Neurodevelopment was assessed using the Peabody Developmental Motor Scales (PDMS-2) broken into gross, fine, and total motor quotients. Data collected included prenatal variables (liver herniation, defect laterality, observed:expected total fetal lung volume (o:eTFLV) on MRI), birth demographics (sex, race, estimated gestational age (EGA), birth weight (BtWt), 5 min APGAR, associated anomalies), and therapies/hospital course (HFOV/HFJV, ECMO, timing of repair, pulmonary hypertension (PHTN) severity, length of stay, ventilator days). Variables were analyzed using mixed linear modeling. RESULTS Sixty-eight children were included. Most patients had left-sided CDH (55/68, 81%) without liver herniation (42/68, 62%). ECMO utilization was 25/68 (37%). The mean [95% confidence interval] gross motor quotient for the entire cohort was 87 [84-91], fine motor quotient was 92 [88-96], and total motor quotient was 88 [84-93], representing below average, average, and below average functioning, respectively. o:eTFLV predicted fine motor quotient among prenatal variables. Associated anomalies and ECMO use predicted all quotients in the final model. CONCLUSIONS Associated anomalies and ECMO use predict neurodevelopmental delay in CDH survivors. TYPE OF STUDY Retrospective observational study; Prognostic. LEVEL OF EVIDENCE II.

Gastrointestinal mucosal development and injury in premature lambs supported by the artificial placenta

BACKGROUND An Artificial Placenta (AP) utilizing extracorporeal life support (ECLS) could revolutionize care of extremely premature newborns, but its effects on gastrointestinal morphology and injury need investigation. METHODS Lambs (116-121days GA, term=145; n=5) were delivered by C-section, cannulated for ECLS, had total parenteral nutrition (TPN) provided, and were supported for 7days before euthanasia. Early and Late Tissue Controls (ETC, n=5 and LTC, n=5) delivered at 115-121days and 125-131days, respectively, were immediately sacrificed. Standardized jejunal samples were formalin-fixed for histology. Crypt depth (CD), villus height (VH), and VH:CD ratios were measured. Measurements also included enterocyte proliferation (Ki-67), Paneth cell count (Lysozyme), and injury scores (H&E). ANOVA and Chi Square were used with p<0.05 considered significant. RESULTS CD, VH, and VH:CD were similar between groups (p>0.05). AP demonstrated more enterocyte proliferation (95.7±21.8) than ETC (49.4±23.4; p=0.003) and LTC (66.1+11.8; p=0.04), and more Paneth cells (81.7±17.5) than ETC (41.6±7.0; p=0.0005) and LTC (40.7±8.2, p=0.0004). Presence of epithelial injury and congestion in the bowel of all groups were not statistically different. No villus atrophy or inflammation was present in any group. CONCLUSIONS This suggests preserved small bowel mucosal architecture, high cellular turnover, and minimal evidence of injury. STUDY TYPE Research paper/therapeutic potential. LEVEL OF EVIDENCE N/A.

Avalon catheters in pediatric patients requiring ECMO: Placement and migration problems

PURPOSE The Avalon dual-lumen venovenous catheter has several advantages, but placement techniques and management have not been adequately addressed in the pediatric population. We assessed our institutional outcomes and complications using the Avalon catheter in children. METHODS We reviewed all pediatric patients who had Avalon catheters placed for respiratory failure at our institution, excluding congenital heart disease patients, from April 2009 to March 2016. All patients were managed using our standard ECMO protocol, and cannula position was followed by daily chest x-ray and intermittent echocardiography (ECHO). Data included demographics, diagnosis, PRISM3 predicted mortality, ECMO duration, complications, and survival. The primary outcome was the need for catheter repositioning. RESULTS Twenty-five patients were included, with mean age 8.3±6.9years and 15±22days of ECMO support. Overall survival was 68% (17/25). Fourteen patients (56%) underwent placement with fluoroscopy in addition to ultrasound and ECHO, primarily after 2013. Overall, thirteen patients (52%) had problems with cannula malposition. 9 of these (69%) required cannula repositioning. Three of 14 (21%) cannulas placed with fluoroscopy required repositioning, compared to 7/11 (64%) placed without fluoroscopy (p=0.05). CONCLUSIONS Complications are common with the Avalon catheter in children. Safe percutaneous access requires ultrasound guidance, and use of intraoperative fluoroscopy in addition to echocardiography decreases malposition rates. LEVEL OF EVIDENCE IV (Prognosis study).

Ultrasound-guided gastrostomy tube placement: A case series

PURPOSE Gastrostomy tubes (G-tubes) can be placed utilizing a variety of techniques. Here we present a case series to demonstrate feasibility of a novel method, ultrasound-guided G-tube placement (USGTP). METHODS All cases of USGTP at our institution from September 2015-August 2016 were reviewed. Data included demographics, operative time, complications, time to first feeding, and 30-day readmissions. All steps of the procedure were carried out using ultrasound guidance, resulting in placement of a low-profile G-tube. RESULTS Twelve patients underwent USGTP. Median age at operation was 2.6years (IQR 0.9-5.3) and median weight 9.9kg (IQR 7.2-18.4). Median operative time was 27min. (IQR 20-44). First feeding occurred 8.8±2.9h after the procedure. The second patient in the series experienced the only operative complication. In this case, a linear probe was used with insufficient gastric distension, resulting in placement of the tube through a fold in the stomach wall. This was recognized and remedied intraoperatively. This prompted successful technique modification for future USGTPs. Only one patient was readmitted within 30days, and this was related to urinary retention, an underlying problem. CONCLUSION US-guided G-tube placement appears initially to be safe, efficient and effective. Advantages include good anatomical delineation, a single incision, initial placement of a low-profile G-tube, and avoidance of endoscopy, laparoscopy, and radiation. This report illustrates feasibility of USGTP paving the way for further investigation and comparison to other existing gastrostomy insertion methods. LEVEL OF EVIDENCE IV.