Decreased ß-catenin Protein in Lungs From Human Congenital Diaphragmatic Hernia Archival Pathology Specimens: A Case-control Study.

BACKGROUND: Lung hypoplasia contributes to congenital diaphragmatic hernia (CDH) associated morbidity and mortality. Changes in lung wingless-type MMTV integration site family member (Wnt)-signalling and its downstream effector beta-catenin (CTNNB1), which acts as a transcription coactivator, exist in animal CDH models but are not well characterized in humans. We aim to identify changes to Wnt-signalling gene expression in human CDH lungs and hypothesize that pathway expression will be lower than controls. METHODS: We identified 51 CDH cases and 10 non-CDH controls with archival formalin-fixed paraffin-embedded (FFPE) autopsy lung tissue from 2012 to 2022. 11 liveborn CDH cases and an additional two anterior diaphragmatic hernias were excluded from the study, leaving 38 CDH cases. Messenger ribonucleic acid (mRNA) expression of Wnt-signalling effectors WNT2B and CTNNB1 was determined for 19 CDH cases and 9 controls. A subset of CDH cases and controls lung sections were immunostained for ß-catenin. Clinical variables were obtained from autopsy reports. RESULTS: Median gestational age was 21 weeks. 81% (n = 31) of hernias were left-sided. 47% (n = 18) were posterolateral. Liver position was up in 81% (n = 31) of cases. Defect size was Type C or D in 58% (n = 22) of cases based on autopsy photos, and indeterminable in 42% (n = 16) of cases. WNT2B and CTNNB1 mRNA expression did not differ between CDH and non-CDH lungs. CDH lungs had fewer interstitial cells expressing ß-catenin protein than non-CDH lungs (13.2% vs 42.4%; p = 0.006). CONCLUSION: There appear to be differences in the abundance and/or localization of ß-catenin proteins between CDH and non-CDH lungs. LEVEL OF EVIDENCE: Level III. TYPE OF STUDY: Case-Control Study.

The metabolic and lipidomic profiling of the effects of tracheal occlusion in a rabbit model of congenital diaphragmatic hernia.

PURPOSE: Fetal tracheal occlusion (TO) reverses the pulmonary hypoplasia associated with congenital diaphragmatic hernia (CDH), but its mechanism of action remains poorly understood. 'Omic' readouts capture metabolic and lipid processing function, which aid in understanding CDH and TO metabolic mechanisms. METHODS: CDH was created in fetal rabbits at 23 days, TO at 28 days and lung collection at 31 days (Term ∼32 days). Lung-body weight ratio (LBWR) and mean terminal bronchiole density (MTBD) were determined. In a cohort, left and right lungs were collected, weighed, and samples homogenized, and extracts collected for non-targeted metabolomic and lipidomic profiling via LC-MS and LC-MS/MS, respectively. RESULTS: LBWR was significantly lower in CDH while CDH + TO was similar to controls (p = 0.003). MTBD was significantly higher in CDH fetuses and restored to control and sham levels in CDH + TO (p < 0.001). CDH and CDH + TO resulted in significant differences in metabolome and lipidome profiles compared to sham controls. A significant number of altered metabolites and lipids between the controls and CDH groups and the CDH and CDH + TO fetuses were identified. Significant changes in the ubiquinone and other terpenoid-quinone biosynthesis pathway and the tyrosine metabolism pathway were observed in CDH + TO. CONCLUSION: CDH + TO reverses pulmonary hypoplasia in the CDH rabbit, in association with a specific metabolic and lipid signature. A synergistic untargeted 'omics' approach provides a global signature for CDH and CDH + TO, highlighting cellular mechanisms among lipids and other metabolites, enabling comprehensive network analysis to identify critical metabolic drivers in disease pathology and recovery. TYPE OF STUDY: Basic Science, Prospective. LEVEL OF EVIDENCE: II.

Comparison of drugs used for intubation of pediatric trauma patients.

PURPOSE: Rapid sequence intubation (RSI) drugs, such as propofol, affect clinical outcomes, but this has not been examined in the pediatric population. This descriptive study compares the outcomes associated with intubation drugs used in pediatric traumatic brain injury (TBI) patients. METHODS: A retrospective chart review and descriptive analysis of intubated TBI patients, ages 0-17, admitted to Children's Hospital London Health Sciences Centre (LHSC) from January 2006-December 2016 was performed. RESULTS: Out of 259 patients intubated, complete data was available for 107 cases. Average injury severity score was 28; 46 were intubated at LHSC, 55 at primary care site, and 6 on scene. Intubation attempts were recorded in 87 of 107 paper charts. First-pass intubation success rate was 88.5%. Propofol (n = 21), midazolam (n = 31), etomidate (n = 13), and ketamine (n = 7) were the most commonly used intubation drugs. Paralytics were used in 50% of patients. Following use of propofol, Pediatric Adjusted Shock Index was increased as a result of worsening hypotension. Mean total hospital length of stay was 21 days with 7.5 days in ICU. Survival was 87%. CONCLUSION: Great variability exists in the use of induction agents and paralytics for RSI. Propofol was commonly used and is potentially associated with poorer clinical outcomes. TYPE OF STUDY: Retrospective. LEVEL OF EVIDENCE: IV.

The effects of tracheal occlusion on Wnt signaling in a rabbit model of congenital diaphragmatic hernia.

PURPOSE: Tracheal occlusion (TO) reverses pulmonary hypoplasia (PH) in congenital diaphragmatic hernia (CDH), but its mechanism of action remains poorly understood. Wnt signaling plays a critical role in lung development, but few studies exist. The purpose of our study was to a) confirm that our CDH rabbit model produced PH which was reversed by TO and b) determine the effects of CDH +/- TO on Wnt signaling. METHODS: CDH was created in fetal rabbits at 23 days, TO at 28 days, and lung collection at 31 days. Lung body weight ratio (LBWR) and mean terminal bronchiole density (MTBD) were determined. mRNA and miRNA expression was determined in the left lower lobe using RT-qPCR. RESULTS: Fifteen CDH, 15 CDH + TO, 6 sham CDH, and 15 controls survived and were included in the study. LBWR was low in CDH, while CDH + TO was similar to controls (p = 0.003). MTBD was higher in CDH fetuses and restored to control levels in CDH + TO (p < 0.001). Reference genes TOP1, SDHA, and ACTB were consistently expressed within and between treatment groups. miR-33 and MKI67 were increased, and Lgl1 was decreased in CDH + TO. CONCLUSION: TO reversed pulmonary hypoplasia and stimulated early Wnt signaling in CDH fetal rabbits. TYPE OF STUDY: Basic science, prospective. LEVEL OF EVIDENCE: II.

Cost analysis of nonoperative management of acute appendicitis in children.

PURPOSE: The purpose of this study was to determine if nonoperative management of acute appendicitis in children is more cost effective than appendectomy. METHODS: A retrospective review of children (6-17years) with acute appendicitis treated nonoperatively (NOM) from May 2012 to May 2015 was compared to similar patients treated with laparoscopic appendectomy (OM) (IRB#107535). Inclusion criteria included symptoms ≤48h, localized peritonitis, and ultrasound confirmation of acute appendicitis. Variables analyzed included failure rates, complications, length of stay (LOS), and cost analysis. RESULTS: 26 NOM patients (30% female, mean age 12) and 26 OM patients (73% female, mean age 11) had similar median initial LOS (24.5h (NOM) vs 16.5h (OM), p=0.076). Median total LOS was significantly longer in the NOM group (34.5h (NOM) vs 17.5 (OM), p=0.01). Median cost of appendectomy was $1416.14 (range $781.24-$2729.97). 9/26 (35%) NOM patients underwent appendectomy for recurrent appendicitis. 4/26 (15%) OM patients were readmitted (postoperative abscess (n=2), Clostridium difficile colitis (n=1), postoperative nausea/vomiting (n=1)). Median initial hospital admission costs were significantly higher in the OM group ($3502.70 (OM) vs $1870.37 (NOM), p=0.004)). However, median total hospital costs were similar for both groups ($3708.68 (OM) vs $2698.99 (NOM), p=0.065)). CONCLUSION: Although initial costs were significantly less in children with acute appendicitis managed nonoperatively, total costs were similar for both groups. The high failure rate of nonoperative management in this series contributed to the total increased cost in the NOM group. LEVEL OF EVIDENCE: 3b.