Aeration strategy at birth influences the physiological response to surfactant in preterm lambs.

BACKGROUND: The influence of pressure strategies to promote lung aeration at birth on the subsequent physiological response to exogenous surfactant therapy has not been investigated. OBJECTIVES: To compare the effect of sustained inflation (SI) and a dynamic positive end-expiratory pressure (PEEP) manoeuvre at birth on the subsequent physiological response to exogenous surfactant therapy in preterm lambs. METHODS: Steroid-exposed preterm lambs (124-127 days' gestation; n=71) were randomly assigned from birth to either (1) positive-pressure ventilation (PPV) with no recruitment manoeuvre; (2) SI until stable aeration; or (3) 3 min dynamic stepwise PEEP strategy (maximum 14-20 cmH2O; dynamic PEEP (DynPEEP)), followed by PPV for 60 min using a standardised protocol. Surfactant (200 mg/kg poractant alfa) was administered at 10 min. Dynamic compliance, gas exchange and regional ventilation and aeration characteristics (electrical impedance tomography) were measured throughout and compared between groups, and with a historical group (n=38) managed using the same strategies without surfactant. RESULTS: Compliance increased after surfactant only in the DynPEEP group (p<0.0001, repeated measures analysis of variance), being 0.17 (0.10, 0.23) mL/kg/cmH2O higher at 60 min than the SI group. An SI resulted in the least uniform aeration, and unlike the no-recruitment and DynPEEP groups, the distribution of aeration and tidal ventilation did not improve with surfactant. All groups had similar improvements in oxygenation post-surfactant compared with the corresponding groups not treated with surfactant. CONCLUSIONS: A DynPEEP strategy at birth may improve the response to early surfactant therapy, whereas rapid lung inflation with SI creates non-uniform aeration that appears to inhibit surfactant efficacy.

Neonatal oesophageal perforation: The role for non-operative management.

AIM: Isolated oesophageal perforation in neonates is a rare but potentially life-threatening condition. Although management has historically been operative, conservative management (antibiotics, bowel rest, parenteral nutrition) is now more routinely used. The aim of this study was to evaluate the management of this condition in two large neonatal surgical centres. METHODS: A retrospective cohort study was conducted for neonates admitted to The Hospital for Sick Children (Toronto, Canada) or The Royal Children's Hospital (Melbourne, Australia) with a diagnosis of oesophageal perforation, from 2006 to 2016. Patients with oesophageal atresia or tracheo-oesophageal fistula were excluded. Data were collected from chart review regarding demographics, clinical course, management and outcomes. RESULTS: Eleven neonates with oesophageal perforation were identified over a 10-year period at the two centres. Median gestational age at birth was 25.3 weeks (interquartile range 24.2-28.8) and the majority (7/11, 64%) of neonates were extremely low birthweight. Diagnosis was made on day 1 of life for 9 of 11 (81%) neonates and was secondary to nasogastric tube insertion in 10 of 11 (91%) neonates. Only four (36%) neonates had symptomatic complications. All neonates were managed with bowel rest and intravenous antibiotics for a median of 7 days (interquartile range 7-10); two patients required operative intervention. Three neonates (27%) developed chronic lung disease and two (19%) died prior to discharge. CONCLUSIONS: Oesophageal perforation is severe complication secondary to instrumentation of the upper gastrointestinal tract in neonates. Prompt and accurate diagnosis is crucial. Non-operative management is effective for the majority, though morbidity is common.