INTRODUCTION: Previous reports have demonstrated that prior cardiac surgery is independently associated with in-hospital mortality after infant tracheostomy. We aimed to determine whether these infants would continue to be at increased risk for death following hospital discharge. METHODS: A retrospective review was performed on subjects < 2 y of age who recovered from tracheostomy in the pediatric ICU at our institution between January 2007 and December 2011, with follow-up to December 2013. Survival to 1 y following tracheostomy was the primary outcome variable for the study. Multivariate Cox regression analysis was then performed to determine independent risk factors for death after infant tracheostomy. RESULTS: Forty-two subjects met inclusion criteria, 18 of whom had undergone prior cardiac surgery. Twenty-six subjects (62%) were alive at 1 y post-tracheostomy. Age at tracheostomy, concomitant genetic abnormalities or prematurity, and ventilator dependence at discharge were not statistically different between survivors and those who died. Subjects who died, however, were more likely to have had cardiac surgery prior to tracheostomy (11 [69%] vs 7 [27%], P ‫؍‬ .008) and had longer hospital stay (median 3.4 months [interquartile range: 2.6 -4.6] vs 2.2 months [interquartile range: 1.1-3.5], P ‫؍‬ .045). Multivariate Cox regression analysis revealed only prior cardiac surgery to be independently associated with decreased survival after tracheostomy (hazard ratio 4.7, 95% CI 1.3-16.4, P ‫؍‬ .02). CONCLUSIONS: Prior cardiac surgery is independently associated with decreased survival within 1 y following tracheostomy. Clinicians and families of infants with prior cardiac surgery in whom tracheostomy after cardiac surgery is deemed necessary should consider this risk when planning long-term care.

BACKGROUND: Venovenous extracorporeal membrane oxygenation (VV-ECMO) is used when mechanical ventilation can no longer support oxygenation or ventilation, or if the risk of ventilator-induced lung injury is considered excessive. The optimum mechanical ventilation strategy once on ECMO is unknown. We sought to describe the practice of mechanical ventilation in children on VV-ECMO and to determine whether mechanical ventilation practices are associated with clinical outcomes. METHODS: We conducted a multicenter retrospective cohort study in 10 pediatric academic centers in the United States. Children age 14 d through 18 y on VV-ECMO from 2011 to 2016 were included. Exclusion criteria were preexisting chronic respiratory failure, primary diagnosis of asthma, cyanotic heart disease, or ECMO as a bridge to lung transplant. RESULTS: Conventional mechanical ventilation was used in about 75% of children on VV-ECMO; the remaining subjects were managed with a variety of approaches. With the exception of PEEP, there was large variation in ventilator settings. Ventilator mode and pressure settings were not associated with survival. Mean ventilator F IO 2 on days 1-3 was higher in nonsurvivors than in survivors (0.5 vs 0.4, P 5 .009). In univariate analysis, other risk factors for mortality were female gender, higher Pediatric Risk Estimate Score for Children Using Extracorporeal Respiratory Support (Ped-RESCUERS), diagnosis of cancer or stem cell transplant, and number of days intubated prior to initiation of ECMO (all P < .05). In multivariate analysis, ventilator F IO 2 was significantly associated with mortality (odds ratio 1.38 for each 0.1 increase in F IO 2 , 95% CI 1.09-1.75). Mortality was higher in subjects on high ventilator F IO 2 (6 0.5) compared to low ventilator F IO 2 (> 0.5) (46% vs 22%, P 5 .001). CONCLUSIONS: Ventilator mode and some settings vary in practice. The only ventilator setting associated with mortality was F IO 2 , even after adjustment for disease severity. Ventilator F IO 2 is a modifiable setting that may contribute to mortality in children on VV-ECMO.

Thiamine deficiency is common in children with diabetic ketoacidosis, and this deficiency may be worsened by treatment. When metabolic acidosis persists despite appropriate treatment of diabetic ketoacidosis, other factors such as thiamine deficiency should be considered.