Objectives: Little is known about the relationship between freestanding children's hospitals and outcomes in children with critical illness. The purpose of this study was to evaluate the association of freestanding children's hospitals with outcomes in children with critical illness.
Design: Propensity score matching was performed to adjust for potential confounding variables between patients cared for in freestanding or nonfreestanding children's hospitals. We tested the sensitivity of our findings by repeating the primary analyses using inverse probability of treatment weighting method and regression adjustment using the propensity score.
Setting: Retrospective study from an existing national database, Virtual PICU Systems (LLC) database.
Patients: Patients less than 18 years old admitted to one of the participating PICUs in the Virtual PICU Systems, LLC database were included (2009-2014).
Measurements and main results: A total of 538,967 patients from 140 centers were included. Of these, 323,319 patients were treated in 60 freestanding hospitals. In contrast, 215,648 patients were cared for in 80 nonfreestanding hospitals. By propensity matching, 134,656 patients were matched 1:1 in the two groups (67,328 in each group). Prior to matching, patients in the freestanding hospitals were younger, had greater comorbidities, had higher severity of illness scores, had higher incidence of cardiac arrest, had higher resource utilization, and had higher proportion of patients undergoing complex procedures such as cardiac surgery. Before matching, the outcomes including mortality were worse among the patients cared for in the freestanding hospitals (freestanding vs nonfreestanding, 2.5% vs 2.3%; p < 0.001). After matching, the majority of the study outcomes were better in freestanding hospitals (freestanding vs nonfreestanding, mortality: 2.1% vs 2.8%, p < 0.001; standardized mortality ratio: 0.77 [0.73-0.82] vs 0.99 [0.87-0.96], p < 0.001; reintubation: 3.4% vs 3.8%, p < 0.001; good neurologic outcome: 97.7% vs 97.1%, p = 0.001).
Conclusions: In this large observational study, we demonstrated that ICU care provided in freestanding children's hospitals is associated with improved risk-adjusted survival chances compared to nonfreestanding children's hospitals. However, the clinical significance of this change in mortality should be interpreted with caution. It is also possible that the hospital structure may be a surrogate of other factors that may bias the results.