Nighttime Intensivist Staffing, Mortality, and Limits on Life Support: A Retrospective Cohort Study.

Chest

PubMedID: 25321489

Kerlin MP, Harhay MO, Kahn JM, Halpern SD. Nighttime Intensivist Staffing, Mortality, and Limits on Life Support: A Retrospective Cohort Study. Chest. 2015;147(4):951-8.
Background
Evidence regarding nighttime physician staffing of intensive care units (ICUs) is suboptimal. We aimed to determine how nighttime physician staffing models influence patient outcomes.

Methods
We performed a multicenter retrospective cohort study in a multicenter registry of US ICUs. The exposure variable was the ICU's nighttime physician staffing model. The primary outcome was hospital mortality. Secondary outcomes included new limitations on life support, ICU length-of-stay, hospital length-of-stay, and duration of mechanical ventilation. Daytime physician staffing was studied as a potential effect modifier.

Results
The study included 270,742 patients in 143 ICUs. Compared to nighttime staffing with an attending intensivist, nighttime staffing without an attending intensivist was not associated with hospital mortality (OR 1.03; 95% CI 0.92, 1.15; p=0.65). This relationship was not modified by daytime physician staffing (interaction p=0.19). When nighttime staffing was subcategorized, neither attending non-intensivist nor physician trainee staffing was associated with hospital mortality, compared to attending intensivist staffing. However, nighttime staffing without any physician was associated with reduced odds of hospital mortality (OR 0.79; 95% CI 0.68, 0.91; p=0.002) and new limitations on life support (OR 0.83; 95% CI 0.75, 0.93; p=0.001). Nighttime staffing was not associated with ICU or hospital length-of-stay. Nighttime staffing with an attending non-intensivist was associated with a slightly longer duration of mechanical ventilation (HR 1.05; 95% CI 1.02, 1.09; p<0.001).

Conclusions
We found little evidence that nighttime physician staffing models impact patient outcomes. ICUs without physicians at night may exhibit reduced hospital mortality, possibly attributable to differences in end-of-life care practices.