Impact of Nonphysician Staffing on Outcomes in a Medical ICU


      As the number of ICU beds and demand for intensivists increase, alternative solutions are needed to provide coverage for critically ill patients. The impact of different staffing models on the outcomes of patients in the medical ICU (MICU) remains unknown. In our study, we compare outcomes of nonphysician provider-based teams to those of medical house staff-based teams in the MICU.


      We conducted a retrospective review of 590 daytime (7:00 am-7:00 pm) admissions to two MICUs at one hospital. In one MICU staffed by nurse practitioners and physician assistants (MICU-NP/PA) there were nonphysicians (nurse practitioners and physicians assistants) during the day (7:00 am-7:00 pm) with attending physician coverage overnight. In the other MICU, there were medicine residents (MICU-RES) (24 h/d). The outcomes investigated were hospital mortality, length of stay (LOS) (ICU, hospital), and posthospital discharge destination.


      Three hundred two patients were admitted to the MICU-NP/PA and 288 to the MICU-RES. Mortality probability model III (MPM0-III) predicted mortality was similar (P = .14). There was no significant difference in hospital mortality (32.1% for MICU-NP/PA vs 32.3% for MICU-RES, P = .96), MICU LOS (4.22 ± 2.51 days for MICU-NP/PA vs 4.44 ± 3.10 days for MICU-RES, P = .59), or hospital LOS (14.01 ± 2.92 days for MICU-NP/PA vs 13.74 ± 2.94 days for MICU-RES, P = .86). Discharge to a skilled care facility (vs home) was similar (37.1% for MICU-NP/PA vs 32.5% for MICU-RES, P = .34). After multivariate adjustment, MICU staffing type was not associated with hospital mortality (P = .26), MICU LOS (P = .29), hospital LOS (P = .19), or posthospital discharge destination (P = .90).


      Staffing models including daytime use of nonphysician providers appear to be a safe and effective alternative to the traditional house staff-based team in a high-acuity, adult ICU.
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