A review of studies comparing 24/7 in-house intensivist physician coverage with less-intensive models (with no intensivist in the ICU overnight) found no clear or consistent benefits associated with in-house intensivist coverage.

Authors informally reviewed about 50 previous studies and meta-analyses. They concluded that in-house intensivists overnight might reduce ICU length of stay by a few hours, on average.

In multicenter studies, no significant differences in mortality could be found between ICUs with and without overnight intensivists, as long as daytime intensivists are present. One single-center study did show reductions in mortality and length of stay with introduction of a nighttime intensivist in a non-cardiac ICU. Another large database study found that the presence of a nocturnal intensivist could reduce the increased mortality associated with admission on a weekend.

Studies are generally limited by their before-and-after design, lacking adequate controls and subject to the observer/observed (Hawthorne) effect. Even if there were a consistent finding for in-house overnight intensivist coverage, it would be dubious to generalize widely across diverse health systems.

Due to the limited supply of intensivists, who overwhelmingly reside in cities, the "debate" over whether 24-7 intensivist coverage should be standard is largely academic. Round-the-clock intensivist coverage is predominantly a phenomenon of urban, physician-dense population centers; outside cities, most of the U.S. has trouble even staffing their ICUs with intensivists during the day.

Source: Current Opinion in Anesthesiology