As all Keystone ICU participating sites responded to the questionnaire, we believe these results to be representative of critical care practice in the state of Michigan at the present time. Michigan ICU staffing structures are variable. Only a minority (25%) of Michigan Keystone ICU sites operated in an environment where intensivists are the only attending physicians of record. Although intensivists rounded in 60% of sites not utilizing a closed model, seventy five percent of sites had non-intensivist attending physicians, with primary care physicians and hospitalists commonly providing ICU services. The utilization of hospitalists to provide critical care services was found in the absence of intensivists, regardless of hospital or ICU size.
Closed ICUs were seen in larger hospitals and in larger ICUs. This finding is similar to data obtained on a national level (9
). A high-intensity model of care was also uncommon, although decision making was at least shared between intensivists and non-intensivists at two third of sites. These findings are in keeping with the observation that intensivist directed care advocated by the Leapfrog Group has not been widely implemented (18
) including in Michigan, a regional roll-out leader for the Leapfrog Group.
Fewer ICUs reported utilizing a non-intensivist model than was reported in the survey by Angus et al., where approximately half of ICUs delivered care in this manner (9
). This survey was performed in 1997, prior to the launch of the Leapfrog Group effort, and may have reflected a relative over representation of smaller, general intensive care units. Our study is the first statewide analysis of critical care practices in the post Leapfrog Group era. Our finding that an array of approaches to critical care delivery existed in Michigan, even when intensivists rounded on patients, is similar to that found among Leapfrog compliant hospitals sampled from several regions of the United States (19
Other than intensivists, surgeons, primary care, and hospitalist physicians provided care in Michigan ICU's. The hospitalist movement is relatively new (20
). However in our survey 37.5% of sites had hospitalists serving as attending physicians. Although the closed ICU model was more prevalent in larger ICUs and hospitals, the use of a hospitalist model to staff ICUs was not related to hospital size, but was instead a function of whether or not intensivists were present in a given setting. In lieu of a projected shortage of intensivists, we believe this confirms the crucial role that hospitalists will play in the provision of critical care services in the future.
The attributes of intensivist care that lead to improved outcomes in previous studies (1
) are unknown. To the extent that the involvement of intensivists on an elective rather than mandatory consultative basis may explain the higher mortality found in one recent study (11
), we hypothesize that having a knowledgeable physician present who communicates with clinicians and families and manages at the unit level is an important factor leading to improved outcomes. While hospitalists can have these attibutes, their knowledge of specific critical care therapies and technologies may vary with the extent of their ICU training and experience. Further research should seek to quantify the attributes by which intensivists are associated with improved outcomes and seek ways to foster those attributes among hospitalists who participate in critical care delivery. Central to this will be ensuring that training programs ensure competency in critical care therapies and technologies among hospitalists and other non-ICU physicians.
We recognize several limitations in this study. First, the validity of the survey may introduce misclassification of ICU staffing. However, the survey instrument was informed by previously validated instruments and experts in ICU physician staffing and hospitalist care. Second, we did not link variation in staffing to outcomes. While such analysis is important, it is beyond the scope of this survey. Third, our study was conducted in one state and the results may not be generalizable across the United States. Nevertheless, Michigan is a large state with a diverse array of hospitals, and as our study sample broadly represented this diversity, we believe our results are likely to be generalizable.
In conclusion, few ICUs in Michigan are closed and many utilize non-intensivist critical care providers such as hospitalists, primary care providers, and physician extenders to deliver clinical care. Our findings have significant implications for future efforts at a national level that involve the training of hospitalists and their acceptance as critical care practitioners. We suggest future research involving intensive care delivery focus on the feasibility of training sufficient hospitalists to satisfy a growing need for critical care which cannot be filled by intensivists along with strategic planning to insure the model of care provided is commensurate with the complexity of illness. Although this approach appears to be occurring in Michigan on an ad hoc basis, we believe coordination between larger, intensivist run ICUs and smaller, non-intensivist run ICUs should be formalized in order to optimize the delivery of intensive care (25