In a national survey of academic medical ICU directors, we found wide variation in the stated number, types and clinical area of protocols available for the care of critically ill adults. Furthermore, in those protocols that are available, variation exists in their content and structure, even for protocols supported by well-developed medical evidence. Specifically, the providers that start and drive the protocols vary widely, both within and among the different content areas.
Our results have important implications for clinical care for critically ill patients. Despite the large body of literature suggesting that protocols for liberation from mechanical ventilation and sedation of mechanically ventilated patients are associated with improved patient care1–3
, many teaching programs do not yet make them available for daily practice. The barriers to clinical protocol adoption may be similar to those to adopting evidence-based guidelines in general and can be categorized into barriers of knowledge, attitudes, or behavior.21, 22
In this case we expect that knowledge barriers are rarely a factor, as it is unlikely that ICU directors in teaching hospitals are unaware of the clinical evidence underpinning protocol use in the ICU. In contrast, barriers of attitude and behavior are more likely contributors to the variation. The attitudinal barriers may include skepticism about specific results of research studies or more generally about the usefulness of clinical protocols as a tool to incorporate those results into practice. Indeed, that clinical protocols are broadly effective is passionately debated. ICU directors may also be concerned about the impact of protocols on education, and feel that the potential clinical benefits do not outweigh the potential negative effects on trainee education. There is limited information on this important question, but what is available suggests that protocols do not affect trainee knowledge.11
Behavioral barriers include structural barriers to protocol adoption in academic hospitals. Protocols are time consuming to develop and frequently require multiple levels of administrative review and oversight. There are also financial costs associated with training clinicians to implement and measure the efficacy of new protocols. In the absence of robust data about the clinical benefit of protocols in all practice settings, institutions may deem that such efforts are not worthwhile. However, these barriers to guideline adoption may not explain all the apparent variation in clinical protocol availability. Were this the case, we would expect higher concordance among individual protocols. An ICU that overcomes these barriers in one clinical area should be more likely to overcome them in other clinical areas. That there was at best fair concordance between individual protocols suggests that other forces are in play. More study of clinical protocols is needed to better understand how their development and implementation differs from adoption of clinical guidelines.
In addition to general variation in protocol availability between hospitals, we observed differences in availability between protocols. Surprisingly, protocols were less common in the clinical situations in which the standardized practice has the greatest impact on mortality, such as early goal-directed therapy for severe sepsis13
and lung-protective ventilation for acute lung injury.14
This pattern may reflect that clinicians are unwilling to create protocols for care in settings of diagnostic uncertainty—as sepsis and acute lung injury are both clinical syndromes that are difficult to reliably identify.23
Conversely, liberation from mechanical ventilation and sedation management of mechanically ventilated patients manage elements of care for a patient category without diagnostic uncertainty. We found that these more common protocols are also more likely to be started and driven primarily by non-physicians. Perhaps this finding reflects a greater comfort with the use of clinical protocols to appropriately turn over management responsibilities to non-physicians when less clinical uncertainty exists, or physicians’ unwillingness to develop protocols to standardize their own behaviors compared to the behaviors of other providers.
Our results also have important implications for medical education. Protocols in teaching ICUs may deprive trainees of important educational experiences. Indeed, respondents indicated that trainees are infrequently the primary drivers of clinical protocols. This may result in multiple degrees of separation between trainees and clinical decision-making. Conversely, in teaching ICUs without clinical protocols, trainees may not learn the evidence behind protocol use in the ICU. Furthermore, they are less likely to learn the skills necessary to develop, implement, and test the efficacy of protocol-driven care, although even with clinical protocols, trainees may have limited exposure to these processes, as they are often time-intensive, behind-the-scenes, and incompletely performed. Still unanswered is whether the presence of evidence-based protocols facilitates education about the best management practices by providing a consistent structure or impedes education by removing opportunities to engage in critical thinking. Further exploration of this question is imperative as protocol use and training practices continue to evolve.
The only association we found between hospital or ICU characteristics and protocol availability was between high teaching intensity and having a protocol for liberation from mechanical ventilation. Due to the small number of training programs, the study was underpowered to detect all but the largest differences in protocol availability between different hospital types. As a result, it is difficult to draw conclusions about the associations between hospital characteristics and protocol availability. Further studies of broader populations of ICUs could elucidate these relationships further.
Our study has several limitations. First, as with all survey research, some questions were subject to some interpretation by respondents. We attempted to provide clarification whenever possible, by describing clinical scenarios, for example, but we recognize this as a potential limitation. Second, we restricted our study population to adult medical ICUs of training programs because we aimed to study how clinical protocols may be useful in such settings and how they may affect trainee education. Although there was variation in ICU size, region, and teaching intensity, our findings may not extend to non-academic or non-medical ICUs. Third, although there was variation in the presence of specific protocols, very few ICUs had none or only one protocol, limiting our ability to study characteristics of programs that prefer not to use any protocols. Although it is possible that this represents a response bias (i.e., that ICUs without protocols did not complete the questionnaire), we found no significant differences in hospital characteristics among respondents and non-respondents. Fourth, the survey can only evaluate stated practice and cannot evaluate adherence to or use of the protocols. Our data likely overestimate the actual availability and use of protocols.24
The mere existence of a protocol may not influence practice or education in any way if the protocol is not actually employed. In fact, in one study of adherence to a lung-protective ventilation protocol, less than 40% of appropriate patients received low tidal volume ventilation within two days of diagnosis of acute lung injury.25
However, we did not believe that any information on the subject of adherence or use would be reliable in questionnaire format.16, 17
In addition, we only obtained limited details on the content of the protocols, in order to keep the questionnaire short so as to obtain a high response rate. Further study of the content of clinical protocols will be an important future direction to better understand their potential impact. Finally, although our study describes whether clinicians have access to protocols in teaching ICUs, it does not directly address the impact of protocols on the quality of medical education. This issue is another key area for future research.