REVIEW QUESTION

What are the effects of lateral positioning on morbidity, mortality, and adverse events in critically ill adult patients?

TYPE OF REVIEW

A systematic review of 24 randomized and quasi-randomized controlled trials; only two were included in a meta-analysis.

RELEVANCE FOR NURSING

Routine lateral positioning has been proposed as one way to minimize or prevent complications from bed rest in critically ill patients while still maintaining adequate oxygen delivery and tissue oxygenation. The benefits of lateral positioning include increased patient comfort; prevention of pressure injury; and reduced deep vein thrombosis, pulmonary emboli, atelectasis, and pneumonia.

Routine lateral positioning may not be appropriate for all patients, however, particularly those susceptible to cardiopulmonary and circulatory dysfunction; and respiratory and hemodynamic instability are common reasons for patient intolerance to lateral positioning. Because critically ill patients are often kept supine, the effects of lateral positioning in these patients are largely unknown.

CHARACTERISTICS OF THE EVIDENCE

The objective of this review was to examine the effects of lateral positioning compared with other body positions on morbidity, mortality, and clinical adverse events in critically ill adult patients. Clinical adverse events included hypoxemia, hypotension, low oxygen delivery, and global indicators of impaired tissue oxygenation.

The review included randomized and quasi-randomized clinical trials of adult patients (16 years and older) who were classified or described as critically ill. The review considered interventions that included the use of lateral positioning (as a single or repeated therapy, or right- or left-side positioning) maintained for a minimum of 10 minutes or longer. Comparative interventions included body positions such as opposite lateral side, supine, semirecumbent, high Fowler's position, prone Trendelenburg, reverse Trendelenburg, or a sequence of positions. Studies were excluded if they were conducted in the operating room or investigated children, pregnant women, or patients with spinal cord injury. A total of 24 studies were included in the review.

No studies reported mortality as an outcome and only two reported morbidity. The remaining studies reported clinical adverse events, but only two of these were able to be included in a meta-analysis. These studies examined partial pressure of arterial oxygen (PaO₂) as a measure for detecting hypoxemia in patients with unilateral lung disease and compared lateral positions where the bad lung was down (the more diseased lung was lower) with positions where the good lung was down. The meta-analysis showed that PaO₂ was significantly lower when the bad lung was down.

BEST PRACTICE RECOMMENDATIONS

No clear evidence of the effectiveness of lateral positioning in critically ill adult patients was found. Clinical decisions about whether to place the patient in the lateral position, as well as the duration and frequency of this position, should be made on a case-by-case basis with reference to local guidelines and acceptable parameters. Because of the methodological shortcomings and unclear risks of bias in these studies, results should be viewed with caution.

RESEARCH RECOMMENDATIONS

Further research is needed and should focus on consistent approaches in the reporting of methods, participant characteristics, and outcomes. Future research should also address whether the routine practice of lateral positioning benefits all, some, or only a few critically ill patients, and whether there is any body position that is best avoided in these patients.

REFERENCE