Repositioning for pressure injury prevention in adults (Review)

Background
A pressure injury (PI), also referred to as a 'pressure ulcer', or 'bedsore', is an area of localised tissue damage caused by unrelieved pressure, friction, or shearing on any part of the body. Immobility is a major risk factor and manual repositioning a common prevention strategy. This is an update of a review first published in 2014.

Objectives
To assess the clinical and cost effectiveness of repositioning regimens(i.e. repositioning schedules and patient positions) on the prevention of PI in adults regardless of risk in any setting.

Search methods
We searched the Cochrane Wounds Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Ovid Embase, and EBSCO CINAHL Plus on 12 February 2019. We also searched clinical trials registries for ongoing and unpublished studies, and scanned the reference lists of included studies as well as reviews, meta‐analyses, and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication, or study setting.

Selection criteria
Randomised controlled trials (RCTs), including cluster‐randomised trials (c‐RCTs), published or unpublished, that assessed the effects of any repositioning schedule or different patient positions and measured PI incidence in adults in any setting.

Data collection and analysis
Three review authors independently performed study selection, 'Risk of bias' assessment, and data extraction. We assessed the certainty of the evidence using GRADE.

Main results
We identified five additional trials and one economic substudy in this update, resulting in the inclusion of a total of eight trials involving 3941 participants from acute and long‐term care settings and two economic substudies in the review. Six studies reported the proportion of participants developing PI of any stage. Two of the eight trials reported within‐trial cost evaluations. Follow‐up periods were short (24 hours to 21 days). All studies were at high risk of bias. Funding sources were reported in five trials.

Primary outcomes: proportion of new PI of any stage

Repositioning frequencies: three trials compared different repositioning frequencies

We pooled data from three trials (1074 participants) comparing 2‐hourly with 4‐hourly repositioning frequencies (fixed‐effect; I² = 45%; pooled risk ratio (RR) 1.06, 95% confidence interval (CI) 0.80 to 1.41). It is uncertain whether 2‐hourly repositioning compared with 4‐hourly repositioning used in conjunction with any support surface increases or decreases the incidence of PI. The certainty of the evidence is very low due to high risk of bias, downgraded twice for risk of bias, and once for imprecision.

One of these trials had three arms (967 participants) comparing 2‐hourly, 3‐hourly, and 4‐hourly repositioning regimens on high‐density mattresses; data for one comparison was included in the pooled analysis. Another comparison was based on 2‐hourly versus 3‐hourly repositioning. The RR for PI incidence was 4.06 (95% CI 0.87 to 18.98). The third study comparison was based on 3‐hourly versus 4‐hourly repositioning (RR 0.20, 95% CI 0.04 to 0.92). The certainty of the evidence is low due to risk of bias and imprecision.
In one c‐RCT, 262 participants in 32 ward clusters were randomised between 2‐hourly and 3‐hourly repositioning on standard mattresses and 4‐hourly and 6‐hourly repositioning on viscoelastic mattresses. The RR for PI with 2‐hourly repositioning compared with 3‐hourly repositioning on standard mattress is imprecise (RR 0.90, 95% CI 0.69 to 1.16; very low‐certainty evidence). The CI for PI include both a large reduction and no difference for the comparison of 4‐hourly and 6‐hourly repositioning on viscoelastic foam (RR 0.73, 95% CI 0.53 to 1.02). The certainty of the evidence is very low, downgraded twice due to high risk of bias, and once for imprecision.

Positioning regimens: four trials compared different tilt positions

We pooled data from two trials (252 participants) that compared a 30° tilt with a 90° tilt (random‐effects; I² = 69%). There was no clear difference in the incidence of stage 1 or 2 PI. The effect of tilt is uncertain because the certainty of evidence is very low (pooled RR 0.62, 95% CI 0.10 to 3.97), downgraded due to serious design limitations and very serious imprecision.

One trial involving 120 participants compared 30° tilt and 45° tilt with 'usual care' and reported no occurrence of PI events (low certainty evidence). Another trial involving 116 ICU patients compared prone with the usual supine positioning for PI. Reporting was incomplete and this is low certainty evidence.

Secondary outcomes

No studies reported health‐related quality of life utility scores, procedural pain, or patient satisfaction.

Cost analysis

Two included trials also performed economic analyses.

A cost‐minimisation analysis compared the costs of 3‐hourly and 4‐hourly repositioning with 2‐hourly repositioning schedule amongst nursing home residents. The cost of repositioning was estimated at CAD 11.05 and CAD 16.74 less per resident per day for the 3‐hourly or 4‐hourly regimen, respectively, compared with the 2‐hourly regimen. The estimates of economic benefit were driven mostly by the value of freed nursing time. The analysis assumed that 2‐, 3‐, or 4‐hourly repositioning is associated with a similar incidence of PI, as no difference in incidence was observed.

A second study compared the nursing time cost of 3‐hourly repositioning using a 30° tilt with standard care (6‐hourly repositioning with a 90° lateral rotation) amongst nursing home residents. The intervention was reported to be cost‐saving compared with standard care (nursing time cost per patient EUR 206.60 versus EUR 253.10, incremental difference EUR −46.50, 95% CI EUR −1.25 to EUR −74.60).

Authors' conclusions
Despite the addition of five trials, the results of this update are consistent with our earlier review, with the evidence judged to be of low or very low certainty. There remains a lack of robust evaluations of repositioning frequency and positioning for PI prevention and uncertainty about their effectiveness. Since all comparisons were underpowered, there is a high level of uncertainty in the evidence base.

Given the limited data from economic evaluations, it remains unclear whether repositioning every three hours using the 30° tilt versus "usual care" (90° tilt) or repositioning 3‐to‐4‐hourly versus 2‐hourly is less costly relative to nursing time.