Pressures to Bony Prominences in Lateral Turned Position - Comparison of Pressure Reduction Achieved by Support Device Used


Clinical Problem
Pressure Injury is a significant health issue worldwide. Although incidence, prevalence, cost, morbidity and mortality rates vary greatly depending on the reporting source, the gravity of the problem is indisputable. We all have a vested interest in resolving the problem. Of all the interventions the health care team can and should do to help reduce pressure injury incidence and prevalence, no practice is more important than removing pressure.

About 50% of all pressure injuries occur over the trunk region of the body, especially the sacral/coccyx area. It is particularly difficult to remove pressure to this area on a bedbound person, but our best chance of doing so it to turn an at-risk person 30 degrees laterally. “Turning” is the theoretically optimal method to remove pressure from the sacral/coccyx area because this position hypothetically “tilts” and lifts a person’s sacrum/coccyx are just far enough to remove pressure, but not too far so as to position the person onto the opposite side greater trochanter.

It makes perfect sense that turning to remove pressure will reduce pressure injuries. Turning is so clearly the right thing to do that the intervention is considered a standard of care worldwide, ubiquities to all settings where pressure injuries can and do occur.

But if turning works so well, why are pressure injuries in the Sacral/coccyx area still commonplace? We continue to see widespread incidence, especially in community acquired incidence. But pressure injuries are far too common even in the most advanced health care environments, where medical care, nurse staffing, adherence to preventative protocols and expertise should be more than adequate to prevent them.

Past Management
With the understanding that turning is key to preventing injury, research has focused on the study of turning frequency to find answers. The rational being that there is a theoretical threshold of time between turns that is just often enough to prevent or heal pressure injury. The current deeply ingrained paradigm in health care is that an at-risk person should be turned every two hours. There are many well designed studies that put the q2h paradigm to the test. Although virtually all have found measurable reductions in pressure injury rates with frequent turning, there is still great variability of results for exact frequency of time that will yield the lowest rates. A straight answer to the turn frequency question remains elusive.

A significant limitation of the past turning studies which may account for the variance in results, is the lack of standardization of turned position itself, and the lack data of actual pressures exerted onto the sacral area during the measurement period. In practice, nurses are accustomed to frequent “failures” of the turned position. It is difficult, if not impossible, for the nurse to know whether the turned position has achieved adequate pressure reduction, and it is common knowledge that pillows “bottom out” and wedges “slip out.” It is then easy to observe when the patient is no longer in the turned position, which can happen in as little as 15 minutes. The most common cause of support “failure” is patient shifting or complaints, where the position or the support or both are intolerable for the patient and adjustments have to be made. All too often that adjustment is to return the patient to a supine position.

Without first knowing if the patient's turned position has achieved best possible pressure reduction and for how long that depressurized state is maintained, we will not be able to determine an optimal turn frequency for pressure injury prevention.

Current Approach
The hypothesis of this case study is that direct pressures in the turned position vary greatly depending on the support device used to support the position. We tested four regularly used devices to support the turned position. 1) The common pillow; 2) a long, straight-edged triangle wedge cushion cut to 30/60/90-degree angles; 3) a crescent shaped wedge cut to an isosceles triangle 20/20/80-degree angles; and 4) a two-piece design of two small straight edges triangle wedge cushions cut to 30/60/90 degree angles. Our subject is a 53 year-old quadriplegic male. Using a handheld pressure monitor, we measured direct pressures on the sacrum, greater trochanters, buttocks, and scapulas while supported by each support device. We also measured approximate angle of turn from the sternum and center pelvis achieved by each support device. We asked the subject to report relative comfort of each device as benchmark gauge for sustainability of support over an extended period of time.

The level of pressure reduction in lateral turned position varies dramatically depending on the device used and the angle of turn accomplished by the devices. The highest pressure measured against the sacrum in the turned position was 24mmHg from the large triangle wedge (likely related to the fact that this wedge made direct contact to the sacrum and pressure monitor). The lowest pressure measured was 3mmHg, from the crescent shaped wedge. Very near lowest measure was 5mmHg from the two-piece wedge. Pillows scored lower than the wedge in pressure (16mmHg), and best in comfort (3 on a scale of 0-10), but they supported only a 15 degree angle as measured from the pelvis, leaving the subject closer to a “bottom out” angle. Best overall pressure reduction was achieved by the crescent shaped wedge as measured by calculating the average of all pressures.

There was a significant variance of depressurization to the other bony prominences measured, and angles of turn between support devices by each support device. It is significant to note was that both triangle 30/60/90 wedge configurations supported the subject at a turned angle of >45 degrees. This angle caused excessive pressure to the opposite greater trochanter, reaching 70mmHg with the two-piece wedge system. The subject complained of excessive discomfort with the two-piece system as well.

Implications and future studies
Future studies to measure the capacity of each support device to maintain adequate support and depressurization over time is warranted. It is likely that pressures and turned angle will change greatly over a short period of time. Important considerations include stability of the support device and the patient, level of immersion onto the mattress surface, distribution of pressures, angle of turn, head of bed angle and sliding. Exploration into how physical movement, physiological condition and patient comfort may affect position and pressure reduction would be highly contributive to improving the effectiveness of turning.


1. Bergstrom N., Horn S.D., Rapp M.P., Stern A., Barrett R., Watkiss M. Turning for Ulcer Reduction (TURN): A multisite randomized clinical trial in nursing homes. J Am Geriatr Soc. 2013 Oct: 61(10) 1705-13
2. Borgueta, E.M. Musafar, A. Elk, K.R, Fay, M. S.T.O.P (Synchronized Turning of Patients) Reduction of Hospital Acquired Pressure Injury in the Intensive Care Unit. CCRN Annual Conference 2018 Poster Presentation.
3. Brindle C.T., Creehan S., Black, J. Zimmerman D. The VCU Pressure Ulcer Summit: Collaboration to Operationalize Hospital-Acquired Pressure Ulcer Prevention Best Practice Recommendations. Journal of Wound, Ostomy & Continence Nursing: July/August 2015; 42(4) 331-37
4. Bush T.R., Leitkam S., Aurino M., Cooper A., Basson M.D. A Comparison of Pressure Mapping Between Two Pressure-Reducing Methods for the Sacral Region. Journal of Wound, Ostomy and Continence Nursing 2015;42(4):338-345
5. Buss I., Halfens R., Abu-Saad H. The Most Effective Time Interval For Repositioning Subjects At Risk of Pressure Sore Development. Rehabilitation Nursing 2002;27(2):59-66
6. Defloor T., De Bacquer D., Grypdonck M.H. The Effect of Various Combinations of Turning and Pressure Reducing Devices on the Incidence of Pressure Ulcers. Int J Nurs Study; 2005;42(1):37-46
7. Gillespie B.M, Chaboyer W.P, McInnes E., Kent B., Whitty J.A., Thalib L. Repositioning for pressure ulcer prevention in adults. Cochrane Database of Systematic Reviews 2014, Issue 4. Art. No.: CD009958
8. Krapfl L.A., Gray M. Does Regular Repositioning Prevent Pressure Ulcers?. Journal of Wound, Ostomy and Continence Nursing 2008;35(6):571-7
9. Kennerly, S, Yap, T The Role of Manual Patient Turning in Prevention Hospital Acquired Conditions. A white paper for Leaf Healthcare, 2016
10. Lavine, J. New Research Challenges “Q2H” Turning Standard for Pressure Injury Prevention. 2013,
11. Meehan M. National Pressure Ulcer Prevalence Survey. Adv Wound Care 1994; 7:27-37
12. National Pressure Ulcer Advisory Panel & European Pressure Ulcer Advisory Panel. Prevention and Treatment of Pressure Ulcers, Clinical Practice Guidelines. NPUAP & EPIAP. Washington, 2009
13. Nixon J., Nelson E.A., Cranny G., Iglesias C.P., Hawkins K., Cullum N.A. et al. Pressure Relieving Support Surfaces: A Randomized Evaluation. Health Technology Assessment 2006; 10(22): 1-180
14. Peterson M.J., Schwab W., van Oosrom J.H., Gravenstein N., Caruso L.J. Effects of Turning On Skin-Bed Interface Pressures in Healthy Adults. J Adv Nurs. 2010 Jul;66(7):1556-64
15. Pickham, D., Berte, N. Pihulic, M. Valdez, A. Mayer, B. Desai, M. Effect of a Wearable Patient Sensor On Care Delivery For Preventing Pressure Injuries in Acutely Ill adults: A pragmatic randomized clinical trial (LS-HAPI study). Intl Journal of Nursing Studies 80 (2018) 12-19.
16. Powers J. Two Methods for Turning and Positioning and the Effect on Pressure Ulcer Development. J Wound Ostomy Continence Nurs. 2016;43(1):46-5
17. Reddy M., Gill S., Rochon P. Preventing Pressure Ulcers: A Systematic Review. JAMA 2006; 296(8): 974-84
18. Shardell, M. et al. Frequent manual repositioning and incidence of pressure ulcers among bedbound elderly hip fracture patients Wound Repair Regen. 2011 January ; 19(1): 10–18.
19. Thomas, D. R. Prevention and Treatment of Pressure Ulcers, J Am Med Dire Assoc 2006; 7: 46-59
20. Vanderwee K., Grypdonck M., Defloor T. Effectiveness of an Alternating Pressure Air Mattress for the Prevention of Pressure Ulcers. Age and Aging 2005; 34: 261-7
21. Wong V., Skin Blood Flow Response To 2-hour Repositioning in Long-Term Care Residents. A pilot study. J Wound Ostomy Continence Nurs. 2011;38(5):529-537
22. Yap, T.L, Cox, J.Turning and Repositioning Science and Implementation. 2018 National Pressure Ulcer Advisory Panel Conference Lecture Presentation.
23. Lavine, J. New Research Challenges “Q2H” Turning Standard for Pressure Injury Prevention. 2013,

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