Backrest position in prevention of pressure ulcers and ventilator-associated pneumonia: conflicting recommendations

Impact of head-of-bed elevation angle on the development of pressure ulcers and pneumonia in patients on mechanical ventilation: a systematic review and meta-analysis

BACKGROUND

Mechanical ventilation is crucial for patient management in intensive care units, but it comes with complications such as pressure ulcers and ventilator-associated pneumonia (VAP). The impact of head-of-bed elevation angles on these complications remains a critical area for investigation.

METHODS

This systematic review and meta-analysis followed PRISMA guidelines and involved searches across PubMed, Embase, Web of Science, and Cochrane Library, conducted on September 19, 2023, with no date or language restrictions. We included randomized controlled trials that compared different head-of-bed elevation angles in adult ICU patients on mechanical ventilation. Data were extracted on study characteristics, quality assessed using the Cochrane risk of bias tool, and statistical analyses performed using chi-square tests for heterogeneity and fixed or random-effects models based on heterogeneity results.

RESULTS

Six studies met inclusion criteria out of an initial 601 articles. These studies showed minimal heterogeneity (I2 = 0.0% for pressure ulcers, p = 0.930; and for VAP, p = 0.797), supporting the use of fixed-effect models. Results indicated that a higher elevation angle (45°) significantly increased the risk of pressure ulcers (OR = 1.95, 95% CI: 1.12-3.37, p < 0.05) and decreased the incidence of VAP compared to a lower angle (30°) (OR = 0.51, 95% CI: 0.31-0.84, p < 0.05).

CONCLUSIONS

While higher head-of-bed elevation can reduce the risk of VAP in mechanically ventilated patients, it may increase the risk of pressure ulcers. Clinical strategies should carefully balance these outcomes to optimize patient care in ICU settings.

REGISTRATION

PROSPERO 2024 CRD42024570232.

Impact of shear stress on sacral pressure injury from table rotation during laparoscopic colorectal surgery performed in the lithotomy position

This study aimed to evaluate the impact of shear stress on surgery-related sacral pressure injury (PI) after laparoscopic colorectal surgery performed in the lithotomy position. We included 37 patients who underwent this procedure between November 2021 and October 2022. The primary outcome was average horizontal shear stress caused by the rotation of the operating table during the operation, and the secondary outcome was interface pressure over time. Sensors were used to measure shear stress and interface pressure in the sacral region. Patients were divided into two groups according to the presence or absence of PI. PI had an incidence of 32.4%, and the primary outcome, average horizontal shear stress, was significantly higher in the PI group than in the no-PI group. The interface pressure increased over time in both groups. At 120 min, the interface pressure was two times higher in the PI group than in the no-PI group (PI group, 221.5 mmHg; no-PI group, 86.0 mmHg; p < 0.01). This study suggested that shear stress resulting from rotation of the operating table in the sacral region by laparoscopic colorectal surgery performed in the lithotomy position is the cause of PI. These results should contribute to the prevention of PI.

Implementation of Pressure Injury Prevention Strategies in Acute Care: Results From the 2018-2019 International Pressure Injury Prevalence Survey

PURPOSE

The purpose of this study was to evaluate the implementation of pressure injury (PI) prevention strategies in adult acute care settings in the United States using the data from the 2018/2019 International Pressure Ulcer Prevalence (IPUP) Survey.

DESIGN

Observational, cohort study with cross-sectional data collection and retrospective data analysis.

SUBJECTS AND SETTING

The sample comprised 296,014 patients hospitalized in 1801 acute care facilities in the United States that participated in the 2018 and/or 2019 IPUP Survey. Slightly less than half (49.4%, n = 146,231) were male, 50% (n = 148,997) were female, 0.6% (n = 17,760) were unknown. Their mean age was 64.29 (SD 17.2) years.

METHODS

Data from the 2018/2019 IPUP database were analyzed to evaluate the implementation of prevention strategies including repositioning, support surface use, head-of-bed (HOB) elevation, heel elevation, moisture management, minimizing linen layers, and nutritional support. Practices were analyzed for differences between patients without pressure injuries, and patients with Stage 1 and 2 hospital-acquired pressure injury (HAPI), and those with severe HAPIs (Stage 3, Stage 4, unstageable, and deep tissue pressure injury). Acute care unit types included critical or intensive care units, medical-surgical inpatient care units, and step-down units.

RESULTS

Compliance rates to PI prevention strategies varied among patients at risk for HAPIs (Braden Scale for Pressure Sore Risk score ≤18). Daily skin assessment was performed for 86% of patients with no HAPIs and 96.8% of patients with severe HAPIs. Pressure redistribution was used in 74.6% of all patients and in over 90% of patients with severe HAPIs; however, compliance to routine repositioning was reported at lower levels between 67% and 84%, respectively. Heel elevation was reported for over 60% of the patients with severe HAPIs while 31.9% did not receive heel elevation, though only 6% were reported as not needing elevation. The majority of patients had HOB greater than the 30° at the time of the data collection; compliance with minimizing linen layers (≤3) was reported in 76% or more. Moisture management strategies were reportedly used in more than 71% of all patients and 89% for patients with severe HAPIs. Nutrition support was used for 55% to 82% of the patients and only documented as contraindicated in fewer than 2% of all groups.

CONCLUSION

Study findings revealed substantial compliance rates to PI prevention strategies. Nevertheless, there is potential for improvement in the implementation of some of the most basic prevention strategies including repositioning, heel elevation, nutritional support, and moisture management.

Comparing the Interface pressure distribution of the full body chest-lumbar cushion made of memory cotton with the traditional chest cushion

BACKGROUND

Pressure injuries are common complications occurred duration hospitalization, whether the interface pressure distribution in full body memory cotton chest-lumbar cushion was superior than traditional chest cushion remains unclear.

PURPOSE

This study aimed to compare the effects that the full body memory cotton chest-lumbar cushion versus traditional chest cushion on interface pressure.

METHODS

A total of 66 healthy individuals were recruited. The volunteers were placed in the left lateral position and left armpit and iliac spine pressure and level of comfort were measured. Group differences were assessed using the paired t-test or Wilcoxon test according to data distribution. Additionally, multivariate regression analysis was applied to determine the potential role of sex, age, and body mass index on left armpit and iliac spine pressure and overall comfort.

RESULTS

Compared with the traditional chest cushion, we noted that the full body chest-lumbar cushion made of memory cotton was associated with less pressure on the left armpit (38.17 ± 10.39 mmHg vs. 67.93 ± 14.67 mmHg, respectively; P < 0.0001) and iliac spine (43.32 ± 13.70 mmHg vs. 50.77 ± 20.94 mmHg, respectively; P = 0.0004). Moreover, we noted that the overall comfort with the memory cotton chest-lumbar cushion was higher than that with the traditional chest cushion (8.48 ± 1.08 vs. 6.36 ± 1.45, respectively; P < 0.0001). Finally, the multivariate regression analyses found iliac spine pressure could affect by sex (P = 0.0377) and body mass index (P = 0.0380).

CONCLUSIONS

The full body chest-lumbar cushion made of memory cotton had beneficial effects on left armpit and iliac spine pressure and on comfort. These findings should be applied to future clinical practice.

Backrest elevation in the semi-lateral position: Case of a sacral pressure ulcer with undermining formation

Backrest elevation for a patient with a sacral-coccygeal pressure ulcer is necessary in certain situations, particularly to enable the patient to take meals. Deep pressure ulcers with undermining formations affect patients and create challenges for caregivers. The procedure of backrest elevation potentially worsens the pre-existing sacral-coccygeal pressure ulcers with undermining formations. Here, we report a Case of the clinical care of a patient using a simple approach for backrest elevation that minimizes additional injury to the existing sacral pressure ulcer covered with granulation tissue. In this case, we performed the backrest elevation in the semi-lateral position. After the backrest elevation, the patient was repositioned to the supine position to take a meal. The supine position was allowed at any time except during backrest elevation. The pressure ulcer of the patient improved rapidly using the combined treatment of our positioning approach and appropriate topical ointments. This practical approach may be effective for some patients as it potentially decreases the effect of shear force. The rationale for this approach can be explained by the mechanism of the undermining formation outlined in our experimental study using a pressure ulcer model mounted to a phantom. Although we used this position for patients with sacral-coccygeal pressure ulcers, this simple approach may also be considered for other patients based on our proposed pathogenesis of undermining formations.

Brief intermittent pressure off-loading on skin microclimate in healthy adults - A descriptive-correlational pilot study

AIM

This study examined microclimate changes to the skin as a result of pressure over a 1 h period. The results were compared to skin parameter results following brief consecutive off-loading of pressure-prone areas.

DESIGN

A descriptive-correlational pilot study was undertaken.

METHOD

A convenience sample of 41 healthy adults aged 18-60 years was recruited. Participants engaged in four 1 h data collection sessions. The sessions were conducted in both semi-recumbent and supine positions. Measures of erythema, melanin, stratum corneum hydration, and skin temperature were taken at pressure-prone areas at baseline and after 1 h in an uninterrupted method (continuous pressure-loading) and every 10 min in an interrupted method (brief off-loading). The Corneometer and Mexameter (Courage + Khazaka Electronics GMbH, 2013) and Exergen DermaTemp DT-1001 RS Infrared Thermographic Scanner (Exergen Corporation, 2008) provided a digital appraisal of skin parameters. Intraclass correlation coefficients (ICC) were calculated to indicate test-retest reliability and absolute agreement of results between the two methods.

RESULTS

Strong agreement between the interrupted and uninterrupted method was observed with ICCs ranging from 0.72 to 0.99 (supine) and 0.62-0.99 (semi-recumbent). Endpoint measures tended to be higher compared to baseline measures for all skin parameters. Differences in skin parameters results by anatomical location were evident particularly for erythema and stratum corneum hydration; the elbows and heels yielded lower scores compared to the sacrum. Erythema had the most variation across methods. The supine and semi-recumbent positions had negligible effect on measured skin parameters.

CONCLUSIONS

Minimal variation between skin parameter results indicates that brief off-loading in the interrupted method did not significantly change the outcomes; minor shifts in positioning do not alter changes to the skin from pressure. Skin parameters varied by anatomical location and changed over a 1 h period of pressure-loading.

RELEVANCE TO CLINICAL PRACTICE

Biophysical techniques may be able to assist accurate assessment of skin microclimate and skin colour. As brief off-loading (interruptions) to enable skin parameter measurement does not alter skin readings, researchers can proceed with some confidence regarding the use of this protocol in future studies assessing skin parameters. This study data provides a library of cutaneous changes at pressure-prone areas of healthy adults and is expected to inform innovative approaches to pressure injury risk assessment.

Preventing Pressure Injuries in Nursing Home Residents Using a Low-Profile Alternating Pressure Overlay: A Point-of-Care Trial

BACKGROUND

Pressure injuries (PIs) are a significant concern for patients with very limited mobility in skilled nursing facilities. Conflicting clinical guidelines and a lack of effectiveness data for the various support surfaces reduces the efficacy of PI prevention programs.

OBJECTIVE

To assess the preventive effectiveness (incidence of facility-acquired PIs) of a low-profile alternating pressure (AP) support surface plus facility-specific PI prevention programs in patients at high risk for PI.

DESIGN AND SETTING

Prospective, multicenter, point-of-care observational study in two for-profit nursing homes in the northeastern US.

PATIENTS AND INTERVENTION

A retrospective review of 101 residents was performed to determine baseline PI incidence. Then, a consecutive sample of 25 participants was selected based on the following eligibility criteria: high risk for PI, bedbound (20 hours or more per day), and stay in a mechanical ventilation unit for more than 5 days. The participants were placed on an AP overlay positioned above a facility-provided nonpowered reactive support surface.

MAIN OUTCOME MEASURE

The development of any new PI (stage 1-4), deep-tissue injury, or unstageable PI in participants using the AP overlay. The PI incidence for the AP group was compared with the retrospective baseline PI incidence from the same units in the two nursing homes.

MAIN RESULTS

The group using the AP overlay had a significantly lower PI incidence (0/25, 0%) compared with baseline (22/101, 21.8%; P < .001). Almost 80% of the study participants in the AP group were completely immobile, 100% of the participants were bowel- and bladder-incontinent, their average time on the AP overlay was 140.9 ± 94.1 days, and average length of stay in the facility was 633.9 ± 1,129.1 days.

CONCLUSIONS

The low-profile AP overlay was significantly more effective than facility-specific prevention programs alone in preventing PIs in a high-risk nursing home population over an extended period.

The mechanism of persistent undermining of a sacral pressure ulcer: Experimental analyses using a deformable model and examination of skin mobility over different anatomical locations

Undermining is an important issue in the treatment and care of deep pressure ulcers. The frequency of the undermining over different bony prominences varies. In particular, deep pressure ulcers over the sacrum exhibit undermining more frequently than those occurring over the heel. Although shear force has been suggested as a critical factor in undermining, the exact mechanism remains unclear due to ethical and technical reasons in clinical practice. To clarify this issue, a deformable model was constructed to recreate the physical and morphological properties of a pressure ulcer with persistent undermining. The model was constructed using urethane to recreate the physical properties of a pressure ulcer. To examine the clinical relevance of the model, mechanical properties of the skin and the model were measured using a durometer. The model was further mounted onto a phantom that was laid on a bed. Backrest elevation of the bed induced deformities in the urethane model, suggesting a mechanism of persistent undermining of the sacral pressure ulcer. Moreover, a simple palpation examination in elderly volunteers revealed that the skin over the sacrum was more mobile than the skin over the heel. Therefore, persistent undermining is likely caused by specific external forces and the characteristic skin mobility of the sacral region. These two different factors explain the frequent undermining that occurs in sacral pressure ulcers.

Prevention of Pressure Injury by Using Silicone Foam Dressings: Experience at a University Hospital in Hong Kong

Pressure injury is a serious problem and is common in critical care units. Over the last decade, there is new evidence suggesting that the use of multilayered silicone foam dressing as preventive measures can decrease the incidence and prevalence rate of hospital-acquired pressure injury. The purpose of this study was to investigate the clinical efficacy of this dressing in reducing sacral and coccygeal pressure injury incidence rate as compared with standard preventive interventions in critical care settings.

Predicting the Risk for Hospital-Acquired Pressure Ulcers in Critical Care Patients

BACKGROUND

Assessments of risk for pressure ulcers in critical care patients may not include important predictors.

OBJECTIVE

To construct risk-prediction models of hospital-acquired pressure ulcers in intensive care patients and compare the models' predictive validities with validity of the Braden Scale.

METHODS

Data were collected retrospectively on patients admitted to intensive care from October 2011 through October 2013. Logistic regression and decision trees were used to construct the risk-prediction models. Predictive validity was measured by using sensitivity, specificity, positive and negative predictive values, and area under the curve.

RESULTS

With logistic regression analysis, 6 factors were significant independent predictors. With the decision tree, 4 types of high-risk populations were identified. Predictive validity of Braden Scale scores was lower than the validities of the logistic regression and the decision tree models.

CONCLUSION

Risk for hospital-acquired pressure ulcers is overpredicted with the Braden Scale, with low specificity and low positive predictive value.

High frequency ultrasound sacral images in the critically ill: Tissue characteristics versus visual evaluation

PURPOSE

High frequency ultrasound (HFUS) systems may identify tissue injury. We compared HFUS tissue characteristics (dermal thickness and dermal density) with visual image examination.

METHODS

Longitudinal study in critically ill mechanically ventilated adults, from three ICUs (Surgical Trauma, Medical Respiratory, Neuroscience) enrolled within 24hours of airway intubation. Sacral HFUS images were obtained daily for up to seven days. Expert evaluation of the best image per day was completed and compared to HFUS generated tissue characteristics (dermal thickness and dermal density).

RESULTS

Of the113 subjects with 1614 comparisons analysed, 73.2% to 84% were normal, and 6.3% to 11.8% of the comparisons had injury present but no change was noted in the injury observed. There were no significant differences in one-day comparisons among type of injury and mean dermal thickness (p=0.6645) or dermal median intensity (adjusted p=0.06-0.17). All other day-to-day comparisons were similarly non-significant.

CONCLUSIONS

We found no association among dermal density, dermal thickness and visual examination of changes in sacral HFUS images for any day-to-day comparison. The use of sacral HFUS as a screening tool for the development of tissue injury is in its infancy. Additional comparative studies should be conducted to identify its future clinical usefulness.

Tissue interface pressure and skin integrity in critically ill, mechanically ventilated patients

OBJECTIVE

To describe tissue interface pressure, time spent above critical pressure levels and the effect on skin integrity at seven anatomical locations.

DESIGN, SETTING, PATIENTS

Descriptive, longitudinal study in critically ill mechanically ventilated adults, from Surgical Trauma ICU-STICU; Medical Respiratory ICU-MRICU; Neuroscience ICU-NSICU in a Mid-Atlantic urban university medical centre. Subjects were enroled in the study within 24hours of intubation.

MEASUREMENTS

Tissue interface pressure was measured continuously using the XSENSOR pressure mapping system (XSENSOR Technology Corporation, Calgary, Canada). Skin integrity was observed at all sites, twice daily, using the National Pressure Ulcer Advisory Panel staging system, for the first seven ICU days and at day 10 and 14.

RESULTS

Of the 132 subjects, 90.9% had no observed changes in skin integrity. Maximum interface pressure was above 32mmHg virtually 100% of the time for the sacrum, left and right trochanter. At the 45mmHg level, the left and right trochanter had the greatest amount of time above this level (greater than 95% of the time), followed by the sacrum, left and right scapula, and the left and right heels. Similarly, at levels above 60mmHg, the same site order applied. For those six subjects with sacral skin integrity changes, maximum pressures were greater than 32mmHg 100% of the time. Four of the six sacral changes were associated with greater amounts of time above both 45mmHg and 60mmHg than the entire sample.

CONCLUSIONS

Maximum tissue interface pressure was above critical levels for the majority of the documented periods, especially in the sacrum, although few changes in skin integrity were documented. Time spent above critical levels for mean pressures were considerably less compared to maximum pressures. Maximum pressures may have reflected pressure spikes, but the large amount of time above the critical pressure levels remains substantial.

Backrest Elevation and Tissue Interface Pressure by Anatomical Location During Mechanical Ventilation

BACKGROUND

Backrest elevations less than 30° are recommended to reduce pressure ulcers, but positions greater than 30° are recommended during mechanical ventilation to reduce risk for ventilator-associated pneumonia. Interface pressure may vary with level of backrest elevation and anatomical location (eg, sacrum, heels).

OBJECTIVE

To describe backrest elevation and anatomical location and intensity of skin pressure across the body in patients receiving mechanical ventilation.

METHODS

In a longitudinal study, patients from 3 adult intensive care units in a single institution receiving mechanical ventilation were enrolled within 24 hours of intubation from February 2010 through May 2012. Backrest elevation (by inclinometer) and pressure (by a pressure-mapping system) were measured continuously for 72 hours. Mean tissue interface pressure was determined for 7 anatomical areas: left and right scapula, left and right trochanter, sacrum, and left and right heel.

RESULTS

Data on 133 patients were analyzed. For each 1° increase in backrest elevation, mean interface pressure decreased 0.09 to 0.42 mm Hg. For each unit increase in body mass index, mean trochanter pressure increased 0.22 to 0.24 mm Hg. Knee angle (lower extremity bent at the knee) and mobility were time-varying covariates in models of the relationship between backrest elevation and tissue interface pressure.

CONCLUSIONS

Individual factors such as patient movement and body mass index may be important elements related to risk for pressure ulcers and ventilator-associated pneumonia, and a more nuanced approach in which positioning decisions are tailored to optimize outcomes for individual patients appears warranted.

Proxy study on minimizing risk of sacral pressure ulcers while complying with ventilator-associated pneumonia risk reduction guidelines

Bed positioning poses a subtle, yet important, tradeoff in the competing needs of hospitalized patients, particularly those susceptible to lower respiratory tract infections and/or pressure ulcers. Although it is widely held that a minimum 30° incline is necessary to mitigate risk of ventilator-acquired pneumonia, it is unclear what effect semirecumbent positioning has on the risk of pressure ulcerations. The authors test several hypotheses with the objective of elucidating the relationship between bed incline, posture, and incline, pursuant to a more evidence-based recommendation for practice in clinical care. To this end, interfacial pressures from 40 healthy subjects were analyzed following observation in both supine and sidelying positions, at shallow (30°) and moderate (45°) bed-angle incline. Summarily, the authors report that supine postures reduce pressure signatures associated with pressure ulceration versus sidelying position: 15% increase area of contact (P = 1.3×10), and 17% decrease in ratio of peak to average pressure (P = 3.1×10). Within supine posture, the authors found significant increases in 4 measures of local pressure, including average pressure (10.4% decrease, P = .005) and coefficient of pressure variation (22.1%, P = 2.2×10) at moderate incline. The authors conclude that supine bed positionings at moderate incline appear to reduce predictors of pressure ulceration.

Conventional versus neutral positioning in central neurological disease: a multicenter randomized controlled trial

BACKGROUND

Severe immobility due to lesions of the brain necessitates therapeutic positioning over the long term. There is little scientific evidence concerning the efficacy of different positioning methods. This clinical trial compares the effects of conventional positioning (CON) with those of positioning in neutral (LiN).

METHODS

A prospective, multicenter, investigator-blinded, randomized, controlled trial was performed on a total of 218 non-ambulatory patients (underlying disease: stroke, 141 patients; hypoxic brain damage, 28; traumatic brain injury, 20; other, 29). The subjects were randomly assigned to either LiN (105 patients) or CON (113 patients) and stratified within each of these two positioning concepts to five different positions. They remained in the assigned positions for two hours. The primary endpoint was change in the passive range of motion (PROM) of the hip joints. Secondary endpoints were change in the PROM of the shoulder joints and patient comfort.

RESULTS

Patients in the LiN group had a significantly better PROM of the hips after positioning than those in the CON group (difference, 12.84°; p<0.001; 95% confidence interval [CI], 5.72°-19.96°). The same was true for PROM of shoulder flexion (11.85°; p<0.001; 95% CI, 4.50°-19.19°) and external rotation (7.08°; p<0.001; 95% CI: 2.70°-11.47°). 81% of patients in the LiN group reported their comfort level as good, compared to only 38% in the CON group (p<0.001).

CONCLUSION

Positioning severely immobilized patients in LiN for two hours improved passive hip and shoulder mobility and patient comfort compared to conventional positioning. Further studies are needed to determine whether prolonged LiN positioning might improve rehabilitation and quality of life, prevent pressure sores, or ease nursing care.

The effectiveness of an oral health care program for preventing ventilator-associated pneumonia

AIMS AND OBJECTIVES

To determine the effectiveness of an oral health care program for preventing ventilator-associated pneumonia (VAP).

BACKGROUND

Research has shown a significant correlation between oral bacteria and VAP, indicating that an oral health care program plays a very important role in VAP prevention.

DESIGN AND METHODS

A quasi-experimental study was used and conducted in the intensive care unit in a medical centre. A total of 199 mechanically ventilated patients were enrolled and divided into two groups: the experimental group (n=99) and control group (n=100). The experimental group was cared for using an evidence-based oral health care program, and the control group was cared for using routine nursing care procedures. Each group received the assigned treatment for four consecutive days.

RESULTS

The incidence of VAP in the experimental group (4%, 4/95) was significantly lower than that in the control group (21%, 18/82). The oral assessment guide (OAG) mean score (9.16 ± 2.07) of the experimental group was significantly different (P<0.05) from that of the control group (10.07 ± 1.79). The general estimated equation further showed that there was a significant difference between groups (P<0.01) for the third post-test data and no significant difference for the pre-test or the first and second post-test data between groups, indicating that an increased duration of intervention resulted in significant decreases in the OAG scores in the experimental group compared with the control group.

CONCLUSIONS

The evidence-based oral health care program effectively improved oral mucosal health and statistically reduced the incidence of VAP in this study.

RELEVANCE TO CLINICAL PRACTICE

The study findings may be useful as an empirical reference for health care professionals performing an oral health care program in the future. Additionally, it may serve as a reference for long-term care policies aimed at reducing the ventilation duration, days of hospitalization and mortality rate to enhance patient safety and the quality of medical care.