Best-practices for preventing skin injury beneath personal protective equipment during the COVID-19 pandemic: A position paper from the National Pressure Injury Advisory Panel.

COVID-19 has infected millions of patients and impacted healthcare workers worldwide. Personal Protective Equipment (PPE) is a key component of protecting frontline clinicians against infection. The benefits of PPE far outweigh the risks, nonetheless, many clinicians are exhibiting skin injury caused by PPE worn incorrectly. These skin injuries, ranging from lesions to open wounds are concerning because they increase the susceptibility of viral infection and transmission to other individuals. Early into the COVID-19 pandemic (April 2020), the U. S. National Pressure Injury Advisory Panel (NPIAP) developed a series of position statements to improve wear-ability of PPE and protect healthcare professionals and their patients as safe from harm as possible under the circumstances. The NPIAP positions, which were formed by conducting a systematic review of what was known at the time, include: (a) Prepare skin before and after wearing PPE with skin sealants, barrier creams and moisturisers; (b) Frequent PPE offloading to relieve pressure and shear applied to skin; (c) treat visible skin injuries immediately caused by PPE to minimise future infection; (d) non-porous dressings may provide additional skin protection, but lack evidence; (e) health systems should take care to educate clinicians about placement and personal hygiene related to handling PPE. Throughout all of these practices, handwashing remains a top priority to handle PPE. These NPIAP positions provided early guidance to reduce the risk of skin injury caused by PPE based on available research regarding PPE injuries, a cautious application of evidence-based recommendations on prevention of device-related pressure injuries in patients and the expert opinion of the NPIAP Board of Directors. Clinicians who adhere to these recommendations reduce the prospects of skin damage and long-term effects (e.g. scarring). These simple steps to minimise the risk of skin injury and reduce the risk of coronavirus infection from PPE can help.

Validating a wheelchair in-seat activity tracker.

Wheelchair users often experience prolonged periods of stationary sitting. Such periods are accompanied with increased loading of the ischial tuberosities. This can lead to the development of pressure ulcers which can cause complications such as sepsis. Periodic pressure offloading is recommended to reduce the onset of pressure ulcers. Experts recommend the periodic execution of different movements to provide the needed pressure offloading. Wheelchair users, however, might not remember to perform these recommended movements in terms of both quality and quantity. A system that can detect such movements could provide valuable feedback to both wheelchair users as well as clinicians. The objective of this study was to present and validate the WiSAT - a system for characterizing in-seat activity for wheelchair users. WiSAT is designed to detect two kinds of movements - weight shifts and in-seat movements. Weight shifts are movements that offload pressure on ischial tuberosities by 30% as compared to upright sitting and are maintained for 15 seconds. In-seat movements are shorter transient movements that involve either a change in the center of pressure on the sitting buttocks or a transient reduction in total load by 30%. This study validates the use of WiSAT in manual wheelchairs. WiSAT has a sensor mat which was inserted beneath a wheelchair cushion. Readings from these sensors were used by WiSAT algorithms to predict weight shifts and in-seat movements. These weight shifts and in-seat movements were validated against a high-resolution interface pressure mat in a dataset that resembles real-world usage. The proposed system achieved weight shift precision and recall scores of 81% and 80%, respectively, while in-seat movement scores were predicted with a mean absolute error of 22%. Results showed that WiSAT provides sufficient accuracy in characterizing in-seat activity in terms of weight shifts and in-seat movement.

Everyday use of power adjustable seat height (PASH) systems.

The objective of this study was to measure how, why, and where the power adjustable seat height (PASH) system of Quantum's iLevel® wheelchairs were used. We instrumented iLevel® power wheelchairs for 24 adults to measure wheelchair occupancy, seat height, in-seat activity level, and bouts of mobility. Participants elevated their wheelchair 3.9 (4.4) (mean (SD)) times per day, including 1.0 (1.6) times per day past 9". Twenty-nine percent of elevation events were transient, lasting < 1 min, while 42% of elevate events lasted >5 minutes. Sixty-seven percent of participants transferred while elevated at least once, typically from heights <5" or >9", and 14 people changed their seat height between the transfer to and from the wheelchair. Twenty-three of 24 participants wheeled while elevated. Finally, in-seat activity level was greater while elevated. For many participants, the PASH system provided a functional benefit on a daily basis. Individuals elevated 4 times per day for activities including transfers, reach, gaze, or mobility. However, 14 participants did not elevate on at least 1 day. Further study is needed to identify the characteristics of people who will benefit most from a PASH system as well as to document the value associated with PASH system use.

Seated buttocks anatomy and its impact on biomechanical risk.

AIM: The objective of this study was to describe the amount, types, and shapes of tissue present in the buttocks during sitting (i.e., seated buttocks soft tissue anatomy), and the impact of seated buttocks soft tissue anatomy on biomechanical risk. MATERIALS AND METHODS: The buttocks of 35 people, including 29 full-time wheelchair users with and without a history of pelvic pressure ulcers were scanned sitting upright on 3" of flat HR45 foam in a FONAR Upright MRI. Multi-planar scans were analyzed to calculate bulk tissue thickness, tissue composition, gluteus maximus coverage at the ischium, the contour of the skin, and pelvic tilt. RESULTS: Bulk tissue thickness varied from 5.6 to 32.1 mm, was composed mostly of adipose tissue, and was greatest in the able-bodied cohort. Skin contours varied significantly across status group, with wheelchair users with a history of pressure ulcers having tissue with a peaked contour with a radius of curvature of 65.9 mm that wrapped more closely to the ischium (thickness at the apex = 8.2 mm) as compared to wheelchair users with no pressure ulcer history (radius of curvature = 91.5 mm and apex thickness = 14.5 mm). Finally, the majority of participants presented with little to no gluteus coverage over their ischial tuberosity, regardless of status group. CONCLUSIONS: This study provides quantitative evidence that Biomechanical Risk, or the intrinsic characteristic of an individual's soft tissues to deform in response to extrinsic applied forces, is greater in individuals at greater risk for pressure ulcers.

Measuring the impact of cushion design on buttocks tissue deformation: An MRI approach.

AIM: To establish a research approach for describing how different wheelchair cushion designs impact buttocks tissue deformation during sitting. MATERIALS AND METHODS: The buttocks of 4 individuals with spinal cord injury and significant atrophy were scanned sitting in a FONAR Upright MRI. Scans were collected with the individuals' buttocks fully suspended without pelvic support, and seated on 3 different commercially available wheelchair cushions. Multi-planar scans were analyzed to provide 3D renderings and measurements of tissue thickness and shape. RESULTS: Bulk tissue thicknesses at the ischium, which rarely included muscle, were reduced by more than 60% on enveloping cushion designs studied (i.e., Roho HP and Matrx Vi), and more variably (23-60%) on an orthotic off-loading design (i.e., Java). Adipose was typically displaced posterior and superior from the unloaded condition, with more lateral displacement on the Roho HP and Matrx Vi and more medial displacement present on the Java. Large changes in angle at the sacro-coccygeal joint indicated significant loading on the region. Deformation at the greater trochanter was more consistent across surfaces. Greater interface pressures tended to be associated with greater deformation, but the relationship varied by individuals and was highly non-linear. CONCLUSIONS: The buttocks in this study all deformed significantly, but at different locations and in different manners across all 3 surfaces. Attention needs to be paid to the regions of greatest deformation. A future metric of shape compliance should consider cushion performance at all high risk regions, and changes to the amount and shape of tissue in the regions of interest.

Some people move it, move it for pressure injury prevention.

OBJECTIVE: To describe differences in in-seat behavior observed between individuals with a spinal cord injury (SCI) with and without a history of recurrent pressure injuries. DESIGN: Cross-sectional cohort study. SETTING: General community. PARTICIPANTS: Twenty-nine adults more than 2 years post SCI, who used a wheelchair as their primary mobility device and had the ability to independently perform weight shift maneuvers. Participants were grouped according to whether or not they had a history of recurrent pressure injuries (PrIs), with 12 subjects having had two or more pressure injuries in the pelvic area (PrI Group). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Daily time in wheelchair, number of transfers, and frequency of pressure reliefs (full unloading), weight shifts (30% load reduction), and in-seat movements (transient center of pressure movements or unloading). RESULTS: The median participant spent 10.3 hours in his wheelchair and performed 16 transfers to or from the wheelchair daily. Pressure reliefs were performed less than once every 3 hours in both groups. Weight shifts were performed significantly more often by the No PrI Group (median (interquartile range) 2.5 (1.0-3.6) per hour) than the PrI Group (1.0 (0.4-1.9), with P = 0.037 and effect size r = 0.39). In-seat movements were performed 46.5 (28.7-76.7) times per hour by the No PrI group and 39.6 (24.3-49.7) times per hour for the PrI group (P = 0.352, effect size r = 0.17). CONCLUSION: Weight shifts that can be produced by functional activities and that partially unload the buttocks should be considered as an important addition to individuals' PrI prevention regimen.

Everyday sitting behavior of full-time wheelchair users.

The objective of this study was to describe the in-seat movement and weight-shifting behavior of full-time wheelchair users. We measured everyday sitting behavior for 192 d across 28 individuals who used manual wheelchairs as their primary mobility device. To obtain the measurements, we used eight thin force sensors placed under participants' wheelchair cushions. On a typical day, participants spent an average of 10.6 +/- 3.0 h in their wheelchair and transferred out of the wheelchair 8.4 +/- 4.3 times. Participants only performed pressure reliefs (90% off-loading of the entire buttocks for at least 15 s) 0.4 +/- 0.5 times per hour they were seated in the chair, but they performed weight shifts (WSs) (30%-90% off-loading of at least one side of the buttocks for 15 s) with a frequency of 2.4 +/- 2.2 times per hour. Despite the higher frequency of WSs, they were not performed in a routine manner. Half of the days studied included one segment of upright sitting lasting at least 2 h without a WS. Given these observations, we conclude that seating evaluations should emphasize positioning individuals in a way that facilitates reaching, leaning, and transferring in a safe manner, not only to improve function but also to affect buttocks loading.

Effects of wheelchair cushions and pressure relief maneuvers on ischial interface pressure and blood flow in people with spinal cord injury.

OBJECTIVE: To investigate the effectiveness and interactions of 2 methods of pressure ulcer prevention, wheelchair cushions and pressure relief maneuvers, on interface pressure (IP) and blood flow of the buttocks. DESIGN: Within-subject repeated measures. SETTING: Rehabilitation center. PARTICIPANTS: Wheelchair users with a spinal cord injury or disorder (N=17). INTERVENTIONS: Participants performed 3 forward leans and 2 sideward leans with different degrees of lean while seated on each of 3 different wheelchair cushions. MAIN OUTCOME MEASURES: IP measured with a custom sensor and blood flow measured with laser Doppler flowmetry were collected at the ischial tuberosity. RESULTS: Pressure relief maneuvers had a significant main effect on the ischial IP (P<.001); all maneuvers except for the small frontward lean resulted in a significant reduction in IP compared with upright sitting. Blood flow significantly varied across postures (P<.001) with flow during upright sitting and small forward leans being significantly lower than during the full and intermediate leans in both the forward and sideward directions. CONCLUSIONS: The results of the study highlight the importance of positioning wheelchair users in a manner that facilitates in-seat movement. Regardless of the cushion being used, the pressure relief maneuvers resulted in very large reductions in IPs and significant increases in buttock blood flow. Only the small frontward lean was shown to be ineffective in reducing pressure or increasing blood flow. Because these pressure relief maneuvers involved postural changes that can occur during functional activities, these pressure relief maneuvers can become a part of volitional pressure relief and functional weight shifts. Therefore, clinical instruction should cover both as a means to impart sitting behaviors that may lead to better tissue health.

The impact of tilting on blood flow and localized tissue loading.

AIM OF THE STUDY: The overall goal of this research was to improve the use of seated tilt to increase function, health and quality of life for people using power wheelchairs. Specifically, the objective of this study was to evaluate the biomechanical responses to seated full body tilt in persons with spinal cord injury (SCI). MATERIALS AND METHODS: Laser Doppler Flowmetry and interface pressure measurement were employed to measure changes in blood flow and loading at the ischial tuberosities across different amounts of tilt. Eleven participants with SCI were studied in a laboratory setting. RESULTS: Results showed that biomechanical responses to tilt were highly variable. Pressure reduction at the ischial tuberosity was not present at 15°, but did occur with tilts to 30° and greater, and could be explained by the tilt position and upright pressure. Unlike pressure, blood flow increased with all tilts from an upright position, but did not increase when tilting from 15° to 30°. Only 4 of 11 participants had increases in blood flow of ≥10% at 30° tilt, whereas 9 participants did during maximum tilt (i.e., 45°-60°). CONCLUSIONS: Based on the results of this study, tilting for pressure reliefs as far as the seating system permits is suggested to maximize the potential for significant blood flow increases and pressure relief. The use of interim small tilts is also supported, as they also provide some benefit.

Characterization of power wheelchair use in the home and community.

OBJECTIVE: To characterize the use of power wheelchairs and to determine if multiple measures of mobility and occupancy jointly provide a more comprehensive picture of wheelchair usage and daily activity in full-time power wheelchair users than daily distance alone. DESIGN: Prospective observational study. SETTING: Subjects' everyday mobility was measured in their homes and communities for 2 weeks, and prompted recall interviews were conducted by phone. PARTICIPANTS: A convenience sample (N=25) of nonambulatory, full-time power wheelchair users. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Wheelchair usage was logged electronically, and geolocation and interview data were used to isolate chair use to (1) in the home, (2) not in the home indoors, or (3) outdoors. Distance wheeled, time spent wheeling, number of bouts, time spent in the wheelchair, and the percentage of time in the wheelchair spent wheeling were measured to describe wheelchair use. RESULTS: The median wheelchair user spent 10.6 hours (range, 5.0-16.6h) in his/her wheelchair daily and wheeled 1.085 km (range, 0.238-10.585 km) over 58 minutes (range, 16-173 min) and 110 bouts (range, 36-282 bouts). Wheelchair use varied across subjects, within subjects from day to day, and between environments. Mobility bouts outdoors were longer and faster than those wheeled indoors. In a regression analysis, distance wheeled explained only 33% of the variation in the number of bouts and 75% in the time spent wheeling. CONCLUSIONS: Power wheelchair use varies widely both within and between users. Measuring distance, time, and number of bouts provides a clearer picture of mobility patterns than measuring distance alone, whereas occupancy helps to measure wheelchair function in daily activities.

In vivo elongation of the palmar and dorsal scapholunate interosseous ligament.

PURPOSE: To investigate the elongation of the palmar and dorsal subregions of the scapholunate interosseous ligament (SLIL) in healthy human subjects throughout a complete range of wrist motion. METHODS: The 3-dimensional in vivo kinematics of the scaphoid and lunate were determined in both wrists of 13 female and 13 male volunteers from computed tomography volume images. For each wrist the palmar and dorsal insertions of the SLIL were identified on reconstructed surface models of the scaphoid and lunate. The interbone distances between the palmar and dorsal sites were calculated for the neutral wrist position. Elongations were then calculated after applying the 3-dimensional kinematics to the scaphoid and lunate. A multiple linear regression model was used to determine if elongations varied significantly as a function of wrist flexion/extension and radioulnar deviation. RESULTS: From pure wrist extension to pure wrist flexion, the fibers of the SLIL at the palmar insertion site increased significantly, from 29% shortening to 27% elongation, and the dorsal insertion decreased from 26% to 4% shortening with respect to the fiber lengths in the neutral position. From pure radial deviation to pure ulnar deviation, the elongation of the palmar insertion significantly decreased from 9% elongation to 21% shortening. There was no notable change in dorsal elongation with wrist radioulnar deviation. The multiple linear regression model predicted that there would be minimal elongation of the palmar and dorsal fibers at the wrist position along the dart thrower's path from radial extension to ulnar flexion. CONCLUSIONS: In vivo elongation of the palmar and dorsal fibers of the SLIL varied with wrist position. The palmar fibers lengthened and the dorsal fibers shortened with wrist flexion and the opposite occurred with wrist extension. Scapholunate interosseous ligament elongation was minimal as the wrist was positioned along the dart thrower's path.