By Ajay Gupta, Ram V. Nayak
Foam, unlike gel, with air gaps, bottoms out leaving undue pressure on surgical sites.
World has shifted to advance technologies in prevention of pressure sores...
Patient’s Safety is a major responsibility of OT operator and it is critically linked to selection of right type of Positioning Devices. One of the important extrinsic factor attributes towards pressure injuries is prolonged surface interface pressure. Operation Theatre Positioning Devices across the globe are made up of different material. The first and foremost is selection of material. The commonly available and most economical raw material is foam. In this blog, we are attempting to compare scientific evidence related to limitation of Foam in OT Positioning Devices. The commercial variants use ranging from low- high density Polyurethane Foam (1.05-1.3 lb/cu.cm).
Studies conducted by Macky (2006) explained that foam generally bottoms out. It is referred as condition when the foam gets fully compressed under the weight of patient’s body such that resultant outcome leads to no pressure re-distribution [Web Link: https://pubmed.ncbi.nlm.nih.gov/15924893/].
Another study found that additional padding with convoluted foam (e.g. egg crate) padding did not reduce the pressure (Suttonet al, 2013; https://www.pubfacts.com/author/Shauna+Sutton). McNichol & coworkers (2015) suggested that evidence correlation patient’s pressure re-distribution (resultant prevention of pressure injury) with optimal foam density is lacking https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4845766/. However, use of gel (viscoelastic polymer) distribute pressure more evenly.
AORN reports in the 2020 Guideline for Positioning the Patient (7.5) that static surfaces such as viscoelastic polymer (i.e gel) overlays are designed to reduce shearing and to support the patient’s weight without becoming fully compressed under the weight of the patient’s body. Gel overlays and positioning devices are radiolucent, latex-free, and reusable. Thus, among other benefits, gel is a good solution to the “bottom out” effect that causes undue pressure and sheer (Latest Report of 2022, web link: https://www.aorn.org/guidelines/about-aorn-guidelines?utm_source=bing&utm_medium=cpc&utm_campaign=guidelines_2022&msclkid=cd6d7881792c13ca78cf1a5fc7fcce7d). This above-mentioned information is available on Blog by companies that are developing OT Positioning Devices using gel of different composition (see web reference: Action Products Blog - Foam or Gel for Patient Position: What Does the Evidence Say?).
The underlying facts common to all Foam based OT Positioners is that (a) generally single use; (b) associated with issue of bottom due being open cell structure allowing air to flow in; (c) density function variability that is linked to site for which it can be used or not becomes another decision to be made by OT Operator responsible for patient’s safety; (d) non-reusable, thus managing contamination factor is also extremely difficult.
Viscoelastic Gel Polymer (aka Medigel with density of 4.99 lb/cu.cm as well as Shore O value limits to Zero) based OT Positioning Devices that can even be used directly without any film, REACH certified are extremely useful in OT Positioning Devices in prevention of injuries.