It is estimated that it takes an average of 17 years for evidence to be put into practice (Balas & Boren 2000). Implementation of evidence-based practice (EBP) should be the goal for all perioperative professionals. However, where evidence is scant, we must rely on all practices that constitute EBP. A conceptual model proposed by Melnyk & Fineout-Overholt (2003) guides clinical decision-making based on three areas:
1. Research evidence and evidence based theories.
2. Clinical expertise and evidence from patient assessment history, condition and available resources.
3. Patient preference and values. All of these must be considered to improve quality outcomes.
The body of research evidence related to the prevention of pressure ulcers (PU) has just grown with the publication of the Pressure Ulcer Prevention: Quick Reference Guide. Published by the European Pressure Ulcer Advisory Panel and National Pressure Ulcer Advisory Panel in 2009, it is the most current review of the research literature on pressure ulcers to date. The section on “Special Population: Patients in the Operating Room” will be discussed here. The Strength of Evidence scoring for recommendations in these guidelines uses an A, B, C rating.
A rating means: “The recommendation is supported by direct scientific evidence from properly designed and implemented controlled trials on pressure ulcers in humans (or humans at-risk for pressure ulcers), providing statistical results that consistently support the guideline statement. (Level 1 studies required)
B rating means: “The recommendation is supported by direct scientific evidence from properly designed and implemented clinical series on pressure ulcers in humans (or humans at-risk for pressure ulcers); providing statistical results that consistently support the recommendation. (Level 2, 3, 4, 5 studies required)
C rating means: “The recommendation is supported by indirect evidence (e.g., studies in normal human subjects, humans with other types of chronic wounds, animal models) and/or expert opinion.”
Patient preferences for positioning may be difficult due to the prescriptive nature of surgical positioning. However, patients should expect to recover from surgery without adverse events from poor pressure management or positioning practices.
Key recommendations (bolded) in this document include:
1. Refine risk assessment of individuals undergoing surgery by examining other factors that are likely to occur and will increase risk of pressure ulcer development, including:
- Length of the operation.
- Increased hypotensive episodes intra-operatively.
- Low core temperature during surgery.
- Reduced mobility on day one post-op.
Currently, a validated risk assessment tool for the operating room does not exist. However, in a study conducted by Scott-Williams, several factors emerged as significant, including:
- Age >62.
- Albumin less than 3.5
- ASA score 3 or greater.
By also adding the factor of time on the table, these “Scott Triggers” are currently being researched in several settings for application to identify the “high-risk” surgery patient and implement prevention strategies.
2. Use a pressure-redistributing mattress on the operating table for all individuals identified as being at risk of pressure ulcer development. (Strength of Evidence = B) Several operating room support surfaces that encourage pressure redistribution have been developed. At present, there is not enough available evidence to recommend the most effective interventions for pressure redistribution on the OR table. However, it’s clear that the standard table pad — 2" elastic foam with a laminate cover — is a significant risk factor for increased PU incidence compared to newer technologies. When developing a comprehensive PUP program for the OR, the first step is to evaluate the OR table pads and consider an upgrade. New products are thicker (3-1/2 to 4") and combine multi-layered technology, such as visco-elastic and various densities of foam, to provide pressure redistribution and prevent the patient from “bottoming out.” These types of OR table pads should be the minimal requirement for a prevention program.
If a facility has known deep tissue injuries after surgery, or serves a high-risk patient population, more advanced technologies are available for a price. The debate over cost of technology versus higher quality of care continues, but dealing with patient suffering and multimillion-dollar lawsuits are an undesirable alternative.
One such technology is Fluid Immersion Simulation®. This dynamic device simulates the effects of a body “floating” in a fluid, thus alleviating vertical shear forces, which deform soft tissue. It incorporates concepts from physics like Boyle’s Law (air viscosity) and the Archimedes Principal (buoyancy) into algorithms that simulate immersion in a fluid. By using a microprocessor and sophisticated software, the system is able to analyze in a three dimensional volumetric format the anthropometric characteristics (shape) of a patient on the mattress. The device self-adjusts to maximize pressure redistribution over all body surfaces. With a weight limit of 1,800 lbs., it provides a safe alternative to high-risk procedures of over 4 hours.
Efficacy studies on this technology are not complete, but users are reporting a decrease in perioperative pressure ulcer incidence. Both CT and PET scans have been used along with perfusion studies to demonstrate reduction in tissue deformity and the ability to maintain micro-circulation to peripheral tissue which is critical when trying to prevent deep tissue injury.
3. Position the patient in such a way as to reduce the risk of pressure ulcer development during surgery. (Strength of Evidence = C)
4. Elevate the heels completely (off-load them) in such a way as to distribute the weight of the leg along the calf without putting all the pressure on the Achilles tendon. The knee should be in slight flexion. (Strength of Evidence = C) Hyperextension of the knee may cause obstruction of the popliteal vein, and this could predispose the individual to deep vein thrombosis. This can be achieved by using heel off-loading devices (HOLD) that redistribute the pressure along the lower leg while suspending the heel. Avoid devices not intended for pressure redistribution, such as towel rolls or IV bags, to off-load the heel, as this can hyperextend the knee. Consider placing the HOLD device in the OR and have it follow the patient into the post-operative setting for high-risk patients. In a recent QI study, this practice was successful in a small population of high-risk patients.
5. Pay attention to pressure redistribution prior to and after surgery. (Strength of Evidence = C)
- Place the individual on a pressure-redistributing mattress both prior to and after surgery. (Strength of Evidence = C) In my experience, “Universal Pressure Precautions,” such as using integrated air surfaces or pressure redistribution mattresses for all patients in the pre- and post-op areas, has been effective in reducing hospital-acquired PUs. It is equally important to track adverse events such as pressure and nerve injuries to the perioperative setting. Many OR nurses report they have never witnessed a pressure injury in their patients, but when asked if they perform daily skin assessments after surgery, the answer is no.
- Position the individual in a different posture pre-operatively and post-operatively than the posture adopted during surgery. (Strength of Evidence = C) This particular finding has great potential for change in nursing practice. Educating pre-operative nurses in areas such as holding, surgical units and ICUs about the planned surgical position and time on the table can help create a proactive approach to prevention.
Though these guidelines offer new evidence for the OR, there is a great need for future study related to efficacy of devices and practices related to positioning the patient to reduce injury during surgery. The future of pressure technology would include advanced surfaces in all OR and procedure table pads.
— Susan Scott-Williams, MSN, RN, CWOCN
Ms. Scott-Williams (firstname.lastname@example.org) is the acute care specialist for the South Central Veterans Health Care Network (VISN 16) in Ridgeland, Miss.
Disclaimer: The opinions expressed in this article are those of the author and do not necessarily reflect those of the Department of Veterans Affairs.
Balas E. A. & Boren S.A. (2000) Managing clinical knowledge of healthcare improvements. In V. Schattauer (Ed.), Yearbook of medical informatics, (pp. 65-70). Stuttgart, German: Schattauer.
Fineout-Overholt. E. & Johnston L, (2006) Teaching EBP: Implementation of Evidence: Moving from Evidence to Action. Fourth Quarter Worldviews on Evidence-based Nursing p 194-200.
European Pressure Ulcer Advisory Panel and National Pressure Ulcer Advisory Panel. Prevention and treatment of pressure ulcers: quick reference guide. Washington DC: National Pressure Ulcer Advisory Panel; 2009. http://www.epuap.org/guidelines/Final_Quick_Prevention.pdf
Fluid Immersion Simulation® is used in a device called the Dolphin Pad®. Both are registered trademarks of Biologics, Inc.