The impact of exposure time on biophysical parameters of the wound environment and patient comfort during dressing changes: a descriptive study.

Abstract

Wound healing is a complex milieu that affects millions of people around the world every day. Practice based concerns have been described anecdotally by nurses in acute care facilities where wounds requiring an assessment by health care professionals have been left without their primary dressings for a considerable length of time. A number of studies have demonstrated that the temperature, transepidermal water loss (TEWL) and pH of a wound's microenvironment influence wound healing; however, there is limited research on the effect of the dressing changes on these parameters as well as the risk of contamination of the wound through prolonged exposure. The impact of prolonged exposure throughout delays in a dressing change on these biophysical wound bed parameters and the possible contamination of the wound during the wound dressing procedure; and the affect delays have on patient pain, comfort and activities of daily living, were investigated through a descriptive correlational study. Demographics and participant questionnaire data were analysed using descriptive statistics and frequency distributions. Patterns of distribution of the wound temperature, TEWL and pH data were reviewed before being further analysed along with the bacterial and patient questionnaire data using Generalised Estimating Equations regression models. A GEE linear regression model was used for normally distributed data; and GEE logistic regression models for data which were not normally distributed, using the Statistical Analysis System (SAS) 9.3. The results identified that the participants’ wounds were hypothermic as well as alkaline at dressing removal and throughout the period of exposure. The mean wound temperature increased throughout the total duration of the down time which was contrary to expectation, although despite this all wounds remained hypothermic. The pH became more alkaline with the chance of having a pH of >8.5, 12% higher than having a pH of <8.5. There was no relationship between the size of the wound and any of the wound bed parameters; however, there was a relationship between the type of wound, the temperature and pH. No associations could be made in regards to the participant’s body temperature and wound temperature. In addition to the investigation into the wound bed parameters, agar plates placed in proximity to the exposed wounds grew pathogens which could potentially contaminate the wound. The third issue investigated was the affect wound dressing changes on the participant's pain, comfort and activities of daily living, an important aspect of the holistic approach to patient care. Participants were noted to be unable to perform some activities of daily living; including hygiene, toileting, nutrition and positioning during the wound down time. Analgesia was offered haphazardly despite the majority of patients having a pain score pre dressing removal that would indicate analgesia was required and an associated increase in their pain score during the dressing procedure. The impact of delayed wound dressing changes on the patient’s activities of daily living and pain are important in the delivery of patient centred care; however the major findings of the study relate to the poor state of the wounds immediately following removal of the dressing. Hypothermic, alkaline wound beds are not conducive to healing and warrant further investigation.