Microclimate analysis can gauge patients’ pressure ulcer risk7th May 2013
Yusurf S, Okuwa M, Shigeta Y, et al (2013) Microclimate and development of pressure ulcers and superficial skin changes. Int Wound J 2013 Mar 12. doi: 10.1111/iwj.12048. [Epub ahead of print]
This article examines the role of the microclimate in the formation of pressure ulcers considering skin temperature and the moisture between the skin and the supporting surface. The authors point out that this is an area that has not been investigated, although it has been shown that skin temperature rises slightly in the days before pressure damage occurs. Increased moisture or excessive dryness has also been show to cause damage to the skin. The skin’s interaction with the surface it is next to can also affect pressure ulcer formation.
This study was carried out in a hospital in Indonesia that had beds consisting of foam mattresses covered in plastic covered by either a 100% cotton sheet or a sheet of 42% cotton and 58% polyester. People included in the study showed no sign of pressure damage before admittance to the hospital but developed pressure damage measured on the Braden scale as 18 or lower.
Skin temperature (using a digital thermometer) and skin moisture (using a Corneometer) was measured at the sacrum and just below the umbilicus as a control. Measurements were made every three days from admittance and collated along with other data. Room climate was measured using a hygrometer and interface pressure was measured using a multiface sensor.
Data was analysed from 71 participants, 20 developed pressure ulcers and skin changes while 51 did not. When comparing the difference between total skin temperature between the sacrum and the control area, the authors found it to be marginally significant in the group with skin changes compared with those with no skin changes. All the significant differences between the two groups were subjected to multivariate analysis and two risk factors for skin damage were found to be significant: type of sheet and the Braden scale score.
The authors found that microclimate was related to skin tolerance problems. In the discussion they say that increased temperature may be due to prolonged pressure causing occlusive skin blood flow and inflammation, and accumulation between sacrum skin and support surfaces. They suggest that the plastic covers may have made the microclimate temperature rise.
Skin moisture was found to be similar in the sacral area in both groups, which was probably due to a high room temperature.
Of all the patients who had skin changes, 85% used a bedsheet made of 100% cotton. The cotton/synthetic fibre was able to diffuse moisture away from the skin and so reduced the coefficient of friction, and those patients using a cotton bedsheet were found to be at higher risk of pressure ulcer formation.
The authors admitted several study limitations and stated that a large number of participants dropped out of the study. The high humidity of the wards was a problem, they were only able to take samples from 2–3 participants a day, and interface pressure data was only collected from 33 participants. Despite these limitations, the authors conclude that a rise in skin temperature can be an indicator of a higher risk of pressure ulcer formation. This information is particularly useful for patients with a darker skin tone when erythema is not as evident. They also say that a synthetic sheet could be beneficial when controlling microclimate.