The viability of soft tissues in elderly subjects undergoing hip surgery.

Aims: To assess the viability of soft tissues in elderly patients subjected to prolonged support pressures.

Design: measurements were performed on the soft tissues of patients undergoing surgery for fracture of the proximal femur.

Methods: 10 subjects, mean age 84 years, participated. Transcutaneous gas tensions were continuously monitored in an area adjacent to the contralateral greater trochanter, which was loaded with an external applicator. Subcutaneous interstitial pressures using a slit catheter were also measured.

Results: Transcutaneous oxygen partial pressure fell in some patients to critically low levels, defined as below 2.7 kPa (20 mmHg), whilst they were subjected to normal interface pressures on the operating table. Transcutaneous partial carbon dioxide pressures rarely rose above 8.0 kPa (60 mmHg). The measured interstitial pressures could lead to local occlusion of skin microvessels.

Conclusions: This study confirms that tissue viability could be compromised in elderly patients undergoing surgical procedures. The methods employed may be of value in assessing support surfaces in the operating theatre to reduce the incidence of pressure sores in this high-risk patient group.