Tissue electrical properties monitoring for the prevention of pressure sore.
BACKGROUND
Pressure sores are a significant problem in the healthcare sector. Although they may cause considerable morbidity, they are preventable.


OBJECTIVE
The objectives of this study are to (1) investigate the electrical properties of a tissue close to and away from the pressure sore site, and (2) establish a new approach for objective, reliable, low-cost and noninvasive screening or detection of pressure sore in its early stage.


METHODS
Randomised controlled trial.


METHODS
Fifteen patients participated in this study. They all had stage I or stage II sacral pressure sores. Tiny surface electrodes in four-electrode configuration were used for all tissue electrical properties measurements recorded over the frequency range of 30-10 MHz.


RESULTS
Intraclass correlation coefficient (ICC) showed that all measurements (ICC > 0.90 for all measurements) had good reliability and validity. The real part of impedance (R) and the imaginary part of impedance (X) of a tissue measured close to the pressure sore site was found to be significantly smaller (p < 0.05 in all cases) than that measured away from the pressure sore site at a specific frequency range (R: 30.00-38.55 Hz; X: 43.95-606.40 Hz). It was also found that the extracellular resistance (R(e)) and the ratio of extracellular resistance to intracellular resistance (R(e)/R(i)) of a tissue measured close to the pressure sore site were significantly smaller (p < 0.05 in all cases) than that measured away from the pressure sore site.


CONCLUSIONS
Since the electrical properties (R, X, R(e), R(e)/R(i) ) of a tissue close to, and away from, the pressure sore site can be significantly distinguished, a potentially promising method for the screening of pressure sores at an early stage has been proposed.
National Chi Nan University, Puli, Taiwan. tsching@ncnu.edu.tw
Congo Tak-Shing
CT
Ching
Mei-Yun
MY
Chou
Siou-Jhen
SJ
Jiang
Su-Hua
SH
Huang
Tai-Ping
TP
Sun
Wei-Hao
WH
Liu
Chia-Ming
CM
Liu
D000368:Aged; D000369:Aged, 80 and over; D017097:Electric Impedance; D004566:Electrodes; D055724:Electrophysiological Phenomena / Q000502:physiology*; D004594:Electrophysiology / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D008954:Models, Biological; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods*; D003668:Pressure Ulcer / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control*; D015203:Reproducibility of Results; D012307:Risk Factors; D012720:Severity of Illness Index; D040521:Subcutaneous Tissue / Q000502:physiology*