Bioimpedance spectroscopy is a valid and reliable measure of edema following hand burn injury (Part 1-method validation)

Abstract

The assessment of swelling following burn injury is complicated by the presence of wounds and dressings and due to patients experiencing significant pain and impaired movement. There remains a lack of sensitive objective measures for edema in patients presenting with hand burn injury. Bioimpedance spectroscopy (BIS) is a measure of body composition that has been demonstrated by our group to be reliable for measuring whole body and limb edema during resuscitation and to be sensitive to edema changes within healing wounds. The aim of this study was to determine the reliability and validity of BIS as a measure of edema following hand burn injury specifically. One hundred patients presenting with burn injury including a portion of a hand were recruited to this trial. Repeated measures of the hand were recorded using a novel application of BIS and in parallel with water displacement volumetry (WDV). The results were analyzed using mixed-effects regressions. Paired repeated measures were obtained for 195 hands, using four electrode configurations. BIS demonstrated high reliability in measuring hand BIS-Intraclass Correlation Coefficient 0.995 to 0.999 (95% CI 0.992-1.000) and sensitivity-Minimum Detectable Difference 0.74 to 3.86 Ω (0.09-0.48 Ω/cm). A strong correlation was shown with WDV, Pearson's r = −0.831 to −0.798 (P < .001). BIS is a sensitive and reliable measure of edema following acute hand burn injury.