The measurement of axillary moisture for the assessment of dehydration among older patients: A pilot study

Abstract

Purpose: Dry axilla can sometimes be found among dehydrated older patients. In this study, we measured the axillary moisture and assessed it as possible marker for dehydration. Methods: Twenty-nine older patients admitted with acute medical conditions participated in this study. Dehydration was diagnosed by the calculated serum osmolality of greater than 295. mOsm/L. The moisture of axilla was measured by a skin moisture impedance meter which was applied at the center of axilla of patients. Results: 11 patients (7 males and 4 females) were diagnosed as dehydrated and 18 patients (10 males and 8 females) were diagnosed as non-dehydrated. The mean axillary moisture (33%) in the dehydrated group was significantly lower than that (42%) in the non-dehydrated group (p. <0.05). The axillary moisture ≥ 50% showed the sensitivity of 88%. The axillary moisture < 30% showed the specificity of 91%. Use of a single cutoff value of 40% moisture produced the sensitivity of 59% and the specificity of 9%. As for the physical signs, dry axilla had also moderate sensitivity and excellent specificity to detect dehydration. Conclusions: The measurement of the axillary moisture could help assess dehydration. Dehydration could be ruled out when the axillary moisture ≥ 50%, while it could be ruled-in when the axillary moisture is < 30%. © 2012 Elsevier Inc.