The Role of Bioelectrical Impedance Analysis in Predicting Secondary Surgical Interventions for Lymphedema.

: Bioelectrical impedance analysis (BIA), known for its utility in monitoring fluid balance and lymphedema progression, is non-invasive and practical. However, circumferential tape measurements remain the gold standard for assessing limb volume changes, despite operator variability. This study investigated whether BIA could reliably assess the need for secondary surgical interventions in lymphedema patients. : We retrospectively analyzed lower extremity lymphedema patients who underwent multiple lymphaticovenous anastomoses on both legs from April 2017 to June 2023. This study involved 14 patients with a single surgery and 34 requiring additional surgeries. Logistic regression evaluated associations between the number of surgeries and valuables, including extracellular water-to-total body water (ECW/TBW) ratios measured via BIA, the sum of five-part circumferential values via tape measuring, age, and body mass index. Receiver operating characteristic (ROC) curve analysis calculated the area under the curve (AUC) for ECW/TBW and circumference values, analyzed separately for left and right legs. : ECW/TBW values were significantly associated with the need for a second surgery for both the right leg ( = 0.02, ROC-AUC = 0.86) and the left leg ( = 0.04, ROC-AUC = 0.86). In contrast, circumference measurements were not significant predictors for either the right leg ( = 0.46, ROC-AUC = 0.77) or the left leg ( = 0.60, ROC-AUC = 0.78). ECW/TBW demonstrated a higher AUC compared to circumference measurements, indicating its potential as a more sensitive tool for predicting the need for additional surgical interventions. : BIA may serve as a valuable tool for monitoring treatment outcomes and guiding secondary surgical planning. Larger studies are needed to validate its clinical utility.