Skeletal Muscle Index's Impact on Discharge Disposition After Head and Neck Cancer Free Flap Reconstruction.

[OBJECTIVE] To determine the role of skeletal muscle index (SMI) in the assessment of frailty and determination of discharge to post-acute care facilities (PACF) after head and neck cancer free flap reconstruction (HNCFFR).

[STUDY DESIGN] Retrospective cohort.

[SETTING] Single-institution, academic tertiary referral center.

[METHODS] Adult patients undergoing HNCFFR from 2014 to 2019 with preoperative abdominal computed tomography imaging were retrospectively analyzed. Patient demographics, 5-factor modified frailty index (5-mFI), body mass index (BMI), SMI at the third lumbar vertebra, oncologic history, perioperative data, and Clavien-Dindo (CD) complications were collected. Binary logistic regression was used to identify independent predictors of discharge disposition.

[RESULTS] The cohort consisted of 206 patients, 62 (30.1%) of whom were discharged to PACF. Patients discharged to PACF were of older age (65.4 vs 57.1 years, < .0001) and had a lower SMI (38.8 vs 46.8 cm/m, < .0001), higher 5-mFI (≥3; 25.8% vs 4.2%, < .0001), and greater incidence of stage IV (80.6% vs 64.1%, = .0211) aerodigestive cancer (80.6% vs 66.7%, = .0462). Patients discharged to PACF experienced more blood transfusions (74.2% vs 35.4%, < .0001), major postoperative complications (CD ≥3, 40.3% vs 12.9%, < .0001), and delirium (33.9% vs 4.2%, < .0001). After adjusting for pre- and postoperative factors, multivariate binary logistic regression identified age ( = .0255), 5-mFI ( < .0042), SMI ( = .0199), stage IV cancer ( = .0250), aerodigestive tumor ( = .0366), delirium ( < .0001), and perioperative blood transfusion ( = .0144) as independent predictors of discharge to PACF.

[CONCLUSIONS] SMI and 5-mFI are independently associated with discharge to PACF after HNCFFR and should be considered in preoperative planning and assessment of frailty.