Evaluation of modified frailty index for predicting post-operative outcomes after lower-extremity free-flap reconstruction.

Abstract

Risk stratification for complex procedures such as microsurgical reconstruction of the lower extremities is an important part of preoperative planning and counseling. The aim of this study was to determine the effectiveness of the modified five-item frailty index (5-mFI) score, a validated tool for assessing risk in surgical patients, in predicting postoperative complications after lower extremity (LE) free flap reconstruction. A retrospective review of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was conducted from 2010 to 2020 on patients who underwent LE free-flap reconstruction. 5-mFI scores were calculated and patients were categorized as 5-mFI ≥2 or <2. The primary endpoint was the presence of 30-day overall complications. The secondary endpoints included 30-day readmission, need for reoperation, and need to discharge to a care facility. Comparisons were made using one-way analysis of variances, Pearson's chi-squared test, or Fisher's extract test. Multivariable logistic regression models were performed for sex, age, BMI, smoker status, operative time, and ASA classification. Total of 294 (61.6% males) patients were identified. Univariate analysis showed 5-mFI ≥2 had higher rates of overall complications (p = .043) and hematologic complications (p = .033). In this population, there were also higher rates of reoperation (p = .003) and discharge to care facility (p < .001). Multivariable regression models further substantiated that 5-mFI ≥2 was independently associated with increased overall complications [2.46, CI: 1.10-5.59, p = .031], hematologic complications [2.55, 1.02-6.35, p = .046], reoperation [4.55, 1.54-13.3, p = .006], and discharge to facility [2.86, 1.27-6.45, p = .011]. There is a strong association of 5-mFI ≥2 with adverse post-operative outcomes in male patients undergoing LE free-flap reconstruction. This can be a valuable adjunct in the counsel of patients for whom lower extremity salvage is feasible.