Abstract: Analysis of Post-Operative Reoperation Timing and Risk Factors for Post-Operative Free Flap Compromise in Head and Neck Reconstruction: A National Retrospective Cohort

Abstract

INTRODUCTION: Unplanned reoperation, specifically for free flap compromise, following head and neck reconstruction can exert a significant toll on the healthcare system and its resources. The timing of the different indications for reoperation remains to be elucidated. Given that the National Surgical Quality Improvement Program (NSQIP) groups all causes of unplanned reoperations into a single variable, we aim to identify the rates and timing of various indications for reoperation and the independent predictors of head and neck free flap compromise. METHODS: A retrospective review of all patients who underwent head and neck free flap reconstruction for a malignant head and neck lesion was done in the ACS-NSQIP database 2012–2014. CPT codes 15756, 15757, and 15758 were identified to determine free flap reconstruction. Preoperative demographics, intraoperative variables and postoperative surgical morbidities were identified. Manual identification of ICD-9 codes allowed for determination of cause of reoperation. Subgroup analysis of mean time to reoperation was performed. Multivariate logistic regression was used to identify the independent predictors of unplanned free flap reoperation in the head and neck free flap population. An increased operative time was defined as >75%-tile (612 minutes). RESULTS: From 2012–2014, a total of 300 patients underwent head and neck free flaps. 62 patients (20.7 percent) underwent an unplanned reoperation. Most common reasons for unplanned reoperation were hematoma (19.4%), flap failure (19.4%) and a systematic vascular reason (17.7%). Mean time to reoperation was earliest in the hematoma cohort (4.33 ± 6.11 days) and flap failure cohort (4.92 ± 7.37 days). Latest time to reoperation was in the infection cohort (14.00 ± 4.85 days) and dehiscence cohort (13.50 ± 5.57 days). On multivariate logistic regression, independent risk factors for unplanned free flap reoperation (p < 0.05) included an ASA >3 [adjusted OR, 6.04 (95 percent CI, 1.40 to 26.07), adjusted p = 0.022] and an increased operative time in minutes [adjusted OR, 5.21 (95 percent CI, 1.54 to 17.64), adjusted p = 0.009]. CONCLUSION: National data indicates that complication rates are high in head and neck reconstruction for malignancy. Patients with independent risk factors for reoperation should be monitored more closely to reduce the severity of these complications. Development of a clinical risk calculator may help patient decision making by tailoring information on risk of complications.