Risk Factors and Complications Associated with Early Oral Intake in Patients Undergoing Microvascular Free Flap Reconstruction of the Oral Cavity: A Single-institution, Retrospective Study

Abstract

PurposeData on early oral intake (PO) after free flap reconstruction of the oral cavity have been limited. Recent studies have shown that resumption of PO after free flap reconstruction does not lead to increased morbidity and has resulted in decreased hospital stay.1,2 The objective of the study is to assess postoperative complications associated with early PO after free flap reconstruction of the oral cavity and to define clinical predictors for early PO. Materials and methodsA retrospective study was designed and implemented to capture all patients who were treated from 2014 to 2019 at a tertiary hospital and academic medical center. Inclusion criteria included oral cavity defects as a result of malignant or benign disease, trauma, osteoradionecrosis, and medication-related osteonecrosis that required a vascularized free flap reconstruction. Exclusion criteria included unresectable tumors, pharyngeal or laryngeal defects, and facial defects with minimal intraoral involvement (i.e., skin cancer). Clinical and surgical variables were collected and analyzed. The treatment group received PO within 4 days postoperatively. The control group had PO after 4 days postoperatively. The primary outcome was an early complication during the primary hospitalization. Secondary outcomes included late complications and length of stay (LOS). Student's T-test and Chi-square test were used to compare continuous and categorical variables, respectively. In cases where an unequal distribution or a small sample size is present, Mann-Whitney U or Fisher's Exact test was performed. Study variables that were statistically associated with the primary outcome in the bivariate analysis were selected as independent variables for logistic regression analysis. Multivariable logistic regression analysis was used to control for demographic and clinical variables that were statistically significant in the simple logistic regression analysis. Odds ratios (ORs) with 95% confidence intervals (CIs) were recorded and interpreted for the regression analysis. For all tests, P values of < .05 were statistically significant. ResultsA total of 457 free flap reconstructions were screened for eligibility. The study sample composed of 423 reconstructions in 164 females and 259 males with the mean age of 59 (range 14-88 years) and mean follow-up duration of 25 months. Sixteen percent of the sample had prior radiotherapy or chemoradiotherapy, and 70% were treated for malignant disease. The majority underwent a tracheostomy (81.6%) and unilateral neck dissection (75.4%). Half had a gastrostomy tube (G-tube) during their hospitalization. The flap success rate was 98%. Patients in the treatment group were less likely to have a tracheostomy, bilateral neck dissection, and g-tube compared to the control group (P < .01) (Table 1). Defect volumes were significantly smaller in the treatment group compared to the control group (P < .01) with buccal and maxillary defects being more common in the treatment group (P < .01). Early PO was associated with decreased LOS (P < .01) and comparable complications (P > .10) in the treatment group compared to the control group (Table 2). Patients in the control group had a higher incidence of neck infection and salivary leak during the primary hospitalization compared to the treatment group. Late complications such as exposed hardware or bone, neck infection, and orocutaneous fistula were more frequent in the control group compared to the treatment group (Table 3). Multivariable regression analysis showed that tracheostomy and defect volume were significant predictors for early PO (P < .01). ConclusionEarly PO after free flap reconstruction of the oral cavity decreases LOS and does not lead to worse outcomes with regards to early and late complications. However, factors such as defect location, defect volume, and tracheostomy may increase the risk for complications and can help guide surgeons in deciding the optimal timing for postoperative PO.