Safety of microvascular free tissue transfer reconstruction of the head and neck in the setting of chronic pharmacologic immunosuppression.

BACKGROUND: Patients on chronic pharmacologic immunosuppressive therapy are at increased risk of wound infection and complications after surgery. There is a paucity of data examining perioperative complications after microvascular free tissue transfer (MVFTT) reconstruction of the head and neck in this patient population. METHODS: Retrospective cohort study performed at two tertiary referral centers between August 2016 and May 2020. RESULTS: Nine hundred and seventy-nine patients underwent MVFTT during the study period; of these 47 (5%) patients were taking chronic immunosuppressive medications. The most common indications for immunosuppression were solid organ transplant and autoimmune disease. Fourteen (30%) patients had surgical complications within 30 days of surgery: 8 (17%) wound dehiscences, 6 (12%) hematomas, and 2 (4%) surgical site infections. There was one total and one partial flap failure with a 30-day reoperation rate of 4%. CONCLUSIONS: MVFTT of the head and neck appears to be safe in patients on chronic pharmacologic immunosuppression.

Free Flap Inset Techniques in Salvage Laryngopharyngectomy Repair: Impact on Fistula Formation and Function.

OBJECTIVE: To characterize pharyngocutaneous fistula (PCF) rates and functional outcomes following microvascular free tissue transfer (MVFTT) reconstruction of salvage total laryngectomy (STL) with a review of two different flap inset techniques and a review of the literature. METHODS: Retrospective review. RESULTS: Review of the literature revealed 887 patients who underwent STL MVFTT from 14 references. Ninety-six STL MVFTTs were performed by the authors, with 36 (38%) patients undergoing multilayer fascial underlay (MLFU) closure and 60 (62%) a standard single layer closure (SLC). One (3%) PCF occurred in the MLFU group compared to 12 (20%) in the SLC cohort (P = .03). Postoperative gastrostomy (G)-tube dependence was lower following MLFU closure compared to SLC (25% vs. 57%, P < .01), whereas pharyngoesophageal stricture (PES) (28% vs. 38%), tracheoesophageal puncture (TEP) placement (42% vs. 42%), and TEP usage (87% vs. 88%) did not significantly differ (P > .05). Compared to pooled rates from the literature, patients who underwent a MLFU MVFTT inset technique demonstrated significantly lower PCF incidence (3% vs. 23%, P < .01) without significant differences in PES (28% vs 23%, P = .55), G-tube dependence (25% vs. 23%, P = .25), or TEP placement (42% vs. 59%, P = .09). CONCLUSION: Despite MVFTT reconstruction after STL, G-tube dependence, PCF formation, and limitations of speaking rehabilitation (TEP) remain a significant issue. Modification of MVFTT inset may provide an opportunity to reduce PCF incidence without affecting other functional outcomes. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E875-E881, 2021.

Prognostic factors associated with achieving total oral diet following osteocutaneous microvascular free tissue transfer reconstruction of the oral cavity.

INTRODUCTION: Osteocutaneous microvascular free tissue transfer (OMFTT) is the current standard in reconstruction of large bony defects of the oral cavity. Although being able to swallow ranks as a top priority for patients undergoing OMFTT, factors associated with achieving an oral diet following surgery remain unclear. We sought to describe the rate of total oral diet achievement, and to identify possible pre-, intra-, and post-operative factors associated with achievement in patients undergoing OMFTT. METHODS: Retrospective review between January 1, 2010 and March 31, 2018 at two tertiary academic centers. RESULTS: 249 patients (67% male, mean age 58 years) met inclusion criteria, with a median follow up of 15 months. Overall, 142 (57%) of patients achieved a total PO diet post-operatively, with median time to achievement of 3.2 months. Multivariate analysis identified that lack of concurrent glossectomy (SHR 1.72 [1.09-2.70], p = 0.02), N0/1 disease (SHR 1.92 [1.16-3.13], p = 0.011), avoidance of post-operative fistula formation (SHR 1.96 [1.22-3.23], p = 0.005), pre-operative G-tube independence (SHR 3.33 [1.69-6.25], p < 0.001), and successful dental rehabilitation (SHR 2.08 [1.43-3.03], p < 0.001) are independently associated with total oral diet achievement. CONCLUSIONS: Bony resections not requiring glossectomy, limited nodal disease burden, pre-operative gastrostomy-independence, avoidance of post-operative fistula, and dental rehabilitation are independently associated with achievement of total oral diet following OMFTT reconstruction of the oral cavity. Counseling patients on associated risk factors is important in guiding post-treatment expectations. Minimization of post-operative fistula, and maximization of dental rehabilitation may significantly improve total oral diet achievement in this patient population.

Tissue engineering of a composite trachea construct using autologous rabbit chondrocytes.

The repair of large tracheal segmental defects remains an unsolved problem. The goal of this study is to apply tissue engineering principles for the fabrication of large segmental trachea replacements. Engineered tracheal replacements composed of autologous cells (neotracheas) were tested in a New Zealand White rabbit model. Neotracheas were formed in the rabbit neck by wrapping a silicone tube with consecutive layers of skin epithelium, platysma muscle, and an engineered cartilage sheet and allowing the construct to mature for 8-12 weeks. In total, 28 rabbits were implanted and the neotracheas assessed for tissue morphology. In 11 cases, neotracheas deemed sufficiently strong were used to repair segmental tracheal defects. Initially, the success rate of producing structurally sound neotracheas was impeded by physical disruption of the cartilage sheets during animal handling, but by the end of the study, 15 of 18 neotracheas (83.3%) were structurally sound. Of the 15 structurally sound neotracheas, 11 were used for segmental reconstruction and were left in place for up to 21 days. Histological examination showed the presence of variable amounts of viable epithelium, a vascularized platysma flap, and a layer of safranin O-positive cartilage along with evidence of endochondral ossification. Rabbits that had undergone segmental reconstruction showed good tracheal integration, had a viable epithelium with vascular support, and the cartilage was sufficiently strong to maintain a lumen when palpated. The results demonstrated that viable, trilayered, scaffold-free neotracheas could be constructed from autologous cells and could be integrated into native trachea to repair a segmental defect.