Anaesthetic considerations for major cancer resection and free flap reconstruction in oral cancer: a review

Abstract

This review outlines the key anaesthetic considerations for the intraoperative management of patients undergoing major oral cancer resection, with free flap reconstruction. Surgery is prolonged, and may include percutaneous endoscopic gastrostomy (PEG) tube insertion, tracheostomy formation, dental extractions, neck dissection, cancer resection, raising of the free flap, microvascular anastomosis, flap reperfusion, closure of the donor site, and reconstruction of the defect with the free flap. A clear airway management strategy is essential from the outset, and any markers of predicted difficulty should prompt consideration of an awake technique for tracheal intubation. Nasotracheal intubation is often performed to maximize surgical access. Many of these patients undergo elective tracheostomy and PEG formation at the time of surgery, though there is currently no international consensus on the suitability of undertaking these procedures in preference to a more conservative approach. Standard non-invasive anaesthetic monitoring should be employed, along with continuous invasive arterial blood pressure, core temperature and urine output monitoring. The choice of anaesthetic technique, volatile anaesthesia versus total intravenous anaesthesia (TIVA), remains at the discretion of the anaesthetist. Common free flap donor sites include radial forearm, anterolateral thigh, deep circumflex iliac artery (DCIA), fibula, and scapula. Regardless of the site selected, the principles of management to maximize flap success are the same—maintenance of normothermia, a hyperdynamic circulation with wide pulse pressure, and optimal haematocrit ratio. Once grafted, an implantable doppler probe can be sited to help monitor flap perfusion postoperatively. Other general intraoperative considerations include meticulous patient positioning, judicious fluid administration, venous thromboembolism prophylaxis, dexamethasone administration to reduce postoperative swelling, multimodal analgesia, and antimicrobial surgical prophylaxis. Good communication and effective multidisciplinary teamwork are essential in achieving the optimum patient outcomes from these complex surgical procedures.