The importance of in-hospital mortality for patients requiring free tissue transfer for head and neck oncology.

Mortality is a rare but disastrous complication of microvascular head and neck reconstruction. The investigators attempt to identify the procedure-related mortality cases and analyse the causes of death. A retrospective analysis of 804 consecutive free flap procedures during a 19-year period was performed and fatal cases were identified (n=42 deaths). Multivariate logistic regression was employed to determine the association of in-hospital mortality with patient-related characteristics. The 30-day post-operative mortality rate was 1% (8 out of 804 patients), and the in-hospital mortality rate (post-operative deaths in-hospital before or after the 30th post-operative day without discharge) was 5.2% (42 out of 804 patients). Cancer recurrence and metastases related pneumonia were the most common causes of death (n=26, 62%), followed by cardiac, pulmonary, infectious and hepatic/renal aetiologies. Logistic regression analysis revealed that patients with stage IV disease and an operation time of >9h were significantly associated with post-operative mortality. Malignancy-related conditions were the most common causes of death following free flap transfer for head and neck reconstruction. For patients with stage IV head and neck cancer, this aggressive surgical approach should be cautiously justified due to its association with post-operative mortality. To shorten the operation time, experienced microsurgical operation teams are necessary.