Identification of appropriate outcome indices in head and neck cancer and factors influencing them

Audit of early postoperative outcomes adjusted for patient case mix is still in its infancy in head and neck surgery. Nevertheless the role for audit of early postoperative outcomes is obvious. The primary outcome measure of this study was to identify factors that are associated with early mortality or morbidity after surgery for head and neck squamous cell carcinoma (HNSCC). The secondary outcome measure was to develop a pilot score that allows for risk-adjustment of outcome data to facilitate departmental audit. In this series the mortality rate was low (2.8%), in keeping with other published series. Complications, including those causing death, occurred after 38.1% of operations. Independent risk factors for mortality on logistic regression were shown to be previous HNSCC (P = 0.03), estimated blood loss (l) (P = 0.03), and extracapsular spread (P = 0.05). Age (P = 0.01), tracheostomy (P < 0.01), estimated blood loss (l) (P = 0.05), and duration of anaesthesia (P < 0.01) were independent predictors of complications. Models predicting for risk demonstrated good discrimination (area under the curve statistics) for mortality (0.86) and morbidity (0.81). These pilot scores need external validation and may herald a means of facilitating risk-adjustment in the audit of early outcomes, allowing meaningful comparison of surgeons and their units over time.