Factors associated with poor intraoperative perfusion and postoperative complications in otolaryngological autologous tissue transfers: A single-centre retrospective observational study

The purpose of this study was to identify haemodynamic factors that are associated with tissue hypoperfusion in flap/graft surgical patients that might be modified to reduce perioperative morbidity. We conducted a single-centre, retrospective, observational study of 1355 patients undergoing head and neck flap reconstructions. Logistic regression and chi-square analyses were employed to identify factors which signal perioperative complications. Study endpoints included postoperative lactic acidosis, acute kidney injury (AKI) and early surgical flap revision surgery. Intraoperative data were collected as time-weighted averages of the haemodynamic variables, including pulse pressure variation (PPV), mean arterial pressure, and vasopressor doses. Cumulative volume was used for intravenous (IV) fluids. Relevant patient comorbidities were also included in the analysis. The most common complication was hyperlactataemia (22.9%), followed by AKI (14.1%) and take-back surgery (3.3%). No patient factors were significantly correlated with flap complications. Elevated max PPV was significantly associated with elevated lactate and AKI in univariate regression, but only AKI in the multivariate analysis (P = 0.003). Case duration was the only variable associated with take-back surgery in the multivariate regression (P = 0.007); it was also associated with lactic acidosis (P = 0.003). Neither IV fluid administration nor the use of vasopressors appeared to be associated with study outcomes in the multivariate analysis.