Risk factors for prolonged postoperative mechanical ventilation following head and neck microvascular free flap reconstruction and its association with patient outcomes

Prolonged mechanical ventilation is associated with increased mortality rates and longer hospital and intensive care unit (ICU) stays. The literature identifying risk factors for prolonged postoperative mechanical ventilation in patients undergoing head and neck microvascular reconstruction is limited. The aim of this retrospective cohort study was to identify risk factors for prolonged mechanical ventilation. The primary outcome was the duration of ventilation, categorized as early extubation (≤48 h) and prolonged ventilation (>48 h). Secondary outcomes were return to the operating room, the patient's estimated risk for postoperative respiratory failure, length of stay (LOS), and need for post-discharge rehabilitation. P-values <0.05 were considered statistically significant. Overall,144 patients were included: 51 (35.4%) with early extubation and 93 (64.6%) with prolonged ventilation; the mean duration of ventilation was 36.2 h vs 249 h, respectively. The prolonged ventilation group had an increased rate of return to the operating room, LOS (ICU and total), and rate of discharge to rehabilitation facilities (all P < 0.001). Tongue reconstructions had the longest mean hospital stay (P = 0.003). Current smoking (P = 0.011) and ASA score 3 (P = 0.025) and 4 (P = 0.006) were significant risk factors for prolonged mechanical ventilation.