Length of stay and return to theatre
There were 61 patients (17.7%) who returned to theatre during their inpatient stay. The mean length of stay was 16.2 days (SD = 10.7 d) and the median length of stay was 13 days, range (4 – 64 d). Operative time (per hour) was a significant predictor of length of stay (p < 0.001) with each additional hour of operative time being associated with an estimated one additional day in hospital (95%CI 0.67 – 1.33 days). This remained significant after adjusting for the effect of patient age, ASA statis, prior radiotherapy, defect type, reconstruction, and elective tracheostomy (p< 0.001).
There was a 17% increase in the odds of returning to theatre per additional hour of operative time (OR 1.17, 95%CI 1.08 – 1.26, p<0.001). Operations > 9 hours duration were associated with an 124% increase in the odds of returning to theatre compared to operations ≤ 9 hours duration (OR 2.24, 95%CI 1.27-3.94, p=0.005). After adjusting for the effect of patient age, ASA status, prior radiotherapy, defect type, and reconstruction, there was a 20% increase in odds of returning to theatre per additional hour of operative time (OR 1.20, 95%CI 1.09 – 1.32, p<0.001) and a 126% increase in patients undergoing operations > 9 hours duration compared to ≤ 9 hours duration (OR 2.26, 95%CI 1.24 – 4.12, p=0.008) (Table 5).