Operating room-to-incision interval and neonatal outcome in emergency caesarean section: a retrospective 5-year cohort study

We conducted a 5-year retrospective cohort study on women undergoing caesarean section to investigate factors influencing the operating room-to-incision interval. Time-to-event analysis was performed for category-1 caesarean section using a Cox proportional hazards regression model. Covariates included: anaesthetic technique; body mass index; age; parity; time of delivery; and gestational age. Binary logistic regression was performed for 5-min Apgar score 7. There were 677 women who underwent category-1 caesarean section and who met the entry criteria. Unadjusted median (IQR [range]) operating room-to-incision intervals were: epidural top-up 11 (7-17 [0-87]) min; general anaesthesia 6 (4-11 [0-69]) min; spinal 13 (10-20 [0-83]) min; and combined spinal-epidural 24 (13-35 [0-75]) min. Cox regression showed general anaesthesia to be the most rapid method with a hazard ratio (95%CI) of 1.97 (1.60-2.44; p<0.0001), followed by epidural top-up (reference group), spinal anaesthesia 0.79 (0.65-0.96; p=0.02) and combined spinal-epidural 0.48 (0.35-0.67; p<0.0001). Underweight and overweight body mass indexes were associated with longer operating room-to-incision intervals. General anaesthesia was associated with fewer 5-min Apgar scores 7 with an odds ratio (95%CI) of 0.28 (0.11-0.68; p<0.01). There was no difference in neonatal outcomes between the first and fifth quintiles for operating room-to-incision intervals. General anaesthesia is associated with the most rapid operating room-to-incision interval for category-1 caesarean section, but is also associated with worse short term neonatal outcomes. Longer operating room-to-incision intervals were not associated with worse neonatal outcomes.