Impact of cesarean versus vaginal delivery on the risk of postpartum acute kidney injury: A retrospective database controlled study in 116,876 parturients.

STUDY OBJECTIVE

The rate of cesarean delivery is increasing globally but the risk of perioperative organ injury associated with cesarean delivery is not well defined. The objective of this study was to determine the risk of postpartum acute kidney injury, a peripartum complication defined by an acute decrease in kidney function, associated with cesarean delivery compared to vaginal delivery.

SETTING

Population-based discharge database.

PATIENTS

The Optum Clinformatics® Data Mart was queried for parturients that underwent cesarean or vaginal delivery between January 2016 to January 2018. Using a propensity score model based on 27 antepartum characteristics, we generated a final matched cohort of 116,876 parturients.

INTERVENTION/EXPOSURE: Cesarean delivery as the mode of delivery.

MEASUREMENTS

The risk of acute kidney injury associated with each delivery mode and the effect of acute kidney injury on the length of hospital stay for parturients.

MAIN RESULTS

The matched cohort consisted of 116,876 deliveries, with 58,438 cases in each group. In the cesarean delivery group, the incidence of postpartum acute kidney injury was 24.5 vs. 7.9 per 10,000 deliveries in the vaginal delivery group (adjusted odds ratio = 3; 95% CI, 2.13-4.22; P < .001). The median of the length of hospital stay [interquartile range] was longer by 50% in parturients who developed postpartum acute kidney injury after vaginal delivery (3 [2-4] days vs. those who did not, 2 [2, 3] days; P < .001) and by 67% after cesarean delivery (5 [4-7] days vs. 3 [3, 4] days; P < .001).

CONCLUSIONS

Cesarean delivery is associated with a significantly increased risk of postpartum acute kidney injury as compared to vaginal delivery. The development of postpartum acute kidney injury is associated with prolonged length of hospital stay.