VTE incidence after cesarean delivery

In the US, VTE is a leading cause of pregnancy-related morbidity and mortality, particularly after cesarean delivery; however, guidelines differ in the criteria suggested for VTE prophylaxis, possibly leading to notable differences in clinical practice

PATIENT POPULATION

• Overall, 1,235,149 cesarean delivery hospitalizations from 4,620 hospitals were included in the analysis (mean age = 29.8 years; mean length of stay for hospitalization = 3.5 days)

VTE PROPHYLAXIS

• There was a large variation in the percentage of patients meeting criteria for pharmacological prophylaxis:
  • ASH 2018 (0.2%)
  • ACOG 2011 (0.3%)
  • ACCP 2012 (16.2%)
  • RCOG 2015 (73.4%)

VTE INCIDENCE

• The overall incidence of VTE at 330 days after cesarean delivery was 2.1 per 1,000 hospitalizations (95% CI: 2.0, 2.2)
• The incidence of VTE (per 1,000 deliveries) in patients at elevated risk post cesarean delivery varied widely according to the guideline criteria employed:
  • RCOG 2015 (2.5%)
  • ACCP 2012 (5.6%)
  • ACOG 2011 (31.7%)
  • ASH 2018 (35.2%)
• All criteria identified low- and elevated-risk populations whose risk of VTE were statistically significantly different from each other, with varying relative risks:
  • ASH 2018 (RR = high risk/low risk: 17.3; 95% CI: 12.3, 22.2)
  • ACOG 2011 (RR: 15.7; 95% CI: 11.7, 19.9)
  • ACCP 2012 (RR: 3.9; 95% CI: 3.4, 4.3)
  • RCOG 2015 (RR: 2.2; 95% CI: 1.9, 2.5)

• Use of administrative (billing) data may have likely resulted in measurement errors in the recording of VTE incidences
• The use of VTE prophylaxis could not be observed in the available data and this could have impacted the incidence of VTE reported in this population
• The NRD is an inpatient-only dataset, hence any VTE identified/managed on an outpatient basis were excluded