Risk of venous thromboembolism in children after general surgery

Background/purpose: The purpose of the study was to determine absolute and relative rates of venous thromboembolism (VTE) following general surgical procedures in children compared to the general population.

Methods: We analyzed data from all patients under the age of 18years in the Clinical Practice Research Datalink, linked to Hospital Episode Statistics from England (2001-2011) undergoing a general surgical procedure and population controls. Crude rates of VTE and adjusted hazard ratios were calculated using Cox regression.

Results: We identified 15,637 children who had a surgical procedure with 161,594 controls. Six children undergoing surgery had a VTE diagnosed in the year after compared to five children in the population cohort. The overall rate of VTE following surgery was 0.4 per 1000 person years (pyrs) (95% confidence interval [CI] 0.15-0.88) compared to 0.04 per 1000 pyrs (95% CI 0.02-0.09) in the population cohort. This represented a 9 fold increase in risk compared to the population cohort (adjusted hazard ratio [HR] 8.80; 95% CI 2.59-29.94).

Conclusions: Children are at increased risk for VTE following general surgical procedures compared to the general population however the absolute risk is small and given this the benefits of thromboprophylaxis need to be balanced against the risk of complications following its use.