Association Between Post-Dural Puncture Headache After Neuraxial Anesthesia in Childbirth and Intracranial Subdural Hematoma.

Importance: Women giving birth have high rates of dural puncture secondary to neuraxial anesthesia and are at high risk for a resulting headache. It appears to be unknown whether there is a significant association between post-dural puncture headache and subsequent intracranial subdural hematoma. Objective: To determine the association of post-dural puncture headache with postpartum intracranial subdural hematoma. Design, Setting, and Participants: This cohort study of patients used hospital discharges recorded in the US Agency for Healthcare Research and Quality National Readmission Database for women who experienced childbirth from January 2010 to December 2016. Patients were included if they had been admitted for childbirth, had 2 months of follow-up data, and did not receive a diagnostic lumbar puncture. Only the first delivery for a calendar year was studied. Data were analyzed from January 2018 to June 2019. Exposures: Women with post-dural puncture headache associated with neuraxial anesthesia in the 2-month postpartum period were identified using International Classification of Disease (Ninth Edition and Tenth Edition) codes and were compared with those without post-dural puncture headaches. Main Outcome and Measures: The primary outcome was intracranial subdural hematoma in the 2-month postpartum period. Secondary outcomes included in-hospital mortality and occurrence of neurosurgery. Results: A total of 26 469 771 patients with 26 498 194 deliveries were included. Exclusion of repeated deliveries (n = 28 423), deliveries without 2 months of follow-up data (n = 4 329 621), and deliveries with diagnostic lumbar puncture (n = 9334) resulted in a final cohort of 22 130 815 patients and deliveries. For the cohort, the mean (SD) age was 28.1 (6.0) years, and there were 68 374 post-dural puncture headaches, for an overall rate of 309 (95% CI, 302-316) per 100 000. There were 342 cases of subdural hematoma identified, indicating a rate of 1.5 (95% CI, 1.3-1.8) per 100 000 women. Of these, 100 cases were in women with post-dural puncture headache, indicating a rate of 147 (95% CI, 111-194) hematoma cases per 100 000 deliveries in this subgroup. Post-dural puncture headache had an unadjusted absolute risk increase of 145 (95% CI, 117-174) subdural hematoma cases per 100 000 deliveries. After adjusting for confounders, post-dural puncture headache had an odds ratio for subdural hematoma of 199 (95% CI, 126-317; P < .001) and an adjusted absolute risk increase of 130 (95% CI, 90-169; P < .001) per 100 000 deliveries. Conclusions and Relevance: The presence of presumed post-dural puncture headache after neuraxial anesthesia in childbirth, compared with no headache, was associated with a small but statistically significant absolute increase in the risk of being diagnosed with intracranial subdural hematoma. Further research is needed to establish if this association is causal for this rare outcome.