///2017 Abstract Details
2017 Abstract Details2019-08-02T15:54:53-06:00

Do Ethnicity and Body Mass Index Make a Difference in the Incidence of Unintentional Dural Puncture and Epidural Blood Patch?: A Retrospective Study

Abstract Number: SAT-52
Abstract Type: Original Research

Jie Zhou MD, MS, MBA1 ; Minxian Liang MD2; Xixi Zhou MS3; Tianyue Mi MS4

Introduction: Unintentional dural puncture (UDP) occurs in approximately 1% of parturients who receive labor analgesia. While body mass index (BMI) varies among people with difference ethnicity backgrounds, there has been no study with focus on the relationship of incidence of UDP and ethnicity background. We hypothesize that 1) the incidences of UDP and EBP differ across ethnicity; 2) BMI plays a role in the occurrence of UDP and EBP.

Methods: We identified 67,295 epidurals and combined-spinal-epidural procedures performed from January 1, 2005 to December 31, 2016. Chart review of all the cases with obstetric anesthesia complication follow-up was conducted. The primary outcome was the incidence of UDP and subsequent EBP. The association between BMI, ethnicity, UDP and EBP was analyzed by using modified Poisson regression. Given the limitation of electronic medical record (EMR) system and time constrain, ethnicity ratio composite of the population was estimated using a sample size of 8,909, of which the ethnicity data were extracted from EMR.

Results: UDP was identified in 308 parturients. The overall incidence of UDP was 0.46%. The incidence of UDP in each ethnicity was 0.06% (Asian), 0.07% (Black), 0.07% (Hispanic) and 0.26% (White/Caucasian). After adjusting for BMI, the Asian population had a 1.62 times greater risk for UDP than that of the White/Caucasian population [Risk ratio (95% CI) 1.62 (1.15 to 2.28), p-value=0.006]. However, there is no difference of the incidence of UDP in other ethnicities compared to the White/Caucasian population. BMI is significantly associated with the incidence of UDP [Risk ratio (95% CI) 1.07 (1.05 to 1.08), p-value<0.001]. Meanwhile, we analyzed the relationship between parturients’ BMI and the incidence of UDP and EBP after adjustment for ethnicity, and no significant association was identified.

Discussion: Our data demonstrated that Asian population has a higher risk of UDP than other ethnicities when compared to White/Caucasian population. Possible explanations include the thinner subcutaneous tissue and ligament in Asian parturients’ compared to that of other ethnicities, provider’s technical skill and experience. Increased BMI also contributes to an increased UDP rate. However, we did not see an association between BMI and the incidence of EBP, of which the literature has shown strong


1. Hollister N, et al. IJOA 2012;21(3):236-41.

2. Peralta F, et al. Anesth & Analg 2015;21(2):451-6.

SOAP 2017