title: Risk Factors for Unintended Dural Puncture in Obstetric Patients: A Retrospective Cohort Study.
abstract: Unintended dural puncture (UDP) is one of the main risks of epidural analgesia, with a reported incidence of approximately 1.5% among the obstetric population. UDP is associated with maternal adverse outcomes, with the most frequent adverse outcome being postdural puncture headache (PDPH). Our retrospective cohort study objective was to identify demographic and obstetric risk factors that increase the risk of unintentional dural puncture as well as describing the obstetric outcome once a dural puncture has occurred.
  
  
  
  We retrospectively reviewed all cases of UDPs during attempted vaginal delivery between the years 2004 and 2013 in a single Israeli hospital. Each UDP case was matched with the 2 parturients who received epidural analgesia before and 2 parturients after performed by the same anesthesiologist (control group). Demographic, anesthetic, and obstetric variables were compared between the UDP and control groups.
  
  
  
  Out of 46,668 epidural procedures, 177 cases of UDPs were documented (0.4%). One hundred seven women (60.5%) developed PDPH, and 38 (35.5%) required an epidural blood patch. In multivariate logistic regression, the degree of cervical dilation in centimeters at the time of epidural insertion was associated with an increased rate of UDP (P < .001). Multiparity was associated with PDPH after UDP (P = .004). Women with UDP had longer length of hospital stay than those without UDP (P < .001).
  
  
  
  UDP, an uncommon complication, is associated with obstetric factors. Nevertheless, it does not seem to be associated with adverse obstetric outcomes except for prolonged duration of hospital stay.
authors.affiliation: From the Departments of *Anesthesia and †Obstetrics and Gynecology, Rabin Medical Center, Beilinson Hospital, Petach Tikvah, Israel; and ‡Department of Anesthesia, Shaare Zedek Medical Center, Jerusalem, Israel.
authors.forename: Sharon
authors.initials: S
authors.lastname: Orbach-Zinger
authors.forename: Eran
authors.initials: E
authors.lastname: Ashwal
authors.forename: Lilach
authors.initials: L
authors.lastname: Hazan
authors.forename: Danielle
authors.initials: D
authors.lastname: Bracco
authors.forename: Alex
authors.initials: A
authors.lastname: Ioscovich
authors.forename: Liran
authors.initials: L
authors.lastname: Hiersch
authors.forename: Andrey
authors.initials: A
authors.lastname: Khinchuck
authors.forename: Amir
authors.initials: A
authors.lastname: Aviram
authors.forename: Leonid A
authors.initials: LA
authors.lastname: Eidelman
mesh_terms: D000328:Adult; D015331:Cohort Studies; D036861:Delivery, Obstetric / Q000009:adverse effects* / Q000379:methods*; D005260:Female; D006801:Humans; D019300:Medical Errors / Q000009:adverse effects*; D051299:Post-Dural Puncture Headache / Q000175:diagnosis / Q000209:etiology; D011247:Pregnancy; D011677:Punctures / Q000009:adverse effects* / Q000379:methods; D012189:Retrospective Studies; D012307:Risk Factors