title: Finer gauge of cutting but not pencil-point needles correlate with lower incidence of post-dural puncture headache: a meta-regression analysis.
abstract: Post-dural puncture headache (PDPH) is a well-known neurological outcome caused by leakage of cerebrospinal fluid during neuraxial anesthesia. Studies aimed at assessing the efficacy of finer gauged spinal needles to reduce the incidence of PDPH have produced conflicting results. We have therefore examined the effect of the gauge of cutting needles and pencil-point needles, separately, on the incidence of PDPH.
  
  
  
  The PubMed, EMBASE and Google Scholar databases were searched for randomized studies which compared PDPH incidence in a head-to-head analysis of individual needle gauges of similar needle designs (cutting and pencil-point). A meta-regression analysis was performed taking into account various covariates, such as needle gauge and design, mean age of patient population, surgery type, percentage of males and females in study population and year of publication.
  
  
  
  Of the 22 studies (n = 5631) included in the analysis, 12 (n = 3148) and ten (n = 2483) compared different gauges of cutting needles and pencil-point needles, respectively. After adjusting for covariates, meta-regression analysis was performed for all studies that randomly compared individual needle gauges of similar needle design. Whereas the incidence of PDPH inversely correlated with gauge in cutting needles (β = -1.36 % per gauge, P = 0.037), no relationship was noted in pencil-point needles (β = -0.32 % per gauge, P = 0.114). Female gender was the only covariate that reached a statistically significant correlation with the incidence of PDPH in both models.
  
  
  
  A significant relationship between needle gauge and subsequent rate of PDPH was noted in cutting needles, but not pencil-point needles.
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins Hospital, 1800 Orleans Street, Sheikh Zayed Tower 3014C, Baltimore, MD, 21287, USA. azorrilla1@jhmi.edu.|Faculty of Health, Universidad Libre, Cali, Colombia. azorrilla1@jhmi.edu.
authors.forename: Andres
authors.identifier: 0000-0001-8140-8486
authors.initials: A
authors.lastname: Zorrilla-Vaca
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins Hospital, 1800 Orleans Street, Sheikh Zayed Tower 3014C, Baltimore, MD, 21287, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Healy
authors.affiliation: Faculty of Health, Universidad Libre, Cali, Colombia.
authors.forename: Carolina
authors.initials: C
authors.lastname: Zorrilla-Vaca
mesh_terms: D000775:Anesthesia, Spinal / Q000009:adverse effects* / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D015994:Incidence; D009339:Needles; D051299:Post-Dural Puncture Headache / Q000453:epidemiology* / Q000209:etiology; D013129:Spinal Puncture / Q000009:adverse effects
keywords: Patient safety; Post-dural puncture headache; Spinal anesthesia; Spinal needle