title: Responses to dural puncture during institution of combined spinal-epidural analgesia: a comparison of 27 gauge pencil-point and 27 gauge cutting-edge needles.
abstract: Pencil-point spinal needles are popular for combined spinal-epidural analgesia because they cause less dural puncture headache than cutting-edge spinal needles. However many parturients move, grimace, vocalise or experience paraesthesia or dysaesthesia during dural puncture when performing 'needle through needle' combined spinal-epidural analgesia. We compared dural puncture responses induced by pencil-point and cutting-edge needles (both 27 gauge). With institutional approval, 115 parturients presenting for elective caesarean section or labour analgesia were audited. After lignocaine infiltration, a Tuohy-type needle was inserted to loss of resistance to saline at a mid-lumbar interspace, and either a 27 gauge cutting-edge or 27 gauge pencil-point needle was inserted 'needle through needle' through the dura. During dural penetration, the occurrence of patient movement, grimacing or vocalisation was noted by a blinded observer, as was the patient's response to the question "Did you feel that?" asked by the anaesthetist. The audit comprised two similar groups of patients (caesarean section, n=30; labour analgesia, n=85). In both groups, grimacing and movement during thecal penetration occurred more frequently with pencil-point needles (P < 0.05 and P < 0.025, respectively). Pooled data analysis revealed that pencil-point and cutting-edge needles induced grimacing and movement in 17 (22%) and 2 (5%), spontaneous vocalisation in 4 (5%) and 1 (3%) and was perceived by 13 (17%) and 3 (8%) parturients (P < 0.025, P=NS, P=NS), respectively. Overall, 34 and 6 objective and subjective patient responses (P < 0.005) occurred when inserting these needles, respectively. Dural puncture by a 27 gauge pencil-point needle inserted 'needle through needle' when instituting combined spinal-epidural analgesia induces more iatrogenic responses than a 27 gauge cutting-edge needle.
authors.affiliation: Department of Anesthesiology, University of Texas, Houston, Texas, United States of America. antonvdb2000@yahoo.com
authors.forename: A A
authors.initials: AA
authors.lastname: van den Berg
authors.forename: S
authors.initials: S
authors.lastname: Ghatge
authors.forename: G
authors.initials: G
authors.lastname: Armendariz
authors.forename: D
authors.initials: D
authors.lastname: Cornelius
authors.forename: S
authors.initials: S
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D015360:Analgesia, Epidural / Q000379:methods; D016362:Analgesia, Obstetrical / Q000379:methods*; D000775:Anesthesia, Spinal / Q000379:methods; D002585:Cesarean Section; D005260:Female; D006801:Humans; D007743:Labor, Obstetric; D009339:Needles; D011247:Pregnancy; D011446:Prospective Studies; D013129:Spinal Puncture / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D055815:Young Adult