Effect of Small Versus Large Epidural Needles on Postdural Puncture Headache Study

Randomized Controlled Trial Examining the Effect of Small Versus Large Tuohy-type Epidural Needles on the Incidence and Severity of Postdural Puncture Headache

The purpose of this study is to determine the effect of 19g versus =>18g traditional Tuohy-type epidural needles on the incidence and severity of postdural puncture headache (PDPH).

A headache is the most significant complication of dural puncture during epidural placement. This complication leads to longer hospital stays and many repeated visits to hospital for management. Women suffering from severe postdural puncture headache (PDPH) are often bedridden and unable to care for themselves or their babies.The efficacy of epidural blood patch as a "gold standard" therapy is over-estimated by the earlier, poor quality studies. The prevalence of dural puncture during epidural anesthesia using current techniques ranges from 0.03 to 6% in the literature. Of these patients, 70 to 80% will suffer from moderate to severe PDPH. Avoidance of dural puncture is always the goal. However, complete avoidance is unlikely using current techniques of needle placement. This study proposes another method of prevention (i.e., reducing the gauge of the epidural needles if it is shown to be suitable for continuous infusion in adults). Most of the risk factors for developing PDPH cannot be changed (e.g., younger age, female sex, low body mass index, history of migraines). However, epidural needle gauge is a modifiable risk factor. Evidence suggests that the use of smaller gauge epidural needles, like spinal needles, have the potential to reduce the incidence and severity of PDPH.

Parturient, Obstetrics, Pregnancy, Labour, Labor, Headache, Epidural, Analgesia, Anesthesia, Anaesthesia

Health Canada Health Protection Branch (HPB) Licence # 6832, Smith's Medical epidural mini-kits 100/391/190

Patients in the experimental group will receive a 23g 90cm adult length epidural catheter placed via a 19g Tuohy epidural needle (SIMS Portex, Hythe, UK). The 19g Tuohy needle is a standard 3½ inch length.

Patients in the control arm will receive a traditional large gauge (16g, 17g or 18g Tuohy or Hustead) epidural needle and a traditional epidural catheter. Two control needles and two control catheters will be designated apriori by each institution for use in the study.

PDPH characteristics (quality, distribution, postural versus non-postural nature, associated symptoms)

Pain and pain relief (first and second stage labor analgesia following epidural placement and overall pain relief) as rated by the patient, compared between groups

Number and timing of epidural blood patches received, total number of epidural blood patches received until symptom resolution

Risk of delayed block failure for continuous labour analgesia in patients receiving a 19g Tuohy epidural needle and 23g catheter

Risk of requiring use of an alternative method of anesthesia for operative delivery in patients receiving successful epidural initiation with a 19g Tuohy epidural needle and a 23g catheter

Anesthesiologist satisfaction with the 19g Tuohy epidural needle and 23g catheter compared with traditional Tuohy type epidural needles and traditional catheters

Inclusion Criteria: American Society of Anesthesiologists status 1 to 2 Must have provided written informed consent = or < 6cm cervical dilation Fetus 37 to 42 weeks gestation Must be able to read and write English well enough to provide written informed consent Exclusion Criteria: BMI = or > 40 Multiple gestation pregnancy Known contraindications to use of epidural analgesia Pregnancy-induced hypertension Investigator concern for maternal or neonatal welfare Receipt of spinal or epidural anesthesia within 14 days of labour epidural request Women with chronic headaches (defined as headaches that occur 15 or more days per month for more than 3 months) Already participated in study History of narcotic abuse

Angle PJ, Hussain K, Morgan A, Halpern SH, Van der Vyver M, Yee J, Kiss A. High quality labour analgesia using small gauge epidural needles and catheters. Can J Anaesth. 2006 Mar;53(3):263-7. doi: 10.1007/BF03022213.