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.

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