The effect of spinal needle design, size, and penetration angle on dural puncture cerebral spinal fluid loss.

Postdural puncture headache (PDPH) is a debilitating side effect of spinal anesthesia, the result of dural puncture and cerebrospinal fluid (CSF) leakage with an incidence of 3% to 75% in patient populations. Despite numerous in vitro and in viva studies that have identified predictors associated with PDPH, debate continues on the best technique to reduce CSF leak after dural puncture. The purpose of this in vitro study was to evaluate the relationship between spinal needle type (pencil tipped or cutting), needle size (22 or 25 gauge), and dura penetration angle from perpendicular (90 or 30 degrees), with the resulting CSF leak measured after dural puncture. Spinal needle designs continue to be studied and modified to reduce the incidence of PDPH in identified high-risk groups. For the study, 103 cadaver dura samples were punctured with randomly assigned needles at predetermined angles. The relationship between variables was analyzed. Our results found between needle tip designs a 5-fold increase in mean leak (Quincke > Whitacre) and between needle diameters (25 > 22 gauge), a 6-fold greater mean leakage. Puncture angle demonstrated no significant effect.