Success rate and complications: comparison of the dual-beveled atraucan spinal needles with the pencil-pointed whitacre spinal needles

INTRODUCTION: Atraucan spinal needles have dual bevels designed to make a smaller linear cut in the dura mater with the smaller and sharper bevel while dilating the opening with the other blunt bevel. In vitro, it has been shown to cause less CSF leakage than the 26 G Quincke or the 24 G Sprotte spinal needle. The goal of this study is to compare, in a prospective, randomized and double-blinded clinical trial, the success rate and complications in patients undergoing postpartum tubal ligation who received spinal anesthesia with either a 26 G Atraucan or 25 G Whitacre spinal needle. METHODS: 200 ASA I or II postpartum patients presenting for elective bilateral tubal ligation under spinal anesthesia were enrolled in the study after written consent and IRB approval. The patients were randomly assigned into either the Atraucan (AT, n=101), or the Whitacre (WH, n=99) group. In the AT group, the subarachnoid space was identified using a 26 G Atraucan needle (bevel turned paralleled to the longitudinal durai fibers). In the WH group, a 25 G Whitacre spinal needle was used. In both groups, the subarachnoid space was identified in the sitting position with midline durai puncture at L2-3 or L3-4 interspace. 75 milligrams of 5% lidocaine in 7.5% dextrose was then injected intrathecally. Age weight, height, gravity, parity, past history of headache(HA), smoking and alcohol history, number of attempts to successful spinal anesthesia, final cephalad level of anesthesia and intraoperative analgesic supplement were recorded for each group. An investigator, who was unaware of which spinal needle had been used, interviewed the patients each day while in the hospital and 7-10 days later at home, via telephone. Patients were questioned about the presence, severity and characteristics of headaches, backache, urinary retention and any other complains. A headache that was exacerbated by sitting up and relieved or improved significantly in supine position was considered to be a postdural puncture headache (PDPH). Chi-square test, Fisher's exact test and unpaired t-test were used for statistical analysis. A P value of less than 0.05 was considered significant. RESULTS: The two groups were demographically similar. 10 patients were excluded from the study due to loss in follow-up to complete the study data collection. The incidence of PDPH was 3.1% in AT group and 4.2% in WH group. All of the PDPH's were mild and resolved with either Advil or Tylenol without requiring epidural blood patch in any of the patients. The incidence of backache after 7 days postoperatively was 10.4% in AT group and 10.5% in WH group. All of the backache were mild and self-limiting. In terms of ease of spinal needle placement, AT group required an average of 1.6 attempts versus 1.7 attempts in WH group to achieve successful spinal anesthesia. The incidence of failed block (that is, spinal requiring significant IV supplement or conversion to general anesthesia) was 4.4 % in AT group and 3.5% in WH group. 98% of the patients in AT group and 95% in WH group were pleased with the spinal anesthesia and would not mind to have spinal anesthesia for future procedures. CONCLUSION: Obstetric and postpartum patients are at risk for PDPH. We found the complication rate (PDPH, backache) after spinal anesthesia, the success rate of spinal anesthesia and ease of spinal needle placement (number of attempts) were similar (without statistical significant difference) between the 26 G Atraucan and the 25 G Whitacre spinal needle. Furthermore, the PDPH and backache were all mild and did not require invasive treatment. This study showed that the Atraucan 26G spinal needle can be used without increasing complications or decreasing success rate and is a good alternative for the Whitacre 25 G spinal needle.