The comparison of the cerebrospinal fluid aspiration method and conventional popping method on dura puncture during spinal anesthesia with 27G Quincke needle

Of the 90 patients enrolled in the present study, two were excluded because the dural puncture failed and was recorded as incomplete. Therefore, 88 patients were included in the final analysis. There were no statistically significant differences in patient characteristics between the two groups (Table 1). In the aspiration group, the success rate of first attempt for dural puncture was 93.3% compared with 72.1% in the popping group (P = 0.019) (Figure 1). The success rate of first passage was 55.6% in the aspiration group and 34.9% in the popping group (P = 0.085) The withdrawal cases were 4 (8.9%) patients in the aspiration group and 13 (30.2%) in the popping group (P = 0.024). There was no difference in the number of needle passages between the two groups (P = 0.056). In the popping group, the number of attempts was significantly higher (P = 0.044). There was no difference in the successful attempt time for between the two groups. In the popping group, the total procedure time was significantly longer (P = 0.023). Data related to dural puncture between the two groups are summarised in Table 2. The distances from skin to anterior and posterior dura mater, and the depths for actual dura puncture in the two groups are presented in Table 3. The distances from skin to anterior or posterior dura mater in lumbar lateral X-ray films were comparable in both groups. The actual depths of dural puncture were deeper in the popping group than in the aspiration group (P = 0.019). There was no difference in the dose of hyperbaric bupivacaine and the level of spinal anaesthesia in both groups (P = 0.071 and P = 0.364). No complications occurred in either group.