Background: This study was conducted in order to investigate the effect of patient expectation in the development of postural post-dural puncture headache (PPDPH).
Methods: 224 patients less than 55 years scheduled for minor non-obstetric surgery were randomised to receive single-injection spinal (SA) or epidural (EA) anaesthesia. A 27-g Quinke needle was used for SA and a 18-g Tuohy needle for EA. Patients, operating team and postoperative ward personnel were all blinded to the anaesthetic given and so was an independent observer responsible for follow-up after 5-7 days. The occurrence of headache, backache and other complaints was recorded. Headache was classified as PPDPH or non-PPDPH, and duration and intensity of the headache was registered. The quality of anaesthesia was directly evaluated by the surgeon using a VAS scale from 1 (excellent) to 10 (very poor) and indirectly by the supplemental use of opioid analgesia and general anaesthesia in the two groups.
Results: 212 patients, 103 SA and 109 EA, with a mean age of 36.7 years, could be fully evaluated. The groups were comparable with regards to age, sex and surgical procedure performed. Headache occurred in 44 patients postoperatively. PPDPH was diagnosed in 16 patients (15.5%) in the SA group and 2 (1.8%) in the EA group (P = 0.0014). Non-PPDPH occurred in 13 patients in each group. PPDPH had significantly greater mean intensity and duration than non-PPHPH. More patients in the EA group had postoperative backache (31.2%) than in the SA group (22.3%), but this difference was not statistically significant. More patients in the EA received general anaesthesia and opioid analgesia than in the SA group, and the surgeon's rating was on average 1.3 in the SA group compared to 2.5 in the EA group (P = 0.0003).
Conclusions: SA gave more headache but superior quality of surgical anaesthesia compared with EA. Dural puncture, and not expectation, is the major cause of PPDPH.