Background and objectives. To evaluate the incidence of postdural puncture headache (PDPH) associated with continuous spinal anesthesia, 200 male patients (mean age 65 years) were randomly assigned to receive spinal anesthesia in one of three ways: group 1, 50 patients with an 18-gauge Tuohy-Schliff needle/20-gauge catheter combination; group 2, 50 patients with a newly developed 20-gauge Quincke point needle/24-gauge catheter combination; and group 3, 100 patients (control group, single injection spinal anesthesia) with a 22-gauge Quincke point needle.

Methods. Every patient was followed up for 7 days postoperatively.

Results. The incidence of PDPH was 6% with each continuous technique and 2% in the control group (difference not statistically significant). One group 1 patient who required an initial dose of 35 mg of tetracaine and 100 mg of lidocaine has a persistent, incomplete S4-5 sensory nerve deficit.

Conclusions. The incidence of PDPH associated with continuous spinal anesthesia is acceptable in appropriate clinical circumstances, but large initial doses of local anesthetic should not be administered.