Background: Articaine and lidocaine are clinically very similar suggesting that articaine could be suitable for day-case spinal anaesthesia. A dose-response study with articaine in ambulatory spinal anaesthesia was therefore performed.
Methods: In this randomized double-blind study, 90 day-case surgery patients received spinal anaesthesia with 60 mg (A60), 84 mg (A84) or 108 mg (A108) of hyperbaric articaine hydrochloride. Sensory block was tested with pinprick and motor block on a modified Bromage scale. A structured interview was performed on the first and seventh postoperative days.
Results: Sensory block reached the T10 dermatome in a median (range) of 5 (5-10) and was maintained at this level for 70 (35-145), 70 (15-115) and 85 (20-115) min in the A60, A84 and A108 groups, respectively. Six patients in the A108 group, two in the A84 group and one in the A60 group had maximum spread of analgesia to T(1) or higher (NS). Patients in the A108 group needed more medication for hypotension (P=0.018), had more often nausea and vomiting (P=0.027), took oral fluids later (P=0.031) and both sensory block recovery [median (range)] [2.5 (2-4.5) h] (P=0.017) and motor block recovery [2 (1.3-4) h] (P=0.009) were delayed. No patients in the A108 group needed opioid intraoperatively while fentanyl was needed in 5 (17%) and 2 (7%) patients in the A60 and A84 groups, respectively. Discharge criteria were attained in approximately 4.5 h after articaine injection (NS) and no drug-related sequelae were observed.
Conclusions: Hyperbaric articaine 60 and 84 mg resulted in spinal anaesthesia allowing surgery of the lower extremities for about 1 h. Recovery was rapid. Use of 108 mg of articaine is not recommended because of frequent extensive cephalad spread of the block, accompanied by arterial hypotension and nausea.