Evaluation of dose-dependence of saddle block

Saddle block is a form of selective spinal anesthesia used during proctological, urological, and gynecological surgeries. A prospective randomized trial included 45 patients who had been operated on for hemorrhoids. According to the volume of an anesthetic injected into the subarachnoid space, the patients were randomized to 3 groups: 1) 15 patients received 1 ml (5 mg) of hyperbaric bupivacaine solution; 2) 15 had 1.5 ml (7.5 mg); 3) 15 had 2 ml (10 mg). The development of spinal saddle anesthesia was dose-dependent. Raising the dose of the hyperbaric solution of a local anesthetic resulted in an increase in the volume and duration of spinal anesthesia. Painful sensations appeared in 13.6% of the patients receiving its dose of 5 mg. The use of 10 mg of the anesthetic led to the development of the spinal anesthesia exceeding the volume of saddle block. The optimal dose for selective saddle anesthesia is 7.5 mg of hyperbaric bupivacaine solution.

spinal anesthesia, hyperbaric solution, dose-dependence, saddle block, sensory, motor block