Spinal procaine with and without epinephrine and its relation to transient radicular irritation

Abstract

Purpose: To document the clinical characteristics of procaine with or without the addition of epinephrine. Methods: In this randomized, prospective, double blind study, 62 patients received spinal anesthesia with 100 mg procaine and either 0.3 mg epinephrine (EPI group) or 0.3 ml NaCl 0.9% (SALINE group). Sensory anesthesia to needle prick was evaluated q 1 min for 10 min, q 3 min for 33 min and q 5 min until regression to L4. Motor block was assessed with the Bromage scale. Patients were questioned, by telephone, for transient radicular irritation (TRI) 48 hr later. Results: Time to reach highest sensory level and number of segments blocked showed no difference. Mean time for regression of the sensory level to T10 was longer in EPI (83 ± 23 vs 66 ± 20 min, P < 0.01). Time to recuperate to full flexion of knees and feet (Bromage 4) was longer in EPI (126 ± 37 vs 100 ± 30 min, P < 0.01). Patients in EPI received more ephedrine. Eighteen patients had nausea (15 EPI/3 SALINE, P < 0.0015). One patient had TRI, incidence: 1.67%, 95% Cl (<1%-9%). Conclusion: Spinal procaine is appropriate for surgery of short duration. Epinephrine prolongs sensory and motor blocks by 25%. However, it is associated with a high incidence of nausea.