Clinical Significance of Specific Gravity of Spinal Anaesthetic Agents Two Double-Blind Studies with Hyperbaric 5% Lidocaine

Abstract

In 2 double-blind studies 2 hyperbaric 5% lidocaine [LC] solutions containing glucose in concentrations of 75 mg/ml and 50 mg/ml, respectively, were compared. The onset and total onset time, spread, intensity, duration of analgesia and motor block were studied. The spinal anesthesia was given with the patient either sitting or in the lateral recumbent position. A tendency to a longer duration of anesthesia near dermatomes Th X-L II and L IV-L V was noted in the group of patients in the sitting position and receiving LC with a lower glucose concentration. Otherwise there were no differences between the 2 LC solutions. The results show that the glucose concentration can be reduced from 75 to 50 mg/ml in heavy LC without any clinical disadvantage. This means a more isotonic solution in relation to the CSF, resulting in milder osmotic effects on interspinal structures.