[Subarachnoid anesthesia with pethidine]

Abstract

The authors present their experience about spinal anesthesia with pethidine as the sole medication. 713 patients whose mean age was 56.5 years received 1 mg . kg-1 of pethidine in 50 p. 100 aqueous solution administered by subarachnoid route. Indications were surgical procedures involving upper and lower abdomen, perineum and lower limbs. The set up of anesthesia is quite similar to those obtained with local anesthetics. Sensitivity disappears during the first three minutes in the area below the puncture site and in the following two or three minutes areflexia and paralysis is noted. The duration of the motor and sensory block is 90 to 120 minutes. Recovery appears to be in a reverse order. Spinal anaesthesia with pethidine exhibit the following characteristics: --sensory and motor blockade with minimal adverse reactions giving good and very good results in more than 90 per cent of cases, when involving perineum and lower limbs; --the most frequent adverse effect is a syndrome including hypotension, bradycardia and hypoxemia, appearing 20 to 30 minutes after injection, reversal is easily obtained by administration of pressure drugs and artificial ventilation. Neither delayed respiratory depression nor neurologic damage were noted; --a long lasting post-operative analgesia. In conclusion, this work demonstrates that: --1 mg . kg-1 of pethidine administered by subdural route realize a complete spinal anesthesia including motor, sensory and sympathetic blockade allowing surgical procedures in good conditions of security; --increasing the dosage of pethidine over 1 mg . kg-1 is not wise in order to avoid the occurrence of adverse side effects such as hypotension, bradycardia and bradypnaea; --this technic is only indicated for surgery in perineum and lower limbs.