Ventilatory Reserve and Level of Motor Block During High Spinal and Epidural Anesthesia

Abstract

Eighteen subjects were successively given spinal anesthesia with 50 to 75 mg. lidocaine, and epidural anesthesia with 15 to 35 ml of 2 per cent lidocaine containing 1:200,000 epinephrine. Mean levels of cutaneous analgesia (pin prick) and molor block (electromyography) were T 2.3 ±1.8 and T 5.1 ± 2.4, respectively, with spinal anesthesia, and T 3.6 ±1.2 and T 8.2 ±2.6 with epidural anesthesia. Mean inspiratory capacity fell 8 per cent with spinal anesthesia and 3 per cent with epidural anesthesia. Mean expiratory reserve volume fell 48 per cent with spinal anesthesia and 21 per cent with epidural anesthesia.