Isobaric tetracaine spinal anesthesia and the lithotomy position.
The extent and pattern of anesthesia produced by hyperbaric and by isobaric 0.5% tetracaine spinal anesthesia were compared in this blind-observer, randomized study of 103 spinal anesthetics performed in 98 patients having genitourinary surgery in the lithotomy position. Pinprick stimulation showed no significant differences in maximum segmental sensory levels, times to maximum level, or duration of anesthesia for isobaric as compared to hyperbaric tetracaine. No parameters were significantly altered by barbotage of isobaric tetracaine solutions. With injections given to patients in the sitting position and with patients subsequently maintained in a horizontal lithotomy position before being put in the lithotomy position, the addition of dextrose to tetracaine solutions injected at room temperature into the subarachnoid space does not significantly alter the cephalad spread of spinal anesthesia.
D000328:Adult; D000368:Aged; D000775:Anesthesia, Spinal / Q000379:methods; D005260:Female; D005947:Glucose; D006801:Humans; D008297:Male; D008875:Middle Aged; D011187:Posture; D011897:Random Allocation; D013346:Subarachnoid Space; D013748:Tetracaine / Q000008:administration & dosage*; D014566:Urogenital System / Q000601:surgery*
D013748:Tetracaine; D005947:Glucose