• Anesthetic technique;
  • bupivacaine;
  • pharmacology;
  • spinal anesthesia

A prospective randomised study of the effect when the patient remained sitting for 2 (Group-2) or 60 min (Group-60) before being put in the supine horizontal position, was evaluated in 12 patients, aged 39–67 years and given a spinal anesthesia with 4 ml 0.5% bupivacaine in 8% glucose (hyperbaric). The maximal cephalad spread of analgesia was obtained after 12.5 min (median) in Group-2 and 75 min in Group-60 (P<0.01). The spread of sensory analgesia went to T-6 (Group-2) and L3 (Group-60) after 60 min (P<0.01). After 90 min the spread went to T6.5 in Group-60, the difference being statistically significant (P<0.001). Given as median and range the maximum cephalad spread in Group-2 was T6(T3-T10) and in Group-60 T6.5 (T2-T10).