Favorable effects of epidural analgesia on hemodynamics, oxygenation and metabolic variables in the immediate post-anesthetic period.
Fourteen adult patients undergoing elective major abdominal surgery were divided into two groups. One group received epidural and general anesthesia (epidural group), and 20 ml of 0.125% bupivacaine and 2 mg of morphine were administered epidurally about 30 min before the end of the operation for post-anesthetic analgesia. The other group (control group) received general anesthesia alone with nitrous oxide, oxygen and enflurane. Flow-directed pulmonary arterial and radial arterial catheters were inserted preoperatively, and hemodynamic, respiratory, neuroendocrine and metabolic variables were measured serially. The data were compared during anesthesia and the immediate post-anesthetic recovery period. In the control group, the plasma epinephrine level in the post-anesthetic recovery period increased about four times over the anesthetic period. Oxygen consumption was increased and mixed venous oxygen saturation was decreased significantly. There was a close linear correlation between oxygen consumption (Y) and plasma epinephrine (X) level: Y = 285.7X + 90.5 (P < 0.01, r = 0.72). On the other hand, plasma epinephrine, oxygen consumption and mixed venous oxygen saturation did not change significantly in the epidural group in the post-anesthetic recovery period. There was also a close linear correlation between oxygen consumption (Y) and oxygen delivery (X): Y = 0.22X-32.0 (P < 0.01, r = 0.89). We conclude that the surgical stress and anesthetic reversal may seriously influence neuroendocrine responses and subsequently increase plasma epinephrine. Tissue oxygenation and metabolic imbalance may occur due to the rapid increase of epinephrine in the post-anesthetic recovery period. Epidural analgesia at this period may play a more important role and have a more favorable effect on the tissue metabolism.
Hosoda
R
R
Department of Anesthesiology, Branch Hospital, Nagoya University School of Medicine, Japan.
Hattori
M
M
Shimada
Y
Y
D000005:Abdomen / Q000601:surgery*; D000368:Aged; D015360:Analgesia, Epidural; D000762:Anesthesia Recovery Period; D000769:Anesthesia, Inhalation; D002045:Bupivacaine; D004737:Enflurane; D004837:Epinephrine / Q000097:blood; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009020:Morphine; D009609:Nitrous Oxide; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption / Q000187:drug effects*
D009020:Morphine; D004737:Enflurane; D009609:Nitrous Oxide; D010100:Oxygen; D002045:Bupivacaine; D004837:Epinephrine