The anabolic effect of epidural blockade requires energy and substrate supply.
BACKGROUND
The authors examined the hypothesis that continuous thoracic epidural blockade with local anesthetic and opioid, in contrast to patient-controlled intravenous analgesia with morphine, stimulates postoperative whole body protein synthesis during combined provision of energy (4 mg x kg(-1) x min(-1) glucose) and amino acids (0.02 ml x kg(-1) x min(-1) Travasol 10%, equivalent to approximately 2.9 g x kg(-1) x day(-1)).


METHODS
Sixteen patients were randomly assigned to undergo a 6-h stable isotope infusion study (3 h fasted, 3 h feeding) on the second day after colorectal surgery performed with or without perioperative epidural blockade. Protein synthesis, breakdown and oxidation, glucose production, and clearance were measured by L-[1-(13)C]leucine and [6,6-(2)H(2) ]glucose.


RESULTS
Epidural blockade did not affect protein and glucose metabolism in the fasted state. Parenteral alimentation decreased endogenous protein breakdown and glucose production to the same extent in both groups. Administration of glucose and amino acids was associated with an increase in whole body protein synthesis that was modified by the type of analgesia, i.e., protein synthesis increased by 13% in the epidural group (from 93.3 +/- 16.6 to 104.5 +/- 11.1 micromol x kg(-1) x h(-1) ) and by 4% in the patient-controlled analgesia group (from 90.0 +/- 27.1 to 92.9 +/- 14.8 micromol x kg(-1) x h(-1);P = 0.054).


CONCLUSIONS
Epidural blockade accentuates the stimulating effect of parenteral alimentation on whole body protein synthesis.
D000465:Algorithms; D000596:Amino Acids / Q000097:blood / Q000378:metabolism*; D015360:Analgesia, Epidural / Q000009:adverse effects*; D016058:Analgesia, Patient-Controlled; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D000779:Anesthetics, Local / Q000009:adverse effects; D001786:Blood Glucose / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000601:surgery; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006728:Hormones / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D010288:Parenteral Nutrition; D014176:Protein Biosynthesis; D011659:Pulmonary Gas Exchange; D013268:Stimulation, Chemical
D000596:Amino Acids; D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D001786:Blood Glucose; D006728:Hormones; D009020:Morphine; D005947:Glucose