The effect of elective surgery on 3-methylhistidine excretion.

Elective surgical operation in normally nourished patients is associated with an increase of up to 40 per cent in the urinary excretion of 3-methylhistidine during the first three postoperative days. This increase was statistically significant (P less than 0.01) on the second and third postoperative days. This probably represents a minor degree of increased muscle proteolysis, principally due to the operative trauma. The possible effect of postoperative starvation requires further elucidation.