Aberrations in magnesium (Mg) metabolism have not been widely appreciated by the surgical community. Nevertheless, it is not uncommon for such abnormalities to occur during the postoperative period. We have encountered many situations of postoperative symptomatic hypomagnesemia and have wondered to what degree the surgical procedure contributed to the problem.
Undoubtedly, many cases of deranged Mg metabolism are not recognized because of failure to check serum levels of this cation. While the literature contains a number of accounts of postoperative increases and falls in serum Mg, little evidence of the effects of surgical trauma on such changes has been presented. The most often quoted articles by Haynes et al,1 Thoren,2 Beecher et al,3 and Gillette et al4 document a decrease in urinary Mg excretion with an associated rise in serum levels. Other authors have noted a transient postoperative hypomagnesemia in patients without severe shock.5-8