Peri‐operative effect of major gastrointestinal surgery on serum magnesium

Summary This study investigates the changes in serum magnesium levels after major gastrointestinal surgery and evaluates if Plasma‐Lyte 148 used as maintenance fluid influences these changes in the peri‐operative period. Thirty patients presenting for procedures ranging from anterior rectal resection to thoraco ‐abdominal cardio‐oesophagectomy were randomly allocated into two groups, one of which received compound sodium lactate solution as the maintenance crystalloid during the intra‐ and postoperative period, and the other Plasma‐Lyte 148, a magnesium‐containing crystalloid solution. Serum magnesium levels were measured pre‐operatively, in the immediate recovery period and 24 h postoperatively. The results showed a statistically significant (p < 0.05) reduction in the magnesium levels in both groups. The reduction was less marked in the Plasma‐Lyte group but this did not achieve statistical significance (p > 0.05) compared with the compound sodium lactate group.