Restricted peri-operative fluid administration adjusted by serum lactate level improved outcome after major elective surgery for gastrointestinal malignancy.
BACKGROUND
Our objective was to compare the effect of a restricted intravenous fluid regimen adjusted by serum lactate level with a standard restricted regimen on complications after major elective surgery for gastrointestinal malignancy.


METHODS
This is a randomized, observer-blinded, single-center trial conducted across a time span of 13 months. A total of 299 patients were allocated to either a restricted intravenous fluid regimen with supplementary intravenous fluids given based on serum lactate level (group A) or a standard restricted regimen (group R). In group A, the serum lactate level was monitored closely postoperatively to maintain a normal pre-operative serum lactate level. Group R involved patients treated with a restricted fluid regimen in whom additional fluid and electrolytes were administered when deemed necessary based on the usual clinical criteria. The primary outcome measure was complications; the secondary measures were death and adverse effects.


RESULTS
Additional fluid supplementation was needed in some patients in both groups (group A [28%] vs group R [26%]). In group A, the time for additional fluid infusion occurred earlier in the postoperative period than group R. Patients in group A received their first supplementary fluid treatment within the first 12 h more commonly than those in group R (74% vs 37%, respectively; P < .004). The regimen adjusted by serum lactate decreased systemic postoperative complications in group A versus group R (10% vs 22%, respectively; P = .023) but not overall total complications (23% vs 33%, respectively; P = .090). In contrast, in patients who required additional fluid infusion, the difference in complications between the 2 groups was greater (overall complication, 45% vs 85%, respectively; P = .023; major complication, 16% vs 44%, respectively; P = .018; systemic complications, 19% vs 63%, respectively; P = .001). One patient died in group A and 4 died in group R (1% vs 4%, respectively; P = .206).


CONCLUSION
A fluid-restricted regimen after elective gastrointestinal operations for malignancy may lead to fluid insufficiency and low tissue perfusion in up to 28% of patients. Close monitoring of serum lactate levels with adjustment of intravenous fluid administration intraoperatively and in the early postoperative period may improve the early detection and correction of inadequate tissue perfusion, thereby decreasing the rate of complications.