Preoperative glutamine loading does not prevent endotoxemia in cardiac surgery.
BACKGROUND
The presence of endotoxemia is relatively common in cardiac surgery patients and it may modify the metabolic and hemodynamic responses peri- and postoperatively. Impaired gut fuel metabolism may contribute to the disturbed function and deterioration of the intestinal mucosal barrier and the development of bacterial translocation and endotoxemia. Glutamine may protect the gut mucosal barrier during marginal or insufficient perfusion.


METHODS
We studied the effects of glutamine supplementation on endotoxemia and blood levels of tumor necrosis factor (TNF) during and after extracorporeal circulation (ECC) and the effects of endotoxemia on systemic and regional (splanchnic and leg) hemodynamics and metabolism after cardiac surgery. Nineteen elective coronary bypass patients were randomly assigned to receive preoperatively for 12 h either an infusion of glucose and a balanced amino acid solution (AA-group) or a solution containing 1/5 of total nitrogen as alanyl-glutamine (ALAGLN-group).


RESULTS
Glutamine and amino acid loading before ECC did not protect from peri- or postoperative endotoxemia. Endotoxemia was detected in 5 vs. 7 of patients during ECC and 6 vs. 5 of patients postoperatively in the ALAGLN-group vs. AA-group, respectively. More than half of the patients at every measurement had an increased level of TNF. There was no consistent difference between the arterial and hepatic vein endotoxin- or TNF-concentrations. Endotoxemia did not modify systemic or regional hemodynamics and metabolism after cardiac operation.


CONCLUSIONS
Glutamine did not prevent endotoxemia during or after cardiac surgery. An increased level of TNF was common and observed also in some patients without endotoxemia. Endotoxemia did not modify regional or whole-body metabolic patterns or hemodynamics.
Suojaranta-Ylinen
R
R
Department of Intensive Care, Kuopio University Hospital, Finland.
Ruokonen
E
E
Pulkki
K
K
Mertsola
J
J
Takala
J
J
D000596:Amino Acids / Q000008:administration & dosage; D001026:Coronary Artery Bypass / Q000009:adverse effects; D004151:Dipeptides / Q000008:administration & dosage; D004731:Endotoxins / Q000097:blood*; D005112:Extracorporeal Circulation; D005947:Glucose / Q000008:administration & dosage; D005973:Glutamine / Q000008:administration & dosage*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007262:Infusions, Intravenous; D007431:Intraoperative Complications / Q000517:prevention & control; D007866:Leg / Q000098:blood supply; D008875:Middle Aged; D010101:Oxygen Consumption; D011183:Postoperative Complications / Q000517:prevention & control; D011300:Preoperative Care; D013152:Splanchnic Circulation / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis; D014655:Vascular Resistance / Q000187:drug effects
D000596:Amino Acids; D004151:Dipeptides; D004731:Endotoxins; D014409:Tumor Necrosis Factor-alpha; D005973:Glutamine; D005947:Glucose; C054122:alanylglutamine