Role of glutamine administration on T-cell derived inflammatory response after cardiopulmonary bypass.
OBJECTIVE
Cardiac surgery provokes an inflammatory response for which the endothelium, the myocardium, and monocytes/macrophages are primarily responsible. T cells are altered in a different way whereby the pro-inflammatory pathway is suppressed. From the results of experimental studies it was concluded that glutamine (Gln) enhances the production of T-cell cytokines in conditions of Gln deprivation. The aim of this clinical study was to evaluate the role of a perioperative Gln infusion on intracellular inflammatory T-cell cytokine expression in patients undergoing elective cardiac surgery and to evaluate the effects on systemic inflammation, organ dysfunction and ICU length of stay.


METHODS
In this prospective, randomized, double-blind study, we included 78 patients (age level older than 70 years, ejection fraction less than 40%, or mitral valve replacement) undergoing elective cardiosurgery with cardiopulmonary bypass. We randomly assigned each subject to receive an infusion with either Gln (0.5 g/kg/day, group A) or an isonitrogenous, isocaloric, isovolemic nutritional solution (group B) or physiological NaCl 0.9% (group C, to eliminate an unspecific nutritional effect). We started the infusion after the induction of anesthesia with 1000 ml/24 h and maintained this state for 3 days.


RESULTS
On the first postoperative day plasma Gln levels in group A were significantly increased (958 +/- 331 microM) compared to group B (527 +/- 105 microM) and group C (489 +/- 104 microM), and remained higher until the third postoperative day. At the beginning and after surgery intracellular interleukin (IL)-1, IL-6, IL-8, and tumor necrosis factor-alpha levels in T cells showed no differences between the groups. Also, no differences could be observed with regard to C-reactive protein, SOFA score, heart and circulation support, postoperative ventilation time, and ICU length of stay.


CONCLUSIONS
The elevation of Gln plasma levels as a result of 0.5 g/kg/day perioperative Gln infusion has no influence on the T-cell derived inflammatory response, indicating a sufficient supply of Gln. A Gln supplementation in cardiac surgery patients without a clear Gln deficiency seems not to affect the intracellular inflammatory T-cell cytokine expression.
Department of Anesthesiology, Intensive Care Medicine, Pain Therapy, University Hospital Giessen and Marburg GmbH, Giessen, Germany. joerg.engel@lahn-dill-kliniken.de
J M
JM
Engel
S
S
Pitz
J
J
Mühling
T
T
Menges
F
F
Martens
M
M
Kwapisz
G
G
Hempelmann
D000368:Aged; D002097:C-Reactive Protein / Q000378:metabolism; D002315:Cardiopulmonary Bypass; D016207:Cytokines / Q000096:biosynthesis* / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D005973:Glutamine / Q000008:administration & dosage* / Q000097:blood*; D006331:Heart Diseases / Q000097:blood / Q000276:immunology / Q000601:surgery; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000517:prevention & control*; D007262:Infusions, Intravenous; D007902:Length of Stay; D008297:Male; D019990:Perioperative Care / Q000379:methods; D011182:Postoperative Care; D011183:Postoperative Complications / Q000517:prevention & control; D011446:Prospective Studies; D018417:Th1 Cells / Q000187:drug effects / Q000276:immunology; D018418:Th2 Cells / Q000187:drug effects / Q000276:immunology
D016207:Cytokines; D005973:Glutamine; D002097:C-Reactive Protein