OBJECTIVE
To assess the effects of abdominal operations on the production of cytokines as one of the mechanisms of postoperative immunosuppression.
DESIGN
Prospective study.
SETTING
University hospital, Belgium.
SUBJECTS
19 Selected patients who underwent operations for benign (n = 10) or malignant (n = 9) diseases.
INTERVENTIONS
Whole blood was collected in heparinised tubes before operation and on postoperative days 1, 2, 3, 5, 7, and 9. After 1/10 dilution in culture medium the whole blood cells were stimulated with 5 micrograms/ml phytohaemagglutinin and 25 micrograms/ml lipopolysaccharide, and incubated at 37 degrees C in 5% carbon dioxide. Concentrations of interleukin 1 (IL-1), tumour necrosis factor alpha (TNF alpha), and interleukin 6 (IL-6) were measured at 24 hours, and interferon-gamma and interleukin 2 (IL-2) were measured at 72 hours, with commercially available assays.
OUTCOME MEASURES
Production of the monokines IL-1, TNF alpha, and IL-6, and of the lymphokines IL-2 and interferon-gamma, postoperatively. The monokines were expressed as a percentage of the preoperative values/monocyte, and the lymphokines as a percentage of preoperative values/lymphocyte.
RESULTS
Production of IL-1 and TNF alpha, but not IL-6, decreased immediately after operation then returned to preoperative values. Production of IL-2 and interferon-gamma were significantly reduced immediately after operation, and that of interferon-gamma was still depressed on the ninth postoperative day.
CONCLUSION
Cytokine production is altered after abdominal operations. The production of interferon-gamma may be a more sensitive indicator of altered immune response and vulnerability to infections and tumour growth than concentrations of other cytokines.