Changes of white blood cells, immunosuppressive acidic protein, and interleukin-2 receptor after open heart surgery.

There are a lot of immunological changes after major surgery, especially in open heart surgery when blood flows through a cardiopulmonary bypass system. We monitored leukocyte count, lymphocyte subpopulation count, soluble IL- 2 receptor (sIL-2r) and serum IL-2 levels, and an immunosuppressive acidic protein (IAP) level before and on the 1st, 7th, and 14th day after open heart surgery. It was noted that there were significant increases of total leukocyte and granulocyte counts for more than two weeks. But total lymphocyte, T-lymphocyte, b-lymphocyte, natural killer cell, suppressor T-cell, and helper T-cell all showed significant decreases in absolute numbers for more than one week as compared to the preoperative values. Serum IAP level was elevated for more than two weeks after operation. Serum IL-2 decreased but serum sIL-2R increased in the postoperative period. It is concluded that there is a period of immunosuppression after open heart surgery which lasts for at least one week and perhaps more than two weeks.