The Influence of Surgical Stress on T Cells: Enhancement of Early Phase Lymphocyte Activation

Which has the least immunity depression during postoperative analgesia—morphine, tramadol, or tramadol with lornoxicam?

BACKGROUND

Analgesics are commonly used to provide pain relief after surgery. These drugs produce some extended depression of immunity. A prospective randomized controlled trial was designed to observe expressions of T-lymphocyte subsets (CD3(+), CD3(+)CD4(+) and CD3(+)CD8(+)), natural-killer cells (CD3(-)CD16(+)CD56(+)), and activated T-lymphocytes (CD3(+)CD25(+)) of patients undergoing gastric cancer surgeries and receiving patient-controlled intravenous analgesia (PCIA).

METHODS

Forty-five patients undergoing elective gastric cancer surgeries under general anesthesia were randomly allocated into 3 groups. Group I received PCIA using morphine after surgery, group II using tramadol, and group III using tramadol with lornoxicam. The analgesic efficacy was evaluated by visual analog scale (VAS) and Bruggrmann comfort scale (BCS). Expressions of CD3(+), CD3(+)CD4(+), CD3(+)CD8(+), CD3(-)CD16(+)CD56(+), and CD3(+)CD25(+) were measured as percentages of total lymphocytes by flow cytometer at 5 time points.

RESULTS

There was no significant difference in analgesic efficacy and the baselines of CD3(+), CD3(+)CD4(+), CD3(+)CD8(+), CD3(-)CD16(+)CD56(+), and CD3(+)CD25(+) in all groups. Compared with the baseline, CD3(+)CD8(+) had no changes in all groups at any time point. Ninety minutes after incision, CD3(+), CD3(+)CD4(+), CD3(-)CD16(+)CD56(+), and CD3(+)CD25(+) were lower in all groups (P<0.05). 24 h after surgery, CD3(+), CD3(+)CD4(+), CD3(-)CD16(+)CD56(+), and CD3(+)CD25(+) were lower in group I and group II (P<0.05); meanwhile CD3(+), CD3(+)CD4(+), and CD3(+)CD25(+) returned to the baseline but CD3(-)CD16(+)CD56(+) was still low (P<0.05) in group III. 48 h after surgery, CD3(+), CD3(+)CD4(+), CD3(-)CD16(+)CD56(+), and CD3(+)CD25(+) returned to the baseline in group II and group III, but not in group I (P<0.05). 72 h after surgery, CD3(+), CD3(+)CD4(+), CD3(+)CD4(+)/CD3(+)CD8(+) returned to the baseline, but CD3(+)CD25(+) and CD3(-)CD16(+)CD56(+) were still low in group I (P<0.05).

CONCLUSION

PCIA using lornoxicam with tramadol has the same good analgesic efficacy and less immunity depression than PCIA using morphine or tramadol.

Off-pump coronary artery bypass grafting does not reduce lymphocyte activation

OBJECTIVE

In this study, we test the hypothesis that off-pump coronary bypass surgery might result in less lymphocyte activation than on-pump coronary surgery. We also study the behavior of lymphocyte activation markers during and after surgery.

BACKGROUND

Coronary artery bypass surgery is known to be associated with changes of inflammatory mediators, immune function, and early phase lymphocyte activation, which could cause postoperative lymphopenia and lymphocyte unresponsiveness.

METHODS

We studied lymphocyte activation response in 28 patients randomized to off-pump (n = 13) or on-pump (n = 15) coronary artery bypass surgery. Expression of CD25, CD26, CD69, and DR on T (CD3+) and B (CD19+) lymphocytes on peripheral blood was assessed through flow cytometry.

RESULTS

The response of T lymphocytes and their activation markers, as well as B lymphocytes and their activation markers, was similar after on- and off-pump surgery. Overall, T lymphocytes decreased to the lowest level 9 h after surgery and tended to increase later. For B lymphocytes, there was early reduction with increase on the 1st postoperative day. There was early activation of CD69+ and late activation of CD25+ on T lymphocytes. For B lymphocytes, there was early activation of CD69+ and late activation of DR+.

CONCLUSIONS

(1) Compared to on-pump cardiopulmonary bypass, off-pump surgery does not reduce lymphocyte activation. (2) Coronary bypass surgery causes the early activation of lymphocytes, as evidenced by the increased expression of lymphocyte activation markers.

Effects of sevoflurane general anesthesia: immunological studies in mice

Based on the immunomodulatory effects of anesthesia and surgery, a study was undertaken to assess the effect of sevoflurane anesthesia on the immune system in a murine model without surgery. Adult male mice were anesthetized with 3% sevoflurane (1.2 minimal alveolar concentration, MAC) in oxygen for 40 min, whereas nontreated animals served as controls. After sevoflurane anesthesia, peripheral blood leukocyte counts, the splenic composition and in vitro macrophage phagocytic activity and lymphoproliferative response were assessed. The in vivo specific immune response to sheep red blood cells (SRBC), a conventional T-dependent antigen was determined. In addition, liver, spleen, thymus and kidney histopathology and also hepatic and renal functions after anesthesia were studied. Sevoflurane diminished the number of peripheral blood lymphocytes and splenic B-cell counts, enhancing CD4+ lymphocytes in spleen. The in vitro functionality of macrophages and the mitogen-induced lymphoproliferative response were preserved, while the in vivo immune response to SRBC was enhanced in treated animals. Microscopic studies revealed conserved architecture of the spleen, thymus, lymph node, liver and kidney, and there were no differences in serum parameters of hepatic and renal functions between treated and control groups. Our results suggest that 3 days after the anesthetic exposure, animals treated with sevoflurane modulated their peripheral blood leukocyte counts, splenic lymphoid composition and the characteristics of the specific response to SRBC, while there was no evidence of hepatic or renal toxicity.

Acute activation of peripheral lymphocytes during treatment of diabetic ketoacidosis

Activated peripheral T-lymphocytes are increased in both pre-insulin-dependent diabetes mellitus (IDDM) patients and in recently diagnosed IDDM patients, as well as in various forms of acute stress. We studied the in vivo T-lymphocyte activation in six patients in severe diabetic ketoacidosis (DKA) prior to treatment, after 24 h of treatment and > or =5 days after admission. Five of the six patients showed an increased percentage of activated T-lymphocytes based on the expression of HLA-DR at 24 h of treatment when compared to the admission percentage of activation (P<.05). There was no correlation to the admission serum glucose, osmolality, or electrolytes. Serum pH showed a trend toward an inverse correlation, but was not statistically significant. We speculate that T-lymphocyte activation plays a role in the progression of the acute complications of subclinical brain edema and interstitial pulmonary edema of DKA. This process could also be another factor in the progression of the chronic complications of IDDM in addition to the well-established effects of hyperglycemia and hypertension.