The effects of pre-emptive epidural sufentanil on human immune function.

BACKGROUND: Surgical stress and general anaesthesia suppress immune functions, including natural killer cell (NK) activity. This suppression could be attributed, at least in part, to the effect of opiates. METHODS: Twenty patients undergoing abdominal hysterectomy received epidural sufentanil (50 microg) either before (pre-emptive) or at the end (control group) of surgery. Post-operative pain relief was provided using sufentanil from a patient-controlled epidural analgesia (PCEA) system. Systemic immunity was assessed by determining leucocyte counts, NK cell counts and activity, lymphocyte response to mitogen stimulation, and secretion of pro-inflammatory cytokines. RESULTS: In the pre-emptive group there was a significant decrease in NK activity on the first and third post-operative day (P < 0.05) compared with baseline values and on the third postoperative day (P < 0.05) compared with the control group. The number of total leucocytes and neutrophiles increased in both groups post-operatively, but no differences were found in the levels of mononuclear lymphocyte populations or in their mitogen responses. Interleukin-6 (IL-6) concentration increased in both groups after the operation. In addition, at the end of the surgery the IL-6 level was greater in the control group than in the pre-emptive group. Interleukin-1 (IL-1) levels had decreased significantly at the end of surgery and 4 h later compared with baseline levels in the pre-emptive, but not in the control group. CONCLUSIONS: Pre-emptive epidural sufentanil during combined propofol and isoflurane anaesthesia had minor effects on the immune response after hysterectomy. The lower production of pro-inflammatory cytokines (IL-1, IL-6) in the pre-emptive group compared with the control group is beneficial, but its clinical importance remains to be determined.

Pre-emptive effect of epidural sufentanil in abdominal hysterectomy.

BACKGROUND: Experimental studies suggest pre-emptive administration of analgesics is effective but clinical evidence is less convincing. METHODS: Forty-one patients undergoing abdominal hysterectomy were allocated randomly in a double-blind fashion to receive sufentanil 50 micrograms via a lumbar epidural catheter before or at the end of surgery. RESULTS: Sufentanil consumption from a patient-controlled epidural analgesia (PCEA) system and numerical pain scores at rest and during movement over the initial 72 h were similar in the two groups. When the study period was divided into five time intervals, sufentanil consumption in the pre-emptive group was significantly less than in the control group between 8 and 16 h after surgery (P = 0.04). Furthermore, the number of failed bolus attempts from the PCEA device was significantly lower and patient satisfaction was significantly better in the pre-emptive group during the 72 h of PCEA treatment (P < 0.05). In addition, the median decrease in ACTH and cortisol on the first postoperative morning relative to baseline values was greater in the pre-emptive group than in the control group (P < 0.05). In subjects who had a Pfannenstiel incision, touch and pain sensitivity in the wound area were less in the pre-emptive group over the first 4 postoperative days (P < 0.05). CONCLUSIONS: We conclude that pre-emptive analgesia with epidural sufentanil was associated with a short-term sufentanil-sparing effect, and could have reduced stress hormone responses and wound sensitization after abdominal hysterectomy.