Intrathecal clonidine combined with sufentanil for labor analgesia

Background: Intrathecal sufentanil provides rapid-onset and complete analgesia for the first stage of labor, The dose required to produce this effect can be associated with maternal respiratory depression, hypotension, nausea, or pruritus. Because clonidine potentiates the analgesic effects of opioids without increasing their side effects, the authors wanted to determine the efficacy of low doses of intrathecal clonidine (15 and 30 mu g) combined with sufentanil. Methods: Ninety-eight parturient requesting labor analgesia were studied. In a combined spinal-epidural technique, patients mere randomly assigned to receive one of the following intrathecal solutions: either 15 mu g clonidine (n = 10); 30 mu g clonidine (n = 10); 2.5 mu g sufentanil (n = 13); 5 mu g sufentanil (n = 13); 2.5 mu g sufentanil and 15 mu g clonidine (n = 13); 2.5 mu g sufentanil and 30 mu g clonidine (n = 13); 5 mu g sufentanil and 15 mu g clonidine (n = 13); or 5 mu g sufentanil and 30 mu g clonidine (n = 13). Visual analog scores for pain, blood pressure, heart rate, sensory levels, incidence of nausea and pruritus, and motor blockade, and maternal and cord blood concentrations of clonidine were recorded. Results: patients receiving 30 mu g intrathecal clonidine with 2.5 or 5 mu g intrathecal sufentanil had significantly longer-lasting analgesia (145 +/- 36 and 145 +/- 43 min vs. 104 +/- 35 for those receiving 5 mu g intrathecal sufentanil alone). Clonidine levels were undetectable in maternal serum. Conclusions: Thirty micrograms of intrathecal clonidine combined with 2.5 or 5 mu g intrathecal sufentanil significantly increased the duration of analgesia during the first stage of labor without adverse maternal or fetal effects.