Evaluation of the dose - response potency of intrathecally administered clonidine by itself during first stage of labor with respect to analgesia and maternal and fetal side effects

Intrathecal clonidine produces dose-dependent postoperative analgesia and enhances labor analgesia from intrathecal sufentanil. We evaluated the dose-response potency of intrathecally administered clonidine by itself during first stage of labor with respect to analgesia and maternal and fetal side effects. Forty-five parturients requesting labor analgesia were studied. In a combined spinal-epidural technique, patients with <5 cm cervical dilatation were assigned to receive one of the following intrathecal solutions: either 75 micro g clonidine [n = 15]; 150 micro g clonidine [n = 15]; and 250 micro g clonidine [n = 15]. Visual analog scores for pain, blood pressure, heart rate, ephedrine requirements, sensory levels, incidence of nausea, pruritus and sedation, fetal heart rate tracings continuously, and maternal and cord blood concentrations of clonidine were recorded. Duration of analgesia was defined as time from intrathecal clonidine administration until request for additional analgesia. We found that clonidine produced a reduction in VAPS with all three doses. The duration of analgesia was significantly longer in patients receiving 250 micro g [median, 150; range, 85-220 min] and 150 micro g [median, 120; range; 65-190 min] than 75 micro g [median 50; range, 30 - 160 min], and VAPS was lower in the 250 micro g than in the 75 micro g group. As regards the sensory levels, no patient in any group had sensory changes above T[3]. In the 250 micro g group, hypotension required significantly more often treatment with ephedrine than in the other groups. Also, bradycardia and sedation were more in 250 micro g group than the other two groups. No adverse events or fetal heart rate abnormalities occurred. Clonidine levels were undetectable in maternal and cord serums. In conclusion, the current study showed that 75 micro g to 250 micro g intrathecal clonidine produces dose-dependent analgesia during first stage of labor. Although duration and quality of analgesia were more pronounced with 150 and 250 micro g than with 75 micro g, the high incidence of hypotension, bradycardia and sedation requires caution with the use of 250 micro g for labor analgesia

Intraperitoneal lidocaine for pain ralief during and after tubal sterilization

We conducted a randomized, blinded, placebo-controlled study to evaluate the effectiveness of intraperitoneal lidocaine, IM meperidine, or both drugs together for pain relief [intraoperative and postoperative] in postpartum tubal ligation. Sixty postpartum patients scheduled to have tubal ligation were randomly divided into four groups to receive IM isotonic sodium chloride solution [2 mL] and intraperitoneal instillation of 40 mL of isotonic sodium chloride solution [Group I]; IM meperidine [100 mg in 2 mL] and intraperitoneal instillation of 40 mL of isotonic sodium chloride solution [Group II]; IM injection of isotonic sodium chloride solution and intraperitoneal instillation of 1% lidocaine in 40 mL [Group III] and both imeperidine and intraperitoneal lidocaine instillation [Group IV]. The rninilaparotomy was performed after local infiltration with 20 ml of lidocaine. A numerical rating score was used to rate pain on a 0 - 10 scale during and after the surgical procedures. During the surgical procedures, the mean pain scores were 1.8 in group III and 0.7 in group IV. These pain scores were significantly lower than those in groups I and II, which were 6.4 and 6.0, respectively [p < 0.001]. Postoperative mean pain scores at 24 h rest were 2.1 in group III and 0.8 in group IV. These pain scores were significantly lower than those in groups I and II, which were 6.5 and 6.4, respectively [p < 0.001]. Postoperative mean pain scores at 24 h movement were 2.9 in group III and 1.6 in group IV. These pain scores were significantly lower than those in groups I and II, which were 7.5 and 7.3 respectively [p < 0.001]. The plasma lidocaine concentrations reached a maximum in groups III and IV 30 min after instillation begun. The highest mean plasma lidocaine level was 2.6 ug/ml [range 1.2 - 3.6]. In conclusions pain relief was inadequate in patients undergoing post-partum tubal ligation under local anesthesia, even after the administration of IM meperidine. Intraperitoneal lidocaine, however, effectively, decreased intraoperative and postoperative pain in these patients