We conducted a randomized, double-blind trial to compare analgesia and side effects produced by ketorolac and morphine during postoperative patient-controlled analgesia (PCA). Fifty-one patients (ASA classes I and II) undergoing elective intraabdominal procedures were assigned to one of two groups. When postoperative pain first increased to 4/10 (by visual analog scale [VAS]), patients were randomly assigned to one of two groups. Group 1 (n = 25) received up to two intravenous (IV) boluses of 5 mg of morphine followed by IV morphine PCA, whereas those in Group 2 (n = 26) received up to two IV boluses of 30 mg ketorolac, then IV ketorolac PCA. Up to two rescue doses of morphine (5 mg per dose, subcutaneously) were given in either group when pain during deep inhalation exceeded 5/10 on VAS. Ten patients from Group 1 required rescue doses of morphine compared to 22 patients from Group 2 (P < 0.0011). Two and 16 patients from Groups 1 and 2, respectively, were withdrawn because of inadequate analgesia (P < 0.01). Mean pain scores were less in Group 1 than in Group 2 at each time, but only significantly so at 15 min (P < 0.0021), 30 min (P < 0.0336), and 24 h (P < 0.0358) after starting PCA. Time to acceptance of oral liquids was equivalent in Groups 1 and 2 (22 h and 21 h, respectively). IV ketorolac PCA, although well tolerated, has limited effectiveness as the sole postoperative analgesic after intraabdominal operations.
Dose-response curves of three receptor-selective opioids were established in a group of nonburned and a group of burned rats. Morphine (mu-agonist), biphalin (mu- and delta-agonist), and U50488H (kappa-agonist) were administered to each group, and analgesia was measured by tail flick latency testing. Each opioid had a significant increase in potency (i.e., a decrease in ED50 values) in the burned (15% body surface area) compared with the nonburned groups. Moderate doses of each drug (i.e., ED50 doses estimated from nonburned group data) in each case augmented stress-induced analgesia in the burned group. Analgesic doses failed to prevent a significant increase in plasma beta-endorphin and corticosterone after larger surface area (25%) burns. Regardless of receptor specificity, opioid analgesic potency is increased acutely after burn injuries.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.