Anesthesia and analgesia
-
Anesthesia and analgesia · Oct 1999
Randomized Controlled Trial Comparative Study Clinical TrialIntravenous infusion of phenytoin relieves neuropathic pain: a randomized, double-blinded, placebo-controlled, crossover study.
Neuropathic pain responds inconsistently to opioids and nonsteroidal antiinflammatory drugs. However, oral anticonvulsants have a proven analgesic effect on neuropathic pain, but may not be practical in an acute flare-up. Phenytoin was the first oral anticonvulsant used as an analgesic for neuropathic pain. There have been few studies on the parenteral analgesic effect of this drug. In this randomized, double-blind, placebo-controlled, crossover study of 20 patients with acute flare-ups of neuropathic pain, we compared a 2-h placebo infusion with a 2-h infusion of 15 mg/kg phenytoin. Overall pain, shooting pain, burning pain, paresthesia, numbness, and sensitivity were measured using a 10-cm linear visual analog score. Numbness and sensitivity were reduced in the placebo group during infusion, but not in the 7 days after infusion. In the phenytoin group, there were significant reductions in burning pain (P < 0.05), shooting pain (P < 0.001), sensitivity (P < 0.001), numbness (P < 0.05), and overall pain (P < 0.005) during the infusion period. The reduction in overall pain persisted for 1 day, in sensitivity for 2 days, and in shooting pain for 4 days after infusion. We conclude that IV infusion of 15 mg/kg phenytoin has an analgesic effect in acute flare-ups of neuropathic pain and that this relief outlives both the infusion time and plasma half-life of phenytoin. ⋯ Oral phenytoin can relieve neuropathic pain. The aim of this study was to examine the effect of IV phenytoin on neuropathic pain. The results indicate that IV phenytoin may be used to treat flare-ups of chronic neuropathic pain.
-
Anesthesia and analgesia · Oct 1999
Randomized Controlled Trial Comparative Study Clinical TrialDetermination of the effective therapeutic dose of intrathecal sufentanil for extracorporeal shock wave lithotripsy.
Intrathecal (IT) sufentanil provides effective analgesia for extracorporeal shock wave lithotripsy. However, the optimal dose of sufentanil has not been established. We designed a prospective, randomized, double-blinded study to determine the optimal dose of IT sufentanil. Sixty men were randomized to receive 12.5,15,17.5, or 20 microg of IT sufentanil (n = 15 for each group) via a combined spinal epidural technique. Inadequate analgesia was treated with IV propofol, and the epidural was activated for a pain score greater than 6 on a 10-point verbal analog pain scale. Intraoperative and postoperative visual analog pain scale scores were significantly higher in the 12.5-microg group compared with 20-microg group (3.2 +/- 1.6 vs 1.6 +/- 1.2, P < 0.05, and 1.1 +/- 0.5 vs. 0.5 +/- 0.4, P < 0.05, respectively). The smaller-dosage groups of IT sufentanil required significantly more supplemental boluses of propofol compared with the 20-microg group (67%, 53%, and 40% vs 6%, respectively, P < 0.05). However, pruritus was significantly diminished in the smaller-dosage groups compared with the 20-microg group (55%, 60%, and 67% vs 100%, P < 0.05). The time to discharge was significantly shorter in the 15-microg group compared with the 20-microg group (84 +/- 40 min vs 126 +/- 48 min, P < 0.05). These results suggest that 15 microg of IT sufentanil may be the optimal IT dose for patients undergoing extracorporeal shock wave lithotripsy. ⋯ Many anesthetic techniques are used for extracorporeal shock wave lithotripsy (ESWL). We have previously shown that intrathecal sufentanil was effective for ESWL, but was associated with a high incidence of itching. We tested 60 patients in four spinal sufentanil dose groups and found that doses of 15 and 17.5 microg provided the most effective analgesia with the fewest side effects for ESWL, with only mild itching.
-
Anesthesia and analgesia · Oct 1999
Randomized Controlled Trial Comparative Study Clinical TrialVideotape increases parental knowledge about pediatric pain management.
Pediatric pain management often depends on parents recognition and assessment of their child's pain and their beliefs as to whether the pain should be treated. Parental misconceptions concerning pain assessment and pain management may therefore result in inadequate pain treatment, particularly in patients who are too young or too developmentally handicapped to self-report their pain. We hypothesized that viewing a concise, educational videotape would provide parents with instructive information that could correct misconceptions concerning pain and pain management in children. To do this, we evaluated the impact of an educational videotape on parental responses to a questionnaire about pediatric pain management. Parents of children scheduled for inpatient, postoperative hospital care were studied. After answering 30 questions, parents were randomly assigned to either view (Group 1) or not view (Group 2) a 19-min educational videotape. Immediately after viewing the videotape (Group 1), or 30 min after taking the first test (Group 2), parents were asked to answer the same questionnaire a second time. The effect of seeing the videotape was assessed by comparing post-pre test score differences using paired t-test. One-hundred parents were studied. Randomization was effective in assigning equitable groups. Initial scores of percent answers correct in each group were not different ([mean +/- SD] Group 1 [n = 50]: 68.7% +/- 18.8% vs Group 2 [n = 50]: 61.5% +/- 22.7%; P = 0.09). Viewing the videotape effectively increased test scores: paired t-test within groups demonstrated a significant difference in Group 1 (22.4% +/- 16.5%, P < 0.0001), whereas Group 2 scores changed to a much lesser degree (2.7% +/- 8.3%, P = 0.0271). All parents who viewed the videotape stated that it was informative regarding their understanding of their child's pain management. This study demonstrates the effectiveness of an educational videotape in changing parental knowledge concerning postoperative pediatric pain. This effective and efficient teaching medium may be useful in improving pain management in postoperative pediatric surgical patients. ⋯ Pediatric pain management often depends on parents recognition and assessment of their child's pain and their beliefs as to whether the pain should be treated. This prospective, randomized, controlled study demonstrated the effectiveness of an educational videotape in changing parental knowledge concerning postoperative pediatric pain. This effective and efficient teaching medium may be useful in preventing inadequate pain management in postoperative pediatric surgical patients.
-
Anesthesia and analgesia · Oct 1999
Randomized Controlled Trial Clinical TrialHemodynamic responses induced by dopamine and dobutamine in anesthetized patients premedicated with clonidine.
To test the hypothesis that the pharmacological effects of dopamine (DOA) and dobutamine (DOB) are altered when there is inhibition of the release of norepinephrine from nerve endings, we examined the hemodynamic responses to DOA and DOB in anesthetized patients premedicated with oral clonidine. Seventy adult patients were assigned to one of two groups (oral premedication with clonidine 5 microg/kg or no premedication). After the induction of general anesthesia, heart rate and systemic blood pressure (BP) were measured for 10 min after each of five IV infusions (3 and 5 microg x kg(-1) x min(-1) of DOA; 0.5, 1, and 3 microg x kg(-1) x min(-1) of DOB) in a randomized, double-blind manner. In patients given clonidine, the mean BP increases induced by DOA 5 microg x kg(-1) x min(-1) were significantly attenuated (P < 0.01), whereas the mean BP increases induced by DOB-0.5, 1, or 3 microg x kg(-l) x min(-1) were significantly enhanced (P < 0.01 or 0.05). The heart rate responses to DOA and DOB did not differ between patients with or without clonidine. Premedication with clonidine alters the effects on BP to both DOA and DOB. When small doses of DOA or DOB are used in clonidine-premedicated patients, differences of pharmacological profiles need to be considered for perioperative management. ⋯ Our randomized, double-blind study suggests that premedication with clonidine may enhance the effect on blood pressure response to a small dose of dobutamine (direct-acting) and attenuate that to a small dose of dopamine (mixed direct-and indirect-acting) in patients anesthetized with fentanyl and nitrous oxide.
-
Anesthesia and analgesia · Oct 1999
Comparative StudyThe long-term effect of epidural administration of butamben suspension on nerve injury-induced allodynia in rats.
Although local anesthetics can, in some situations, alleviate neuropathic pain, currently available preparations are short-acting and nonselective, producing, for example, motor dysfunction. Clinical studies report that a novel suspension preparation of butamben has the advantage of a prolonged duration of action, and it can be used epidurally, without impairment of motor function. In this behavioral study, we investigated the effect of the epidural administration of a 5% butamben suspension on nerve injury-induced allodynia. Behavioral studies were performed using an established animal model of neuropathic pain, which involves a partial ligation of the sciatic nerve. Nociceptive thresholds to mechanical stimulation were determined by the paw withdrawal method. The allodynia to mechanical stimulation induced by partial nerve ligation was significantly attenuated by daily injections, for 5 days, of 10 microL of butamben suspension. The analgesia lasted at least 7 days after the final injection. Daily injections of 10 microL of vehicle, for 5 days, had no significant effect on allodynia. During the period of daily injections, both the butamben and vehicle treated rats had temporary impairment of motor coordination compared with untreated controls. Motor function recovered after the final injection. Neither daily injections of butamben for 2 or 3 days, nor smaller volumes for 5 days (2.5-5 microL), had a long-lasting effect. We conclude that repeated epidural administration of butamben suspension for several days provides long-lasting analgesia in rats with nerve injury-induced allodynia to mechanical stimulation. ⋯ In this animal behavioral study, using rats with nerve injury-induced pain, we examined the possible long-term analgesic effects of epidural administration of a suspension of the local anesthetic, butamben. We found that multiple doses for several days were required to provide a prolonged analgesia.