James H. Chung

An Evaluation of Morphine and Oxymorphone Administered via Patient-Controlled Analgesia (PCA) or PCA plus Basal Infusion in Postcesarean-Delivery Patients

The analgesic efficacy and adverse effects of morphine and oxymorphone in 32 patients who received traditional patient-controlled analgesia (PCA) following cesarean delivery were compared with those in 32 other patients receiving the same agents via PCA plus basal opioid infusion (PCA + BI). All patients were operated upon during epidural anesthesia with 2% lidocaine and 1:200,000 epinephrine to achieve a T4 sensory level. Upon first complaint of pain in the recovery room, patients were given a titrated iv loading dose of the assigned opioid until comfortable and were then provided with a programmable PCA device. Group I (PCA) consisted of two subsets in which incremental boluses of morphine (1.8 mg, n = 16) or oxymorphone (0.3 mg, n = 16) could be self-administered via conventional PCA. Patients in group II (PCA + BI) received a basal infusion of morphine (0.6 mg/hour, n = 16) or oxymorphone (0.1 mg/hour, n = 16) in addition to self-administered boluses of 1.8 and 0.3 mg, respectively. Patients were evaluated for 24 h following initiation of analgesic therapy, and 10-cm visual analog scales (VAS) were utilized at selected intervals to assess pain at rest, pain during movement, and satisfaction with therapy. The level of sedation and incidence of nausea/vomiting and pruritus were also recorded. Patients utilizing PCA + BI noted significant reductions in resting pain scores with oxymorphone and decreased pain during movement with both opioids when compared with individuals using PCA alone (P less than 0.05). There were no significant differences between treatment groups in 24-h dose requirements or patient satisfaction with therapy (P = ns).(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of morphine, meperidine, and oxymorphone as utilized in patient-controlled analgesia following cesarean delivery.

Seventy-five patients (n = 75) undergoing elective cesarean delivery during epidural anesthesia were randomly assigned to receive one of three opioid analgesics via patient-controlled analgesia (PCA) when they first complained of pain in the recovery room. Following administration of an analgesic loading dose, patients were allowed to self-administer morphine 1.8 mg, meperidine 18 mg, or oxymorphone 0.3 mg iv every 8 min as required. Data collected during the 24-h observation period included visual analog scale (VAS) pain scores at rest and during movement, VAS patient satisfaction scores, total drug administered, the ratio of attempts/injections, and the incidence of nausea/vomiting, sedation, and pruritus. After adjusting for narcotic potency, no differences in 24-h dose requirements were noted between treatment groups (NS). All patients achieved an excellent level of analgesia at rest (NS); however, onset was most rapid with oxymorphone (P less than 0.05). The percentage of patients reporting severe pain during movement was highest in the meperidine group (P less than 0.05). Oxymorphone was associated with the highest incidence of nausea and vomiting (P less than 0.05), whereas increased sedation and pruritus were noted with morphine. Patient satisfaction with drug effect demonstrated significant negative correlations with resting pain scores and degree of sedation. Whereas morphine is a more commonly utilized PCA analgesic, the excellent analgesia, low incidence of sedation, and high patient satisfaction provided by meperidine and oxymorphone suggested useful alternatives.

Comparison of epidurally administered sufentanil, morphine, and sufentanil-morphine combination for postoperative analgesia.

Postoperative analgesia provided by epidurally administered sufentanil and/or morphine was evaluated in 45 patients recovering from major gynecologic surgery. At the first complaint of pain in the Postanesthesia Care Unit, patients received a single epidural bolus of 30 μg sufentanil (group A), 5 mg morphine (group B), or 30 μg sufentanil plus 3 mg morphine (group C) in a randomized blinded fashion. Analgesic efficacy was assessed throughout the 24-h study period with 10-cm visual analog scales. The need for additional postoperative analgesia (patient‐controlled analgesia, 1 mg of morphine every 6 min as necessary) and the incidence of adverse effects were also assessed.Patients receiving sufentanil (groups A and C) had significantly faster onset of analgesia than did patients given morphine alone (group B, P<0.05). Group B subjects experienced the longest duration of analgesia (B us A and C, P<0.05) and required significantly less patient‐controlled analgesia (morphine) than patients in group A (P<0.05). No patient developed clinically significant respiratory depression or excessive sedation, and there were no intergroup differences in incidence of pruritus or nausea (P value not significant). The data indicate that a mixture of sufentanil and morphine provides either a more rapid onset of epidural analgesia or reduced patient‐controlled analgesia narcotic requirement than respective doses of each agent administered alone.

The effect of an intermediate dose of labetalol on heart rate and blood pressure responses to laryngoscopy and intubation.

STUDY OBJECTIVE To evaluate the efficacy of an intermediate dose of labetalol (0.4 mg/kg) for attenuation of heart rate (HR) and blood pressure (BP) responses to laryngoscopy and intubation. DESIGN Randomized, double-blind, placebo-controlled study. SETTING Inpatient gynecology service at a university medical center. PATIENTS Two groups of 18 patients each undergoing elective surgery under general anesthesia. INTERVENTIONS Patients received either 0.4 mg/kg of labetalol or an equal volume of normal saline 5 minutes prior to laryngoscopy and intubation. MEASUREMENTS AND MAIN RESULTS HR and BP were measured upon arrival in the operating room (OR) (baseline) and at 1 minute intervals thereafter for 4 minutes prior to intubation and through 10 minutes following intubation. The labetalol group had a significantly lower HR from induction through 1 minute following intubation. Intragroup differences in HR were greatest immediately following laryngoscopy and intubation (33% increase above baseline for the placebo group vs 1% for the labetalol group, p less than 0.05). At the same time, a significant increase in mean arterial pressure (MAP) from baseline was noted in both groups (29% for the placebo group vs 23% for the labetalol group), but the difference between the groups was not significant. CONCLUSIONS An intermediate dose of labetalol blunted the HR response to laryngoscopy and intubation during rapid-sequence induction in healthy patients but had a minimal effect on BP.

Subarachnoid meperidine-morphine combination. An effective perioperative analgesic adjunct for cesarean delivery.

Background and Objectives. Low‐dose subarachnoid morphine provides effective perioperative analgesia but may be associated with a transient period of inadequate pain relief between the regression of local anesthetic block and the onset of morphines analgesic effect. We hypothesized that this period of suboptimal analgesia could be avoided by adding meperidine, a rapid‐acting, intermediate‐duration opioid. Methods. In a double‐blind, randomized trial, 49 patients scheduled for elective cesarean delivery received subarachnoid 0.75% bupivacaine, 12 mg in 8.25% dextrose, with either meperidine 10 mg, morphine 0.15 mg, or meperidine 10 mg plus morphine 0.15 mg. Visual analog scale scores for pain and satisfaction were obtained at skin incision, delivery, uterine exteriorization, on arrival in the postanesthesia care unit, and 2, 4, 6, 12, and 24 hours after drug administration. Neonatal Apgar scores and adverse effects were also noted. Postoperative intravenous patient‐controlled analgesia (PCA) requirements were recorded for 24 hours. The data were analyzed by chi‐square analysis Fishers exact test, the Wilcoxon rank sum test, and analysis of variance with Tukeys adjustment for multiple comparisons. Results. There were no significant differences in the incidence and severity of side effects, including nausea, vomiting, pruritus, and sedation. Respiratory depression was not observed. Patients treated with morphine alone were least comfortable (P < .006), expressed the lowest satisfaction scores at early observations (P < .002), and required more PCA meperidine (P < .001) than any other group. Patients treated with meperidine alone were comfortable at early observations but required the greatest total amount of PCA meperidine over the first 24 hours (P < .05). Patients in the meperidine‐morphine combination group reported the lowest pain scores and highest satisfaction scores at 4‐hour and 6‐hour observations (P < .03) and required the least total amount of PCA meperidine. Conclusion. The subarachnoid combination of meperidine‐morphine provided more uniform analgesia, higher satisfaction, and a lower requirement for intravenous narcotic supplementation than either morphine or meperidine alone in patients recovering from cesarean delivery.

Epidural sufentanil for postoperative analgesia : dose-response in patients recovering from major gynecologic surgery

To determine the lowest effective dose of epidural sufentanil given for analgesia, 41 patients undergoing elective abdominal gynecologic surgery during continuous epidural anesthesia (lidocaine 2%) were randomly assigned to one of four postoperative treatment groups. Patients received an epidural bolus of either 25 (group A), 40 (group B), 55 (group C), or 70 micrograms (group D) sufentanil in 10 mL of saline. They were evaluated for the next 8 h using a 10-cm visual analogue scale. Except for two individuals in group A, all patients achieved a visual analogue scale score of 1 cm or less during the study interval. The onset of analgesia was most rapid in the two higher dose groups (A vs C and D; P less than 0.05). Pairwise comparison between groups showed a significant difference in the time needed to achieve maximum pain relief between the lowest and highest treatment groups (A vs D; P less than 0.05). Duration of analgesia was also significantly longer in groups C and D than in group A (208.0 +/- 21.1 and 224.0 +/- 14.7 vs 140.0 +/- 10.7 min; P less than 0.05). There were no differences among groups with regard to mean respiratory rate, level of sedation, 24-h narcotic requirements, or incidence of nausea, vomiting, and pruritus (P = NS). A single patient in group D suffered profound respiratory depression within seconds of administration. We conclude that, in patients recovering from lower abdominal surgery, a single 40-55-micrograms epidural bolus of sufentanil provides 3-3.5 h of effective analgesia, and that larger doses are not warranted.

Continuous epidural infusion of 0.05% bupivacaine plus hydromorphone for labor analgesia: an observational assessment in 1830 parturients.

IMPLICATIONS We evaluated a continuous epidural infusion containing bupivacaine 0.05% plus the opioid hydromorphone in 1830 women requesting pain relief during labor and delivery. The infusion provided effective analgesia with minimal adverse events for patients differing in parity and at varying stages of labor. Pain relief was maintained in most patients without the need for epidural reinforcement with more concentrated doses of local anesthetic.

Combination of Two Standard Pneumatic Calf Compression Devices to Fit the Morbidly Obese

To the Editor:—In his editorial, Eisenach highlighted an interesting paradox; while attempting to produce profound analgesia with high doses of potent opioids, it is possible to produce a “preemptive hyperalgesic” effect. In the two human studies referenced, high doses of systemic remifentanil and fentanyl produced acute hyperalgesia. In a previous human study, we found evidence that intrathecal fentanyl administration can produce acute spinal hyperalgesia. Administration of 25 mg intrathecal fentanyl during Cesarean section increased postoperative intravenous morphine requirements by 63% between 6 and 23 h postdelivery. In his editorial, Bernards mentions his concern that “alfentanil and sufentanil (and to some extent fentanyl)” are used in the epidural space, “. . .despite mounting evidence that these opioids do not produce analgesia by a selective spinal mechanism.” However, there is evidence that epidural fentanyl, when it is administered in the minimal effective dose, has a selective spinal action. In humans, lumbar cerebrospinal fluid levels of fentanyl increase rapidly after epidural fentanyl administration, and Bernards and Sorkin have shown that, in pigs, “epidural fentanyl moves rapidly from the epidural space to the spinal cord.” Prolonged postoperative epidural fentanyl administration can produce plasma levels similar to those of systemic administration. However, spinal cord levels of fentanyl still would be expected to be higher after epidural than after systemic administration. It is therefore surprising that the analgesic effectiveness of epidural and systemic fentanyl often are reported to be comparable, even if plasma levels are similar. This is especially so if, as suggested by Bernards, there is synergy between spinal and supraspinal opioid analgesia in humans. It may be that, by producing relatively high spinal compared with systemic levels of fentanyl, epidural fentanyl administration can induce acute selective spinal hyperalgesia. The greater the magnitude of selective spinal hyperalgesia induced, the smaller the difference in analgesic effectiveness of epidural and systemic fentanyl would be. This could help to explain why several studies have not found a difference between epidural and systemic fentanyl analgesia. Administration of epidural fentanyl in the minimal effective dose may limit the development of spinal hyperalgesia, thereby facilitating selective spinal analgesia. David W. Cooper, M.B.B.S., F.R.C.A., Consultant Anaesthetist, Department of Anaesthesia, South Cleveland Hospital, Middlesbrough, Cleveland, United Kingdom dr_david_cooper@hotmail.com