Epidural morphine and post-operative pain relief

Epidural morphine was compared with placebo in two randomly selected but similar groups of patients undergoing upper abdominal operations. There was no quantitative or qualitative difference in the analgesia obtained in the two groups of patients but there were significantly diminished long term requirements of intramuscular morphine in those who had been previously given epidural morphine when compared with epidural placebo. The possible causes and implications of this difference are discussed.     

Double-blind comparison of intravenous doses of dezocine, butorphanol, and placebo for relief of postoperative pain

The safety and efficacy of intravenous doses of dezocine (5 or 10 mg), butorphanol (1 mg), and placebo were compared in a double-blind study in 160 patients with moderate to severe postoperative pain. Analgesic efficacy was assessed for 6 hours after each dose. Mean pain relief scores were consistently higher, indicating greater pain relief, for the three active treatment groups than for the placebo group. The 10-mg dezocine dose was the most effective treatment, and 5 mg of dezocine was comparable to 1 mg of butorphanol. In the 2 hours after the first dose, 32% of the 10-mg dezocine group, 53% of the 5-mg dezocine group, 65% of the butorphanol group, and 88% of the placebo group withdrew from the study because of unsatisfactory pain relief. The differences in these percentages were statistically significant (P less than 0.05) between each active therapy group and the placebo group, and between the 10-mg dezocine group and the butorphanol group. Changes in degree of sedation were similar in the three active therapy groups. Adverse reactions were rare, mild, and equally distributed among the four treatment groups. We conclude that 10 mg of dezocine is superior to 1 mg of butorphanol, and that 5 mg of dezocine is as effective as 1 mg of butorphanol for the relief of moderate to severe postoperative pain.     

Tramadol infusion for postthoracotomy pain relief: a placebo-controlled comparison with epidural morphine

We compared continuous IV tramadol as an alternative to neuraxial or systemic opioids for the management of postthoracotomy pain in a prospective, randomized, double-blinded, controlled study. General anesthesia was supplemented by thoracic epidural analgesia with 0.25% bupivacaine. At rib approximation, patients received one of the following: IV tramadol (150-mg bolus followed by infusion, total 450 mg/24 h, n = 29), epidural morphine (2 mg, then 0.2 mg/h, n = 30), or patient-controlled analgesia (PCA) morphine only (n = 30). All patients received PCA morphine and rescue morphine as necessary postoperatively. For the first 24 h, pain and sedation scores and respiratory, cardiovascular, and side effect measures were monitored. There was no significant difference in pain scores and PCA morphine use between tramadol and epidural morphine. Pain scores at rest and on coughing were lower in the Tramadol and Epidural Morphine groups than in the PCA Morphine group at various time points over the first 12 h. The Tramadol and Epidural Morphine groups used significantly less hourly PCA morphine than the PCA Morphine group at specific time points in the first 10 h. Vital capacities in the Tramadol group were significantly closer to baseline values at the 20-h point than in the PCA Morphine group. We conclude that an intraoperative bolus of tramadol followed by an infusion was as effective as epidural morphine and avoided the necessity of placing a thoracic epidural catheter. IMPLICATIONS: A prospective, randomized, double-blinded, placebo-controlled study of postthoracotomy pain relief showed that IV tramadol in the form of a bolus followed by continuous infusion was as effective as epidural morphine. The use of tramadol avoids the necessity of placing a thoracic epidural catheter.     

Patient-controlled epidural analgesia with morphine or morphine plus ketamine for post-operative pain relief

Sixty patients were randomly assigned to two equal groups. Group I received epidural morphine 1 mg after surgery and used a patient-controlled analgesia device programmed to deliver morphine 0. 2 mg h-1, 0.2 mg per bolus. Group II received an epidural loading dose of morphine 1 mg plus ketamine 5 mg and used a patient-controlled analgesia device programmed to deliver morphine 0. 2 mg+ketamine 0.5 mg h-1, morphine 0.2 mg+ketamine 0.5 mg per bolus with a lockout time of 10 min. The mean morphine consumption was 8. 6+/-0.7 mg for group I and 6.2+/-0.2 mg for group II. Although group II utilized significantly less morphine (P < 0.05), pain relief was significantly better in group II than in group I (P < 0.05) in the first 3 h. Vomiting occurred more frequently in group I (26%) than in group II (13%). The frequency and severity of pruritus and level of sedation were similar in the two groups. These findings suggest that patient-controlled epidural analgesia with morphine plus ketamine may provide effective analgesia with a lesser dose of morphine and fewer subsequent side effects, compared with patient-controlled epidural analgesia with morphine alone after lower abdominal surgery.     

On-demand nalbuphine for post-operative pain relief

Twenty-five patients with moderate to severe pain after major upper abdominal surgery chose to receive nalbuphine on demand from a Cardiff Palliator for pain relief. An initial i.v. injection of nalbuphine 20 mg was followed by 5 mg given over 90s in response to each successful demand. A maximum of 20 doses (100 mg) hr-1 of nalbuphine was available, plus additional bolus doses. Twelve patients obtained good pain relief and completed the 5 hour observation period. 13 patients withdrew from the study, 8 because of inadequate pain relief and 2 because of side-effects. At least half the patients who complained of inadequate pain relief at the time had no subsequent memory of the events. Despite high dosage in some cases (up to 200 mg in an hour) no clinically important cardiovascular or respiratory effects were observed.     

Double-blind evaluation of buprenorphine hydrochloride for post-operative pain.

In a double-blind, random assignment study of four groups of 40 patients, relief of severe pain with buprenorphine hydrochloride 0.2 mg or 0.4 mg was evaluated and compared with morphine sulphate 5 or 10 mg. Evaluations included pain intensity, pain relief, sedation and other effects for up to 12 hours after drug administration, following recovery of wakefulness from anaesthesia for major abdominal surgery. Analyses of five parameters showed that the four groups were statistically comparable and that buprenorphine hydrochloride is at least 50 times more potent than morphine sulphate and has a substantially longer duration of analgesic action. Further clinical evaluation is, therefore, recommended.     

Epidural analgesia for post-caesarean pain relief: a comparison between morphine and fentanyl

In 20 post-operative patients who had undergone caesarean section, morphine 2 mg or fentanyl 75 micrograms in 0.9% saline were given epidurally in a randomized study, to compare their effectiveness in providing post-operative pain relief and the incidence of untoward reaction. There was a faster onset of action (P less than 0.01) and the quality of pain relief was substantially better after epidural fentanyl (P less than 0.01). However, the duration of action was markedly longer after epidural morphine (P less than 0.01). There was a significantly greater incidence of urinary retention after morphine administration (P less than 0.05). It is suggested that fentanyl gives better relief of pain than morphine when given epidurally.     

Intrathecal sufentanil and morphine for post-thoracotomy pain relief

In this double-blind randomized study we compared a group of15 patients undergoing thoracotomy who received a spinal injectionof sufentanil 20 µg combined with morphine (200 µg)after induction of general anaesthesia with a control groupof the same size. Post-operative pain was rated on a visualanalogue scale (VAS) and a verbal rating scale at rest and witha VAS on coughing. In the recovery room, patients received titratedi.v. morphine until the VAS score was <30, and were followedby patient-controlled analgesia (PCA) for 72 h. The intrathecalsufentanil and morphine group had a lower intra-operative requirementfor i.v. sufentanil and needed less i.v. morphine for titrationin the recovery room. I.v. PCA morphine consumption and painscores were lower in the active group than in the control groupduring the first 24 h. There were no differences afterthis time. Spirometric data (peak expiratory flow, forced vitalcapacity and forced expiratory volume in 1 s) were similarin the two groups. We conclude that the combination of intrathecalsufentanil and morphine produces analgesia of rapid onset andwith a duration of 24 h. Br J Anaesth 2001; 86: 236–40.     

Tramadol for pain relief in children undergoing tonsillectomy. A comparison with morphine

Introduction Pain control for paediatric patients undergoing tonsillectomy remains problematic. The combination of intra‐operative morphine and rectal diclofenac results in a high incidence of post‐operative nausea and vomiting as well further analgesic requirements. Tramadol is reported to be an effective analgesic and have a side effect profile similar to morphine. It is not classed as a controlled drug and is available in tablet, suppository and injection form. It is currently not licensed for paediatric use in the UK. Methods We conducted a prospective, double blind, randomised controlled trial in children scheduled for elective tonsillectomy or adenotonsillectomy at the Royal Aberdeen Children Hospital. Following local ethics committee approval and obtaining a drug exemption certificate from the Medicines Licensing Agency for an unlicensed drug in paediatrics we recruited 60 patients into three groups: morphine (0.1 mg·kg^?1), tramadol (1 mg·kg^?1) and tramadol (2 mg·kg^?1). These drugs were given as a single injection following induction of anaesthesia. In addition, all patients received diclofenac (1 mg·kg^?1) rectally. The post‐operative analgesic requirements, sedation scores, signs of respiratory depression and nausea and vomiting as well as antiemetic requirements were noted at 4 hourly intervals until discharge. Statistical analysis was performed using chi‐square, Kruskal–Wallis and one‐way anova tests as appropriate. P < 0.05 was considered statistically significant. Results There were no statistical significant differences in age, weight, type of operation or induction of anaesthesia, 4 hourly sedation and pain scores and further analgesic requirements. There were no incidences of respiratory depression. Morphine was associated with a significantly higher incidence of vomiting following discharge to the wards (75% vs 40%, P = 0.03) when compared to both tramadol groups. The differences in anti‐emetic requirements did not reach statistically significant difference (P = 0.078). Conclusions We conclude that tramadol has similar analgesic properties and side effects when compared with morphine. The pharmaceutical presentation and the availability as a non‐controlled substance may make it a useful addition to paediatric anaesthesia if it becomes licensed for paediatric anaesthesia in the UK.     

Tramadol for pain relief in children undergoing tonsillectomy: a comparison with morphine

BACKGROUND: Pain control for paediatric patients undergoing tonsillectomy remains problematic. Tramadol is reported to be an effective analgesic and to have a side-effect profile similar to morphine, but is currently not licensed for paediatric use in the UK. METHODS: We conducted a prospective, double-blind, randomized controlled trial in children who were scheduled for elective tonsillectomy or adenotonsillectomy at the Royal Aberdeen Children Hospital. Following local ethics committee approval and after obtaining a drug exemption certificate from the Medicines Licensing Agency for an unlicensed drug, we recruited 20 patients each into morphine (0.1 mg.kg(-1)), tramadol (1 mg.kg(-1)) and tramadol (2 mg.kg(-1)) groups. These drugs were given as a single injection following induction of anaesthesia. In addition, all patients received diclofenac (1 mg.kg(-1)) rectally. The postoperative pain scores, analgesic requirements, sedation scores, signs of respiratory depression and nausea and vomiting, as well as antiemetic requirements, were noted at 4-h intervals until discharge. RESULTS: There were no statistically significant differences in age, weight, type of operation or induction of anaesthesia, 4-h sedation and pain scores and further analgesic requirements. There were no episodes of respiratory depression. Morphine was associated with a significantly higher incidence of vomiting following discharge to the wards (75% versus 40%, P=0.03) compared with both tramadol groups. CONCLUSIONS: Tramadol has similar analgesic properties, when compared with morphine. The various pharmaceutical presentations and the availability as a noncontrolled substance may make it a useful addition to paediatric anaesthesia if it becomes licensed for paediatric anaesthesia in the UK.     

Epidural morphine for pain relief after lumbar laminectomy

A prospective randomized trial was conducted to evaluate the effectiveness of epidural morphine for pain relief after lumbar laminectomy. Thirty-three male patients were studied in two groups. At the end of surgery, Group 1 patients (15) received 2 mg morphine in 5 ml saline through an epidural catheter. Doses were repeated on demand. Group 2 patients (18) received 10 mg morphine intramuscularly on request in the postoperative period. Pain was assessed at 2, 6, 12, and 24 hours postoperatively by the linear analog of pain scale. There was significantly greater pain relief in Group 1 than in Group 2 after 2, 6, and 12 hours, respectively. Furthermore, Group 2 received larger doses of morphine than Group 1. There was no respiratory or cardiovascular depression detected in patients in either group. Nine patients in Group 1 and five patients in Group 2 had transient postoperative urinary retention that required catheterization. Only one patient in Group 1 had mild pruritus and three patients in Group 2 had nausea.     

Intra-articular morphine for pain relief after knee arthroscopy

BACKGROUND: Peripheral opioid analgesia is well documented. But the clinical usefulness of intra-articular morphine after surgery is uncertain. The aim of the present study was to evaluate the analgesic effects of intra-articular morphine after knee arthroscopy. METHODS: In this parallel-group, double-blind study, 90 patients were randomised to receive either morphine 1 mg, morphine 2 mg or placebo in 5 ml saline intra-articularly at the end of arthroscopic knee surgery. Anaesthetic technique was local infiltration and intra-articular injection of lidocaine. Analgesic efficacy was evaluated by a global pain score, pain intensity (visual analogue scale), and analgesic requirements (paracetamol) during the first 48 h postoperatively. RESULTS: No significant differences between the groups were found for any of the efficacy variables. A majority of the patients had mild pain throughout the study, thus possibly compromising study sensitivity. In a subgroup with more intense pain early after arthroscopy, intra-articular morphine 2 mg reduced pain intensity (P < 0.05) and analgesic requirements (P < 0.05) compared with placebo. CONCLUSION: Postoperative analgesic effect of intra-articular morphine was found only in a subgroup of patients with higher pain intensity in the immediate postanaesthetic period. Possible reasons for our overall negative findings include low study sensitivity due to weak pain stimulus, lack of inflammation that may be a prerequisite for peripheral opioid analgesia, and the local anaesthetic, which impedes local inflammatory reaction and expression of peripheral opioid receptors. These factors may also explain the conflicting results in other studies.     

Epidural sufentanil for post-operative pain relief: effects of adrenaline

The analgesic, respiratory and haemodynamic effects of epidural sufentanil 75 micrograms (Group 1) or sufentanil 75 micrograms with adrenaline 75 micrograms (Group 2) were studied in 20 patients following abdominal surgery in a double-blind randomized trial. Pain relief, assessed on a linear analogue scale, sedation, heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR) and arterial carbon dioxide tension (PaCO2) were recorded before, and for 12 h after, injection. Good post-operative pain relief was obtained after 4 min in Group 1 and 6 min in Group 2. All patients in both groups were pain-free after 30 min. Analgesia lasted for 450 +/- 46 min in Group 1 and 690 +/- 92 min in Group 2 (P less than 0.05). Coughing and active movement was possible with little pain for 6 h post-operatively in Group 1 and 7 h in Group 2. The respiratory rate was significantly decreased from 15 min to 1 h after injection in Group 1 compared with Group 2 (P less than 0.05) and in three patients in Group 1 it was necessary to stimulate the patients verbally to maintain adequate respiration. PaCO2 increased significantly in both groups over the first 2 h. The patients in Group 1 showed more marked sedation 1 h after injection. Changes of HR and MAP were similar in both treatment groups. Side-effects were observed more frequently in Group 2, although the differences were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)     

Thoracic epidural clonidine and morphine for postoperative pain relief

This study was undertaken to evaluate the potentiation of the postoperative analgesic effect of thoracic epidural morphine by coadministration of thoracic epidural clonidine in a randomized double-blinded design. Twenty patients underwent radical gastrectomy under combined general anaesthesia (enflurane and nitrous oxide/oxygen) and epidural anaesthesia with local anaesthetics. They received a thoracic epidural bolus injection of either 0.05 mg · kg^?1 morphine plus 3 μg · kg^?1 clonidine (M+C group; n =10) or 0.05 mg · kg^?1 morphine alone, (M group; n = 10) immediately before completion of surgery. All patients received iv morphine via patient-controlled analgesia (PCA) equipment for 24 hr postoperative period, and the PCA iv consumption of morphine was the primary variable of efficacy of the analgesic regimen. In addition, data analyses included mean arterial blood pressure, heart rate, respiratory rate, arterial blood gas measurement, sedation score, and visual analogue pain scale score (VAS). The cumulative number of iv morphine injections via PCA was less in the M+C group than in the M group at each hour for 24 hr postoperative period (P < 0.05), while the numbers of PCA morphine injections per hour beyond nine hours after surgery were higher in the M group than in the M+C group (P < 0.05). Sedation score was higher, and VAS and mean blood pressure were lower in the M+C group only at one hour after surgery compared with the M group. We conclude that the combined single thoracic epidural administration of morphine plus clonidine produces a more potent and longer lasting analgesia than does morphine alone.     

Epidural morphine for postoperative pain relief in children

Epidural morphine for postoperative pain relief is in general use, and has proved to be very efficient in adults. The epidural technique and the use of epidural morphine are much less frequent in children. For 2 years we have prospectively followed 76 children who had epidural morphine for postoperative pain relief after major abdominal surgery. The age distribution was from newborn to 13 years, with a median age of 12 months. It was estimated that 94% of the patients had good analgesia for the first 24 postoperative hours and no other opioids were given. The side effects were few, but one case of respiratory depression was seen and 20% of the children had pruritus. There were four dural punctures and three catheters slipped out accidentally, but otherwise the treatment was continued as long as it was considered necessary (1–11 days). The use of postoperative ventilatory support decreased during the investigation. We observed a change in the sleeping pattern with an increased number of sleep–induced myoclonia during the administration of epidural morphine. In conclusion, the use of epidural morphine in children for postoperative pain relief is very efficient. The minimal effective dose has not been established as yet, but 50 Hg/kg every 8 h, supplemented with small doses of bupivacaine, provides excellent analgesia in the immediate postoperative period after major abdominal surgery. The side effects are few, but the risk of respiratory depression is always present and observation in the intensive care unit or recovery for the first 24 h is strongly recommended.