Tramadol is a weak centrally acting analgesic and it might provide efficacious postoperative pain relief with minimal sedative effects in the use of intravenous patient-controlled analgesia (PCA). Sixty women scheduled to undergo microvascular breast reconstruction under standard general anaesthesia were enrolled in a study on the performance of patient-controlled analgesia with tramadol or morphine with special emphasis on drug- and technique-related side-effects. Seven patients were re-operated within the same day, leaving 25 patients in the tramadol group and 28 in the morphine group for comparison. When postoperative pain occurred, loading doses of either 10mg tramadol or 1mg morphine intravenous increments were administered in a double-blind fashion until the pain control was judged to be satisfactory by the patient. After that the patients received tramadol or morphine by a PCA apparatus (lockout 5 min, tramadol 450 μg kg−1, morphine 45 μg kg−1 bolus). In addition, all patients received 500mg paracetamol rectally, three times a day. The potency ratio of tramadol to morphine was found to be between 8.5 : 1 (loading) and 11 : 1 (PCA). There was neither a significant difference between the groups in the overall satisfaction of the analgesic medication nor in the visual analogue and verbal rate scales for pain. Women in the tramadol group had more nausea and vomiting during the administration of loading doses (P < 0.05) and more patients in the tramadol group (7) than in the morphine group (3)(NS) wanted to discontinue the PCA therapy before the end of the study due to nausea. Sedation or blurred vision prevented the performance of the psychomotor tests in 22 and 32% of the tramadol and morphine patients, respectively. The remaining patients performed similarly in the Digit Symbol Substitution Test. In women receiving intravenous PCA for analgesia after microvascular breast reconstruction tramadol and morphine provided comparable postoperative analgesia with similar sedative effects. However, tramadol was associated with a disturbingly high incidence of nausea and vomiting.

The study compares responders and non-responders to post-operative patient-controlled analgesia (PCA) and evaluates factors that might differ between these two groups in order to identify non-responders during the early post-operative period. A prospective, randomized, double-blinded study design was used. Patients recovering from abdominal surgery were assigned to one of three treatment groups for a study period of 48 h. After titration of an individual loading dose, patients could self-administer 1 mL bolus doses(2 mg of morphine, 20 mg of tramadol or placebo) using a PCA device. Patients responding or not responding to the treatment were identified. In non-responders the escape medication was morphine.There were 96 responders and 65 non-responders. All responders showed similar pain scores, irrespective of the drug they received. Drug consumption of placebo responders was twice as high as that of opioid responders. Pain scores and analgesic consumption of non-responders were significantly higher compared with responders, although those patients received morphine. The loading dose correlated with subsequent analgesic consumption. Altogether, 89.2% of the non-responders were identified after the loading dose. Size of loading dose and pain scores during the first 30 min are useful for assessing the overall response to post-operative pain management. These factors may be valuable for predicting individual pain management.

Prolonged nerve conduction blockade has been proposed to result from the summed effects of charged and neutral local anaesthetics. Thirty-seven patients were randomly allocated to receive intravenous patient-controlled analgesia alone or combined with intercostal blockade (T7–T11) with a mixture of 0.45% bupivacaine and 0.6% phenol for post-cholecystectomy analgesia. Adequacy of pain relief was measured by patient scores on a 10-cm visual analogue scale and by dose–demand ratio, amounts of loading dose and total consumption of morphine and also the duration of patient-controlled analgesia in each group. No differences were found between groups in post-operative scores, dose–demand ratios and loading doses of morphine. However, in the combined treatment group, a significantly lower total consumption of morphine (P<0.05), associated with a shorter duration of patient-controlled analgesia (P<0.02) and a decreased mean number of unsuccessful demands (P<0.001) were recorded. Intercostal blockade with bupivacaine–phenol supplements intravenous patient-controlled analgesia for post-cholecystectomy pain relief.

The present study contrasted the pharmaco-economics and analgesic efficacy of intramuscular (i.m.) opioid treatment with a parenteral disposable patient-controlled analgesia (PCA) system in two groups of 20 female patients (ASA I–II, aged 35–69 years) scheduled for abdominal hysterectomy. The PCA group received a continuous infusion of 1.5 mg h−1 piritramide, a μ-opioid receptor agonist, with incremental doses of 1.5 mg (lock-out interval=15 min). The i.m. group received 0.3 mg kg−1 piritramide i.m. when requested by the patient with a minimum interval of 5 h. Pain intensity, sedation and the functional recovery of the patients were followed for 72 h post-operatively. The sum of pain intensity differences (SPID) was used as a measure of analgesic efficiency. Equipment and drug costs, and the demand on nursing time were recorded over 3 days post-operatively. The costs of PCA and i.m. therapies per patient were used to calculate the cost-benefit (cost of treatment vs. nursing time) and cost-effectiveness (cost of treatment vs. SPID) analyses. Both treatments initially provided comparable analgesia, but PCA was more efficient after 16 h and significantly reduced nursing time for pain treatment (PCA=61±4 min, i.m.=88±5 min; P<0.001). Functional recovery was not different for either treatment. Cost analysis indicated a better cost-benefit ratio for the i.m. treatment (0.35 vs. 1.1 for PCA treatment), but a similar cost-effectiveness for both treatments (PCA=1.9 Belgian Francs (BEF) unit−1 SPID; i.m.=1.7 BEF unit−1 SPID).

Eighty patients were recruited into a double-blind, randomized trial to find the optimal dose of droperidol for addition to the patient-controlled analgesia (PCA) morphine infusate for female patients undergoing gynaecological surgery. A standardized anaesthetic technique was employed. Post-operative analgesia was provided by PCA morphine. Patients were allocated at random into one of four treatment groups receiving with each PCA morphine bolus: (1) droperidol 0.05 mg; (2) droperidol 0.10 mg; (3) droperidol 0.15 mg; and (4) droperidol 0.20 mg, respectively. The incidence of post-operative nausea and vomiting (PONV), requests for rescue anti-emetic medication, and incidence of side effects were recorded. The number of symptom-free patients in each group increased as the droperidol dose increased, but although there was a significant inverse association between the total dose of droperidol received and the severity of PONV (P<0.05), there were no significant differences between individual groups. In each group, patients were significantly less sedated at 24 h compared with 12 h (P<0.01). However, after 24 h, patients in group 4 were significantly more sedated than patients in groups 1 and 2 (P<0.05). There were no significant differences between the groups in terms of the incidence of anxiety or other side effects attributable to droperidol. The present authors suggest that, although the results demonstrate few statistically significant differences between the four groups, a PCA bolus dose of droperidol of 0.10 mg mL−1 appears to provide the optimal balance between anti-emetic efficacy and an acceptable incidence of side effects.

A double-blind, randomized, placebo- and drug-controlled study in which the analgesic efficacy and safety of intravenous (i.v.) tramadol in patients with postoperative pain is reported. One hundred and eighty patients recovering from gynaecological or abdominal surgery were assigned to one of three treatment groups. After titration of an individual loading dose, patients could self-administer tramadol 20 mg, morphine 2 mg or placebo using a patient-controlled analgesia (PCA) device throughout a 48-h period. Criteria of efficacy were a decrease in pain intensity within the first 30 min of at least 20 on a visual analogue scale (VAS) (0 denotes no pain, 100 worst pain imaginable) and satisfactory analgesia in the patient's opinion during the study period. Patients treated with tramadol, morphine and placebo were assessed as responders at 66.7%, 75.0% and 18.3% (P < 0.0001). VAS after the initial bolus were 39.2 ± 22.1, 35.9 ± 21.6 and 50.0±24.2 (P = 0.002), the initial loading dose amounted to tramadol 144.9 ± 51.2 mg, morphine 12.3 ± .1 mg and placebo 17.2 ± 4.9 mL. No serious opioid-related adverse events occurred in the patients given tramadol while two patients given morphine developed an impaired respiratory rate and a decreased oxygen saturation to 80% or less. Tramadol proved to be efficacious for PCA treatment of post-operative pain following gynaecological and abdominal surgery.

Sufentanil or a sufentanil-clonidine combination was evaluated to determine whether the basal rate in patient-controlled epidural analgesia (PCEA) might affect the daily consumption, quality of analgesia or incidence of side effects. Following Caesarean section delivery, 60 patients were randomly assigned to receive one of the four following PCA regimens (15 patients per group) for the relief of post-operative pain by the epidural route: sufentanil 2μg mL−1 in 0.9% NaCl, demand dose 5μg i.e. 2.5mL, (group S+ with, group S without an infusion at 2.5mL hr−1) or sufentanil 2μg mL−1 + clonidine 3μg mL−1, demand dose 5μg sufentanil + 7.5μg clonidine i.e. 2.5mL (group SC+ with and SC without an infusion of 2.5ml hr−1). The other PCA settings (Bard I PCA pump) were a lock out interval of 10 min and a 1h limit of 20μg sufentanil and 30μg clonidine i.e. 10mL. The parameters measured were the analgesic drug consumption and number of dose demands during the first 24h, pain scores at 6h intervals, side effects and quality of sleep. The concurrent infusion increased the dose requirements regardless of the content of the syringe. Consumption of sufentanil was the highest in those patients receiving the plain solution with a basal infusion. Clonidine addition reduced the dose requirements but only significantly in those receiving the background infusion. Patients treated with the mixture tended to reach lower pain scores than those receiving sufentanil only without basal rate. Patients receiving the mixture with basal rate requested significantly fewer additional demands compared with the three other groups, but this did not influence the quality of sleep. Since side effects were more frequently registered in the patients in this group, it was concluded that the optimum regimen was the sufentanil-clonidine combination but with deletion of the basal rate.