Postoperative Pain Management in Coronary Artery Bypass Grafting: An Integrative Review

PURPOSE

To identify pharmacological and nonpharmacological interventions adopted for pain relief in the postoperative period of coronary artery bypass graft surgery.

DESIGN

Integrative review.

METHODS

Studies published in English, Spanish, and Portuguese from January 2010 to December 2019 in Cumulative Index to Nursing and Allied Health Literature (CINAHL), Latin American and Caribbean Literature on Health Science, PubMed, and Web of Science. Two hundred studies were identified and eleven were included. Methodological analysis was performed using the Medical Education Research Study Quality Instrument.

FINDINGS

The studies found were organized into three thematic categories: pharmacological interventions (methadone, morphine, lidocaine gel, remifentanil, sufentanil, and nefopam), nonpharmacological interventions (low-level laser therapy, light-emitting diode, Class IV laser, and transcutaneous nerve stimulation) and anesthetic techniques (dexmedetomidine, ultrasound-guided pectoral nerve block, high thoracic epidural analgesia, and perioperative parasternal block with levobupivacaine).

CONCLUSIONS

A greater tendency to use drug strategies for postoperative pain relief was identified. The drugs used demonstrated efficacy and safety in the treatment of pain, with the exception of nefopam, which showed little benefit in this population. Nonpharmacological interventions, used as adjuvants to drug treatment, were shown to be safe, effective, and well tolerated by the patients.

Antinociceptive effects of nefopam activating descending serotonergic modulation via 5-HT2 receptors in the nucleus raphe magnus

BACKGROUND

Nefopam is a centrally acting antinociceptive drug; however, the underlying mechanisms are not fully understood. This study investigated the supraspinal mechanisms of nefopam.

METHODS

The effects of intraperitoneally administered nefopam were assessed in rats using the formalin test, and the mechanisms were investigated by intrathecal or intra-nucleus raphe magnus (NRM) pre-treatment with the serotonin (5-HT) receptor antagonist or 5-HT2 receptor antagonist. The change in extracellular 5-HT levels was measured by spinal cord microdialysis.

RESULTS

Intraperitoneally administered nefopam showed antinociceptive effects in the rat formalin test, which were reversed by intrathecal pre-treatment with 5-HT receptor antagonist dihydroergocristine. Microdialysis study revealed that systemic nefopam significantly increased 5-HT level in the spinal dorsal horn. Pretreatment of cinanserin, a 5-HT2 receptor antagonist, into the NRM blocked the antinociceptive effects of intraperitoneally delivered nefopam. Direct injection of nefopam into the NRM mimicked the effects of systemic nefopam, and this effect was reversed by intra-NRM cinanserin pre-treatment. The increase in spinal level of 5-HT by systemic nefopam was attenuated by intra-NRM cinanserin pre-treatment.

CONCLUSION

The antinociceptive effects of systemically administered nefopam are mediated by 5-HT2 receptors in the NRM, which recruit the descending serotonergic fibres to increase the release of 5-HT into the spinal dorsal horn.

SIGNIFICANCE

This study revealed supraspinal mechanisms of nefopam-produced analgesia mediated by 5-HT2 receptors in the NRM recruiting the descending serotonergic fibres to increase the release of 5-HT into the spinal dorsal horn. These observations support a potential role for nefopam in multimodal analgesia based on its distinct mechanisms of action that are not shared by the other analgesics.

The effect of the addition of nefopam to intraoperative ketoprofen and acetaminophen on postoperative morphine requirements after laparoscopic cholecystectomy: a randomized controlled trial

BACKGROUND

Few studies investigated the use of nefopam for pain control after laparoscopic cholecystectomy in the context of multimodal analgesia. The aim of this study was to evaluate the effect of adding nefopam to ketoprofen and acetaminophen given before the end of laparoscopic cholecystectomy.

METHODS

In this double-blind, controlled study, 90 patients undergoing laparoscopic cholecystectomy during sevoflurane-dexmedetomidine-based anesthesia were randomized to receive either ketoprofen and acetaminophen or nefopam, ketoprofen, and acetaminophen for postoperative pain control before the end of surgery. The primary outcome was total morphine consumption in the Postanesthesia Care Unit (PACU).

RESULTS

PACU morphine consumption was significantly lower in the experimental group compared to the control group (0.9±1.8 mg vs. 2.3±2.4 mg, respectively; P=0.004, Cohen's d=0.63). In the experimental group, a smaller proportion of patients received morphine in PACU (24% vs. 60%, respectively; P=0.001), morphine during the first 24 hours after surgery (47% vs. 77%, respectively; P=0.004), and acetaminophen on the floor (76% vs. 93%, respectively; P=0.039) compared with the control group. The average pain score during PACU stay was also significantly lower in the experimental group (1.7±2.0 vs. 2.7±2.0, P=0.01). Median time to first morphine requirement (44.0 minutes, 95% CI [(31.96 to, 52.21)] was shorter in the control group than in the experimental group (higher than the 90 minutes-last time point taken in PACU).

CONCLUSIONS

Adding nefopam to ketoprofen and acetaminophen before the end of laparoscopic cholecystectomy provides a reduction in morphine consumption with superior analgesia in PACU.

Postoperative analgesia of intraoperative nefopam in patients undergoing anterior cervical spine surgery: A prospective randomized controlled trial

BACKGROUND

Nefopam is a non-opioid, non-nonsteroidal anti-imflammatory drug, analgesic drug that inhibits the reuptake of serotonin, norepinephrine, and dopamine. It is widely used as an adjuvant for pain. This study investigated whether the intraoperative, intravenous infusion of nefopam (20 mg) reduces postoperative morphine consumption, pain scores, and alleviates neuropathic pain in patients undergoing cervical spine surgery.

METHODS

A prospective, paralleled design, randomized study was conducted on 50 patients (aged 18-75 years) in a university-based hospital. The patients were assigned to an intervention or a control group (25 patients in each). The intervention group received a 1-hour infusion of nefopam (20 mg) before the end of surgery. The control group received normal saline (NSS). The outcome measures were morphine consumption during the first 24 postoperative hours, numerical rating scale (NRS) pain scores, and scores for the Thai version of the Neuropathic Pain Symptom Inventory (NPSI-T) in patients with neuropathic pain and adverse drug reactions. The NPSI-T scores were assessed on the preoperative day, postoperative day 1, 3, 15, and 30. The outcome assessors were blinded to group allocation.

RESULTS

Fifty patients were analyzed. During the first 24 postoperative hours, morphine consumption was 8 mg (nefopam) and 12 mg (NSS; P = .130). The intervention and control groups demonstrated no significant differences in the median NRS scores or total NPSI-T scores or adverse drug reactions.

CONCLUSIONS

A single, intraoperative infusion of 20 mg of nefopam did not significantly reduce postoperative (24 hours) morphine consumption in patients undergoing anterior cervical spine surgery.

Effect of Continuous Infusion of Intravenous Nefopam on Postoperative Opioid Consumption After Video-assisted Thoracic Surgery: A Double-blind Randomized Controlled Trial

BACKGROUND

Although nefopam has been reported to have opioid-sparing and analgesic effects in postsurgical patients, its effectiveness in video-assisted thoracoscopic surgery (VATS) is unknown.

OBJECTIVES

This study aimed to investigate the opioid-sparing and analgesic effects of perioperative nefopam infusion for lung resection.

STUDY DESIGN

Double-blinded randomized controlled trial.

SETTING

Operating room, postoperative recovery room, and ward at a single tertiary university hospital.

METHODS

Ninety patients scheduled for elective VATS for lung resection were randomized to either the nefopam (group N) or control group (group C). Group N received 20 mg nefopam over 30 minutes immediately after the induction of anesthesia. Nefopam was administered continuously for 24 hours postoperative, using a dual-channel elastomeric infusion pump combined with fentanyl-based intravenous patient-controlled analgesia. Group C received the same volume of normal saline as nefopam solution administered in the same manner. The primary outcome measure was fentanyl consumption for the first postoperative 24 hours. The secondary outcome measures were the cumulative fentanyl consumption during the first postoperative 48 hours, pain intensity at rest and during coughing evaluated using an 11-point numeric rating scale, quality of recovery at postoperative time points 24 hours and 48 hours, and the occurrence of analgesic-related side effects during the first postoperative 24 hours and postoperative 24 to 48 hour period. Variables related to chronic postsurgical pain (CPSP) were also investigated by telephone interviews with patients at 3 months postoperative. This prospective randomized trial was approved by the appropriate institutional review board and was registered in the ClinicalTrials.gov registry.

RESULTS

A total of 83 patients were enrolled. Group N showed significantly lower fentanyl consumption during the first postoperative 24 hours and 48 hours (24 hours: median difference: -270 µg [95%CI, -400 to -150 µg], P < 0.001); 48 hours: median difference: -365 µg [95% CI: -610 to -140 µg], P < 0.001). Group N also showed a significantly lower pain score during coughing at 24 hours postoperative (median difference, -1 [corrected 95% CI: -2.5 to 0], adjusted P = 0.040). However, there were no significant between-group differences in the postoperative quality of recovery, occurrence of analgesic-related side effects, length of hospital stay, and occurrence of CPSP.

LIMITATIONS

Despite the significant opioid-sparing effect of perioperative nefopam infusion, it would have been difficult to observe significant improvements in other postoperative outcomes owing to the modest sample size.

CONCLUSION

Perioperative nefopam infusion using a dual-channel elastomeric infusion pump has a significant opioid-sparing effect in patients undergoing VATS for lung resection. Therefore, it could be a feasible option for multimodal analgesia in these patients.

Different interventions for preventing postoperative catheter-related bladder discomfort: a systematic review and meta-analysis

OBJECTIVE

Catheter-related bladder discomfort (CRBD) is a common complication of intraoperative urinary catheterization. Various studies have evaluated the efficacy of different interventions in postoperative CRBD. The present review was performed to assess the efficacy of these interventions.

METHODS

PubMed, Embase, and CENTRAL (Cochrane Central Register of Controlled Trials) databases were systematically searched to identify randomized controlled trials (RCTs) investigating the efficacy of different drugs for the prevention of postoperative CRBD. This review evaluated the incidence and severity of CRBD after different interventions at 0, 1, 2, and 6 h postoperatively.

RESULTS

Forty-five studies including 31 different drugs were analyzed. Eleven drugs were investigated in more than two RCTs, of which dexmedetomidine, gabapentin, tolterodine, tramadol, ketamine, nefopam, oxybutynin, pregabalin, and pudendal nerve block (PNB) generally showed significantly higher efficacy than controls postoperatively. Solifenacin only showed significant efficacy compared with the control at 0 h, and intravenous lidocaine only showed significant efficacy compared with the control at 6 h. There were insufficient trials to draw conclusions regarding atropine, butylscopolamine, chlorpheniramine, clonidine, darifenacin, diphenhydramine, glycopyrrolate, intravesical bupivacaine, ketamine-haloperidol, pethidine-haloperidol, ketorolac, lidocaine-prilocaine cream, magnesium, hyoscine n-butyl bromide, oxycodone, paracetamol, parecoxib, trospium, resiniferatoxin, or amikacin. However, all but pethidine-haloperidol and chlorpheniramine showed some efficacy at various time points compared with controls.

CONCLUSION

This review suggests that dexmedetomidine, gabapentin, tolterodine, tramadol, ketamine, nefopam, oxybutynin, pregabalin, and PNB are effective in preventing postoperative CRBD. Considering the efficacy and adverse effects of all drugs, dexmedetomidine and gabapentin were ranked best.

Nefopam prescribing preferences in French hospitals: results of a survey

Introduction

nefopam is a non-opioid, centrally-acting analgesic, frequently prescribed in France for acute pain and postoperatively. Only intravenous (IV) formulation is available, however the off-label oral use is frequent in surgical and medical patients. There is no data on the actual in-hospital prescription preferences in French physicians regarding nefopam. We wish to identify nefopam prescription habits for acute and chronic pain among hospital physicians.

Methods

an online survey was sent to physicians via professional emails. Frequency of prescription, indication, preferred and prescribed administration route, dose regimen, and personal perception of the nefopam tolerance and efficiency were examined.

Results

a total of 527 responses were analysed. Nefopam was mostly prescribed by senior hospital physicians, for acute pain, orally (85%), 20 mg/6h with 120 mg maximal daily dose. For chronic pain, the oral administration was more frequent. More than half of prescribers considered the efficacy of the oral route was similar to intravenous, and better tolerated compared to intravenous administration. Forty-eight percent of responders would change their prescription attitude in case of oral route approval of nefopam.

Conclusion

oral prescription of intravenous formulation of nefopam is frequent, especially for acute pain, and has the same dose and regimen pattern as for intravenous route. Prescribers consider oral nefopam efficient and safe for patients. Regulatory actions regarding the oral nefopam prescription authorization and duration of such prescription are needed.

Analgesic efficacy of intravenous nefopam after spine surgery: a randomized, double-blind, placebo-controlled trial

Background: The incidence of moderate to severe pain is high among patients undergoing spinal surgery. Nefopam can be used as an adjuvant analgesic postoperatively after spine surgery. The study aimed to assess the analgesic efficacy and side effects of nefopam on 24-hour postoperative morphine consumption after spine surgery. Methods: The study is a randomized, double-blinded, placebo-controlled trial. A total of 96 patients were randomized into 4 treatment groups, 24 each. In group 1, patients received normal saline before surgical incision and before the end of surgery. In group 2, patients received 30 mg nefopam before surgical incision and normal saline before the end of surgery. In group 3, patients received normal saline before surgical incision and 30 mg of nefopam before the end of surgery. In group 4, patients received 30 mg of nefopam in both timings. Patient-controlled analgesia morphine was used for the postoperative period. Outcomes were to determine 24-hour morphine consumption and incidence of side effects.  Results: Of 96 patients enrolled, 21 in placebo-placebo, 22 in nefopam-placebo, 22 in placebo-nefopam and 21 in nefopam-nefopam groups completed the study.  Analysis of the Kruskal-Wallis test on the intention-to-treat basis shows no significant difference in 24-hour postoperative morphine consumption between four groups, which were 18 [IQR 13.5-29], 20 [IQR 11-28.3], 17 [IQR 11.5-28.5], 13 [IQR 8.5-18.5] mg., respectively (p = 0.223). Incidence of side effects, including tachycardia, sedation, sweating and nausea/ vomiting, did not differ. Conclusions: Adding perioperative nefopam to opioid analgesic does not improve analgesic efficacy in patients who underwent spine surgery. Registration: Thai Clinical Trials Registry ID TCTR20171115001; registered on 15 November 2017.

Analgesic efficacy of intravenous nefopam after spine surgery: a randomized, double-blind, placebo-controlled trial

Background: The incidence of moderate to severe pain is high among patients undergoing spinal surgery. Nefopam can be used as an adjuvant analgesic postoperatively after spine surgery. The study aimed to assess the analgesic efficacy and side effects of nefopam on 24-hour postoperative morphine consumption after spine surgery. Methods: The study is a randomized, double-blinded, placebo-controlled trial. A total of 96 patients were randomized into 4 treatment groups, 24 each. In group 1, patients received normal saline before surgical incision and before the end of surgery. In group 2, patients received 30 mg nefopam before surgical incision and normal saline before the end of surgery. In group 3, patients received normal saline before surgical incision and 30 mg of nefopam before the end of surgery. In group 4, patients received 30 mg of nefopam in both timings. Patient-controlled analgesia morphine was used for the postoperative period. Outcomes were to determine 24-hour morphine consumption and incidence of side effects.  Results: Of 96 patients enrolled, 21 in placebo-placebo, 22 in nefopam-placebo, 22 in placebo-nefopam and 21 in nefopam-nefopam groups completed the study. Analysis of the Kruskal-Wallis test shows no significant difference in 24-hour postoperative morphine consumption between four groups, which were 18 [IQR 13.5-29], 20 [IQR 11-28.3], 17 [IQR 11.5-28.5], 13 [IQR 8.5-18.5] mg., respectively (p = 0.223).  Incidence of side effects, including tachycardia, sedation, sweating and nausea/ vomiting, did not differ. Conclusions: Adding perioperative nefopam to opioid analgesic does not improve analgesic efficacy in patients who underwent spine surgery. Registration: Thai Clinical Trials Registry ID TCTR20171115001; registered on 15 November 2017.

Effects of nefopam with fentanyl in intravenous patient-controlled analgesia after arthroscopic orthopedic surgery: a prospective double-blind randomized trial

Background/aim: We performed this prospective randomized double-blind study to compare the effects of nefopam versus ketorolac in intravenous fentanyl-based patient-controlled analgesia (PCA) after shoulder arthroscopic orthopedic surgery. Materials and methods: Ninety-two patients were randomly divided into two groups to receive intravenous PCA. Patients were assigned to either the nefopam group (nefopam 120 mg and fentanyl 20 µg/kg) or the ketorolac group (ketorolac 2 mg/kg and fentanyl 20 µg/kg). Pain was assessed on a visual analogue scale (VAS) and a numeric rating scale (NRS). Additionally, patient satisfaction, adverse events, and vital signs were monitored. Results: There were no significant differences in VAS score (P = 0.48) or NRS score (P = 0.15) between the two groups. Similarly, patient satisfaction did not differ between the two groups [8.5(0.8) vs. 8.2(1.0), P = 0.14]. There were no statistically significant differences in the incidence of nausea (P = 0.72), vomiting (P = 0.46), urinary retention (P = 0.82), sweating (P = 0.49), or dizziness (P = 0.45) between the two groups. Likewise, there were no differences in heart rate [78.2(7.7) vs. 75.2(6.5), P = 0.18] or SpO2 [98.4(1.8) vs. 98.5(1.9), P = 0.83]. Conclusion: Nefopam is an appropriate alternative for co-administration with fentanyl-based PCA in patients who have difficulty using nonsteroidal antiinflammatory drugs.

Preventive Analgesic Efficacy of Nefopam in Acute and Chronic Pain After Breast Cancer Surgery: A Prospective, Double-Blind, and Randomized Trial

Breast cancer surgery is known to cause severe acute postoperative pain, which can persist for a long time. We administered nefopam preventively to patients undergoing lumpectomy with axillary lymph node dissection or sentinel lymph node biopsy, and evaluated its efficacy on acute and chronic postoperative pain.Enrolled patients were assigned to the nefopam (n = 41) or the control (n = 42) group. Before initiating the operation, 20 mg of nefopam was given to the patients of the nefopam group, and normal saline was used in the control group. Ketorolac was given at the end of surgery, and meloxicam was prescribed in the postoperative period to all patients in both groups. Pain was assessed using a numerical rating scale (NRS), and the rescue analgesic drug was given when the NRS was >5. Implementation of postoperative chemotherapy, radiotherapy (RT), or hormone therapy was evaluated.The NRS of postoperative pain was significantly lower in the nefopam than in the control group in the postanesthetic care unit (4.5 ± 2.2 vs 5.7 ± 1.5, respectively; P = 0.01), at postoperative 6 h (3.0 ± 1.6 vs 4.5 ± 1.3, respectively; P < 0.001), and at postoperative 24 h (3.1 ± 1.1 vs 3.8 ± 1.5, respectively; P = 0.01) with reduced use of rescue analgesic drugs. Significantly fewer patients suffered from chronic postoperative pain in the nefopam than in the control group at postoperative 3 months (36.6% vs 59.5%, P = 0.04). Considering only the cohort without postoperative adjuvant RT, the difference in the proportion of patients reporting chronic pain increased (23.5% in the nefopam group vs 61.5% in the control group, P = 0.04).Preventive nefopam was helpful in reducing the acute postoperative pain, with reduced use of rescue analgesic drugs, and it contributed to reduced occurrence of chronic pain at postoperative 3 months after breast cancer surgery.

[Thrombocytopenia and postoperative analgesia]

OBJECTIVE

To develop effective and safe measures of postoperative multimodal analgesia (optimizing the use of narcotic analgesics) in surgical treatment of hematological patients with thrombocytopenia.

DESIGN

A pilot and prospective comparative controlled study.

METHODS

We studied 27 patients with acquired thrombocytopenia who underwent laparoscopic splenectomy. Three schemes of anesthesia were used: 1) Nefopam 20 mg/day + trimeperidin (n = 7); 2) Paracetamol 4 g/day + trimeperidin (n = 10); 3) paracetamol + trimeperidin + glucocorticosteroids (GC) (through treatment of the underlying disease) (n = 10). Analgesic properties and effect of each scheme were assessed according to a rating scale of pain NRS (10 points) and VAS (100 points) studied. Additionally we evaluated the effect of nefopam and paracetamol on the functional properties of platelets and hemostasis, platelet levels while monitoring and indicators of thromboelastogram (TEG).

RESULTS

Application of paracetamol + trimeperidin accompanied with effectively reducing of postoperative pain (less than 5 points on the NRS). The level of postoperative pain was lower in patients who were treated with corticosteroids within the therapy of the underlying disease before surgery and who continued to receive it in postoperative period (2-3 points NRS). Nefopam use in the perioperative period is not only inferior to the analgesic effect of paracetamol, but also causes frequent side effects. Consumption of narcotic analgesic--trimeperidin when applying nefopam averaged 43 mg/day, the appointment of paracetamol--28 mg/day, using a combination of paracetamol + GC--20 mg/day. Thus, GC within the underlying disease treatment substantially reduces the need for opioid analgesics. A monitoring of the number of platelets and TEG did not shows negative effect of paracetamol and nefopam on platelet and plasma hemostasis.

CONCLUSIONS

Nefopam and paracetamol may be used in patients with thrombocytopenia, as do not affect the hemostasis and platelet count. Application of postoperative analgesia scheme paracetamol + trimeperidin in patients receiving corticosteroids provides the maximum reduction of pain with the least consumption of narcotic analgesics.

[Postoperative analgesia with nefopam and non-steroidal anti-inflammatory drugs in patients after surgery for tumors of head and neck]

MATERIALS AND METHODS

83 adult patients included in the study were divided into two groups. Patients of the group-1 (n-49) had medium level of pain after cancer head and neck surgery. Patients of the group-2 (n-34) had severe pain. Three first postoperative days their post-operative multimodal analgesia started with tenoxycam 20 mg i.m. after induction of anesthesia, then every 24 hour (58 patients). 25 patients got ketoprofen 100 mg i.m. every 8-12 hours instead of tenoxycam. All patients had nefopam 30 mg i.m. 30 min prior the end of surgery procedure, and every 8 hours afterwards. 7 patients of the group-1 had more than 4 pain scores (day 1), 4 patients--at the day 2. They received tramadol or paracetamol additionally. 7 patients (group-2) also had up to 5 pain scores on the day 1, 5 patients had 4 pain scores on the day 2, and 3 patients 4 pain scores on the day 3. All that patients received additional analgesia with tramadol or trimeperidine once a day. 8.4% of patients suffered from adverse reactions (tachycardia, PONV and sweating).

CONCLUSION

This method of multimodal postoperative analgesia is very simple and fairly efficient.

[Ketoprophen and nefopam combination for postoperative analgesia with minimal use of narcotic analgesics in cardio-surgical patients]

4 combinations of analgesia were studied: 1) Nefopam and patient-controlled analgesia (PCA) with Trimeperidine; 2) Ketoprofen (100 microg each 12 hours intramuscular) and PCA with Trimeperidine; 3) Nefopam, Ketoprofen and PCA with Trimeperidine; 4) PCA with Trimeperidine as monotherapy in early postoperative period in cardio-surgical patients. 80 patients (age from 40 to 70) were divided into 4 groups, 20 patients in each group. Administration of Nefopam and Ketoprofen before extubation reduced the intensity of pain syndrome (in average on 90%) and promoted the early stirring up of patients. Combination of Nefopam and Ketoprofen provided the most expressed analgesic and opioids-saving effects. In this group average amount of Trimeperidine per 24 hours was 14.7 microg that was 4.9 times less than in group of PCA with Trimeperidine as monotherapy. Dynamics of maximal inspiratory capacity of the lungs in the first three groups was better than in group of PCA with Trimeperidine as monotherapy beginning from 6th hour of study. In common undesirable effects was connected with Trimeperidine administration and depended on its dose. The frequency of nausea, vomit, dizziness and weakness was authentically higher in the group of PCA with Trimeperidine as monotherapy than in other groups.

[The use of central acting analgesic nefopam in postoperative analgesia in cardiac surgery patients]

A prospective, randomized, comparative study was conducted. 3 analgesia protocols were used: 1) patient controlled analgesia (PCA) with trimeperidine in combination with a nefopam constant infusion; 2) PCA with trimeperidine in combination with a nefopam bolus; 3) PCA with trimeperidine separately during early postoperative period in cardiac surgery patients. The study included 60 patients agedf rom 40 to 65 years of age (20 patients in each group). The analgesia efficacy was evaluated with a 5-point verbal rating scale (VRS) for pain intensity and inspiratory lung capacity (ILC), measured with incentive spirometer. The safety of nefopam during early postoperative period in cardiac surgery patients was shown. The combination of nefopam and trimeperidine led to a more pronounced analgetic effect. Trimeperidine consumption was significantly lower in nefopam groups than in the group of isolated PCA. Wholly adverse effects were associated with trimeperidine and were dose-related The incidence of nausea, vomiting, dizziness, weakness, bowel paresis was significantly higher in isolated PCA group than in the other two groups.

Median effective dose (ED50) of paracetamol and nefopam for postoperative pain: isobolographic analysis of their antinociceptive interaction

BACKGROUND

The analgesic efficacy of nefopam and of paracetamol has been shown in the postoperative period after mild- and moderate-pain surgery. The aim of this study was to define the median effective analgesic doses of each drug and of their combination, in order to determine the nature of their interaction.

METHODS

Ninety adult patients scheduled to undergo tonsillectomy under general anesthesia were enrolled in one out of three groups: nefopam group, or paracetamol group, or nefopam-paracetamol group. The median effective dose for each drug and also for their combination was defined using an up-and-down sequential allocation technique. The analgesic interaction of their combination was assessed using an isobolographic analysis.

RESULTS

The median effective analgesic dose (median value and 95% confidence interval) of nefopam and paracetamol were 21.7 mg (21.1-22.3 mg) and 628 mg (600-656 mg), respectively. The median effective analgesic doses of the combination were 8.9 mg (8.7-9.1 mg) for nefopam and 265 mg (256-274 mg) for paracetamol. The isobolographic analysis demonstrated a supra-additive interaction of the two drugs.

CONCLUSION

The combination of nefopam and paracetamol produces effective analgesia with a synergistic interaction.

Efficacy and safety of neuromodulators in inflammatory arthritis: a Cochrane systematic review

OBJECTIVE

To determine the efficacy and safety of neuromodulators for pain management in patients with inflammatory arthritis.

METHODS

A Cochrane systematic review was performed as part of the 3e Initiative on pain management in inflammatory arthritis. We searched Medline, Embase, and Cochrane Central for studies to November 2010, and American College of Rheumatology/European League Against Rheumatism meeting abstracts published in 2008-2009. Studies were included if they were randomized or quasirandomized controlled trials that compared any neuromodulator (excluding cannabis) to another therapy (active or placebo, including nonpharmacological therapies) for pain in patients with RA, psoriatic arthritis, ankylosing spondylitis, or spondyloarthritis. Primary outcomes of interest were patient-reported pain relief of 30% or greater and withdrawals due to adverse events. Two authors independently extracted data and assessed methodological quality. A risk of bias assessment was performed using the methods recommended by the Cochrane Collaboration.

RESULTS

Three trials, all in RA and all at high risk of bias, were included in this review. Two placebo-controlled trials evaluated nefopam (52 participants) and one placebo-controlled trial evaluated topical capsaicin 0.025% (31 participants). Pooled analysis showed a significant reduction in pain levels favoring nefopam over placebo after 2 weeks [weighted mean difference -21.2, 95% CI -35.6 to -6.7; number needed to treat (NNT) 2, 95% CI 1.4 to 9.5]. However, nefopam was associated with significantly more adverse events (RR 4.1, 95% CI 1.6 to 10.7; number needed to harm 9, 95% CI 2 to 367), predominantly nausea and sweating. In one trial, capsaicin reduced pain more than placebo at 1 and 2 weeks (MD -23.8, 95% CI -44.8 to -2.8; NNT 3, 95% CI 2-47, and -34.4, 95% CI -54.7 to -14.14; NNT 2, 95% CI 1.4 to 6, respectively). Of those who received capsaicin, 44% developed burning at the site of application and 2% withdrew as a result.

CONCLUSION

Based on 3 small trials, which were all at high risk of bias, there is weak evidence that nefopam and capsaicin are superior to placebo in reducing pain in patients with RA, but both are associated with a significant side effect profile. There are no available data for other types of IA or for newer agents such as gabapentin or pregabalin.

Neuromodulators for pain management in rheumatoid arthritis

BACKGROUND

Pain management is a high priority for patients with rheumatoid arthritis (RA). Despite deficiencies in research data, neuromodulators have gained widespread clinical acceptance as adjuvants in the management of patients with chronic musculoskeletal pain.

OBJECTIVES

The aim of this review was to determine the efficacy and safety of neuromodulators in pain management in patients with RA. Neuromodulators included in this review were anticonvulsants (gabapentin, pregabalin, phenytoin, sodium valproate, lamotrigine, carbamazepine, levetiracetam, oxcarbazepine, tiagabine and topiramate), ketamine, bupropion, methylphenidate, nefopam, capsaicin and the cannabinoids.

SEARCH METHODS

We performed a computer-assisted search of the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, 4th quarter), MEDLINE (1950 to week 1 November 2010), EMBASE (Week 44, 2010) and PsycINFO (1806 to week 2 November 2010). We also searched the 2008 and 2009 American College of Rheumatology (ACR) and European League against Rheumatism (EULAR) conference abstracts and performed a handsearch of reference lists of articles.

SELECTION CRITERIA

We included randomised controlled trials which compared any neuromodulator to another therapy (active or placebo, including non-pharmacological therapies) in adult patients with RA that had at least one clinically relevant outcome measure.

DATA COLLECTION AND ANALYSIS

Two blinded review authors independently extracted data and assessed the risk of bias in the trials. Meta-analyses were used to examine the efficacy of a neuromodulator on pain, depression and function as well as their safety.

MAIN RESULTS

Four trials with high risk of bias were included in this review. Two trials evaluated oral nefopam (52 participants) and one trial each evaluated topical capsaicin (31 participants) and oromucosal cannabis (58 participants).The pooled analyses identified a significant reduction in pain levels favouring nefopam over placebo (weighted mean difference (WMD) -21.16, 95% CI -35.61 to -6.71; number needed to treat (NNT) 2, 95% CI 1.4 to 9.5) after two weeks. There were insufficient data to assess withdrawals due to adverse events. Nefopam was associated with significantly more adverse events (RR 4.11, 95% CI 1.58 to 10.69; NNTH 9, 95% CI 2 to 367), which were predominantly nausea and sweating.In a mixed population trial, qualitative analysis of patients with RA showed a significantly greater reduction in pain favouring topical capsaicin over placebo at one and two weeks (MD -23.80, 95% CI -44.81 to -2.79; NNT 3, 95% CI 2 to 47; MD -34.40, 95% CI -54.66 to -14.14; NNT 2, 95% CI 1.4 to 6 respectively). No separate safety data were available for patients with RA, however 44% of patients developed burning at the site of application and 2% withdrew because of this.One small, low quality trial assessed oromucosal cannabis against placebo and found a small, significant difference favouring cannabis in the verbal rating score 'pain at present' (MD -0.72, 95% CI -1.31 to -0.13) after five weeks. Patients receiving cannabis were significantly more likely to suffer an adverse event (risk ratio (RR) 1.82, 95% CI 1.10 to 3.00; NNTH 3, 95% CI 3 to 13). These were most commonly dizziness (26%), dry mouth (13%) and light headedness (10%).

AUTHORS' CONCLUSIONS

There is currently weak evidence that oral nefopam, topical capsaicin and oromucosal cannabis are all superior to placebo in reducing pain in patients with RA. However, each agent is associated with a significant side effect profile. The confidence in our estimates is not strong given the difficulties with blinding, the small numbers of participants evaluated and the lack of adverse event data. In some patients, however, even a small degree of pain relief may be considered worthwhile. Until further research is available, given the relatively mild nature of the adverse events, capsaicin could be considered as an add-on therapy for patients with persistent local pain and inadequate response or intolerance to other treatments. Oral nefopam and oromucosal cannabis have more significant side effect profiles however and the potential harms seem to outweigh any modest benefit achieved.

The Effect of Nefopam on Morphine Overconsumption Induced by Large-Dose Remifentanil During Propofol Anesthesia for Major Abdominal Surgery

Opioids may activate pain facilitatory systems opposing analgesia. We investigated whether large-dose remifentanil given during IV anesthesia caused postoperative morphine overconsumption and whether nefopam (a centrally acting analgesic) could reduce this. Sixty patients scheduled for abdominal surgery were included in this prospective, randomized study. The first 30 patients received either small-dose (Group S: 3 ng/mL) or large-dose (Group L: 8 ng/mL) remifentanil administrated by a target-controlled infusion during propofol anesthesia. Before skin closure, patients received morphine 0.15 mg/kg. Another 30 patients also received nefopam 20 mg intraoperatively. Postoperative pain was controlled by titration of morphine, followed by patient-controlled morphine analgesia (PCA). Morphine was requested earlier in Group L than in Group S (10 [1-63] min versus 37 [5-90] min, median [range]; P < 0.002). The dose of morphine by titration was larger in Group L than in Group S (0.28 [0.04-0.38] mg/kg versus 0.16 [0.03-0.41] mg/kg; P < 0.05). PCA morphine consumption and pain scores were similar. There were no differences between the nefopam groups in the time to first morphine request or in the dose of morphine by titration. Postoperative morphine overconsumption occurred after large-dose remifentanil and propofol anesthesia during the early postoperative period. Pretreatment with nefopam could be useful to prevent pain sensitization induced by opioids.

Nefopam and ketamine comparably enhance postoperative analgesia

Opioids alone sometimes provide insufficient postoperative analgesia. Coadministration of drugs may reduce opioid use and improve opioid efficacy. We therefore tested the hypothesis that the administration of ketamine or nefopam to postoperative patients with pain only partly alleviated by morphine reduces the amount of subsequent opioid necessary to produce adequate analgesia. Patients (n=77) recovering from major surgery were given up to 9 mg of IV morphine. Those who still had pain were randomly assigned to blinded administration of 1) isotonic saline (control group; n=21), 2) ketamine 10 mg (ketamine group; n=22), or 3) nefopam 20 mg (nefopam group; n=22). Three-milligram morphine boluses were subsequently given at 5-min intervals until adequate analgesia was obtained, until 60 min elapsed after the beginning of study drug administration, or until ventilation became insufficient (respiratory rate <10 breaths/min or saturation by pulse oximetry <95%). Supplemental morphine (i.e., after test drug administration) requirements were significantly more in the control group (mean +/- sd; 17 +/- 10 mg) than in the nefopam (10 +/- 5 mg; P <0.005) or ketamine (9 +/- 5 mg; P <0.001) groups. Morphine titration was successful in all ketamine and nefopam patients but failed in four control patients (two because of respiratory toxicity and two because of persistent pain). Tachycardia and profuse sweating were more frequent in patients given nefopam, and sedation was more intense with ketamine; however, the incidence of other potential complications did not differ among groups.

Effets analgésiques de l'administration intraveineuse continue de néfopam après chirurgie urologique

OBJECTIVES

To evaluate the efficacy of continuous infusion of nefopam. Indeed this analgesic is commonly used by continuous infusion by many anaesthetists to reduce its adverse effects. However whether the analgesic effect of an intermittent administration of nefopam has been proven, the efficacy of continuous infusion has not been established.

STUDY DESIGN

Double-blind placebo controlled prospective randomised study.

PATIENTS AND METHODS

Sixty patients ASA 1 to 3 undergoing planned urological surgery with laparotomy were included. At the end of surgery, bolus doses of placebo (Group 3) or nefopam 20 mg (Group 1 and 2) were administered to all the patients. Placebo (Group 3), nefopam 80 mg (Group 1) or 120 mg (Group 2) was thereafter continuously infused over 24 hours. All patients received additional analgesia with PCA morphine. We measured pain at rest and on cough with VAS. Adverse side effects such as nausea and vomiting, sedation and respiratory depression were evaluated. Mental performance was measured with mini mental status tests.

RESULTS

Patients were older in the placebo group by approximately six years but anesthetic and surgical variables were not different between groups. Pain at rest and on cough was not statistically different between groups. In the placebo group, the median (interquartile range) morphine consumption reached 29 mg (13-53) whereas in patients receiving 80 and 120 mg nefopam, it levelled to 44 mg (11-54) and 35 mg (9-82) respectively (p > 0.05). Patients needed morphine during the same time period whether they received nefopam or not. Patients suffering from adverse effects were similar between groups.

CONCLUSION

In this study, continuous administration of nefopam did not reduce morphine consumption nor ameliorate analgesia and thus may not be recommended in urological surgery. Nefopam pharmacokinetics when used with continuous infusion as well as surgery types and differences in age between groups may explain these results.

Single-Dose Parenteral Pharmacological Interventions for the Prevention of Postoperative Shivering: A Quantitative Systematic Review of Randomized Controlled Trials

Shivering is a frequent complication in the postoperative period. The relative efficacy of pharmacological interventions to prevent this phenomenon is not well understood. We performed a systematic search for full reports of randomized comparisons of prophylactic, parenteral, single-dose antishivering interventions with inactive control (placebo or no treatment). Variable doses were converted to fixed doses. Dichotomous data on the absence of shivering were analyzed by using relative benefit (RB) and number needed to treat (NNT) with 95% confidence intervals (CI). Data from 27 trials (1348 adults received an antishivering intervention; 931 were controls) were analyzed. The average incidence of shivering in controls was extremely frequent (52%). Clonidine 65-300 microg (1078 patients), meperidine 12.5-35 mg (250 patients), tramadol 35-220 mg (250 patients), and nefopam 6.5-11 mg (204 patients) were tested in at least 3 trials each. All were more effective than control. For clonidine, meperidine, and nefopam, there was some weak evidence of dose responsiveness. For small-dose clonidine (65-110 microg), the RB compared with control was 1.32 (95% CI, 1.16-1.51); for medium-dose clonidine (140-150 microg), the RB was 1.83 (95% CI, 1.47-2.27); and for large-dose clonidine (220-300 microg), the RB was 1.52 (95% CI, 1.30-1.78). For all clonidine regimens combined, the RB was 1.58 (95% CI, 1.43-1.74), with an NNT of 3.7. For all meperidine regimens combined, the RB was 1.67 (95% CI, 1.37-2.03), with an NNT of 3. For all tramadol regimens combined, the RB was 1.93 (95% CI, 1.56-2.39), with an NNT of 2.2. For all nefopam regimens combined, the RB was 2.62 (95% CI, 2.02-3.40), with an NNT of 1.7. Methylphenidate, midazolam, dolasetron, ondansetron, physostigmine, urapidil, and flumazenil were tested in no more than 3 trials each, with a limited number of patients.

Nefopam potentiates morphine antinociception in allodynia and hyperalgesia in the rat

The objective of this study was to resolve discrepancies regarding the possible antinociceptive synergy between morphine and nefopam in animal models of pain. Firstly, we have examined the antinociceptive activity of nefopam, a nonopioid antinociceptive compound that inhibits monoamine reuptake, in pain models of allodynia and hyperalgesia induced by carrageenan injection, or skin and muscle incision of the rat hind paw. Single subcutaneous administration of nefopam at 30 mg/kg blocked carrageenan- and incision-induced thermal hyperalgesia, and weakly but significantly diminished carrageenan-induced tactile allodynia. A weaker dose of nefopam (10 mg/kg) only reduced carrageenan-induced tactile allodynia and incision-induced thermal hyperalgesia. Secondly, we assessed the usefulness of the coadministration of nefopam with morphine. Combination of a nonanalgesic dose of nefopam (10 mg/kg) with a nonanalgesic dose of morphine (0.3 or 1.0 mg/kg) completely inhibited carrageenan- or incision-induced thermal hyperalgesia, respectively. In carrageenan-induced tactile allodynia, coadministration of weak analgesic doses of nefopam (10 and 30 mg/kg) with a nonanalgesic dose (1 mg/kg) or moderately analgesic dose (3 mg/kg) of morphine significantly reduced or reversed allodynia, respectively. In conclusion, coadministration of nefopam with morphine enhances the analgesic potency of morphine, indicating a morphine sparing effect of nefopam.

Prise en charge des douleurs aiguës en médecine ambulatoire

An emergency. When treating a patient, relief of any acute pain is a priority. Such pain should be treated as an emergency, rapidly and effectively. Assessment is the first step Pain is a subjective phenomenon. Assessment of its intensity is the first step to its management. Regarding treatment The molecules that can be used for the treatment of acute pain in ambulatory patients can be classified into two categories, co-analgesics (antispasmodics and non-steroidal antiinflammatories) and pure analgesics classified by the WHO into three grades, although this classification presents certain limits. Nefopam is a central analgesic, with non-opiate action and, because of this inscribed by the WHO in the first grade, but with an analgesic capacity that corresponds to the substances of grade II analgesics. Its efficacy relies on medullar and/or supramedullar mechanisms. Via intramuscular injection The delay before action is of around 10 to 20 minutes and lasts for around 6 hours. The advantages of intramuscular nefopam are its analgesic capacity, its simplicity of use and its tolerance. The indications In ambulatory patients, Acupan is administered during acute arthritic pain, post-trauma and dental pain, renal colic, extremely severe migraine and headaches, dysmenorrhoea, and intense spasmodic colic.

The Median Effective Dose of Nefopam and Morphine Administered Intravenously for Postoperative Pain After Minor Surgery: A Prospective Randomized Double-Blinded Isobolographic Study of Their Analgesic Action

The aim of this study was to characterize the nature of analgesic interaction between nefopam and morphine administered i.v. for postoperative pain after minor surgery. To do so, we defined the median effective analgesic dose (ED(50)) for each drug and also the median ED(50) of their combination and compared them using the isobolographic method. Determination of median effective doses was performed by the up-and-down sequential drug administration in a two-stage study. First, in a prospective, randomized, double-blinded study, we enrolled 60 patients with mild to moderate pain after minor surgery; this was followed by an open study enrolling 30 patients. The end-point was a pain score less than 3 on a Numerical Pain Scale (0-10). Initial doses were 16 mg in group N, 5 mg in group M, and 7.5 mg of N combined with 2.5 mg of M in group N+M. The testing interval was 2 mg in group N, 1 mg in group M, and 1.5 mg of N combined with 0.5 mg of M in group N+M. ED(50) (95% confidence interval) was 5 mg (4-6 mg) for morphine, 18 mg (16-18 mg) for nefopam, and 4 mg (3.5-4.5 mg) with 12 mg (10.5-13.5 mg) for the combination of morphine and nefopam administered at a 3:1 dose ratio. Isobolographic analysis demonstrated a significant infra-additive interaction. The incidence of side effects did not differ significantly among morphine, nefopam, and their combination. These findings suggest that the combination of nefopam and morphine does not offer any advantage compared to each drug administered i.v. or alone after minor surgery. This study is the first to define the ED(50) of nefopam and morphine in postoperative patients. In conclusion, the addition of nefopam has a morphine-sparing effect, but the combination is infra-additive.

IMPLICATIONS

Pharmacologic interaction between nefopam and morphine shows infra-additivity but their combination may be clinically useful as morphine consumption is decreased in postoperative patients.

Randomized prospective study of the analgesic effect of nefopam after orthopaedic surgery † †Declaration of interest. This work has been sponsored by Biocodex Laboratories, in charge of nefopam (Acupan injectable™) commercialization

BACKGROUND

Balanced postoperative analgesia combines non-narcotic drugs and opioids. We organized a large study to evaluate nefopam analgesia and tolerance in combination with morphine for patient-controlled analgesia (PCA) after orthopaedic surgery.

METHODS

Two hundred and one patients scheduled to undergo hip arthroplasty were included in this multicentre (n=24), double-blind, randomized study comparing nefopam (20 mg every 4 h for 24 h) with placebo, the first dose being infused peroperatively. The primary outcome measure was the cumulative morphine dose received postoperatively by PCA over 24 h. Secondary outcome measures were the amount of morphine received as a loading dose in the postanaesthesia care unit (PACU) and during the 24-h observation period, and pain assessments using a visual analogue scale (VAS) and a verbal pain scale (VPS), patient's satisfaction with analgesia and treatment tolerance.

RESULTS

The two groups were comparable with respect to their characteristics and preoperative pain assessment. PCA-administered morphine over 24 h was significantly less for the nefopam group than the control group (21.2 (15.3) and 27.3 (19.2) mg respectively; P=0.02). This morphine-sparing effect was greater (35.1%) for patients with severe preoperative pain (VAS>30/100). For the entire study period (loading dose and PCA), morphine use was less for the nefopam group (34.5 (19.6) vs 42.7 (23.6) mg; P=0.01). Pain VAS at PACU arrival and during the whole PACU period was significantly lower for the nefopam than for the placebo group (P=0.002 and 0.04 respectively). Patient satisfaction was similar for the nefopam and placebo groups.

CONCLUSION

In combination with PCA morphine, nefopam gives significant morphine-sparing with lower immediate postoperative pain scores without major side-effects. This analgesic effect seems to be particularly notable for patients with intense preoperative pain.

Nefopam and tramadol for the prevention of shivering during neuraxial anesthesia

BACKGROUND AND OBJECTIVES

In patients undergoing neuraxial anesthesia, heat loss and core-to-peripheral redistribution of body heat causes the core temperature to decrease. The shivering threshold is therefore reached soon, and more shivering is required to prevent further hypothermia. Because shivering has deleterious metabolic and cardiovascular effects, it should ideally be prevented by pharmacologic or other means. We evaluated the usefulness of intravenous (IV) nefopam and tramadol in preventing and reducing the severity of shivering in patients undergoing neuraxial anesthesia for orthopedic surgery.

METHODS

Ninety patients, scheduled for neuraxial anesthesia (epidural or subarachnoid) for lower limb orthopedic surgery, were prospectively enrolled. Patients were randomly assigned to 1 of 3 groups. Immediately before neuraxial anesthesia, 30 patients received 0.15 mg/kg(-1) IV nefopam in 10 mL saline, 30 patients received 0.5 mg/kg(-1) IV tramadol in 10 mL saline, and a control group of 30 patients received 10 mL IV saline. Neuraxial anesthesia was induced at the L3-L4 or L4-L5 interspaces with 1 mg/kg(-1) mepivacaine for epidural anesthesia and 0.2 mg/kg(-1) for subarachnoid anesthesia. An investigator blinded to the antishivering drug injected recorded the frequency and degree of shivering.

RESULTS

The overall frequency and the intensity of shivering was significantly lower in patients treated with nefopam than in those treated with tramadol or placebo (P <.05 and P <.01) and in patients treated with tramadol than in those treated with placebo (P <.05).

CONCLUSIONS

As a pharmacologic means of preventing shivering in patients undergoing neuraxial anesthesia, nefopam may hold the greatest promise.

Postanaesthetic shivering: epidemiology, pathophysiology, and approaches to prevention and management

Along with nausea and vomiting, postanaesthetic shivering is one of the leading causes of discomfort for patients recovering from general anaesthesia. The distinguishing factor during electromyogram recordings between patients with postanaesthetic shivering and shivering in fully awake patients is the existence of clonus similar to that recorded in patients with spinal cord transection. Clonus coexists with the classic waxing and waning signals associated with cutaneous vasoconstriction (thermoregulatory shivering). The primary cause of postanaesthetic shivering is peroperative hypothermia, which sets in because of anaesthetic-induced inhibition of thermoregulation. However, shivering associated with cutaneous vasodilatation (non-thermoregulatory shivering) also occurs, one of the origins of which is postoperative pain. Apart from causing discomfort and aggravation of pain, postanaesthetic shivering increases metabolic demand proportionally to the solicited muscle mass and the cardiac capacity of the patient. No link has been demonstrated between the occurrence of shivering and an increase in cardiac morbidity, but it is preferable to avoid postanaesthetic shivering because it is oxygen draining. Prevention mainly entails preventing peroperative hypothermia by actively rewarming the patient. Postoperative skin surface rewarming is a rapid way of obtaining the threshold shivering temperature while raising the skin temperature and improving the comfort of the patient. However, it is less efficient than certain drugs such as meperidine, clonidine or tramadol, which act by reducing the shivering threshold temperature.

Analgesic efficacy and safety of nefopam vs. propacetamol following hepatic resection

In order to compare the morphine-sparing effect, analgesic efficacy and tolerance of nefopam and propacetamol given at their highest recommended doses, 120 patients undergoing elective hepatic resection were randomly assigned to receive postoperative intravenous patient-controlled analgesia with morphine alone, or in combination with nefopam (20 mg.4 h-1) or propacetamol (2 g.6 h-1). Compared with the control group (43 [7-92] mg), median [range] cumulative morphine consumption for 24 h after the study started was halved in the nefopam group (21 [3-78] mg, p <0.001) and 20% lower in the propacetamol group (35 [6-84] mg, p = 0.15). Analgesia was superior in the nefopam group despite the lower morphine consumption. Adverse effects were comparable in the three groups, except for significantly more nausea in the control group (39% vs. 17 and 26% in the nefopam and propacetamol groups, respectively) and more sweating in the nefopam group (17% vs. 0 and 3% in the control and propacetamol groups, respectively). Overall patient satisfaction was better (p < 0.001) in patients given nefopam (97%) than those receiving morphine alone (82%) or propacetamol (74%).

[The use of Oxadol in tablet form for the treatment of chronic pain syndrome in late-stage cancer patients]

Chronic pain management with tablets of oxadol, a non-narcotic central-action analgetic, was studied in 30 patients, focusing on combinations with "basic" drugs of the opiate and opioid group. Combined administration of tramal and oxadol for moderate pain relief raised the analgesic effect and improved certain parameters of quality of life. Possible side-effects and indications in cases of well-advanced tumor were established.

Nefopam and clonidine in the prevention of postanaesthetic shivering

Postanaesthetic shivering affects up to 70% of patients after general anaesthesia, and may be very distressing. Various drugs have been used to treat or prevent postanaesthetic shivering, but the ideal one has not yet been found. Sixty patients undergoing elective abdominal or orthopaedic surgery under general anaesthesia were included in a randomised, double-blind study. Patients received clonidine (3 microgram.kg-1), nefopam (0.15 mg.kg-1) or saline 0.9% as a placebo at the end of surgery, prior to extubation. Nefopam and clonidine significantly reduced the incidence and severity of shivering in comparison with the placebo. The recovery time, between the end of anaesthesia and extubation, was significantly longer in the clonidine-treated patients [13.6 (5.2) min] than in either the nefopam [9.6 (2.8) min] or the placebo [10.0 (5.4) min] groups. Mean arterial blood pressure and heart rate were significantly lower in the clonidine group compared with both other groups. Our results suggest that nefopam and clonidine are effective in the prevention of postanaesthetic shivering. However, following clonidine administration the recovery time was prolonged and hypotension was significantly greater than after nefopam.

[Postoperative oxadol analgesia in oncologic patients]

Oxadol (nefopam hydrochloride), a central analgesic, was used for postoperative pain relief in patients operated on the abdominal and pelvic organs for cancer. The analgesic effect of oxadol was sufficient for arresting moderate postoperative pain. Although the drug exerts rather many side effects, none of them notably deteriorated the clinical status of patients.

[Prophylactic nefopam administration for post-anesthetic shivering]

PURPOSE

Shivering is a frequent postanaesthetic complication. Its definite reason is unknown. Patients with cardiovascular or pulmonary diseases are endangered by postanaesthetic shivering. The aim of this study was to assess the efficacy of nefopam in prophylaxis of shivering. Additionally we investigated the influence of nefopam on haemodynamic parameters and on the time until extubation.

METHODS

30 patients (ASA I-II) were randomly allocated in a double-blind fashion to one of two groups to receive directly after the end of isoflurane application either nefopam (0.15 mg/kg) or placebo (0.9% saline). The period of anaesthesia had to be longer than 60 minutes. All patients received a premedication with lorazepam (0.02 mg/kg) 30-45 minutes prior to surgery. Induction of anaesthesia was standardised: fentanyl (3 micrograms/kg), thiopentone (5 mg/kg), atracurium (0.4 mg/kg). Intraoperatively a mixture of isoflurane, nitrous oxide (60%) and oxygen was used to maintain anaesthesia. The following parameters were evaluated: Age, sex, duration of operation and anaesthesia and the time between the end of application of volatiles and extubation. Heart rate (HR), mean arterial blood pressure (MAP), rectal temperature and O2-saturation were measured at predefined data points. Postoperatively the consumption of analgesic was documented. The severity of shivering was classified in five grades.

RESULTS

In the control-group nine patients shivered (60%), whereas in the nefopam group only one patient (6.6%) shivered (p < 0.05). In comparison to the placebo group we observed in the nefopam group a significantly decreased HR 30 and 60 minutes postoperatively (p < or = 0.007 and p < or = 0.002). We did not observe prolonged awakening in the nefopam-treated patients. MAP and O2-saturation showed similar reactions in both groups.

CONCLUSION

The data indicate that prophylactic administration of nefopam can suppress postanaesthetic shivering. Prolonged awakening was not observed.

Efficacy of nefopam for the prevention and treatment of amphotericin B-induced shivering

BACKGROUND

Shivering is experienced by up to 70% of patients undergoing amphotericin B therapy. Treatment with meperidine hydrochloride, currently the most widely used medication for controlling amphotericin B-induced shivering, was compared with nefopam hydrochloride, which has been successfully used to treat post-operative shivering.

METHODS

Forty-five patients with cancer and systemic fungal infections randomly received nefopam hydrochloride, 0.3 mg/kg, meperidine hydrochloride, 0.7 mg/kg, or saline solution intravenously 15 minutes before the cessation of amphotericin B infusion (1 mg/kg for 45 minutes). If shivering persisted, patients in the control (saline solution) group received either nefopam hydrochloride, 0.3 mg/kg, or meperidine hydrochloride, 0.7 mg/kg.

RESULTS

Occurrence of shivering 15 minutes after the cessation of amphotericin B infusion was significantly less frequent in the nefopam (6.6%) and meperidine (40%) groups compared with the control group (66.6%). The incidence of shivering in the nefopam group with respect to the meperidine group was also significantly reduced. Moreover, nefopam administration to 5 persistently shivering patients in the control group definitively stopped the shivering in all of them (100%) in a mean (+/- SD) time of 29.1 +/- 4.8 seconds, while meperidine terminated shivering in 4 (80%) of 5 patients in a mean (+/- SD) time of 200.0 +/- 30.2 seconds. The adverse reactions that can be ascribed to nefopam or meperidine use were nausea and sedation, respectively, and may be considered negligible.

CONCLUSION

Nefopam seems to be more effective than meperidine in preventing and quickly suppressing amphotericin B-induced shivering.

Control of post anaesthetic shivering with nefopam hydrochloride in mildly hypothermic patients after neurosurgery

Postoperative shivering may be prevented by maintaining normothermia intraoperatively or it may be treated using specific drugs. The aim of this study was to compare the efficacy of nefopam hydrochloride (nefopam) to that of clonidine and meperidine in patients undergoing elective neurosurgical procedures. Three groups of patients were included in the study. Patients in group A (60) received i.v., at random, 20 mg of nefopam, 50 mg of meperidine or 150 micrograms of clonidine in the immediate postoperative period. The incidence of shivering and the time at which shivering ceased were noted, along with central temperature and main haemodynamic changes. Group B (20) received i.v., at random, either 10 mg of nefopam or saline before awakening from anaesthesia. The effects of nefopam on central temperature, oxygen consumption (Vo2), carbon dioxide production (VcO2), basal metabolic rate (BMR) and energy expenditure (EE) were investigated. Group C (10) received i.v. 20 mg of nefopam during surgery: cerebrospinal fluid pressure (CSFP), cerebral perfusion pressure (CPP) and electroencephalogram (EEG) were monitored. In group A nefopam stopped shivering in 95% of patients when compared to meperidine and clonidine, which were effective in 32% and 40% of patients respectively. In group B, only 10% of patients receiving nefopam had postoperative shivering, Vo2, VcO2 and EE were significantly lower in patients treated with nefopam than those in the control group. No changes in CSFP, CPP or EEG were observed in group C. In conclusion, nefopam seems to be more effective than clonidine or meperidine in quickly suppressing shivering, without producing significant adverse reactions.

Comparative evaluation of intramuscular buprenorphine, pentazocine and nefopam in post-operative pain relief

In immediate postoperative period, many injectable analgesics are being used with diverse side effects. The present study was conducted on 75 patients of both sexes, who underwent various types of surgery, to evaluate pain relief in immediate postoperative period. The drugs used for producing postoperative analgesia are buprenorphine, pentazocine and nefopam, all by intramuscular route.

[The use of nefopam in the prophylaxis and treatment of postoperative shivering]

Chlorhydrate nefopam was used in the prophylaxis and treatment of postoperative shivering in 54 patients undergoing general anesthesia for radical cystectomy with trans-intestinal anastomosis. Postoperative shivering was not observed in any of the patients treated with nefopam before coming round, whereas it occurred in 55% of patients treated with placebo. Chlorhydrate nefopam subsequently stopped shivering in all these patients. The main side effects observed took the form of delayed awakening in 11% of patients receiving prophylactic treatment and somnolence lasting 5-10 minutes in all other patients.

The effect of diclofenac and nefopam on postoperative dental pain

Eighty-two outpatients who received general anaesthesia for surgical removal of maxillary or mandibular third molars were given either diclofenac 75 mg or nefopam 20 mg intramuscularly for postoperative pain control. They and the control group were also allowed oral paracetamol as required. The results showed that there was no significant pain relief from these single intramuscular injections.

Postoperative nefopam and diclofenac. Evaluation of their morphine-sparing effect after upper abdominal surgery

The aim of the study was to assess the relative morphine-sparing effects of nefopam and diclofenac when used singly or in combination after upper abdominal surgery. Eighty-four patients of ASA grade 1 or 2 were allocated randomly to one of three groups. Group A received nefopam 20 mg by intramuscular injection 6 hourly after surgery for the 24-hour study period. Group B received diclofenac 75 mg 12-hourly and placebo injections at 6 and 18 hours after surgery. Group C received both 6-hourly nefopam and 12-hourly diclofenac. Supplemental analgesia was given on demand via a patient-controlled analgesia system which delivered intravenous morphine. Morphine requirements in the diclofenac group were significantly lower than in either of the other groups (p less than 0.01). Patients who received the combination of nefopam and diclofenac required significantly less morphine than those who received nefopam alone (p less than 0.01). Pain scores assessed 6 hours after surgery were significantly lower in the diclofenac and combination groups compared with the nefopam group (p less than 0.01).

Double-blind clinical trial of nefopam in comparison with pentazocine in surgical patients

A double-blind clinical study comparing a new non-narcotic analgesic, nefopam, with pentazocine was carried out on 50 Indian patients. Forty patients had undergone surgical procedures, and the remaining 10 had musculoskeletal or traumatic disorders. There were 25 patients in each group. It was observed that both drugs were capable of relieving post-surgical pain which was either very severe (score 4) or severe (score 3). Their efficacy was comparable. In patients who had an initial pain score of 4, a significant (p less than 0.05) fall in the sum of pain intensity scores (SPIS) occurred in two days. For an initial pain score of 3, a correspondingly significant fall in SPIS took three days. These results were statistically significant (p less than 0.01). Nefopam had a significantly better side effect profile than pentazocine. In the nefopam group, 4/25 patients had side effects, as opposed to 10/25 in the pentazocine group (p less than 0.05, Fisher's exact probability test). It was also noted that the incidence of side effects was greater in the pentazocine group (61) than the nefopam group (22), the difference being statistically highly significant (p less than 0.001, chi 2-test). A few patients (score 4) in both groups required additional morphine as relief analgesic on the first day of therapy. Thus the non-narcotic nefopam is equally effective as the narcotic pentazocine and has less side effects.

Double-blind evaluation of analgesic efficacy of orally administered diclofenac, nefopam, and acetylsalicylic acid (ASA) plus codeine in chronic cancer pain

The analgesic efficacy and toxicity of oral diclofenac sodium 50 mg (q.i.d.) vs. nefopam 60 mg (q.i.d.) and a combination of 640 mg ASA and 40 mg codeine (q.i.d.) in cancer patients with moderate to severe chronic pain has been evaluated in a randomized double-blind study. Planned duration of treatment was 10 days. Pain intensity was evaluated by a visual analog scale. The length of patient participation in the trial, the patient's final global evaluation and the incidence of side effects were also evaluated. Ninety-nine patients were enrolled in the study. All treatments produced a statistically significant pain relief (P less than 0.01) without differences among groups but only 26 of 99 patients (26.3%) completed the planned treatment period. Mean time in the study was 4.65 days. Inefficacy and side effects were the main reasons for premature treatment interruption. Patients treated with nefopam had a significantly shorter period in the study than patients treated with the other 2 treatments. Adverse effects were slightly more frequent with the nefopam and ASA + codeine regimens. The 3 therapeutic regimens appear to be similar as to analgesic efficacy, but diclofenac presents the advantage of a slightly better safety profile than nefopam and the ASA + codeine combination.

A comparison of nefopam and flurbiprofen in the treatment of osteoarthrosis

A double-blind cross-over study was undertaken comparing the analgesic nefopam with the NSAID flurbiprofen in the treatment of osteoarthritis of the knees. Thirty patients entered the study and 18 completed the full trial protocol of one month on each drug. There was no significant difference in efficacy between the two treatments, although there were more side effects during the nefopam period. These must be balanced against the known gastrotoxicity of NSAIDs when choosing symptomatic treatment for osteoarthrosis.