Nefopam and tramadol for the prevention of shivering during neuraxial anesthesia

Nefopam for the prevention of perioperative shivering: a meta-analysis of randomized controlled trials

BACKGROUND

Shivering is a frequent complication following surgery and anaesthesia. A large variety of studies have been reported that nefopam may be efficacious for the prevention and treatment of perioperative shivering. Regrettably, there is still no conclusion of the efficacy and safety of nefopam for the prevention of perioperative shivering. The aim of this analysis is to evaluate the efficacy of nefopam for the prevention of perioperative shivering in patients undergoing different types of anaesthesia compared with placebo group and other active interventions.

METHODS

PubMed, EMBASE, Cochrane Central Register of Control Trials were systematically searched for potentially relevant trials. Trial quality and extracted data were evaluated by two authors independently. Dichotomous data on the absence of shivering was extracted and analysed by using relative risk (RR) with 95% confidence interval (CI). Continuous outcome was abstracted and analysed by using weighted mean difference (WMD) with 95% confidence interval (CI). Outcome data was analysed by using random effect model or fixed effect model in accordance with heterogeneity.

RESULTS

Compared with placebo, prophylactic administration of nefopam significantly reduced the risk of perioperative shivering not only in the patients under general anaesthesia but also neuraxial anaesthesia (RR 0.08; 95% CI 0.05-0.13). As compared with clonidine, nefopam was more efficacious in the prevention of perioperative shivering (RR 0.34; 95% CI 0.17-0.70). Nefopam has no influence on the extubation time (WMD 0.92; 95% CI -0.15-1.99).

CONCLUSION

Our analysis has demonstrated that nefopam is associated with the decrease of risk of perioperative shivering following anaesthesia without influencing the extubation time.

A randomised trial comparing efficacy, onset and duration of action of pethidine and tramadol in abolition of shivering in the intra operative period

INTRODUCTION

Regional anaesthesia (spinal anaesthesia) is widely used as a safe anaesthetic technique for both elective and emergency operations. Shivering is known to be a frequent complication, reported in 40 to 70% of patients undergoing surgery under regional anaesthesia. Various methods are available for the control of shivering during anaesthesia. Here we have compared Tramadol, a synthetic opioid with Pethidine, the gold standard drug for the treatment of shivering, in the quest for more safe and efficacious drug.

MATERIALS AND METHODS

Forty patients of ASA 1 and 2 status posted for elective surgical procedures under neuraxial block were selected. Group P (n=20) received Pethidine 0.5mg/kg IV and group T (n=20) received tramadol 1.0 mg/kg IV.

RESULTS

Both the drugs were found to be effective in reducing shivering. Nineteen patients in the Group T had control of shivering at end of 5 minutes but there were no patients who had control of shivering Group P (p < 0.0001) which is statistically significant.

CONCLUSION

Tramadol reduced the occurrence of postanesthetic shivering more significantly than pethidine.

Use of oral tramadol to prevent perianesthetic shivering in patients undergoing transurethral resection of prostate under subarachnoid blockade

Context:

Under regional anesthesia, geriatric patients are prone to shivering induced perioperative complications that Anesthesiologists should prevent rather than treat.

Aim:

We investigated the prophylactic efficacy of oral tramadol 50 mg to prevent the perioperative shivering after transurethral resection of prostate (TURP) surgery under subarachnoid blockade (SAB). Shivering is usually overlooked in patients undergoing urological surgery under spinal anesthesia and may result in morbidity, prolonged hospital stay and increased financial burden. Use of prophylactic measures to reduce shivering in geriatric patients who undergo urological procedures could circumvent this. Oral formulation of tramadol is a universally available cost-effective drug with the minimal side-effects.

Settings and Design:

Prospective, randomized, double-blinded, placebo-controlled study.

Patients and Methods:

A total of 80 patients who were scheduled for TURP surgery under subarachnoid block were randomly selected. Group I and II (n = 40 each) received oral tramadol 50 mg and placebo tablet respectively. After achieving subarachnoid block, the shivering, body temperature (tympanic membrane, axillary and forehead), hemodynamic parameters and arterial saturation were recorded at regular intervals.

Statistical Analysis Used:

T-test, analysis of variance test, Z-test and Fisher exact test were utilized while Statistical Product and Service Solutions, IBM, Chicago (SPSS statistics (version 16.0)), software was used for analysis.

Results:

Incidence of shivering was significantly less in patients who received tramadol (7.5% vs. 40%; P < 0.01). The use of tramadol was associated with clinically inconsequential side-effects.

Conclusion:

We conclude that the use of oral tramadol 50 mg is effective as a prophylactic agent to reduce the incidence, severity and duration of perioperative shivering in patients undergoing TURP surgery under SAB.

Comparison of meperidine and nefopam for prevention of shivering during spinal anesthesia

BACKGROUND

Shivering is a frequent event during spinal anesthesia and meperidine is a well-known effective drug for prevention and treatment of shivering. Nefopam is a non-opiate analgesic and also known to have an anti-shivering effect. We compared nefopam with meperidine for efficacy of prevention of shivering during spinal anesthesia.

METHODS

Sixty five patients, American Society of Anesthesiologists physical status I or II, aged 20-65 years, scheduled for elective orthopedic surgery under spinal anesthesia were investigated. Patients were randomly divided into two groups, meperidine (Group M, n = 33) and nefopam (Group N, n = 32) groups. Group M and N received meperidine 0.4 mg/kg or nefopam 0.15 mg/kg, respectively, in 100 ml of isotonic saline intravenously. All drugs were infused for 15 minutes by a blinded investigator before spinal anesthesia. Blood pressures, heart rates, body temperatures and side effects were checked before and at 15, 30, and 60 minutes after spinal anesthesia.

RESULTS

The incidences and scores of shivering were similar between the two groups. The mean arterial pressures in Group N were maintained higher than in Group M at 15, 30, and 60 minutes after spinal anesthesia. The injection pain was checked in Group N only and its incidence was 15.6%.

CONCLUSIONS

We conclude that nefopam can be a good substitute for meperidine for prevention of shivering during spinal anesthesia with more stable hemodynamics, if injection pain is effectively controlled.

Randomized double-blind comparison of prophylactic ketamine, clonidine and tramadol for the control of shivering under neuraxial anaesthesia

Background:

Shivering is a common problem during neuraxial anaesthesia. Neuraxial anaesthesia impairs thermoregulatory control and up to a 56.7% incidence of shivering has been reported.

Aim:

To evaluate the effectiveness of prophylactic use of intravenous ketamine, clonidine and tramadol in control of shivering and to note any side-effects of the drugs used.

Setting and Design:

Randomised double-blind study.

Methods:

This study was conducted in 200 ASA grade I and II patients. Neuraxial block was performed with 2.8 mL (14 mg) of 0.5% bupivacaine heavy in all patients. The patients were randomly allocated into four groups of 50 each to receive saline as placebo (group P), ketamine 0.5 mg/kg (group K), Clonidine 75 mcg (group C) and Tramadol 0.5 mg/kg (group T). Temperature and hemodynamic parameters were recorded at every 5-min interval. Shivering was graded from 0 to 4 grades and, if grade 3 shivering occurred, the study drug was considered as ineffective and intravenous pethidine 25 mg was given as rescue drug.

Statistical Analysis:

Data among groups was compared using one-way ANOVA. The incidence of shivering and side-effects were compared using the chi-square test.

Results:

The incidence of grade 3 shivering showed a statistically significant difference (P=0.001) in group P (27/50) as compared with the other groups (group K=5/50, group C=2/50, group T=4/50). No drug showed any statistically significant advantage over the other. No major hemodynamic changes were seen with prophylactic use of test drugs; however, sedation score was significantly higher in group K (P<0.05) as compared with the other groups.

Conclusion:

The prophylactic use of ketamine, clonidine and tramadol were effective in preventing shivering during neuraxial anaesthesia without causing any major untoward side-effects.

A comparative study of the effect of clonidine and tramadol on post-spinal anaesthesia shivering

The aim of this study was to evaluate the efficacy, potency and side effects of clonidine as compared to tramadol in post–spinal anaesthesia shivering. In this prospective double-blind randomized controlled clinical trial, 80 American Society of Anaesthesiologists grade-l (ASAI) patients aged between 18 and 45 years scheduled for various surgical procedures under spinal anaesthesia, who developed shivering were selected.The patients were divided into two groups: Group C (n=40) comprised of patients who received clonidine 0.5mg/kg intravenously (IV) and group patients who received tramadol 0.5 mg/kg IV. Grade of shivering, disappearance of shivering, haemodynamics and side effects were observed at scheduled intervals. Disappearance of shivering was significantly earlier in group C (2.54±0.76) than in group T (5.01±1.02) (P=.0000001). Response rate to treatment in group C was higher (97.5%) than in group T (92.5%), but the difference was not significant. Nausea, vomiting and dizziness were found to be higher in group T (P=0.001, 0.005, 0.001, respectively), while the patients in group C were comparatively more sedated (sedation level, 2; group C, 25%). We conclude that clonidine gives better thermodynamics than tramadol, with fewer side effects.

DI. Ondansetron does not reduce the shivering threshold in healthy volunteers

BACKGROUND

Ondansetron, a serotonin-3 receptor antagonist, reduces postoperative shivering. Drugs that reduce shivering usually impair central thermoregulatory control, and may thus be useful for preventing shivering during induction of therapeutic hypothermia. We determined, therefore, whether ondansetron reduces the major autonomic thermoregulatory response thresholds (triggering core temperatures) in humans.

METHODS

Control (placebo) and ondansetron infusions at the target plasma concentration of 250 ng ml(-1) were studied in healthy volunteers on two different days. Each day, skin and core temperatures were increased to provoke sweating; then reduced to elicit peripheral vasoconstriction and shivering. We determined the core-temperature sweating, vasoconstriction and shivering thresholds after compensating for changes in mean-skin temperature. Data were analysed using t-tests and presented as means (sds); P<0.05 was taken as significant.

RESULTS

Ondensetron plasma concentrations were 278 (57), 234 (55) and 243 (58) ng ml(-1) at the sweating, vasoconstriction and shivering thresholds, respectively; these corresponded to approximately 50 mg of ondansetron which is approximately 10 times the dose used for postoperative nausea and vomiting. Ondansetron did not change the sweating (control 37.4 (0.4) degrees C, ondansetron 37.6 (0.3) degrees C, P=0.16), vasoconstriction (37.0 (0.5) degrees C vs 37.1 (0.3) degrees C; P=0.70), or shivering threshold (36.3 (0.5) degrees C vs 36.3 (0.6) degrees C; P=0.76). No sedation was observed on either study day.

CONCLUSIONS

/b>. Ondansetron appears to have little potential for facilitating induction of therapeutic hypothermia.

Nefopam or clonidine in the pharmacologic prevention of shivering in patients undergoing conscious sedation for interventional neuroradiology

The aim of this randomised, double-blind study was to investigate the usefulness of intravenous nefopam, clonidine or placebo in preventing shivering in patients undergoing conscious sedation for interventional neuroradiological procedures. A total of 101 patients were prospectively enrolled and assigned to one of three groups to receive nefopam, clonidine or placebo. The overall incidence of intra-operative shivering was significantly lower in patients treated with nefopam than in those treated with clonidine or placebo (2/32 (6%) vs. 11/38 (29%), p < 0.02; 2/32 (6%) vs. 24/31 (77%), p < 0.0001, respectively). The number of patients who required ephedrine infusions to maintain a mean arterial pressure of 100 mm Hg was higher in the clonidine group than in the nefopam and placebo groups (18/38 (47%) vs. 5/32 (17%), p < 0.05; 18/38 (47%) vs. 6/31 (19%), p < 0.05, respectively). We found that both nefopam and clonidine significantly lowered the rate and severity of shivering during interventional neuroradiological procedures. Fewer patients in the nefopam group than in the other two groups required vasoactive drugs.

Nefopam, a nonsedative benzoxazocine analgesic, selectively reduces the shivering threshold in unanesthetized subjects

BACKGROUND

The analgesic nefopam does not compromise ventilation, is minimally sedating, and is effective as a treatment for postoperative shivering. The authors evaluated the effects of nefopam on the major thermoregulatory responses in humans: sweating, vasoconstriction, and shivering.

METHODS

Nine volunteers were studied on three randomly assigned days: (1) control (saline), (2) nefopam at a target plasma concentration of 35 ng/ml (low dose), and (3) nefopam at a target concentration of 70 ng/ml (high dose, approximately 20 mg total). Each day, skin and core temperatures were increased to provoke sweating and then reduced to elicit peripheral vasoconstriction and shivering. The authors determined the thresholds (triggering core temperature at a designated skin temperature of 34 degrees C) by mathematically compensating for changes in skin temperature using the established linear cutaneous contributions to control of each response.

RESULTS

Nefopam did not significantly modify the slopes for sweating (0.0 +/- 4.9 degrees C. microg-1. ml; r2 = 0.73 +/- 0.32) or vasoconstriction (-3.6 +/- 5.0 degrees C. microg-1. ml; r2 = -0.47 +/- 0.41). In contrast, nefopam significantly reduced the slope of shivering (-16.8 +/- 9.3 degrees C. microg-1. ml; r2 = 0.92 +/- 0.06). Therefore, high-dose nefopam reduced the shivering threshold by 0.9 +/- 0.4 degrees C (P < 0.001) without any discernible effect on the sweating or vasoconstriction thresholds.

CONCLUSIONS

Most drugs with thermoregulatory actions-including anesthetics, sedatives, and opioids-synchronously reduce the vasoconstriction and shivering thresholds. However, nefopam reduced only the shivering threshold. This pattern has not previously been reported for a centrally acting drug. That pharmacologic modulations of vasoconstriction and shivering can be separated is of clinical and physiologic interest.