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

Abstract

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.

Efficacy of dexmedetomidine on postoperative shivering: a meta-analysis of clinical trials

“…1 Despite the benefits from reducing heat loss, shivering increases the patients' oxygen consumption, carbon dioxide production, and energy expenditure, 2 and it may cause severe adverse effects during the recovery from general anesthesia, especially in patients with impaired cardiac and pulmonary reserves. Moreover, for awake patients, shivering is an uncomfortable experience, sometimes even worse than surgical pain.…”

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

“…Although the mechanisms underlying the analgesic action of nefopam are unclear, the drug does not bind to opiate receptors, but inhibits synaptic uptake of several neurotransmitters, including dopamine, norepinephrine and serotonin [19,20]. Ample evidence confirms the efficacy of nefopam for the treatment [2] and prevention [4][5][6] of postanaesthetic shivering. Our findings now confirm its efficacy for preventing peri-operative shivering in patients undergoing conscious sedation.…”

“…Although numerous papers have addressed the problem of postoperative shivering after general anaesthesia and during neuraxial anaesthesia [1][2][3][4][5][6], none have investigated the troublesome problem of shivering during and after conscious sedation. For interventional neuroradiology, the preferred anaesthetic technique is conscious sedation.…”

“…Pharmacological prevention minimises the increase in metabolic activity and cardiac work [5]. Nefopam (3,4,5,6-tetrahydro-5-methyl-l-phenyl-1H-2.5-benoxazocine hydrochloride) is a non-opioid analgesic drug that is safe and effective in preventing shivering after general and neuraxial anaesthesia with little effect on the sweating and vasoconstriction thresholds [2,[4][5][6]13]. Unlike clonidine, nefopam has no sedative or hypotensive effects.…”

“…Shivering can be prevented by maintaining normothermia [11,12] or pharmacologically [1][2][3][4][5][6]. Pharmacological prevention minimises the increase in metabolic activity and cardiac work [5].…”