Clonidine at induction reduces shivering after general anaesthesia

Abstract

Purpose: Postanaesthetic shivering occurs in 5-65% of patients. In addition to causing discomfort, it is associated with deleterious consequences. Our objective was to investigate the effect of 150/ag clonidine, at induction of anaesthesia, on perioperative core and peripheral temperature, incidence of postanaesthetic shivering and patients' perception of cold. Methods: Sixty ASA I or 2 patients scheduled for elective orthopaedic limb surgery were randomly allocated to group I, who received 150/Jg clonidine iv, or group 2, who received a saline bolus iv, before induction. In alI patients, anaesthesia was induced with fentanyl and propofol and maintained by spontaneous respiration (via a laryngeal mask airway) of oxygen, nitrous oxide and enflurane. Core (nasopharyngeal) and peripheral (dorsal hand) temperatures were recorded at induction and 15-rain intervals. Nurses, unaware of the treatment groups, recorded visible shivering in the recovery room, When cognitive function returned, patients were asked to grade their perception of cold on a I 0 cm linear analogue scale, higher scores indicating heat discomfort.Results: While core temperature decreased and peripheral temperature increased in both groups, there was no difference between the groups at any time. However, there was a lower incidence of shivering in the clonidine group (20% vs 66.7% P <0.00l ). Patients receiving clonidine felt warmer; thermal comfort score (median interquartile range) 5.9 (5.0-7.2) vs 5.0 (4.5-6.0), P <0.05).Conclusion: Clonidine 150 g iv at induction of anaesthesia reduces the incidence of shivering and patients' subjective perception of cold on emergence from general anaesthesia. R~sultats : Alors que la temp&ature centrale diminuait et la temp&ature pEriphErique augmentait dans les deux groupes, aucune difference if&at notEe entre les groupes. Cependant, I'incidence du flisson Etalt plus basse dans le groupe clonidine (20% vs 66,7%, P <0,00 I). La perception de chaleur Etait plus ElevEe chez les patients sous clonidine avec un score de comfort (mEdiane &art interquartile de) 5,9 (5,0-7,2) vs 5,0 (4,5-6,0), P <0,05). Conclusion : AdministrEe ~. (induction, la donidine iv r~duit rincidence du fdsson et [a sensation subjective de froid per~ue au r~veil apr~s une anesth&ie gEn&ale.

THIS ARTICLE HAS BEEN RETRACTED Nefopam and clonidine in the prevention of postanaesthetic shivering

“…The major finding was that there was no statistically significant difference between the efficacy of nefopam and clonidine in the prevention of postanaesthetic shivering, whereas both substances were beneficial when compared with the placebo. Postanaesthetic shivering is a common phenomenon and in our placebo group the incidence was 60%, a figure that is in accord with other studies [1,10,13]. Several drugs have been recommended [14][15][16][17][18][19][20], but the ideal drug for prevention and therapy has still not been found [9].…”

“…Furthermore, nefopam did not influence the recovery time, which is not surprising because nefopam has no sedative effects [22]. Several studies have shown a similar beneficial effect of clonidine for the treatment and prevention of shivering [1,5,10,17]. However, clonidine has well-known sedative properties and may reduce postanaesthetic shivering secondary to sedation of the patients [27].…”

“…Postanaesthetic shivering is a rhythmic oscillating movement, predominantly involving the upper limbs, neck and jaw, that occurs in 5-70% of patients recovering from general anaesthesia [1][2][3] and Ϸ 30% of volunteers during epidural anaesthesia [4]. Postanaesthetic shivering may produce complications, especially in patients with coronary artery disease, secondary to increased oxygen consumption, cardiac output, carbon dioxide production, and circulating catecholamines and decreased mixed venous saturation [1,5,6].…”

“…Postanaesthetic shivering may produce complications, especially in patients with coronary artery disease, secondary to increased oxygen consumption, cardiac output, carbon dioxide production, and circulating catecholamines and decreased mixed venous saturation [1,5,6]. Moreover, in shivering patients an increase in intracerebral and intraocular pressure, interference with monitoring of ECG and blood pressure, and lactic acidosis have been described [3,[7][8][9].…”

“…Various drugs have been suggested for postanaesthetic shivering, including metamizol, pethidine, ketanserin, sufentanil, alfentanil, tramadol, physostigmine, urapidil, doxapram and nalbuphine [3,5,[14][15][16][17][18][19][20]. Several studies have also described the efficacy of clonidine for prophylaxis and treatment of postanaesthetic shivering [1,5,10]. The action of clonidine appears to be related to central thermoregulatory inhibition because it comparably reduces the vasoconstriction and shivering thresholds [17].…”