Shivering related to epidural blockade with bupivacaine in labour, and the influence of epidural pethidine

Abstract

A prospective survey of two hundred patients who received an epidural block in labour was performed in order to determine the incidence and severity of shivering, and the influence of likely associated factors. Twenty-two of the patients who shivered took part in a double-blind trial to see if epidural pethidine 25 mg, versus saline, had any effect upon shivering. Fifty per cent of patients shivered soon after the initial dose of bupivacaine. Shivering was more common among patients who had experienced shivering before epidural block, and in those who had received nitrous oxide (P less than 0.005). Prior intramuscular injection of pethidine did not significantly affect the incidence of shivering, and it was not influenced by the concentration of epidural bupivacaine used (0.5 or 0.25%). Shiverers were more likely to feel cold than non-shiverers (P less than 0.001) but shivering was generally regarded by patients as a trivial symptom, only 13% describing it as very irritating. Shivering was abolished or considerably diminished within ten minutes in all patients who received epidural pethidine 25 mg, whereas there was no change in eight out of eleven patients who received epidural saline. These results are significant (P less than 0.01), and demonstrate that shivering following epidural blockade can be effectively treated with small epidural doses of pethidine.