Comparison between intravenous pethidine and / or clonidine in management of postextradural shivering

ABSTRACT

This study detected the efficacy of intravenous pethidine and / or clonidine to suppress post-extradural shivering in patients had lower abdominal surgery. 60 healthy patients ASA I or II who developed shivering after extradural block, were allocated randomly into 4 groups [each of 15 patients]. Group I [saline group] patients in this group received 5 ml normal saline intravenously; group II [pethidine group] patients in this group received i.v. pethidine in a dose of 0.3 mg/kg diluted with normal saline to a total volume 5 ml.; group III [clonidine group] patients in this group received clonidine 30 micro g diluted in normal saline to a total volume of 5 ml, this bolus had been repeated every 6 min. if the initial therapy produced no improvement, up to maximum dose 90 micro.g.; group IV [pethidine and clonidine group] patients in this group received i.v. pethidine and clonidine in the same previous doses and volumes. In all this patients we measured HR, mean ABP and Respiratory rate, before treatment and every 5 minutes after, up to 30 minutes. Atrial blood samples were taken before and after treatment of shivering to measure PaO[2] SaO[2],PaCO[2], HCO[3] and pH. From the present study, we found that non of the patients stopped shivering in saline group and shivering inhibited in all patients 7 min after pethidine in a dose of [0.3 mg/kg] with success rate 100%. In clonidine group, shivering was inhibited in 12 patients 6 min after treatment using [30 micro g] clonidine and the other 3 patients need the 2[nd] dose clonidine to stop shivering after 15 min., thus, the success rate was 100%. In combination group, shivering had stopped within 6 min. in 100% of the patients and they all received only one dose of clonidine [30 micro g]. There was an improvement of the respiratory rate metabolic acidosis, and no haemodynamic adverse effects of the administered doses. PaCO[2] was below normal, while PaO[2] was below normal before treatment and insignificantly improved after treatment although there was an increase in oxygen consumption during shivering and did not return to its basal line after treatment indicating that shivering patients need oxygen during and after treatment of shivering