Stress response due to intubation. Clonidine versus Esmolol

Alpha-2-adrenoceptor-agonists as well as cardioselective beta receptor-anta gonists have been shown to blunt stress response due to tracheal intubation . The purpose of our study was to investigate, whether clonidine or esmolol is more efficient to attenuate stress response due to intubation. 44 patie nts were randomly assigned to receive either clonidine (n=22; 3 mug/kg) or esmolol (n=22; 2 mg/kg) immediately prior to a standardized induction of an aesthesia. Heart rate, arterial blood pressure, cardiac output, epinephrine and norepinephrine plasma concentrations were measured before,during and 1 0 min after intubation. Blood pressure was measured invasively and cardiac output was determined by transthoracic echocardiography. Absolute Values an d increase of mean arterial pressure and norepinephrine plasma concentratio ns were significantly less in the clonidine group (p<0,05). Clonidine (3 <m u>g/kg) is more efficient than esmolol (2 mg/kg) in blunting stress respons e due to endotracheal intubation.