COMPARISON OF THE EFFECTS OF URAPIDIL AND SODIUM-NITROPRUSSIDE ON HEMODYNAMIC STATE, MYOCARDIAL-METABOLISM AND FUNCTION IN PATIENTS DURING CORONARY-ARTERY SURGERY

We have compared, in an open randomized study, the effects of sodium n itroprusside (SNP) and urapidil on haemodynamic state and myocardial f unction and metabolism in two groups of patients undergoing elective c oronary artery surgery. Sixty patients were allocated randomly to one of two groups: group SNP (n = 29) received SNP at an initial rate of 1 -2 mu g kg(-1) min(-1); group URA (n = 31) received one or more bolus injections of urapidil 25 mg and an i.v. infusion at an initial rate o f 11-21 mu g kg(-1) min(-1). Baseline measurements were obtained 10 mi n after introduction of an echo-transducer into the oesophagus. Subseq uently, vasodilator therapy was started in both groups. Infusion rates were adjusted to maintain systolic arterial pressure at 80-120% of ba seline values (or mean arterial pressure < 100 mm Hg). Additional meas urements were obtained 10 min after the start of vasodilator therapy a nd after sternotomy when the pericardium was opened. At each measuring time a complete haemodynamic profile, coronary sinus blood flow (CSBF ) curves, transoesophageal echocardiographic images, and arterial and coronary venous blood samples were obtained. Arterial pressure was con trolled adequately in both groups. After sternotomy, heart rate and ca rdiac index increased in both groups. At that time, there was a signif icant increase in myocardial oxygen consumption and CSBF in group URA (P < 0.05). However, the ratio between myocardial oxygen demand and ox ygen supply remained unchanged and there was no difference in the numb er of ischaemic episodes between the groups.