Studies on thiopentone and midazolam hemodynamic response during induction of anesthesia in patients with coronary artery disease

Background: Induction of anesthesia in patients that undergo cardiac surgery has more risk than others, because of specific cardiovascular effects of the anesthetic drugs and the preoperative state of these patients, so the hemodynamic stability is very important in these patients. It seems that midazolam have less cardiovascular side effects than thiopentone. In this study, the effects of midazolam and thiopentone on cardiovascular system were compared. Materials and methods: Sixty patients in ASA class 2,3 that underwent coronary artery bypass grafting were randomly divided into two groups, all patients were pretreated similarly. Anesthesia induction was performed by a bolus injection of midazolam (0.25 mg/kg)in first group and thiopentone (5 mg/kg) in second group, and succinylcholine (1.5mg/kg) in both groups. Their trachea were intubated. Heart beat rate and arterial blood pressure were measured in following times: before (base) and after anesthesia induction, during intubation and 3, 5 and 8 minutes after intubation. Findings: The data showed that administration of both drugs decreased blood pressure during induction of anesthesia and changed heart beat rate minimally. However after intubation, blood pressure and heart beat rate increased in both groups. But, midazolam had less effects than thiopentone. Conclusions: Hemodynamic effects of midazolam is similar to thiopentone. Midazolam is a water-soluble, safe and effective inductive anesthetic with short- term effects, much lesser venous irritation, and it can be used instead of thiopentone in patients with cardiac diseases or those patients which thiopentone is contraindicated for whom.