Yafteh

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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.

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Background: Intraoperative bleeding is one of the most important complications of surgery. Different techniques and methods have been used to decline this problem. In this study, the effect of oral preanesthetic clonidine on producing a bloodless surgical area was examined on patients undergoing tympanoplasty. Materials and Methods: A randomized, triple blind clinical trial was carried out 88 patients candidates for tympanoplasty. The patients were randomly divided into two groups. 44 patients received oral clonidine 300 µgr, 90min before arriving at the operating room, and 44 patients received placebo. The method of anesthesia was similar in both groups. Interaoperating bleeding assessed on a four –point scale from 3 (abundant bleeding) to 0 (no bleeding). Moreover, surgeon’s satisfaction in the field of surgery and the homodynamic changes were assessed and recorded in data collecting sheets. Results: There were no statistically significant differences regarding gender and age between two groups. The homodynamic changes in the group that had received clonidine were fewer in comparison with those in the control group. In addition, the bleeding amount in the group receiving clonidine was 54.6 times less than in the control group, and the surgeon,s satisfaction in the clonidine group was 54.6 times more than that in the control group. The statistical analysis using independent sample t test showed significant difference between these two groups. Conclusion: Oral clonidine as a premeditation reduces bleeding in tympanopalsty and improves surgeon’s satisfaction.