مقایسه اثر پروپوفول و تیوپنتال بر سطح نوراپی‌نفرین قبل و بعد از لارنگوسکوپی در حین بیهوشی

Responses to painful stimulus are associated with broad range of physiological changes in human body. One of these significant responses is an increase in plasma norepinephrine level that may cause different systemic effects like coronary spasm, hypercoagulation, demand/supply ratio imbalance in myocardium, etc. Many clinical trials have tried to eliminate or decrease these changes by using different drugs and increasing depth of anesthesia. In this clinical trial study, the effects of two drugs of propofol and thiopental on norepinephrine level during laryngoscopy were studied. 60 ASA I patients, candidated for elective surgery under general anesthesia in the range of 15 to 45 years old, were randomly allocated to two groups. BIS monitoring was performed to measure depth of anesthesia. For all of the patients midazolam was administered as a premedication to reach BIS 70, then blood sampling was done. Thiopental was injected to one group and propofol to the other to reach BIS 40. Atracurium (0.5mg/kg) and fentanyl (3mcg/kg) was administered to both groups and intubation was done. Second blood sampling was done 3 minutes later. Norepinephrine level was measured in two stages: one as basal level and the other after laryngoscopy via ELISA method. Data showed that plasma norepinephrine level was 0.236±0.125 (mean±SD) after laryngoscopy in propofol group and 0.216±0.118mcg/dl (P=0.534). in thiopental groups. There was no significant statistical difference between two groups (P>0.05) therefore, it can be concluded that clinical decision for selection of drugs is only based on patient condition, drug side effects and cost–benefit ratio but not the type of drug itself.