The effect of perioperative use of dexmedetomidine on hemodynamic parameters and surgical response in chronic hypertensive patients

The aim of this study was to observe the effects of perioperative use dexmedetomidine on hemodynamic changes and endocrine parameter which can be affected by surgical stres. Forty two chronic hypertensive patient undergoing abdominal or pelvic surgery, we allocated randomly into two groups. Anesthesia was applied with thiopental, vecuronium, fentanyl, and was maintained with sevoflurane (1.5%-2.5%) within N2O/O2 (65%-35%) in both groups. In group D (n:21) loading dose of dexmedetomidine (1 µg /kg witin 10 min) was given to the patients 10 min before induction, and anfusion with the dose of 0,5 mcg/kg/h) was started together with anesthetic induction until the end of operation. In control group (group K, n:21) saline was given with the similar protocol as applied to the patient of group D. Additional fentanyl was given to patients when mean arterial blood pressure (MAP) has been increased more than 20% of baseline, and nitroglyserine was infused if hypertension can not be controlled with fentanyl alone. Hemodynamic parameters [systolic arteril blood pressure (SAP), diastolic arterial bood pressure (DAP), MAP, end-tidal carbon dioxide (ETCO2), heart rate (HR), pulse oxymetry (SpO2)] and additionally used fentanyl and nitrogliceryne were recorded. Venus blood samples were obtained from all patients for measurement of serum glucose, insulin, Growth Hormone, ACTH, Prolactin, cortisol levels at eight o?clock on the day of operation (t0, baseline), 10 min. after surgical incision (t1), postoperative 24th (t2) and 48th hours (t3) and were compared.SAP, DAP, MAP, and HR values were significantly lower in group D than in group K (p<0,05) during the operation. Additional fentanyl was given to 14 patients in group K, and to 7 patients in group D (p<005). The mean dose of additionally used fentanyl was 73,80± 68,22 µg in group K while it was 35,71±61,52 µg in grup D (p<0,05). All stres hormone, values were found to be increased in both groups compared to their baseline values. There was no statistically significant difference in serum glucose, insulin, growth hormone, ACTH and prolactin levels between two groups while serum cortisol levels were significantly lower in group D than in group K in measurements of t1,t2 and t3 (p<0,05). We conclude that perioperative infusion of dexmedetomidine may supress the response to surgical trauma, and may stabilize the hemodynamic changes in chronic hypertensive patients.