The Effect of BIS-guided Propofol Induction on the Peroperative and Postoperative Hemodynamic Response in Patients With Cardiac Risk in Ear-nose-throat Surgery.

Anesthesia induction will be started by monitoring ECG, non-invasive artery monitoring, peripheral oxygen saturation and BIS for all patients who are taken to the operating room without sedation. The patients were divided into 2 groups: Group P; Propofol 2 mg / kg bolus (in 10 seconds), Group B; Propofol will be started as an infusion dose of 0,25 mg / kg / min and will be discontinued when the BIS reaches a minimum value of 60. Noninvasive arterial blood pressure and heart rate will be measured at 2-minute intervals during the first 10 minutes of induction and then at 15th , 20th ,30th and 60th minutes peroperatively. Hypotension; mean arterial pressure (MAP) <60 mmHg, bradycardia heart rate <60 / min, hypertension MAP> 120 mmHg and tachycardia heart rate> 100 / min were defined. The difference of changes, their duration, the difference between the maximal value and the baseline value, and the number of occurrences of hypotension, hypertension, and arrhythmias during the entire induction and perioperative period will be recorded. Noninvasive arterial blood pressure and heart rate measurements of the patients will be made in the postoperative period at 5th , 15th , 30th minutes and at 1st , 2nd , 4th , and 24th hours. At the end of the 1st month, it will be questioned whether the patients encounter a cardiovascular problem that will require treatment or hospitalization in the period following the surgery. All patients will be started with 5 ml / kg / hour IV crystalloid infusion. When the MAP falls below 60 mmHg during induction, the patient will be given the Trendelenburg position and the crystalloid infusion will be increased to 10 ml / kg / hour, and vasoconstrictor drug will be added if the hypotension does not improve within the following 10 minutes.