Impact of Two Different Types of Sedation on ICEB
Condition: Propofol; Dexmedetomidine; Electrophysiological Balance Index; QT Interval, Variation in; Tp-e Interval; QT Dispersion; Knee Osteoarthritis
MeSH terms: Osteoarthritis; Osteoarthritis, Knee
Study type: Interventional

Summary: 
      The QT interval is a measure of the combination of cardiac depolarization and repolarization
      as it encompasses both the QRS complex and the J-T interval. QT, QTc, QTd prolongation or
      shortening has been associated with ventricular arrhythmias . In order to define
      non-torsogenic drug-induced arrhythmias, the index of cardio-electrophysiological balance
      (iCEB), which is a new marker calculated with the QT/QRS formula, has been defined. In our
      study, we planned to evaluate the effects of dexmedetomidine and propofol on cardiac
      electrophysiology with all these parameters, especially the newly defined iCEB.
    

Detailed description: 
      Seventy patients who underwent operation under regional anesthesia and received
      intraoperative sedation will be included in the study. The patients will be divided into two
      groups, Group D (dexmedetomidine) and Group P (propofol). Sedative agent infusion will be
      started immediately after spinal anesthesia is administered. Preoperative ASA (American
      Society of Anesthesiologists) scores, demographic data, comorbidities and medications used
      will be recorded. Vitals and ECG prior to spinal anesthesia will be recorded. After that,
      spinal anesthesia will be applied and vitals and ECG will be recorded at 1, 5, 10, 15, 45 and
      75 minutes. The sedation levels of the patients will be measured noninvasively by bispectral
      index (BIS) monitoring. Patients will be kept within the limits of light sedation. The
      maximum dose of 1.4 micrograms/kg/hour in the dexmedetomidine group (group D, n=35) and 4.5
      milligrams/kg/hour in the propofol group (group P, n=35) will not be exceeded. The following
      parameters were set as the safety endpoint during sedation:

        -  Respiratory rate ≤8

        -  SpO2; 95

        -  Heart rate; 40

        -  Systolic blood pressure;80 At these endpoints, the patient's sedation dose will be
           reduced regardless of the BIS value.

      During sedation, patients will be given 3 liters of nasal oxygen per minute, which can be
      increased according to need. Just before and 1st, 5th, 10th, 15th, 45th, 75th minutes after
      spinal anesthesia systolic arterial pressure, diastolic arterial pressure, mean arterial
      pressure,peak heart rate, oxygen saturation, bispectral index, QT time, QTc, QT distribution,
      Tpe, iCEB will be evaluated.
    

Intervention name(s): Sedation with propofol; sedation with dexmedetomidine
Intervention type(s): Other; Other
Intervention description(s): After spinal anesthesia, patients will be sedated with propofol.; After spinal anesthesia, patients will be sedated with dexmedetomidine.
Intervention MeSH terms: Dexmedetomidine; Propofol
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment