The effect of anesthesia generated by medetomidine-ketamine and propofol-fentanyl combinations on some hemodynamic parameters and CNT-i and cerum CRP concentrations

The aim of this study was to determine the effect of anesthesia generated by medetomidine-ketamine and propofol-fentanyl combinations on some hemodynamic parameters and cTn-I and cerum CRP concentrations. The study performed on 9 female, 15 male total 24 New Zealand rabbits aged 1 to 3 years and weighting between 2-4 kg. Rabbits were divided randomly into two groups including 12 rabbits as medetomidine-ketamine (MK group) and propofol-fentanyl (PF group) groups. In MK group anesthesia induced with 20 mg/kg iv ketamine 5 seconds later administeration of 0.1 mg/kg iv medetomidine. In the PF group anesthesia induced with propofol at a dose of 10 mg/kg iv and the maintained with a constant rate infusion of propofol 1.3 mg/kg/min iv. Fentanyl calculated at the dose of 8 µg/kg iv and half of the dose used at the begining and the other half administered atd 30th minute of the maintaince. The righting, pedal withdrawal and ear pinching reflexes between induction and recovery time evaluated. The datas recorded at pre-anesthesia, induction (0 minute) and 5th, 10th, 15th, 30th, 45th and 60th minutes after induction including body temperature, heart rate, respiratory rate, oxygen saturation, sistolic and diastolic blood pressures. Mean arterial pressure calculated with the formula ([2Diastolic+Sistolic]/3). The blood samples analysed for the biochemical parameters (CRP and cTnI) that taken at the time of preanesthesia, induction anda ter 6, 12 and 24 hours of anesthesia. ECG recorded in second derivation before, during and 6, 12 and 24 hours after induction and duration and amplitude of P and T waves, duration and amlitude of QRS complex, duration of PQ and QT intervals were evaluated. Apnea appeared at 10 animals subsequent to induction in MK group, 4animals subsequent to induction and in vary times within infusion in PF group. Spontaneous breathing turned back in a few time. Respiratoy rate decreased considering to baseline and was statistical significant. Oxygen saturation was statistical significant for both group at the beggining time (0 minute). And the difference at the same time was significant in favour of PF whan compared the groups. The differences of body temperature was not significant. Mean arterial pressures decreased according to baseline in MK group and the differences in 5th, 10th, 15th, 30th and 45th minutes were statistical significant. In PF group differences in 5th, 10th, 15th, 30th, 45th and 60th minutes were statistical significant but difference between the compared groups were not statistical significant. Heart rate in 5th, 10th, 15th, 30th, 45th and 60th minutes for MK decreased according to baseline and was significant. In the time intervals of 0, 5, 10, 15, 30, 45 and 60 minutes the differences decreased in favour of MK group and were statistical significant. During and after the anesthesia changes at the heart ritm were recorded at both groups. These includes sinus tachycardia, multiple ventricular premature contractions, SA block, bradicardia, paroxysmal atrial tachycardia, AV block in medetomidine-ketamine group; tachycardia, multiple premature contractions and bradycardia according to SA block in propofol-fentanyl group. The CRP levels at 12th hour for both groups showed differences acording the baselines. The values of cTnI in 6th and 12th hours in MK group increased according the baseline and these differences were significant. In PF the values of cTn-I in 6th and 12th hours were decreased significantly when compared with MK group. As a result in this study its judged that to detect early myocardial damage associated with anaesthesia the cardiac troponins can be used at experimantal studies and clinical patients. Key Words: Cardiac Troponin-I, CRP, Medetomidine, Ketamine, Propofol, Fentanyl, Rabbit