The study, planned as randomized and prospective, was conducted in the operating room of Ankara Atatürk Training and Research Hospital after obtaining the permission of the Ethics Committee. Cooperating for laparoscopic cholecystectomy surgery, 60 adult patients with ASA classification of 1–2 and Mallampati score of 1–2 under general anaesthesia were included in the study after receiving informed and written consent. Patients with severe cardiac disease, obstructive and restrictive pulmonary disease, renal and hepatic insufficiency, a history of hypersensitivity to the agents to be used, pregnancy, psychiatric disorders, neurological disease history, a history of intracranial operations, a history of alcohol, sedative, tranquilizing and long-term analgesic use, and patients thought to have difficult intubation in direct laryngoscopy were excluded from the study.
No drugs for preoperative sedation were administered before the patients who were made to fast for at least 8 hours entered the operating room. The patients were divided into two groups for anaesthesia induction with pentothal or propofol according to a label randomly drawn from an envelope with 30 Group 1 (pentothal) and 30 Group 2 (propofol) labels. The demographic characteristics of the patients were recorded. The operation hours of all patients who were taken to the operation room were recorded. Routine anaesthesia monitoring (pulse oximetry, non-invasive blood pressure, ECG in standard D2 derivation, end-tidal carbon dioxide pressure (ETCO2) was performed on the patients who were placed on the operating table in the supine position. All patients were inserted a 20G intravenous (iv) cannula over the forearm to provide vascular access and their calculated maintenance was given as crystalloid. Before administering general anaesthesia, heart rate (HR), peripheral oxygen saturations (SPO2), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP) and end-tidal carbon dioxide pressure (ETCO2) values of all patients were recorded from the monitor.
The patients in both groups were made to inhale 100% oxygen for 3 minutes before induction and then general anaesthesia induction was initiated. Induction of the patients was performed with Lidocaine 1-1.5 mg/kg iv (Aritmal 2%, Osel), Thiopental 4–7 mg/kg iv (Pental sodium 0.5 gr, I.E. Ulugay), Remifentanil 1 mcg/kg iv (Ultiva 2mg GlaxoSmithKline) and Rocuronium 0.6–1.2 mg/kg iv (Esmeron 50mg, 5ml vial, Organon) in the first group, and Lidocaine 1-1.5 mg/kg iv, Propofol 2–3 mg/kg iv (Propofol 1%, Frenenius Container), Remifentanil 1 mcg/kg iv and Rocuronium 0.6–1.2 mg/kg iv in the second group.. . The patients were intubated endotracheally after waiting for sufficient time for sedation and paralysis. After endotracheal intubation, anaesthesia was set to 6–8 ml/kg, frequency 12 and FiO2 50%, but later changes were made to keep ETCO2between 30–36 and peak pressure below 30.
Soda-lime (Sorbo-lime, Berkim) was used as CO2 absorbent. The anaesthesia was maintained with remifentanil (0.05–0.25 mcg/kg/min) and 2–3% sevoflurane (Sevorane, Abbott Lab.) in a %40 O2-Air mixture. Additional doses were administered according to the surgical stress response criteria (tachycardia, increase in mean arterial pressure (MAP) (more than 20% increase compared to pre-anaesthesia), presence of tears, mydriasis, (+) light reflex) during the operation. Muscle relaxant maintenance was administered at a dose of 0.15 mg/kg.
Remifentanil infusion doses were adjusted so that the mean arterial pressure was above 60 mmHg in the patients. The heart rate was tried to be maintained provided that the heart rate did not change more than 30% compared to the initial values. A 30% decrease in MAP compared to the baseline value of hypotension was evaluated as a decrease in systolic blood pressure below 90 mmHg or a decrease in MAP below 55 mmHg, and hypotension was corrected by reducing the dose of remifentanil using iv fluids or vasoconstrictive agents (ephedrine). A decrease in the heart rate of the patients below 45 beats/min was considered bradycardia. 0.5 mg of Atropine iv was administered.
Anaesthesia and surgery times were calculated and recorded for each patient. At the end of the operation, recurarization was performed with intravenous 0.03–0.05 mg/kg neostipmine and 0.015 mg/kg atropine to antagonize the effect of the muscle relaxant after the spontaneous breathing of the patients returned. 1 mg/kg tramadol iv and Paracetamol 10–15 mg/kg iv were administered to the patients 30 minutes before the end of the operation.
The study was terminated in cases where the patient developed unexpected hypotension or bradycardia, had uncontrolled arrhythmias or arrhythmias affecting hemodynamics, or uncontrolled bleeding, and the operation could not be completed with laparoscopic surgery.
Before the induction of general anaesthesia (T0), after the induction of general anaesthesia (T1), after intubation (T2), 5 minutes after intubation (T3), 10 minutes after intubation (T4), 20 minutes after intubation (T5), 30 minutes after intubation (T6), 60 minutes after intubation (T7), 90 minutes after intubation (T8), after intubation (T9) and in the recovery room (T10), HR, SpO2, SAP, DAP, MAP and ETCO2 were recorded.
For the measurement of serum thiol-disulphide level, TOS (total oxidant status), TAS (total antioxidant status), PON1 (paraoxanase) and arylesterase levels, blood was taken twice from all patients - T0: once before the induction of general anaesthesia and T10: once in the recovery room. The venous blood samples of the patients taken into the routine biochemistry tube were centrifuged for 10 minutes at 3600 rpm in the biochemistry laboratory and then stored at -80 degrees. After all the samples were collected, they were all thawed at the same time and worked on in the Roche 501/701 modular system automatic analyser. Haemolyzed samples were excluded from the study.
STATISTICAL ANALYSIS
The research data were uploaded to the computer environment and evaluated via "SPSS (Statistical Package for Social Sciences) for Windows 22.0 (SPSS Inc, Chicago, IL)”. Descriptive statistics were presented as mean ± standard deviation, frequency distribution and percentage. Pearson Chi-Square Test was applied in the evaluation of categorical variables. The conformity of variables to normal distribution was examined using visual (histogram and probability graphs) and analytical methods (Shapiro-Wilk Test). Student's T Test was used as a statistical method for the statistical significance between the two independent groups for the variables that were found to match the normal distribution, and Paired Sample T Test was used as a statistical method between the two dependent groups. For variables that do not conform to the normal distribution; Mann-Whitney U Test was used between the two independent groups and Wilcoxon Signed Ranks Test was applied between the two dependent groups. The relationship between the variables was evaluated with the Spearman Test. The statistical significance level was accepted as p < 0.05.