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Background:Propofol is a most widely used intravenous anesthetic drug. One of its most common complications is the pain upon injection; therefore, different methods, with various effects, have been proposed in order to alleviate the pain.Objectives:This study investigates the effects of paracetamol, ondansetron, granisetron, magnesium sulfate and lidocaine drugs on reducing the pain of propofol injection during anesthetic induction. Also, the hemodynamic changes will be analyzed.Patients and Methods:This is an interventional study containing 336 patients underwent elective orthopedic surgeries in Educational Hospitals of Mashhad University, using systematic sampling, the patients were divided into six groups. A 20-gauge needle was inserted into a venous vessel in the back of the hand and 100 cc of Ringer serum was injected into the vein, which was applied proximal to the injection site. Afterwards, paracetamol 2 mg/kg (group p), magnesium sulfate 2 mmol (group M), ondansetron 4 mg (group O), granisetron 2 mg (group G), lidocaine 40 mg (group L) and 5 cc saline (group S) were injected into the vessel, after 60 seconds, the tourniquet was opened. One quarter of the total dose of propofol (2.5 mg/kg) was injected with a flow rate of 4 mg/sec and then the injection pain was measured. Finally, the fentanyl (2 µg/kg), atracurium 0.5 mg/kg, and the remaining dose of propofol were injected and the vital signs were recorded before the administration of propofol and 1, 3, 5 and 10 minutes after the propofol injection.Results:The six groups did not significantly differ, regarding their gender, weight or age. Propofol injection pain was less in L and G groups, in comparison with the others (P ≤ 0.001). By analyzing the hemodynamic changes, it was observed that the least amount of change in mean arterial pressure was observed in the paracetamol group.Conclusions:The reduction of propofol injection pain was observed by using medications (in comparison with normal saline), but it was more significant in groups G and L. Moreover, Hypotension was higher in groups S and G and it was lessened in group P.

Background: Postoperative cognitive decline is a common complication observed frequently after general anesthesia in the immediate postoperative phase. We studied the effects of dexmedetomidine versus midazolam during coronary artery bypass graft (CABG) surgery on cognitive and memory function.  Methods: In this clinical trial, 42 elective on-pump CABG candidates under general anesthesia, aged between 40 and 65 years, were enrolled randomly in 2 groups. Group A received 0.05–0.1 mg/kg of midazolam and Group B received 1 µg/kg of dexmedetomidine. One day before surgery, all the participants underwent the Persian version of the Mini-Mental State Examination (MMSE) and the Persian version of the Wechsler Memory Scale (WMS) test for a comparison of cognitive impairment and memory functions. Both groups were given fentanyl and propofol for the induction of anesthesia and muscle relaxants. The MMSE and WMS tests were repeated 5 and 30 days after surgery. Results: The mean±SD of age was 55.47±7.18 y in Group A and 55.39±6.08 y in Group B. Eighty percent of the participants were men in both groups. There were no significant differences between Group A and Group B in the MMSE and WMS before surgery (89.04±14.30 vs. 97.10±18.10, respectively;  P=0.059), but the WMS was significantly different 30 days after surgery (87.60±14.30 vs. 103.53±19.93, respectively; P=0.005). Group A showed high cognitive impairment and low WMS scores compared with Group B (P=0.005). Additionally, the MMSE results were not statistically different between the 2 groups postoperatively (24.80±3.18 vs. 23.55±4.18, respectively; P=0.394). Conclusion: Our results showed that dexmedetomidine might have a lower impact on cognitive function than might midazolam among patients undergoing CABG.   J Teh Univ Heart Ctr 2019;14(2):67-73   This paper should be cited as: Rajaei M, Tabari M, Soltani G, Alizadeh K, Nazari A, Noroozian M, Morovatdar N. Dexmedetomidine and Midazolam on Postoperative Cognitive Impairment after Coronary Artery Bypasses Graft Surgery: A Randomized Clinical Trial. J Teh Univ Heart Ctr 2019;14(2):67-73.

BackgroundDirect laryngoscopy and tracheal intubation can result in blood pressure and heart rate increase which in turn may lead to myocardial ischemia, cerebral hemorrhage, and even death in susceptible patients. Tizanidine is α2-receptor agonists that suppresses central sympathetic system.ObjectivesThis study evaluates the effects of oral Tizanidine on hemodynamic responses during operations and aims to determine the appropriate Propofol dosage to maintain anesthesia under BIS monitoring.Materials and MethodsA double-blind clinical trial has been performed on 70 candidates for elective abdominal surgery undergoing general anesthesia in Educational Hospital of Ghaem, Mashhad, Iran. 35 randomly selected patients (the case group) were given 4 mg of oral Tizanidine 90 minutes before the induction of anesthesia whereas the remaining subjects (the control group) were given placebo. Blood pressure and heart rate before and after induction of anesthesia, and after intubation and extubation, existence of postoperative shivering, and the needed Propofol dosage were measured and recorded. Data analysis was done with T-test and Chi-squared test, using SPSS software version 16.ResultsVariations of blood pressure and heart rate after anesthesia induction, intubation and extubation were less in Tizanidine group generally. Postoperative shivering was reported in 28.6% and 11.4% of patients in control and case group respectively. Average propofol needed dose for anesthesia maintenance in case group was 25% less than the needed amount in the control group.ConclusionsUsing oral Tizanidine as a premedication, yielded stability in blood pressure and heart rate during surgery and decreased required Propofol. Considering its short duration of action, Tizanidine use as a premedication is recommended for sedation and stabilization of hemodynamic responses during the operations.

Background:Hypoxia occurs during one-lung ventilation (OLV) due to the arteriovenous shunt of unsaturated pulmonary venous blood. Hypoxic pulmonary vasoconstriction (HPV) acts as a defense mechanism against shunting. In thoracic surgery, anesthetics with minimal inhibitory effect on HPV and minimal hemodynamic changes are preferred.Objectives:The present study aimed to evaluate the effects of propofol and isoflurane on patients’ arterial oxygen pressure following one-lung ventilation during thoracic surgeries.Materials and Methods:In this randomized clinical trial study which was conducted in Iran, sixty patients with ASA (The American Society of Anesthesiologists) class I & II who were candidates for right elective thoracotomy were divided in two groups. Induction of anesthesia in the two groups was conducted using the same method, and left double-lumen endotracheal tube was inserted. In the first group propofol was used for the maintenance of anesthesia, and isoflurane for the second group. During two-lung ventilation and at minutes 5 and 10 after OLV, ABG (arterial blood gas) (for detecting the mean pressure of arterial oxygen), mean arterial pressure and heart rate were recorded.Results:Sixty patients (mean age = 4124.18 ± 18.63 years) were divided into two groups. The age and gender of the subjects were not statistically different between the two groups. In the propofol group, the arterial oxygen pressure during two-lung ventilation and at 5th and 10th minutes after OLV was 263.14 ± 136.19, 217.40 ± 133.99 and 182.34 ± 122.39; in the isoflurane group, it was reported as 206.29 ± 135.59, 164.78 ± 118.90 and 155.35 ± 109.21 mmHg, respectively. In the propofol group, mean arterial pressure during two-lung ventilation, and 5th and 10th minutes after OLV, was 84.01 ± 20.67, 88.15 ± 20.23 and 86.10 ± 19.13, respectively; regarding the isoflurane group, it was reported as 79.66 ± 17.04, 84.78 ± 20.19 and 86.50 ± 17.07 mmHg, respectively. In the propofol group, heart rate during two-lung ventilation, and 5th and 10th minutes after OLV was 92.77 ± 17.20, 94.0 ± 18.34 and 94.33 ± 21.03, respectively; In the isoflurane group, it was reported as 92.87 ± 16.96, 91.8 ± 18.75 and 91.05 ± 17.20 min, respectively. These values were statistically similar in the two study groups.Conclusions:The effects of propofol on hemodynamics and arterial oxygen pressure during one- or two-lung ventilation were not different from those of isoflurane.