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Objective Anesthesia may be required to ensure the immobility of the patient during a magnetic resonance imaging (MRI) scan, particularly in pediatric patients. An MRI scanner generates radiofrequency radiation (RFR) to obtain images of parts of the body. During an MRI procedure, an amount of RFR is transformed into heat by the body, thereby leading to increased body temperature. However, patients are at increased risk of hypothermia due to the impairment of thermoregulation by anesthesia and the cold and dry environment of the MRI room. The aim of this study was to investigate the effects of anesthesia on body temperature with regard to patient safety in pediatric patients undergoing an MRI scan. Materials and methods The study included a total of 40 children aged three to 10 years who underwent an MRI procedure. The patients were divided into two groups based on the administration of anesthesia: (I) non-sedated and (II) sedated. Prior to the procedure, non-sedated patients were informed about the procedure by a psychiatrist. Body temperature was measured from the tympanic membrane and skin in each patient. The MRI scan was performed at room temperature (20°C-22°C) with a relative humidity of 35%-40%. Results No significant change was found between pre- and post-scan body temperatures in Group I, whereas a significant decrease was found between pre- and post-scan body temperatures in Group II. No complication occurred in any patient due to temperature change or anesthesia. Conclusion A significant decrease in body temperature was found in pediatric patients undergoing an MRI procedure under sedation. The results implicated that anesthesia has a remarkable effect on the balance between the temperature increase caused by RFR and the temperature decrease caused by anesthesia.
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OBJECTIVE: Pseudocholinesterase (PChE) is an enzyme responsible for the hydrolysis of succinylcholine. In case of its deficiency, the effect of succinylcholine that is approximately 5-10 min is prolonged up to few hours. The use of succinylcholine has been declined recently. However, it is still actively used in some special conditions and in developing countries. In this study, incidence of PChE enzyme deficiency around Adiyaman city was investigated and presented with the literature review. METHODS: After obtaining an approval from the investigational board of our hospital (Adiyaman University Medical School, Biomedical Research Ethics Board, 30.12.2012, Nr: B.30.2.ADY.0.20.00-600/51), patients undergoing any elective operation under general anaesthesia in the Adiyaman University Medical School Hospital between March and December 2013 were recruited for the study. After obtaining the patients' written consents, blood PChE, alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea, creatinine, international normalisation ratio (INR) and activated partial thromboplastin time (aPTT) values of the patients were analysed. Possible association of the PChE deficiency with other values was also investigated. The normal value of PChE was taken as 4260-11250 for females aged 16-40 years and 5320-12920 U L(-1) for other patients. RESULTS: The study was completed with 964 patients, 702 (72.8%) of whom were females. PChE enzyme levels were under the normal in 7.2% of the patients. There were no correlation between patient group, ALT, INR, aPTT and creatinine elevation with PChE deficiency (p>0.05), whereas AST and urea level elevation was significantly associated with PChE deficiency (p<0.05). The risk of PChE deficiency was 4.5 and 9 times higher in the patients with the elevation of AST and urea levels, respectively. CONCLUSION: Pathological elevations of AST and urea that are a part of normal pre-operative biochemical analysis of blood will indicate the possible deficiency of PChE enzyme.
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OBJECTIVE: Ischemia and reperfusion injury due to tourniquet application during arthroscopy is a well known problem. This study aimed to compare the effects of dexmedetomidine and ketamine on hemodynamic and respiratory variables and on total anti-oxidant status (TAS), total oxidant status (TOS) and malondialdehyde (MDA) as markers of ischemia-reperfusion injury. MATERIALS AND METHODS: This study was approved by a local ethics committee. The study was performed on patients undergoing arthroscopic operation under spinal anesthesia. Thirty patients were randomized into two groups: Group D (dexmedetomidine; n=15) and Group K (Ketamine; n=15). Spinal anesthesia at the L2-4 level was achieved using a 25G spinal needle with hyperbaric bupivacaine at a dose of 12-15 mg in all patients. In Group D, patients were sedated with dexmedetomidine at a dose of 0.3-0.5 µg/kg/h, while Group K received ketamine at a dose of 1-1.5 mg/kg/h. Hemodynamic parameters, oxygen saturation, Ramsey sedation scale (RSS), and TAS, TOS, and MDA levels were recorded. RESULTS: Demographic parameters, TAS, TOS and MDA levels were similar between groups. In Group K, the TOS levels after tourniquet removal were significantly lower than at baseline and during the use of the tourniquet. Preoperative hemodynamic and respiratory variables were similar in both groups. Blood pressure values were decreased compared to baseline but these decreases were not statistically significant. CONCLUSION: In patients undergoing arthroscopy under spinal anesthesia, dexmedetomidine had effects similar to ketamine, led to insignificant alterations in hemodynamic and respiratory variables during surgery and had comparable effects on ischemia-reperfusion injury. Thus, we think that dexmedetomidine can be a safe alternative to ketamine as an intraoperative sedative.
