Tehran University Medical Journal

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Background: The electrothermal bipolar vessel sealing system is an adjunct to the hemostatic technique, which has been successfully used in many abdominal operation, recently made available to thyroid surgery. The purpose of this was compare the outcomes of new hemostatic technique with traditional method of clamp and tie.
Methods: In this retrospective cross-sectional study has been done in surgery's wards of Milad & Rasul- Akram hospitals in Tehran, Iran. During three- year period between 2005-2008 all patients with different kind of pathology that need operation were assessed. Time duration of surgery and hospital stay and post surgery complication in two group, ligasure (n=45) and clamp & tie (n=145) were compared with each others.
Results: No difference was seen between two groups in time duration of surgery. Significant difference was seen in hospital stay and complications of surgery. Time of operation in Ligasure group was 132/22 minute and in clamp and tie group was 130/10 minute. There was found significant difference in duration of hospital stay and postoperative complication. Hypocalcemia were seen in two and 24 cases in Ligasure and Clamp & Tie group, respectively (p<0.05). Hospital stay was 2.18 versus 2.65 day in ligasure and clamp & tie group, respectively (p=0.005).
Conclusions: Although Ligasure is easier than clamp & tie for surgeons but no reduction in time duration of surgery was seen in ligasure group. The advantages of this method in this study was reduction of hospital stay and complication.

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Background: Asthma is a life-threatening disease that can cause death due to bronchospasm. In addition to clinical symptoms such as wheezing, acute paroxysmal dyspnea, chronic cough after exposure to cold air or cough after exercise, spirometry is also necessary for the diagnosis of asthma. The association between respiratory symptoms and a positive methacholine challenge test (MCT) is still controversial. The aim of this study was to determine the association between methacholine test results and respiratory symptoms and allergy.

Methods: One hundred and forty-six patients with respiratory symptoms and normal baseline pulmonary function tests were enrolled in this cross-sectional study. The participants were divided into two groups according to their positive or negative response to MCT. The association between MCT and the clinical symptoms and allergy was later evaluated statistically.

Results: Out of 146 participants of the study 59 (40.4%) were female and 87 (59.6%) were male. The mean age of the participants was 33.8±13.8 years. Sixty-one patients (41.8%) had positive results for the test. There was an association between a history of allergy, wheezing and age with positive MCT results. The other clinical signs had no association with the test.

Conclusion: Methacholine challenge test is the best diagnostic test for ruling out asthma in patients with normal pulmonary function tests in whom we cannot definitely rule out asthma based solely on clinical symptoms. Nevertheless, in adults with a history of allergy, wheezing and also in patients below 30, the probability for a positive MCT is high.

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Background: It is generally accepted that the selective adenosine triphosphate-dependent potassium channel openers (KATP openers) have a dramatic role in the treatment of some cardiovascular disorders. The aim of this study was to investigate the effects of diazoxide, a potent ATP-related potassium channel opener, on spontaneously beating isolated rat atria to achieve more accurate approaches to treat cardiovascular diseases, such as atrial related disorders including atrial arrhythmias.
Methods: After induction of anesthesia, we exsected the heart and isolated the atria of 48 male Wistar rats. Later, we recorded the beating and contractile force of the atria by a physiograph. Subsequently, we studied the effects of diazoxide (2 to 100 µg/mL) on beating and contractile force of the isolated atria 5, 10, 15 and 20 minutes after applying the drug onto the atria.
Results: Diazoxide administration (2 to 100 µg/mL) showed a significant decrease (7% to 49% depending on concentration) in atrial beatings (P≤0.001) and in contractile force (1.5% to 67% depending on concentration), (P≤0.001). The effects began several minutes after applying the drug onto the tissues.
Conclusion: This study revealed that diazoxide has a direct concentration-dependent effect on cardiac performance and leads to reduction in beating rates and contractile force of the heart. This effect seems to be related to the activation of mitochondrial or sarcolemmal KATP channels. Since the inhibitory action of diazoxide on the heart was very remarkable and prompt, this agent may also exhibit antiarrhythmic properties.