Succinylcholine is a depolarising muscle relaxant that is used for rapid tracheal intubation in general anesthesia. It is a short-acting drug which is hydrolyzed by plasma cholinesterase. Some factors can decrease the activity of this enzyme in body. Some patients may have abnormal form of this enzyme that leads to prolonged duration of action and apnea. The subjects of this research were a male (55) and a female (57) who had prolonged apnea after administration of succinylcholine (4-8h), and they improved completely after mechanical ventilation.

  Background & Objectives: A common side effect associated with succinylcoline is postoperative myalgia. The pathogenesis of this myalgia is still unclear therefore there is no ideal method of decreasing the rate and severity of fasciculation and postoperative myalgia. The aim of this prospective and randomized study was to evaluate the influence of low-dose succinylcholine for tracheal intubation on the rate and severity of fasciculation and postoperative myalgia.

  Methods: In this study, 60 patients of ASA physical grading I or II were randomly entered into two groups of 30 patients each. One fasciculation was evaluated on the basis of Mingus and myalgia on the basis of Harvey Induction of anesthesia was performed with fentanyl/thiopentone, and then succinylcholine 1 mg/kg (control group) and 0.6 mg/kg (case group) were administered to patients for tracheal intubation.

  Results: There was not fasciculation in 50% (15 patients) of study group and on the rest no severe fasciculation occurred. Furthermore, the severity of fasciculation in the study group was significantly lower than that of control group (p<0.0001). In 16 (53.3%) patients of study group and 4 (13.3%) of control group myalgia were not occurred. Severity of myalgia was also significantly lower in study group than the control group (p<0.0001). Acceptable intubating conditions in all patients of two groups.

  Conclusion: Decreasing the dose of succinylcholine (from 1 mg/kg to 0.6 mg/kg) both provides acceptable intubation conditions, and reduces the rate and intensity of succinylcholine induced fasciculation and postoperative myalgia.

  Backgroud & Objective : Inducing of safe airway and rapid , is very important in the anesthesia of emergency patients and it reduces many complications because of delay in the endotrachal intubation .In this group of patients, administration of succinylcholin is a choice. But, this drug has serious complication, that is sudden increase of serum potassium level , and could cause cardiac arrest .So ,it is suggested, use of non blocker dose of non depolarizant neuromuscular blocker (defasciculation), for reducing this response . So , the aim of this study , was to determine the effect of pretreatment atracurium on serum potassium level associated with administration of succinylcholine .

  Methods: This study was performed clinical trial on 82 elective patients aged between 15 -70 years whit ASAI-II (American society of anesthesiology of physical status class)who where scheduled undergo operate general surgery. Premedication drugs are used to all patients , according to weight. and first blood sample was taken, considered as control group. then pretreatment atracurium injection (50mcg/kg) and after three minutes, was performed induction with thiopental sodium (5mg/kg) and succinylcholine (1.5 mg/kg ), and after 5 minutes , second blood sample was taken, test group . blood samples, were poured in the espicial tube of serum potassium and immediately , serums were separated . Then , potasiom level of serums were measured with micro light . The datas analyzed with statistical program ( spss) and then , were compared .

  Results: According to the obtained results , the mean of serum potassium level after administration of succinylcholine associated with defasciculation atracurium and before the administration of pretreatment atracurium (base level) was not different . It was not seen , a statistically significant difference between two groups, with attention to paired- t-test(p=0.936) and wilcoxon signed ranks test (p=0.594).

  Conclusion: Regarding the results of this study , administration of pretreatment atracurium is not effective in prevention of hyperkalemia induced by succinylcholin with attention base level.