A case of life-threatening post-operative diffuse alveolar hemorrhage in patient with recent chemotherapy: A case report / 대한마취과학회지

A 53-year-old woman who had undergone total gastrectomy and received adjuvant chemotherapy two months ago underwent adhesiolysis of the small bowel. She presented with sudden desaturation and dyspnea of unknown etiology at postanesthetic care unit. Following ET intubation, the endotracheal tube suction revealed massive hemoptysis. Bilateral lung infiltrated on her chest radiograph and bronchofibroscopic examination disclosed a diffuse hemorrhage on both lung fields without bleeding focus. These findings were consistent with diffuse alveolar hemorrhage (DAH) syndrome. As per our knowledge and search, this is the first reported case of DAH that occurred during the recovery period immediately after general anesthesia. DAH is known to have a high mortality rate and an early detection followed by adequate treatment is essential.

The optimal concentration of siRNA for gene silencing in primary cultured astrocytes and microglial cells of rats / 대한마취과학회지

BACKGROUND: Small interfering RNAs (siRNAs) have been used to knockdown specific gene expression in various cells. Astrocytes and microglial cells play a key role in fundamental central nervous system functions and in chronic neuroinflammation. The aims of this study were to determine the optimal concentration of siRNA demonstrating efficient transfection and inhibition of gene expression via RNA interference (RNAi) and lower cytotoxicity, in primary cultured astrocytes and microglial cells of rats. METHODS: Astrocytes and microglial cells were isolated from the cerebral cortices of 2-day-old rats. Both the cells were transfected using transfection reagent (Lipofectaminetrade mark 2000), and fluorescein-labeled double-stranded RNA (dsRNA) or siRNA targeting green fluorescent protein. Transfection efficiency and cytotoxicity of dsRNA, and the degrees of RNAi induced by siRNA in these cells, were evaluated at various concentrations of RNA. RESULTS: Transfection efficiencies of dsRNA in both astrocytes and microglial cells were significantly higher (P < 0.05) at the concentrations of 20, 40, and 80 nM than at the concentrations of 0, 5, and 10 nM. There were no significant cytotoxicities within the applied concentrations of dsRNA (0-80 nM). The degrees of RNAi induced by siRNA were significantly higher (P < 0.05) at the concentrations of 5, 10, 20, 40, 80 nM, and 20, 40, 80 nM in astrocytes and microglial cells, respectively, compared with the control (0 nM). CONCLUSIONS: The siRNA concentration of 20 nM may be appropriate to induce RNAi in both astrocytes and microglial cells, while demonstrating low cytotoxicity, high transfection efficiency, and effective RNAi.

Rocuronium-induced neuromuscular block after long pretreatment of clonidine in rabbits / 대한마취과학회지

BACKGROUND: Clonidine, an alpha-2 adrenergic agonist, is used in the perioperative period and in intensive care for the management of hypertension. The in vivo and in vitro effects of clonidine on the actions of nondepolarizing neuromuscular blocking drugs are conflicting. We evaluated the potency and time course of rocuronium-induced neuromuscular block after prolonged pretreatment with clonidine in rabbits. METHODS: Sixty rabbits were randomly assigned to three groups; control (C) group: normal saline 0.1 ml/kg daily subcutaneous for 6 weeks; S3 group: clonidine 4 microgram/kg daily subcutaneous for 3 weeks; S6 group: clonidine 4 microgram/kg daily subcutaneous for 6 weeks. The dose-response relations of rocuronium were tested in 30 rabbits (10 from each of the three groups) during ketamine-thiopental anesthesia, while the time course of rocuronium 0.6 mg/kg was examined in 10 rabbits each from the three groups. RESULTS: There was no difference in mean arterial pressure and pulse rate among the experimental groups. The calculated ED(50) for rocuronium decreased significantly from 64.1 microgram/kg (C group) to 50.3 microgram/kg (S3 group) and 47.8microgram/kg (S6 group) (P < 0.001). There was no difference in the onset and the recovery times after rocuronium. CONCLUSIONS: Rocuronium after pretreatment with clonidine for three or six weeks may have an increased effect, but no difference in the duration of action compared with control group.