To examine the possibility that the dexmedetomidine-induced cerebral vasoconstriction deteriorates ischemic brain damage, we administered dexmedetomidine during transient focal cerebral ischemia in rats. Rats received intravenous infusions of dexmedetomidine at 0.1μg·kg-1·min-1, and 1μg·kg-1·min-1 during cerebral ischemia induced by the occlusion of the middle cerebral artery with a nylon suture. Further, 5mg·kg-1 of yohimbine combined with dexmedetomidine were also given during the cerebral ischemia. Cerebral infarction was detected in rats receiving infusions of dexmedetomidine at 0.1μg·kg-1·min-1 and 1μg·kg-1·min-11. Cerebral infarct volume was significantly larger in rats receiving dexmedetomidine infusion at 1μg·kg-1·min-1 than that of rats receiving at 0.1μg·kg-1·min-1. Treatment with yohimbine significantly decreased the dexmedetomidine-induced infarct volume by 84%. Therefore, it is suggested that the infusion of high-dose dexmedetomidine aggravates ischemic brain damage following focal cerebral ischemia in rats via the activation of alpha-2 adrenoceptor.
We report our experiences in use of a minimal incision with retroperitoneal approach for treatment of patients with abdominal aortic aneurysm(AAA) and arteriosclerosis obliterans(ASO) in the aortoiliac area. Between January 2000 and March 2002, nineteen consecutive patients with the AAA or ASO underwent operation with a minimal incision technique(<10cm, group M), were compared with 25 patients treated in the same time period with conventional incision(>20cm, group C). There were no significant differences in operation time and cross-clamping time. There was no hospital death in both groups. With the advantages of minimal skin incision, less abdominal muscle dissection, optimal aortic exposure, early resumption of ambulation and shorter hospitalization time, we believe that this technique is a safe and less invasive method for use in abdominal aortic surgery.
Blunt trauma to a subclavian artery can result in intimal tears and secondary thrombosis of the arterial lumen. We report a case of subclavian artery occlusion due to this mechanism. Arterial flow to the upper extremity was restored by axillo-axillary bypass grafting. This less invasive procedure may also decrease the morbidity and mortality as compared with that using thoracotomy or sternotomy.