The Effects Of Remifentanil Infusion At Different Rates In Older Patients Undergoing Abdominal Region Surgery

Backgrouds and Objective With the aging of the population in our country, Anesthesiologist has paid more and more close attention to the old patients' anesthesia, especially the medicine deliver in anesthesia.The construction and function of the autonomic nerve system and cardiovascular system are all experiencing aging cataplasis in the aged people, therefore, the physical ability is attenuate in adjusting and adapting the blood circulatory fluctuation in the elder. During the anesthesia and operation, if the drug dosage is not appropriate, stress and cardiovascular responses would be controlled insufficiently, there will be a significantly hemodynamic fluctuation even result in cerebrovascular accident. So, the drug diliver in the elder should be more precise and esay to be controlled.At present, the use of opioids is regarded as an important measure to decrease the stress and cardiovascular reponses during the total intravenous anesthesia. Remifentanil, a new opioids, has the qualities of powerful potency, providing a titratable analgesic with rapid onset and rapid offset. It is suitable to be used in older patients during induction and maintenance of anesthesia.Remifentanil is metabolised by nonspecific esterases in blood and other tissues. The esterase-based metabolism of remifentanil makes its pharmacokinetics independent of end-organ failure. The pharmacokinetics of remifentanil are unaltered in patients with documented hepatic or renal failure. But age is an important factor which effect on the pharmacokinetic and pharmacodynamic parameters of remifentanil. It has been reported that bolus doses should be halved...