Hynynen M
Department of Anaesthesia, Helsinki University Central Hospital, Finland.
Acta Anaesthesiol Scand. 1987 Nov;31(8):706-10. doi: 10.1111/j.1399-6576.1987.tb02649.x.
Adsorption of fentanyl and alfentanil to the cardiopulmonary bypass (CPB) equipment was studied in vitro by adding one of the analgesics to the priming solution consisting of either saline or a mixture of saline and blood. Opiate concentrations in the solutions were measured during a 60-min circulation period of a closed CPB system. When the saline prime was used, 29% of the predicted fentanyl level of 30 ng ml-1 was found at the end of the experiment, while the recovery of alfentanil was 80% of the calculated level of 1500 ng ml-1. When blood was added to the prime, experiments with fentanyl produced similar results to those with pure saline prime, but recovery exceeding the calculated concentration was obtained with alfentanil. The difference between the alfentanil levels in the two primes may reflect the poor distribution of this analgesic into red blood cells. In another set of experiments, the CPB circuit was primed with fentanyl or alfentanil and circulated for 10 min before connection of the apparatus to patients undergoing cardiac surgery under high-dose opiate anaesthesia. This priming prevented the steep reduction in plasma opiate concentration regularly observed during the institution of CPB. It is concluded that in a clinically relevant dose range a smaller fraction of alfentanil is sequestered by the CPB apparatus than fentanyl.
通过将其中一种镇痛药添加到由生理盐水或生理盐水与血液的混合物组成的预充液中，在体外研究了芬太尼和阿芬太尼对体外循环（CPB）设备的吸附情况。在一个封闭的CPB系统60分钟的循环期间，测量溶液中的阿片类药物浓度。当使用生理盐水预充时，在实验结束时发现芬太尼水平为预测的30 ng/ml的29%，而阿芬太尼的回收率为计算水平1500 ng/ml的80%。当向预充液中添加血液时，芬太尼实验产生的结果与纯生理盐水预充时相似，但阿芬太尼的回收率超过了计算浓度。两种预充液中阿芬太尼水平的差异可能反映了这种镇痛药在红细胞中的分布较差。在另一组实验中，CPB回路用芬太尼或阿芬太尼预充，并在将设备连接到接受高剂量阿片类麻醉的心脏手术患者之前循环10分钟。这种预充防止了在建立CPB期间经常观察到的血浆阿片类药物浓度的急剧下降。得出的结论是，在临床相关剂量范围内，CPB设备隔离的阿芬太尼比例比芬太尼小。
