Wessén A, Persson P M, Nilsson A, Hartvig P
Department of Anesthesiology, University Hospital, Uppsala, Sweden.
J Clin Anesth. 1994 May-Jun;6(3):193-8. doi: 10.1016/0952-8180(94)90058-2.
To investigate the pharmacokinetics of propofol in combination with epidural anesthesia or with intravenous (i.v.) alfentanil infusion, and to investigate the clinical feasibility of this anesthetic technique in lower abdominal surgery.
Randomized, open clinical study.
Operating theaters and postanesthesia recovery unit at the department of gynecology of a university medical center.
20 healthy, consenting ASA physical status I and II adult female patients undergoing lower abdominal surgery.
A total i.v. anesthetic technique was used in all patients. In Group 1, a continuous infusion of propofol was combined with an epidural block with bupivacaine. Group 2 patients received a combination of propofol and alfentanil infusions.
The pharmacokinetics of propofol are best fitted to a two-compartment open model and were similar in both patient groups. Propofol blood clearance was 29.8 +/- 6.51 ml/min/kg, and volume of distribution was 3.60 +/- 1.34 L/kg, resulting in a blood elimination half-life of 144 +/- 46 minutes. The entire period of anesthesia was stable in the alfentanil group. In the epidural group, the initial period of anesthesia was too light as judged by the autonomic response to tracheal intubation, which also correlated in time to a lower propofol blood concentration than was seen in the alfentanil group. No evidence was found that an epidural block induced a change in propofol kinetics, apart from the lower blood concentration during the initial period of anesthesia.
We could not show any statistically significant influence of an epidural blockade on the pharmacokinetic parameters of propofol. Nevertheless, the concentration-time profile changed during infusion, rendering the described infusion regimen, in combination with epidural anesthesia, unsatisfactory for adequate hypnosis. The propofol infusion regimen combined with alfentanil provided immediate and stable blood concentrations that were adequate for surgery.
研究丙泊酚与硬膜外麻醉或静脉输注阿芬太尼联合使用时的药代动力学，并探讨这种麻醉技术在下腹部手术中的临床可行性。
随机、开放临床研究。
某大学医学中心妇科手术室及麻醉后恢复室。
20例接受下腹部手术、自愿参与的健康ASA身体状况I级和II级成年女性患者。
所有患者均采用全静脉麻醉技术。第1组，丙泊酚持续输注联合布比卡因硬膜外阻滞。第2组患者接受丙泊酚和阿芬太尼输注联合使用。
丙泊酚的药代动力学最适合二室开放模型，两组患者相似。丙泊酚的血浆清除率为29.8±6.51 ml/min/kg，分布容积为3.60±1.34 L/kg，血药消除半衰期为144±46分钟。阿芬太尼组整个麻醉期间平稳。硬膜外组，根据气管插管时的自主反应判断，麻醉初期过浅，且此时丙泊酚血药浓度低于阿芬太尼组，两者在时间上相关。除麻醉初期血药浓度较低外，未发现硬膜外阻滞引起丙泊酚动力学改变的证据。
我们未能显示硬膜外阻滞对丙泊酚药代动力学参数有任何统计学上的显著影响。然而，输注过程中浓度-时间曲线发生了变化，使得所述输注方案与硬膜外麻醉联合使用时，不能提供足够的催眠效果。丙泊酚输注方案联合阿芬太尼可提供即时且稳定的血药浓度，足以满足手术需要。
