Engdahl O, Boe J, Sandstedt S
Department of Anesthesiology, Central Hospital, Växjö, Sweden.
Reg Anesth. 1993 Nov-Dec;18(6):374-7.
The purpose of this investigation was to study the arterial plasma concentrations of bupivacaine and the hemodynamic changes after interpleural injection of 20 ml 0.5% bupivacaine with epinephrine in patients treated by chest drainage for spontaneous pneumothorax.
Twenty-two patients with spontaneous pneumothorax planned to be treated by chest drainage were randomly allocated to a bupivacaine group and a control group receiving saline. After introduction of the chest drain and evacuation of the pneumothorax, 10 injections through an interpleural catheter were given at 8-hour intervals in a double-blind fashion. Plasma concentrations were determined at 5, 10, 20, 30, 240, and 480 minutes after the first injection and before and at 15 and 30 minutes after the 4th, 7th, and 10th injections. Heart rate and mean arterial pressure was registered before and at 15 and 30 minutes after each injection.
Mean Cmax after the first injection was 1.02 +/- 0.24 microgram/ml at 15 minutes, the highest individual Cmax after 20 minutes being 1.56 micrograms/ml. Mean plasma concentrations increased up to and after the 4th injection but did not rise further after the 7th and 10th injections. The highest individual Cmax was 1.92 micrograms/ml at 15 minutes after the 10th injection. The injections were accompanied by a small but statistically significant reduction in mean arterial blood pressure and a rise in heart rate 15 minutes after injection in the bupivacaine group compared with the control group.
Repeated interpleural bolus injections of 20 ml 0.5% bupivacaine-epinephrine at 8-hour intervals are safe regarding plasma concentrations of bupivacaine. Small but statistically significant hemodynamic changes can be noticed, probably the result of beta- adrenergic stimulation by epinephrine.
本研究旨在探讨胸腔闭式引流治疗自发性气胸患者时，经肋间注射20毫升0.5%布比卡因加肾上腺素后动脉血浆布比卡因浓度及血流动力学变化。
22例计划行胸腔闭式引流治疗的自发性气胸患者随机分为布比卡因组和生理盐水对照组。置入胸腔引流管并排出气胸后，以双盲方式每隔8小时经肋间导管注射10次。于首次注射后5、10、20、30、240和480分钟以及第4、7和10次注射前及注射后15和30分钟测定血浆浓度。记录每次注射前及注射后15和30分钟的心率和平均动脉压。
首次注射后15分钟平均Cmax为1.02±0.24微克/毫升，20分钟时个体最高Cmax为1.56微克/毫升。第4次注射时及注射后平均血浆浓度升高，但第7和10次注射后未进一步升高。第10次注射后15分钟个体最高Cmax为1.92微克/毫升。与对照组相比，布比卡因组注射后平均动脉血压有小幅但具有统计学意义的下降，且注射后15分钟心率升高。
每隔8小时重复经肋间大剂量注射20毫升0.5%布比卡因-肾上腺素，布比卡因血浆浓度方面是安全的。可观察到有小幅但具有统计学意义的血流动力学变化，可能是肾上腺素β-肾上腺素能刺激的结果。
