Friedrich L V, White R L, Brundage D M, Kays M B, Friedman R J
College of Pharmacy, Medical University of South Carolina, Charleston 29425-0810.
Pharmacotherapy. 1990;10(6):373-7.
Patients undergoing total knee arthroplasty were randomized to tourniquet inflation 1, 2, or 5 minutes after a 1-g dose of cefazolin. Serum, soft tissue, and bone samples were obtained at 10, 30, and 60 minutes after inflation, immediately prior to tourniquet release (PTR), and 5 minutes after release. Areas under the concentration-time curve (AUC10-PTR) were calculated using the linear trapezoidal method and normalized to actual body weight, creatinine clearance, and length of tourniquet inflation. The percentage of penetration was calculated using the normalized values for the respective AUCs. Differences among the groups were analyzed using analysis of variance or the Kruskal-Wallis test where appropriate. Groups were similar for age, actual body weight, duration of tourniquet inflation, and creatinine clearance (p greater than 0.05). The median percentages of penetration for soft tissue and bone at 5, 2, and 1 minute were 14.5% and 4.6%, 6.7% and 3.0%, and 5.9% and 4.6%, respectively. Only the percentage of soft tissue penetration between 5 and 1 minute was significantly different (p = 0.015). Gender and type of anesthesia (general, epidural) had no effect on cefazolin penetration into soft tissue or bone. Although increasing the time interval between cefazolin administration and tourniquet inflation resulted in higher soft tissue drug concentrations, a 1-minute interval resulted in soft tissue and bone cefazolin concentrations at or above the minimum inhibitory concentration for microorganisms likely to be encountered in this surgical procedure.
接受全膝关节置换术的患者在静脉注射1克剂量的头孢唑林后，被随机分为在1分钟、2分钟或5分钟后使用止血带的三组。在止血带充气后10分钟、30分钟和60分钟、即将松开止血带前（PTR）以及松开止血带后5分钟采集血清、软组织和骨样本。采用线性梯形法计算浓度-时间曲线下面积（AUC10-PTR），并根据实际体重、肌酐清除率和止血带充气时间进行标准化。穿透率百分比通过各自AUC的标准化值计算得出。在适当情况下，使用方差分析或Kruskal-Wallis检验分析组间差异。各组在年龄、实际体重、止血带充气时间和肌酐清除率方面相似（p大于0.05）。在5分钟、2分钟和1分钟时，软组织和骨的穿透率中位数分别为14.5%和4.6%、6.7%和3.0%、5.9%和4.6%。仅5分钟和1分钟时软组织穿透率百分比有显著差异（p = 0.015）。性别和麻醉类型（全身麻醉、硬膜外麻醉）对头孢唑林渗透到软组织或骨中没有影响。虽然增加头孢唑林给药与止血带充气之间的时间间隔会导致软组织药物浓度升高，但1分钟的间隔导致软组织和骨中的头孢唑林浓度达到或高于该手术中可能遇到的微生物的最低抑菌浓度。
