持续性血滤在心血管疾病伴急性肾衰中的应用

应用CAVH或VCCH技术求治12例多种心血管疾病引起心、肾功能衰竭，经药物治疗无效的患者。血滤治疗时间为4－72h不等，所有患者均有不同程度的症状改善：浮肿消减，心率下降，肺动脉压及肺毛细血管楔嵌压有所下降，心衰控制或部分控制；2例患者尿量恢复至500ml/24h以上，电解质人衡及酸中;下例血肌酐及血尿素氮水平下降。作者认为，持续性血液滤过技术是抢救各种不同原因心血管疾病造成心、肾功能衰竭的有效治疗方法，但疾病的最终转归主要取决于心脏功能的恢复，早期应用持续性血液滤过治疗效果较佳。     

连续动静脉血液滤过治疗危重病32例结果分析

本文应用连续动静脉血液滤过(CAVH)系列中的连续静脉静脉血液滤过(CVVH)及连续静脉静脉血液透析滤过(CVVH DF)治疗危重病人32例.结果表明,CAVH系列能有效地解除过度的水负荷,其平均超滤率达622ml/h,对血尿素氮、肌酐也有较好的清除,与治疗前相比,差异显著(P<0.01),而心血管并发症少.提示CAVH方法能较好地配合用于多器官功能衰竭等一类危重病的治疗.     

Pharmacokinetics and dosage of fluconazole in continuous hemofiltration (CAVH, CVVH) and hemodialysis (CAVHD, CVVHD)

Continuous haemofiltration (CAVH, CVVH) and haemodialysis (CAVHD, CVVHD) are increasingly used in patients with acute renal failure (ARF). The elimination rates of fluconazole vary considerably among the different procedures. In CVVHD, the elimination rate is, depending on the combined dialysate/ultrafiltrate flow rate, the most marked compared to CVVH and intermittent dialysis with a fluconazole clearance exceeding the values of healthy persons in CVVHD 2 L/h. To achieve therapeutic plasma levels during continuous renal replacement therapy, the same loading dose as in patients without renal failure should be applied, followed by the adjusted maintenance dose for anuric patients multiplied by a factor taking the extracorporeal elimination of the absorbed dose into account (CAVH, CVVH: x 2.2, ultrafiltrate flow 0.5 L/h; CAVHD, CVVHD: x 3.8, combined dialysate/ultrafiltrate flow 1.5 L/h). Despite the broad therapeutic margin of fluconazole, drug monitoring is recommended with respect to the very limited number of investigations with relatively low dosages up to 200 mg/day and--which is of paramount importance--to achieve therapeutic drug levels in vital indications.     

在ICU内实施连续动静脉血液滤过(CAVH)的护理

连续动静脉血液滤过是应用小型血液滤过器治疗急性肾功能衰竭的新技术,本文总结３７例ＩＣＵ内使用ＣＡＶＨ技术治疗急性肾功能衰竭病人的护理体会。认为,ＣＡＶＨ技术在控制高血压,迅速有效地清除水份、肌酐、尿素及中分子毒素等方面疗效显著,对心血管系统干扰小,方法简便,安全可靠,特别适合ＩＣＵ内危重病人并发急性肾功能衰竭的抢救。     

Clearance of imipenem/cilastatin in acute renal failure patients treated by continuous hemodiafiltration (CAVHD)

In patients with acute renal failure, who were treated with continuous arteriovenous hemofiltration (CAVH) or continuous arteriovenous hemodiafiltration (CAVHD), we measured clearance rates of imipenem and cilastatin (Tiënam-500^®). Literature data on volume of distribution and on the endogenous clearance in normals and in anuric patients and the observed clearance rates by CAVH/CAVHD were used to develop guidelines for dose adaptations. Based on the desired peak levels of imipenem, normal subjects should receive the fixed imipenem/cilastatin dose combination (500 mg/500 mg) q.i.d. and patients with acute renal failure should receive the same dose b.i.d. After starting treatment with either CAVH, CAVHD or continuous venovenous hemofiltration (CVVH), no further dose adjustment is necessary. The non-renal clearance rate of cilastatin is very low compared to that of imipenem. If a patient develops anuria, the clearance rate of imipenem decreases from the normal value of 245 ml/min to 116 ml/min. Clearance rate of cilastatin, however, decreases from 230 ml/min to 3 ml/min. Therefore, in patients with renal failure accumulation of cilastatin will occur. On the other hand, if the patient is treated by CAVHD, the relative contribution of the dialyser clearance to the total drug clearance is much greater for cilastatin than for imipenem. As a result, the accumulation of cilastatin is reversed. During treatment by CAVHD, the clearance rate of imipenem raises 15%–25% and that of cilastatin 335%–600%. For this reason, we conclude that the use of the fixed dose combination (500 mg/500 mg) b.i.d. in patients with acute renal failure treated by CAVHD may be justified.     

Changes of the Serum Amikacin (AMK) Level in Patients with Serious Acute Renal Failure Treated by Continuous Arteriovenous Hemofiltration (CAVH)

Abstract: This study clarified changes in the serum amikacin (AMK) levels in the blood of 5 patients (4 men and 1 woman; average age 59.2 ± 5.9 years) with serious acute renal failure treated by continuous arteriovenous hemofiltration (CAVH). The following principal results were obtained. (A) The average remaining rate of AMK in the blood after 6 h was 60.8 ± 5.3% and 50.4 ± 5.3% after 12 h. The average half-life period (t_1/2ß) of AMK in the blood during CAVH was 18.3 ± 3.4 h. (B) The remaining rate of AMK in the blood after 12 h correlated significantly with the blood urea nitrogen (BUN) level (r = 0.71, p < 0.05) and with the volume of urine excreted per day (r =-0.71, p < 0.05). (C) The average lowest AMK concentration after 24 h for a continuous 17-day period was 3.3 μ/ml. These results suggest that the administration of 100 mg of AMK once a day is useful and safe for patients with serious acute renal failure treated by CAVH and that it will not accumulate in the body.     

CAVH用于肾移植后体内水钠潴留的疗效观察

为观察连续性动静脉血液滤过(CAVH)用于肾移植后体内水钠潴留患者的疗效,对我院89例肾移植后体内水钠潴留患者行CAVH,使用床边P-21泵血滤机及膜面1.4 m~2聚砜膜透析器,使用低分子肝素抗凝,流速25～45mL/min。在血滤过程中,使用10％NaCl 10 mL,输白蛋白、全血、林格平衡液;监测心率、血压、液体出入量、细胞因子、移植肾功能、血气、胸片、电解质及酸碱平衡情况。追踪1～2年,78例(随防1年)、75例(随防2年)移植肾功能恢复良好,67例患者心功能及肺部通气功能改善,4例规律透析,11例死于多脏器衰竭。提示:应用CAVH可减少血容量,减轻细胞内外水肿,从而减轻移植肾、肺、脑水肿,从而改善移植肾的功能及肺泡通气功能;CAVH用于急诊重症患者是安全、有效和简便的。     

Single-dose kinetics of imipenem/cilastatin during continuous arteriovenous haemofiltration in intensive care patients

The single i.v. dose kinetics of a fixed combination of imipenem/cilastatin were investigated in ten critically ill patients treated by continuous arteriovenous haemofiltration (CAVH). Eight patients suffered from acute renal failure and two had normal renal function. Both drugs were measured in plasma and ultrafiltrate by high-performance liquid chromatography. While the pharmacokinetics of both drugs are almost identical in patients with normal renal function, we found the following dissociation of pharmacokinetic parameters in our patients with renal failure: for imipenem the total clearance and elimination half-life was 104 +/- 12 ml/min and 2.2 +/- 0.1 h, respectively, and for cilastatin 29 +/- 10 ml/min and 13.8 +/- 4.5 h. The pharmacokinetics of imipenem and cilastatin differ from each other in renal failure because imipenem, unlike cilastatin, undergoes marked elimination by non-renal pathways. Our results did not differ from previously reported data in healthy volunteers and patients with impaired renal function. Elimination of imipenem by CAVH was low (7% of the dose). As a consequence of the unsatisfactory non-renal clearance of cilastatin, however, the fraction of the dose removed by CAVH was significantly greater (approximately 30%) than that of imipenem. This did not, however, correct the dissociation of the pharmacokinetic profiles of the two drugs. In conclusion, the dose of imipenem/cilastatin in critically ill patients with renal failure treated by CAVH should be modified according to renal function but elimination by CAVH does not need to be considered.