摘要
目的 比较不同剂量的连续性静脉 静脉血液滤过 (CVVH) ,连续性静脉 静脉血液透析(CVVHD)及连续性静脉 静脉血液透析滤过 (CVVHDF)对各种溶质清除率的影响 ,以及理论推测与计算溶质清除率值之间的差异。方法 选择确诊为急性肾功能衰竭患者 5例 ,采用PRISMA机器行前稀释型连续性肾脏替代治疗 (CRRT) ,测定不同透析液及置换液流量下尿素氮 (UN)、肌酐 (Cr)、尿酸(Ua)、磷 (P)及 β2 微球蛋白 (β2 M)的清除率。结果 不同流量下测得的CVVH和CVVHD对小分子清除率计算值与理论推测值之间呈非常显著线性相关 (P <0 .0 0 1)。相同流量下 ,CVVH对 β2 M清除效果好 ,而CVVHD对尿素氮、肌酐、尿酸及磷清除效果好。在CVVHDF中测得的溶质清除率较相应流量的CVVH及CVVHD清除率之和要小。结论 理论推测公式基本反映不同流量下CVVH、CVVHD对小分子溶质的实际清除率 ,CVVH、CVVHD对大、小分子溶质的清除各有所长 ,临床可据此来确定不同CRRT模式及剂量。
Objective To study the solute clearance during various forms of continuous renal replacement therapy(CRRT) and test the formulas that allow the prediction of the influence of dialysate and ultrafiltration flow rate on small solute removal during CRRT. Method Five patients with acute renal failure were included in the study and were treated by venovenous CRRT using the PRISMA predilution system. Solute clearance of urea nitrogen(UN), creatinine(Cr), uric acid(Ua), phosphate(P) and β 2 microglobulin(β 2 M) were evaluated during CRRT with different dialysates and ultrafiltration flow rates. Results The determined clearance of small molecular solutes during continuous venovenous hemofiltration(CVVH) and continuous venovenous hemodialysis(CVVHD) was similar with the following formulas:K UF =(Q UF /60)×Q B/(Q B+Q UF /60) (in CVVH), Kd=Q D/60 (in CVVHD), where K is the clearance, Q B, Q D and Q UF are blood, dialysate and ultrafiltration flow rates, respectively. There was very significant correlation between calculated values of K UF and observed clearances of small solutes such as UN, Cr, Ua and P during CVVH, between calculated values of Kd and observed clearances of UN, Cr, Ua but not P during CVVHD( P <0.001). Clearances of UN, Cr, Ua and P during CVVHD were greater than those during CVVH, but clearance of β 2 M during CVVHD was less than that during CVVH. Interaction between convection and diffusion was found during continuous venovenous hemodiafiltration(CVVHDF). Conclusions The previous formulas can provide with the prediction of the clearance of small molecular solutes during CVVH and CVVHD. The present results demonstrate that diffusion is more efficient in removing small solutes than convection but less efficient in removing large solutes than convection. There is interaction between convection and diffusion during CVVHDF.
出处
《中华内科杂志》
CAS
CSCD
北大核心
2001年第3期183-186,共4页
Chinese Journal of Internal Medicine
