CVVHD时治疗剂量的计算.ppt

CVVHD时治疗剂量的计算,北京协和医院 杜 斌,内容,肾脏的生理功能,肾脏替代治疗 vs. 肾脏,heparin,V,V,PV,PA,high-flux,肾小球,原尿,肾小管,滤器剖面图,滤器清除物质的原理,超滤(ultrafiltration) 对流(convection) 弥散(diffusion) 吸附(adsorption),弥散作用的原理: 浓度梯度,半透膜两侧的溶质浓度梯度 溶质的移动 从浓度高的一侧向浓度低的一侧 浓度差消失时溶质的移动停止,弥散作用的原理: 浓度梯度,弥散作用的原理,弥散作用的原理: 溶质的清除,半透膜,血液,透析液,弥散作用的原理: 溶质的清除,半透膜,血液,透析液,弥散作用的原理: 逆流,半透膜,血液,透析液,弥散作用的原理: 透析液饱和度,透析液饱和度 Sd = dialysate / plasma,plasma,dialysate,弥散作用的原理: 弥散清除率,Kd = Sd.Qd = f (Qb, Qd, KoA),透析液饱和度 dialysate / plasma,影响溶质清除的因素,质量转运系数(Ko) 中空纤维对溶质的弥散阻力 溶质大小 滤器通透性 膜面积(A) 血流量(Qb) 透析液流量(Qd),溶质分子量与清除,Jeffrey RF, Khan AA, Prabhu P, et al. A comparison of molecular clearance rates during continuous hemofiltration and hemodialysis with a novel volumetric continuous renal replacement system. Artif Organs 1994; 18(6): 425-428,弥散作用的应用: 持续血液透析(CVVHD),V,V,PV,PA,low-flux,弥散作用的原理: 溶质的清除,0,40,80,120,10,102,103,104,105,urea,creatinine,Vit. B12,2-M,albumine,clearance ml/min,MW dalton,HD,Kidney,IL-1,TNF,IL-6,IL-8,弥散 vs. 对流,CVVH vs. IHD 清除效率,0,40,80,120,10,102,103,104,105,urea,creatinine,Vit. B12,2-M,albumine,clearance ml/min,MW dalton,HF,HD,Kidney,Cut-off,IL-1,TNF,Hrl (1996): Biocompatible membranes are linked with low incidence of infections, recovement of renal function and mortality in ARF,IL-6,IL-8,内容,CVVHD的剂量计算,V,V,PV,PA,low-flux,BWt 60 kg BFR = 150 ml/min RFR = 2400 ml/hr 平衡 = 0 ml/hr,流出液 = 2400 ml/hr 交换量 40 ml/kg/hr,影响溶质清除的因素: Qd,Qd, ml/min,Kurea, ml/min,KoA = 765 ml/min,Qb = 500,Qb = 450,Qb = 350,Qb = 250,Qb = 100,影响溶质清除的因素: KoA & Qb,Qb, ml/min,Kurea, ml/min,Qd = 500,KoA = 900,KoA = 700,KoA = 500,影响溶质清除的因素: MW,Qb, ml/min,Kd, ml/min,PMNA膜 KoA = 765 ml/min,尿素,肌酐,尿酸,VitB12,菊酚,内容,肾脏替代治疗的剂量: Ronco,Ronco C, Bellomo R, Homel P, et al. Effects of different doses in continuous veno-venous haemofiltration on outcomes of acute renal failure: A prospective randomised trial. Lancet 2000; 356: 26-30,ARF的治疗剂量: Kellum,“Patients with ARF should be treated with at least 35 mL/kg/h of hemofiltration/ hemodiafiltration or daily hemodialysis until or unless ongoing multi-center clinical trials show otherwise.”,肾脏替代治疗的原理,增加对流清除溶质能力的方法,增加UFR 提高跨膜压(TMP) 超滤液一侧的负压 血液一侧的正压 增加膜超滤系数(Lp) 增加滤器膜面积(A) 提高血流量(BFR) 采用前稀释方式 增加弥散清除,C = S.UFR = S.Lp.A.P,C = S.UFR.BFR / (BFR + RFR),KT = KD + UFR.S.(1 KD/BFR),弥散+对流的应用: 血液透析滤过(CVVHDF),V,V,PV,PA,high-flux,增加对流清除能力: 弥散 + 对流,总清除率,对流清除率,Clark WR, Ronco C. CRRT efficiency and efficacy in relation to solute size. Kidney International 1999; 56: S3-S7,增加对流清除能力: 弥散 + 对流,KT = KD + (UFR x Tr),S x (1 KD / BFR),弥散清除率(超滤= 0时),弥散+对流的原理,Kd = Kd0 + Tr x Quf Kd0 相同血流量及透析液流量而无超滤时的清除率 Tr 超滤率增加所致清除率增加的系数 Quf 0 85 ml/min时, Tr为0.4 0.52 Tr =