残余肾功能状态对腹膜透析效能的影响

目的:前瞻性观察终末期肾衰(ESRF)患者在腹膜透析(PD)治疗后残余肾功能(RRF)对透析效能及相关临床指标之间的影响。方法:所有患者按残余肾小球滤过率(rGFR)水平将其分为A组(GFR0~2ml/min)、B组(GFR2·1~4ml/min)和C组(GFR>4ml/min)。每3个月进行一次临床随访,全面评估患者的全身情况及透析状态,包括血压、身高、体重、体重指数(BMI)、尿量(UV)、残余肾肌酐清除率(Ccr)、每周总尿素氮表现率(Kt/Vtotal)、每周肌酐总清除率(WCcrtotal)、蛋白氮呈现率(nPNA)、残余肾尿素及Ccr。对比观察不同RRF状态患者透析状况和部分临床及生化指标变化。尿量<100ml/d或Ccr<1·0ml/min视为无尿。结果:三组不同残肾状态患者Kt/vtotal和Ccr分别为1·75±0·35、2·07±0·54、2·46±0·50和53·4±11·2、66·6±11·2、97·6±22·1(L/Wks),各组之间差异非常显著(P<0·001)。三组不同残余肾Kt/v和Ccr分别占总体kt/v的12·4%、27%、45·7%及总体Ccr的18·3%、47·3%和65·3%,三组间相比差异亦显著(P<0·01)。此外,三组间高血压发生率、心胸比例及左心室肥厚(LVH)亦存在一定差异,C组心脏增大的病例明显低于A、B两组。RRF状态与透析效能呈正相关。本组患者除2例在透析治疗时即无尿,128例患者中有31例(24·2%)发生无尿,其中原发病为血管炎综合征及糖尿病肾病各占4例和7例,其无尿发生率分别占本病种的66·7%及25·9%;另20例无尿患者为肾小球肾炎或其它疾病,占此类疾病的20·6%。此外,发生无尿患者中有5例(16·1%)透析时尿量<300ml/d。结论:PD患者的残余肾仍然是清除体内代谢产物的重要途径,同时也影响血压及心血管系统并发症。

Influence of residual renal function on dialysis adequacy in patients with continuous ambulatory peritoneal dialysis

Objective:To evaluate the influence of residual renal function (RRF) on dialysis adequacy in patients with continuous ambulatory peritoneal dialysis (CAPD). Methodology:One hundred and thirty patients, who were initiated on CAPD between Oct 2002 and Jan 2006 and completed at least 6 months of CAPD, were enrolled in this study. 608 times of observation were performed in those 130 stable CAPD patients to determine the relationship between the RRF and dialysis adequacy. The residual GFR (rGFR), Urea Kt/V, creatinine clearance (Ccr), Cardiothoracic ratio and left ventricular end-diastolic diameter index (LVEDDI) was examined, and the influence of RRF on dialysis adequacy in PD patients was evaluated. According to the rGFR, all of patients were divided into three groups. The rRRF > 4ml/min were C group, 2-4 ml/min were B group, and <2 ml/min were A group. Results:There was a significant relationship between the RRF and the urea total Kt/V and total Ccr (r=0.62-0.84, P<0.05). Among three groups, the significant differences were observer in rRRF, total Ccr and total Kt/V (P<0.001). In C group, the percentage of rRRF contributing to clearance reached 45.7% of total Kt/V and 65.3% of total Ccr, and in B group, the percentage of rRRF contributing to clearance reached 27% of total Kt/V and 47.3% of total Ccr, while it was less than 20% of total Ccr and urea Kt/V in the A group (P<0.001). Among three groups, except the significant differences in rRRF, total Ccr and total Kt/V, there was also significantly different in the level of serum albumin and cardiothoracic ratio, respectively (P<0.001). However, there was no significant difference in blood pressure and LVEDDI. We found that patients with diabetes mellitus or lupus nephritis were associated with faster decline of rRRF. When the patients with urine volume less than 300ml/d would also be induced rRRF decreasing for short time. Conclusion: rRRF play a key role in maintenance of fluid balance, biochemical homeostasis and PD adequacy status. Therefore it must be keeping in mind that the dose and osmotic load of dialysis would be adjusted on patient's rRRF and body surface area.