Mehrotra R, Saran R, Moore H L, Prowant B F, Khanna R, Twardowski Z J, Nolph K D
Department of Internal Medicine, University of Missouri-Columbia 65212, USA.
Perit Dial Int. 1997 Sep-Oct;17(5):497-508.
To better define the targets for initiation of chronic dialysis, we compared the relationship between the normalized protein equivalent of nitrogen appearance (nPNA, g/kg standard weight/day) and weekly urea clearance (Kt) normalized to total body water (V) in predialysis chronic renal failure (CRF) patients and in patients on continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD). We also studied the relationships of other nutritional parameters to weekly Kt/Vurea in CRF patients.
This cross-sectional study was a prospective observational design meant to study each patient once.
The University Hospital and Clinics and Harry S. Truman VA Medical Center, Columbia, Missouri.
Forty-five consecutive predialysis CRF patients were enrolled and the results compared with patients on CAPD and HD.
In CRF, the nPNA calculated from urea appearance correlated with the weekly Kt/Vurea (r = 0.57, p < 0.0001) and, using exponential best-fit, nPNA = 1.217 x (1-e-0.769Kt/V). This exponential relationship was similar to that for CAPD and both were different from that in patients on HD. Likewise, nPNAs, calculated from Kjeldahl nitrogen output, and weekly Kt/Vurea were correlated (r = 0.37, p = 0.014) and, using exponential best-fit, nPNA = 1.102(1-e-0.867Kt/V), similar to the relationship in patients on CAPD. Evidence is presented that these relationships are not explained only by mathematical coupling. There was a significant correlation between the weekly Kt/Vurea and 24-hour urinary creatinine excretion.
The findings suggest that in CRF, as in CAPD, a weekly Kt/Vurea less than 2.0 is likely to be associated with a nPNA less than 0.9 g/kg standard weight. In CRF patients, initiation of chronic dialysis should be considered if weekly renal Kt/Vurea falls below 2.0 and a nPNA greater than 0.8 is desired.
为了更好地确定开始慢性透析的指标，我们比较了透析前慢性肾衰竭（CRF）患者、持续性非卧床腹膜透析（CAPD）患者和血液透析（HD）患者的标准化氮呈现蛋白当量（nPNA，克/千克标准体重/天）与以总体水（V）标准化的每周尿素清除率（Kt）之间的关系。我们还研究了CRF患者中其他营养参数与每周Kt/Vurea的关系。
这项横断面研究是一项前瞻性观察性设计，旨在对每位患者进行一次研究。
密苏里州哥伦比亚市的大学医院及诊所和哈里·S·杜鲁门退伍军人医疗中心。
连续纳入45例透析前CRF患者，并将结果与CAPD和HD患者进行比较。
在CRF中，由尿素生成量计算得出的nPNA与每周Kt/Vurea相关（r = 0.57，p < 0.0001），采用指数最佳拟合，nPNA = 1.217 x (1 - e-0.769Kt/V)。这种指数关系与CAPD患者相似，且两者均与HD患者不同。同样，由凯氏定氮法氮输出量计算得出的nPNAs与每周Kt/Vurea相关（r = 0.37，p = 0.014），采用指数最佳拟合，nPNA = 1.102(1 - e-0.867Kt/V)，与CAPD患者的关系相似。有证据表明这些关系并非仅由数学关联所解释。每周Kt/Vurea与24小时尿肌酐排泄之间存在显著相关性。
研究结果表明，在CRF中，与CAPD一样，每周Kt/Vurea低于2.0可能与nPNA低于0.9克/千克标准体重相关。在CRF患者中，如果每周肾脏Kt/Vurea降至2.0以下且期望nPNA大于0.8，则应考虑开始慢性透析。
