腹膜透析患者全身钾含量的测定。

Woodrow G, Oldroyd B, Wright A, Coward W A, Turney J H, Brownjohn A M, Truscott J G, Smith M A

Renal Unit, Leeds General Infirmary, UK.

Perit Dial Int. 2001;21 Suppl 3:S163-7.

OBJECTIVES

To assess the validity of measuring total body potassium (TBK) to estimate fat-free mass (FFM) and body cell mass (BCM) in patients on peritoneal dialysis (PD).

METHODS

We studied 29 patients on PD (14 men, 15 women) and 30 controls (15 men, 15 women). We calculated TBK by using a whole-body counter to measure 1.46 MeV gamma-ray emissions from naturally occurring 40K. We measured total body water (TBW) by deuterium oxide dilution, and extracellular water (ECW) from bromide dilution. These measurements allowed us to estimate intracellular water (ICW), fat-free mass dilution (FFM(Dilution)), and body cell mass dilution (BCM(Dilution)).

RESULTS

The FFM(TBK) in male PD patients (55.7 +/- 7.0 kg) did not differ from that in male controls (57.0 +/- 10.9 kg). The FFM(TBK) in female PD patients (38.4 +/- 6.8 kg) was less than that in female controls (44.7 +/- 4.5, p < 0.01). The FFM(Dilution) did not differ from the FFM(TBK). Correlation of FFM(TBK) and FFM(Dilution) was r = 0.90, p < 0.0001 for all subjects; r = 0.90, p < 0.0001 for PD patients; and r = 0.90, p < 0.0001 for controls. Bland-Altman comparison of FFM(Dilution) with FFM(TBK) in individuals showed bias 0.6 kg, range -8.5 kg to 9.7 kg for the whole group; bias 1.4 kg, range -7.9 kg to 10.7 kg for PD patients; and bias -0.2 kg, range -9.0 kg to 8.6 kg for controls. The BCM(TBK) in male PD patients (30.1 +/- 4.5 kg) did not differ from that in male controls (31.9 +/- 6.2 kg). The BCM(TBK) in female PD patients (19.0 +/- 4.4 kg) was less than that in female controls (23.1 +/- 2.9 kg, p < 0.01). The BCM(Dilution) results did not differ from those for the BCM(TBK). Correlation of BCM(TBK) and BCM(Dilution) was r = 0.90, p < 0.0001 for all subjects; r = 0.87, p < 0.0001 for PD patients; and r = 0.93, p < 0.0001 for controls. Bland-Altman comparison of BCM(Dilution) with BCM(TBK) in individuals showed bias 0.1 kg, range -5.9 kg to 6.1 kg for the whole group; bias 0.0 kg, range -6.9 kg to 6.9 kg for PD patients; and bias 0.1 kg, range -5.0 kg to 5.2 kg for controls. The [K+]ICW did not differ between PD patients and controls (148.0 +/- 25.1 mmol/L vs 148.1 +/- 14.3 mmol/L, p = nonsignificant).

CONCLUSIONS

Total body potassium is a valid, noninvasive technique for measuring FFM and BCM in PD patients. In our PD patient group, depletion of FFM and BCM as compared with controls was identified in the women but not in the men.

目的

评估测量全身钾（TBK）以估计腹膜透析（PD）患者无脂肪组织质量（FFM）和体细胞质量（BCM）的有效性。

方法

我们研究了29例PD患者（14例男性，15例女性）和30例对照者（15例男性，15例女性）。我们使用全身计数器通过测量天然存在的40K发出的1.46 MeVγ射线来计算TBK。我们通过氧化氘稀释法测量全身水（TBW），并通过溴化物稀释法测量细胞外水（ECW）。这些测量使我们能够估计细胞内水（ICW）、无脂肪组织质量稀释（FFM（稀释））和体细胞质量稀释（BCM（稀释））。

结果

男性PD患者的FFM（TBK）（55.7±7.0 kg）与男性对照者（57.0±10.9 kg）无差异。女性PD患者的FFM（TBK）（38.4±6.8 kg）低于女性对照者（44.7±4.5 kg，p<0.01）。FFM（稀释）与FFM（TBK）无差异。所有受试者中FFM（TBK）与FFM（稀释）的相关性为r = 0.90，p<0.0001；PD患者中r = 0.90，p<0.0001；对照者中r = 0.90，p<0.0001。个体中FFM（稀释）与FFM（TBK）的Bland-Altman比较显示，全组偏差为0.6 kg，范围为-8.5 kg至9.7 kg；PD患者偏差为1.4 kg，范围为-7.9 kg至10.7 kg；对照者偏差为-0.2 kg，范围为-9.0 kg至8.6 kg。男性PD患者的BCM（TBK）（30.1±4.5 kg）与男性对照者（31.9±6.2 kg）无差异。女性PD患者的BCM（TBK）（19.0±4.4 kg）低于女性对照者（23.1±2.9 kg，p<0.01）。BCM（稀释）结果与BCM（TBK）结果无差异。所有受试者中BCM（TBK）与BCM（稀释）的相关性为r = 0.90，p<0.0001；PD患者中r = 0.87，p<0.0001；对照者中r = 0.93，p<0.0001。个体中BCM（稀释）与BCM（TBK）的Bland-Altman比较显示，全组偏差为0.1 kg，范围为-5.9 kg至6.1 kg；PD患者偏差为0.0 kg，范围为-6.9 kg至6.9 kg；对照者偏差为0.1 kg，范围为-5.0 kg至5.2 kg。PD患者与对照者之间的[K + ]ICW无差异（148.0±25.1 mmol/L对148.1±14.3 mmol/L，p =无统计学意义）。