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. 2023 Jun 29;18(10):1260–1271. doi: 10.2215/CJN.0000000000000228

Table 2.

Blood and urine results at baseline and during follow-up

Blood and Urine Values T0 T30 T60 T90 T120 T240 P Value versus Placebo P Value versus KCl
Plasma [K+] (mmol/L) Placebo 4.0±0.2 4.1±0.3 4.2±0.4 4.1±0.3 4.0±0.2 4.0±0.2
K-cit 4.0±0.2 4.5±0.4a 4.7±0.4a 4.6±0.3a 4.5±0.4a 4.1±0.3 <0.001 0.76
KCl 4.0±0.2 4.5±0.3b 4.7±0.3b 4.7±0.3b 4.6±0.4b 4.1±0.2 <0.001
K-cit+lis 4.0±0.3 4.7±0.5a 4.9±0.5a 4.8±0.4a 4.6±0.4a 4.2±0.3 <0.001 0.94
KCl+lis 4.0±0.2 4.5±0.3b 4.7±0.4b 4.7±0.4b 4.6±0.3b 4.3±0.3b <0.001
Plasma [Na+] (mmol/L) Placebo 141±2 140±2 140±2 140±2 140±2 140±2
K-cit 140±2 139±2 139±2 140±2 140±3 140±2 0.89 0.96
KCl 140±2 140±2 140±2 139±2 140±2 140±2 0.93
K-cit+lis 139±2 139±2 139±2 139±2 139±2 139±2 0.94 0.62
KCl+lis 140±3 140±2 139±2 139±3 139±3 140±2 0.71
Plasma [Cl−] (mmol/L) Placebo 104±2 104±2 104±3 103±2 104±3 103±3
K-cit 103±3 102±3 103±3 103±3 103±3 102±3 0.13 <0.001
KCl 103±2 103±2c 104±2b,c 104±2 104±2c 103±2c 0.02
K-cit+lis 103±2 103±3 103±3 103±2 103±3 103±3 0.81 0.02
KCl+lis 104±3 104±3 104±3 104±3c 104±3 104±3c 0.04
Plasma [HCO3−] (mmol/L) Placebo 27±3 27±2 27±2 28±2 27±2 28±2
K-cit 26±4 27±3 28±2 27±2 27±2 28±2 0.18 <0.001
KCl 26±3 26±2 26±3b,c 26±2b,c 26±2c 26±2b,c 0.004
K-cit+lis 26±3 27±2 28±2a 28±2 27±2 28±2 0.02 <0.001
KCl+lis 26±2 26±2c 27±2c 26±2b,c 26±2c 27±2b,c 0.01
Venous pH Placebo 7.37±0.02 7.38±0.02 7.38±0.02 7.37±0.02 7.37±0.03 7.36±0.02
K-cit 7.37±0.04 7.37±0.02 7.39±0.03a,c 7.39±0.02a,c 7.38±0.03c 7.37±0.02c <0.001 <0.001
KCl 7.37±0.03 7.37±0.02 7.37±0.03 7.36±0.02 7.36±0.02 7.35±0.02 0.10
K-cit+lis 7.37±0.03 7.38±0.02 7.39±0.03 7.38±0.03 7.38±0.02 7.37±0.02 0.06 <0.001
KCl+lis 7.38±0.03 7.38±0.03 7.36±0.2b,c 7.36±0.2b,c 7.36±0.2b,c 7.35±0.02b,c 0.002
Plasma aldosterone (ng/L)d Placebo 171 (74–235) 85 (74–157) 99 (82–144) 98 (61–181)
K-cit 119 (98–187) 277 (167–360)a 191 (136–280)a 127 (84–189) <0.001 0.99
KCl 133 (91–169) 248 (194–322)b 188 (143–305)b 136 (85–182) <0.001
K-cit+lis 93 (78–138) 175 (88–281)a 134 (80–302) 88 (69–160) 0.01 0.32
KCl+lis 96 (73–173) 165 (139–322)b 120 (104–178)b 120 (74–157) 0.001
RBC K+ (mmol×10−12) Placebo 8.5±0.7 8.8±0.7 8.6±0.7 8.8±0.7 8.4±0.5 8.4±0.5
K-cit 8.5±0.8 8.4±0.7 8.4±0.6 8.7±0.7c 8.7±0.7c 8.7±0.5 0.58 0.02
KCl 8.4±0.5 8.5±0.8 8.5±0.8 8.4±0.5 8.4±0.7 8.5±0.8 0.08
K-cit+lis 8.6±0.7 8.5±0.8 8.5±0.6 8.4±0.6 8.4±0.7 8.3±0.4 0.07 0.64
KCl+lis 8.4±0.8 8.4±0.6 8.7±0.7 8.5±0.7 8.4±0.5 8.2±0.4 0.17
Urine volume (ml) Placebo 63±45 203±163 104±64
K-cit 77±83 298±126a 103±50 0.02 0.31
KCl 75±74 259±147 103±60 0.15
K-cit+lis 70±38 302±162a 105±55 0.05 0.45
KCl+lis 62±35 235±89 118±73 0.21
Urine osmolality (mOsm/kg) Placebo 821±135 633±212 752±137
K-cit 810±168 596±144 789±138 0.88 0.43
KCl 801±152 649±188 777±156 0.36
K-cit+lis 768±175 591±167 759±153 0.58 0.63
KCl+lis 786±123 650±125 772±147 0.30
Urine potassium (mmol) Placebo 6±5 16±8 11±7
K-cit 7±8 36±11 20±7 <0.001 <0.001
KCl 7±5 28±12 16±6 <0.001
K-cit+lis 6±3 29±12 16±5 <0.001 0.50
KCl+lis 5±3 27±10 17±6 <0.001
TTKG Placebo 10±3 10±4 10±4
K-cit 10±4 14±4a 19±5a,c <0.001 0.007
KCl 9±3 12±3b 15±4b <0.001
K-cit+lis 10±4 12±4a 16±4a <0.001 0.47
KCl+lis 8±3 12±3b 14±3b <0.001
Urine pH Placebo 6.1±0.6 6.8±0.8 6.6±0.9
K-cit 6.2±0.7 7.7±0.3a,c 7.7±0.5a,c <0.001 <0.001
KCl 6.1±1.0 7.1±0.5 6.5±1.0 0.18
K-cit+lis 6.2±0.9 7.6±0.2a 7.3±0.6a,c <0.001 <0.001
KCl+lis 6.0±0.7 7.3±0.5b 6.6±0.8 0.02

The last two columns on the right side show the P value for the global null hypothesis; no difference at any time. In case of a P < 0.05, pairwise comparisons were performed with least significant difference post hoc test. Values are mean±SD. KCl, potassium chloride; K-cit, potassium citrate; lis, with lisinopril pretreatment; RBC, red blood cell; TTKG, transtubular potassium gradient; IQR, interquartile range.

a

P < 0.05 potassium citrate versus placebo.

b

P < 0.05 potassium chloride versus placebo.

c

P < 0.05 potassium citrate versus potassium chloride.

d

Values are median±IQR.