Table 4.

Baseline characteristic comparisons among the three serum potassium level trajectories

Variable	Trajectory 1 (n = 3978)	Trajectory 2 (n = 557)	Trajectory 3 (n = 71)	p value
Baseline characteristics
Age, years	66.72 ± 9.98	69.35 ± 10.36	69.17 ± 11.53	< 0.001
BMI, kg/m2	30.15 ± 5.74	30.37 ± 6.41	29.66 ± 4.81	0.981
Male, n (%)	3111(78.21)	372(66.80)	46(65.00)	< 0.001
Laboratory parameters, mean ± SD
Hemoglobin, g/dL	9.85 ± 1.77	10.06 ± 2.36	10.57 ± 2.39	0.061
Platelet count, ×109/L	155.27 ± 51.64	176.88 ± 75.77	193.66 ± 95.49	< 0.001
White blood cell, ×109/L	13.07 ± 6.56	13.34 ± 6.12	14.09 ± 6.15	0.282
Lactate, mmol/L	2.16 ± 0.93	2.24 ± 1.44	2.03 ± 1.52	< 0.001
Blood glucose, mg/dL	120.78 ± 29.16	141.30 ± 58.32	151.74 ± 69.30	< 0.001
Vital Signs, mean ± SD
Heart rate, bpm	79.70 ± 10.23	83.27 ± 12.84	89 ± 18.81	< 0.001
Systolic blood pressure, mmHg	112.82 ± 16.82	111.56 ± 20.01	111.36 ± 20.70	0.031
Diastolic blood pressure, mmHg	59.05 ± 10.05	57.22 ± 11.54	57.41 ± 13.47	< 0.001
Mean arterial pressure, mmHg	77.44 ± 14.03	76.54 ± 22.35	78.11 ± 30.55	0.033
Respiratory rate, bpm	14.49 ± 5.26	16.40 ± 5.24	17.46 ± 5.64	< 0.001
Temperature, ℉	97.74 ± 3.11	97.97 ± 3.84	97.56 ± 7.78	< 0.001
Others, mean ± SD/n(%)
Death within 1- year	85(2.14)	44(7.90)	14(19.72)	< 0.001
Acute kidney injury	266(6.69)	176(31.60)	51(71.83)	< 0.001
ICU day	2.23 ± 2.75	5.39 ± 4.80	12.86 ± 12.74	< 0.001
Hospital day	7.65 ± 6.24	13.79 ± 7.43	23.87 ± 14.65	< 0.001
Ventilation hour, h	33.31 ± 36.16	88.75 ± 79.61	181.51 ± 162.88	< 0.001
SOFA	4.79 ± 2.34	5.51 ± 3.33	6.38 ± 3.71	< 0.001

The patients were divided into three groups according to the trajectory of changes in the serum potassium concentration. Trajectory 1: stability in the initial stage, Trajectory 2: stability in the middle stage, Trajectory 3: Continuous fluctuations