Factors associating with oxygenation of lower-limb muscle tissue in hemodialysis patients

Table 1 Patients’ characteristics and the correlation between lower-limb muscle regional saturation of oxygen and clinical parameters in a simple linear regression analysis

	Mean ± SE	P values	r
Total number of patients (male/female)	67 (53/14)
Age (yr)	67.1 ± 1.2	0.09	-0.21
Disease
Diabetes mellitus	38
Chronic glomerulonephritis	14
Nephrosclerosis	4
Polycystic kidney disease	3
Others	8
HD duration (yr)	5.6 ± 0.9	0.02	-0.28
Systolic blood pressure (mmHg)	144 ± 3	0.97	-0.01
Diastolic blood pressure (mmHg)	75 ± 2	0.04	0.26
pH	7.39 ± 0.02	0.41	-0.10
pCO2 (mmHg)	36.9 ± 0.5	0.14	0.18
pO2 (mmHg)	85.6 ± 2.0	0.80	-0.03
HCO3- (mEq/L)	21.9 ± 0.3	0.70	0.05
SpO2 (%)	95.4 ± 0.3	0.88	-0.02
Hb (g/dL)	9.9 ± 0.1	0.30	0.13
Aterial O2 content (mL/dL)	12.9 ± 0.2	0.27	0.13
BUN (mg/dL)	51.4 ± 2.2	0.03	0.27
Cr (mg/dL)	8.4 ± 0.3	0.02	0.28
Na (mEq/L)	137.0 ± 0.4	0.19	0.16
K (mEq/L)	4.2 ± 0.1	0.02	0.30
Ca (mg/dL)	8.7 ± 0.1	0.91	-0.01
P (mg/dL)	4.5 ± 0.2	< 0.01	0.31
Total protein (g/dL)	6.1 ± 0.1	0.72	0.04
Serum albumin (g/dL)	3.2 ± 0.1	0.02	0.29
Serum osmolality (mOsm/kg•H2O)	301 ± 1	0.09	0.21
Plasma glucose (mg/dL)	156 ± 8	0.52	-0.08
Kt/V urea	1.18 ± 0.04	0.65	-0.06
Urea reduction ratio (%)	61.3 ± 1.6	0.94	0.01

SpO₂: Oxygen saturation; Hb: Hemoglobin concentration; BUN: Blood urea nitrogen concentration; Cr: Serum creatinine concentration; Na: Serum sodium concentration; K: Serum potassium concentration; Ca: Serum calcium concentration; P: Serum inorganic phosphate concentration; HD: Hemodialysis; SE: Standard error.

Table 2 Multiple linear regression analysis of independent factors of lower-limb muscle regional saturation of oxygen in hemodialysis patients

Parameters	Coefficient (95%CI)	Standardized coefficient	P values
P	3.02 (0.38-5.65)	0.27	0.025
Serum albumin	6.26 (0.15-12.37)	0.24	0.045

P: Serum inorganic phosphate concentration.