Bowel preparation protocol for hospitalized patients ages 50 years or older: A randomized controlled trial

Table 5 Comparison of laboratory test results before and after bowel preparation between groups 1 and 2

Variables, before and after bowel preparation	Group 11, n = 51	Group 22, n = 53	P value
Serum potassium in mmol/L	0.277 ± 0.288	0.275 ± 0.343	0.809
Serum sodium in mmol/L	1.804 ± 2.498	1.566 ± 2.508	0.878
Serum calcium in mmol/L	0.015 ± 0.117	0.018 ± 0.099	0.435
Serum creatinine in µmol/L	1.678 ± 6.110	3.832 ± 6.805	0.093
Plasma BNP in pg/mL	3.851 ± 30.264	8.0417 ± 64.987	0.216

Data are mean ± SD. BNP: B-type brain natriuretic peptide.

¹Group 1: 30 mL of lactulose on the day before the colonoscopy, three meals with a low-residue liquid diet, and 2 L of water mixed with polyethylene glycol on the colonoscopy day.

²Group 2: Regular diet for breakfast and lunch fasting or a low-residue liquid diet for dinner, and 2 L of water mixed with polyethylene glycol (PEG) on the day before the colonoscopy; 2 L of water mixed with PEG on the colonoscopy day.