Bisacodyl plus split 2-L polyethylene glycol-citrate-simethicone improves quality of bowel preparation before screening colonoscopy

Table 1 Characteristics of the two polyethylene glycol bowel preparations

	PEG-CS	4-L PEG
Active ingredients	Bisacodyl, PEG, citrates, simethicone	PEG, sodium sulphate
Product description	4 sachets; each containing PEG 4000 60.7 g, sodium citrate 1.066 g, citric acid 1.25 g, simethicone 80 mg	8 sachets; each containing PEG 4000 29.5 g and sodium sulphate 2.843 g
Total volume	2-L	4-L
Electrolytes	Sodium chloride, potassium chloride	Sodium bicarbonate, sodium chloride, potassium chloride
Osmolality (mOsmol/kg)	293	288
Mixed with	Water	Water
Diet prior to colonoscopy	Clear liquid after starting solution intake	Clear liquid after starting solution intake
Timing of intake	1-L of solution at 19:00 the day prior to procedure 1-L of solution at 7:00 the day of the exam	3-L of solution at 17:00 the day prior to procedure 1-L of solution at 7:00 the day of the exam
Additional agents	15 mg bisacodyl (3 tablets) at 16.00 the day prior to procedure

PEG: Polyethylene glycol; PEG-CS: PEG with citrates and simethicone.

Table 2 Primary efficacy and other endpoints n (%)

Outcome	BIS + 2-L PEG-CS (n = 138)	4-L PEG (n = 126)	P value
Bowel cleansing
A (all segments as excellent or good)	107 (77.5)	105 (83.3)	NS
B (at least one segment as fair)	21 (15.2)	11 (8.7)
C (at least one segment as poor)	7 (5.1)	8 (6.3)
D (exam not completed)	3 (2.2)	2 (1.6)
Successful (A + B)	128 (92.8)	116 (92.1)	NS
Unsuccessful (C + D)	10 (7.2)	10 (7.9)
Tolerability
Nausea	27 (19.6)	26 (20.6)	0.575
Bloating	11 (8.0)	33 (26.2)	< 0.001
Abdominal discomfort	13 (9.4)	5 (4.0)	0.079
Overall (any of previous ones)	45 (32.6)	57 (45.2)	0.035
Acceptance
Good	70 (50.7)	30 (23.8)	< 0.001
Satisfactory	55 (39.9)	67 (53.2)
Not acceptable	13 (9.4)	22 (23.0)
Compliance
100% of solution drunk	134 (97.1)	110 (87.3)	0.010
75% of solution drunk	4 (2.9)	15 (11.9)
50% or less of solution drunk	0 (0.0)	1 (0.8)

PEG: Polyethylene glycol; PEG-CS: PEG with citrates and simethicone; BIS: Bisacodyl.

Table 3 Quality of cleansing for each colonic segment

	Caecum/ascending colon		Transverse colon		Descending colon		Sigmoid colon		Rectum
	BIS + 2-L PEG-CS (n = 138)	4-L PEG(n = 126)	BIS + 2-L PEG-CS (n = 138)	4-L PEG(n = 126)	BIS + 2-L PEG-CS (n = 138)	4-L PEG(n = 126)	BIS + 2-L PEG-CS (n = 138)	4-L PEG(n = 126)	BIS + 2-L PEG-CS (n = 138)	4-L PEG(n = 126)
Score
Excellent	37.00%	52.40%	52.20%	57.90%	51.40%	59.50%	45.70%	60.30%	40.60%	51.60%
Good	50.70%	37.30%	38.40%	34.90%	37.00%	31.00%	39.90%	28.60%	43.50%	39.70%
Fair	7.20%	4.00%	5.10%	2.40%	6.50%	5.60%	9.40%	5.60%	12.30%	4.00%
Poor	2.90%	4.80%	2.20%	3.20%	5.10%	3.20%	5.10%	4.80%	3.60%	4.00%
Missing	2.20%	1.60%	2.20%	1.60%	0.00%	0.80%	0.00%	0.80%	0.00%	0.80%

PEG: Polyethylene glycol; PEG-CS: PEG with citrates and simethicone; BIS: Bisacodyl.