Clinical research on the application of flushing strategy during colonoscopy

doi:10.16139/j.1007-9610.2026.02.07

Abstract

Abstract:

Objective To investigate the impact of different flushing strategies on procedure time and polyp detection rate(PDR) during colonoscopy. Methods A multicenter prospective controlled study was conducted, enrolling 248 patients who underwent colonoscopy at three hospitals from 2023 August to 2024 January. The patients were assigned to research group and control group randomly. The research group received a thorough flushing strategy during colonoscopy, while the control group received a limited flushing strategy. Clinical data, endoscopic procedure time, and polyp detection results were recorded and compared between the two groups. Results A total of 248 patients were enrolled, with 125 in the research group and 123 in the control group. Baseline characteristics were comparable between the two groups. The research group demonstrated a significantly higher PDR compared to the control group (P<0.01). Among patients with detected polyps, the research group detected more small polyps in the left colon than the control group (P<0.05). Conclusions The flushing strategy during colonoscopy improves PDR and increases the detection of small polyps in the left colon without prolonging the total procedure time.

Key words: Colonoscopy, Bowel preparation, Flushing, Polyp detection rate(PDR), Quality control

CLC Number:

R473.5

ZHANG Yajing, TAO Yifan, PAN Tong, TAO Dingxia, DAI Yancheng, ZHAO Hang. Clinical research on the application of flushing strategy during colonoscopy[J]. Journal of Surgery Concepts & Practice, 2026, 31(02): 137-143.

Figures/Tables 6

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References 20

[1]	KAWAMURA T, SEKIGUCHI M, TAKAMARU H, et al. “Endoscopic” adenoma detection rate as a quality indicator of colonoscopy: first report from the J-SCOUT study[J]. Dig Endosc, 2023, 35(5):615-624. doi: 10.1111/den.v35.5 URL
[2]	JACOBSON B C, ANDERSON J C, BURKE C A, et al. Optimizing bowel preparation quality for colonoscopy: consensus recommendations by the US multi-society task force on colorectal cancer[J]. Gastroenterology, 2025, 168(4):798-829. doi: 10.1053/j.gastro.2025.02.002 pmid: 40047732
[3]	KIM S H, KIM O Z, YOO I K, et al. Second examination of the right colon using narrow-band imaging increases adenoma detection rates in the right colon: a multicenter, randomized controlled trial[J]. J Gastroenterol Hepatol, 2025, 40(7):1667-1674. doi: 10.1111/jgh.v40.7 URL
[4]	TSENG C W, HSIEH Y H, KOO M, et al. Comparing right colon adenoma detection rate during water exchange and air insufflation: a double-blind randomized controlled trial[J]. Tech Coloproctol, 2022, 26(1):35-44. doi: 10.1007/s10151-021-02537-1
[5]	KALTENBACH T, GAWRON A, MEYER C S, et al. Adenoma detection rate (ADR) irrespective of indication is comparable to screening ADR: implications for quality monitoring[J]. Clin Gastroenterol Hepatol, 2021, 19(9):1883-1889. doi: 10.1016/j.cgh.2021.02.028 URL
[6]	ZHAO S, WANG S, PAN P, et al. Magnitude, risk factors, and factors associated with adenoma miss rate of tan-dem colonoscopy: a systematic review and meta- analysis[J]. Gastroenterology, 2019, 156(6):1661-1674. doi: 10.1053/j.gastro.2019.01.260 URL
[7]	SHAHINI E, SINAGRA E, VITELLO A, et al. Factors affecting the quality of bowel preparation for colonoscopy in hard-to-prepare patients: evidence from the literature[J]. World J Gastroenterol, 2023, 29(11):1685-1707. doi: 10.3748/wjg.v29.i11.1685 URL
[8]	LIU W Q, SHU L, ZHOU X, et al. Evaluation of the efficacy of polyethylene glycol in combination with different doses of linaclotide in a fractionated bowel preparation for colonoscopy: a prospective randomized controlled study[J]. Int J Colorectal Dis, 2024, 39(1):143. doi: 10.1007/s00384-024-04718-4
[9]	中华医学会消化内镜学分会结直肠学组. 结肠镜检查肠道准备专家共识意见(2023, 广州)[J]. 中华消化内镜杂志,2023, 40(6):421-430.
	Colorectal Group, Digestive Endoscopy Branch of Chinese Medical Association. Consensus on bowel preparation for colonoscopy (2023, Guangzhou)[J]. Chin J Dig Endosc,2023, 40(6):421-430.
[10]	KASTENBERG D, BERTIGER G, BROGADIR S. Bowel preparation quality scales for colonoscopy[J]. World J Gastroenterol, 2018, 24(26):2833-2843. doi: 10.3748/wjg.v24.i26.2833 URL
[11]	FAVERI M C, SOUZA D, ZUNIGA I, et al. Enhanced instructions for inpatients undergoing colonoscopy: a systematic review and meta-analysis of randomized controlled trials[J]. J Surg Res, 2025,314:229-239.
[12]	NIEDERMAIER T, AMITAY E L, GIES A, et al. Impact of inadequate bowel cleansing on colonoscopic findings in routine screening practice[J]. Clin Trans Gastroenterol, 2020, 11(4):e00169. doi: 10.14309/ctg.0000000000000169 URL
[13]	BHURWAL A, RATTAN P, SARKAR A, et al. A comparison of 9-min colonoscopy withdrawal time and 6-min colonoscopy withdrawal time: a systematic review and meta-analysis[J]. J Gastroenterol Hepatol, 2021, 36(12):3260-3267. doi: 10.1111/jgh.v36.12 URL
[14]	徐起, 宫爱霞, 张经文, 等. 退镜时间对结肠息肉检出率影响的研究[J]. 中华消化内镜杂志, 2019, 36(12):936-938.
	XU Q, GONG A X, ZHANG J W, et al. Effect of withdrawal time on colon polyp detection rate[J]. Chin J Dig Endosc, 2019, 36(12):936-938.
[15]	BRONZWAER M E S, GREUTER M J E, BLEIJENBERG A G C, et al. Impact of differences in adenoma and proximal serrated polyp detection rate on the long-term effectiveness of FIT-based colorectal cancer screening[J]. BMC Cancer, 2018, 18(1):465. doi: 10.1186/s12885-018-4375-9 pmid: 29695244
[16]	PARK S H, HONG K I, PARK H C, et al. Colonic polyp study: differences in adenoma characteristics based on colonoscopy history over 5-year follow-up period[J]. J Clin Med, 2024, 14(1):194. doi: 10.3390/jcm14010194 URL
[17]	JUNG Y, CHA J M, LEE N H, et al. Impact of endoscopists' personality traits on adenoma and polyp detection rates in colonoscopy: a kasid multicenter study[J]. Dig Dis Sci, 2020, 65(8):2302-2310. doi: 10.1007/s10620-020-06158-w
[18]	NG S, SREENIVASAN A K, PECORIELLO J, et al. Polyp detection rate correlates strongly with adenoma detection rate in trainee endoscopists[J]. Dig Dis Sci, 2020, 65(8):2229-2233. doi: 10.1007/s10620-020-06049-0
[19]	FACCIORUSSO A, BUCCINO V R, TONTI P, et al. Impact of fellow participation on colon adenoma detection rates: a multicenter randomized trial[J]. Gastrointest Endosc, 2020, 92(6):1228-1235. doi: 10.1016/j.gie.2020.05.015 pmid: 32433915
[20]	HASSAN C, SPADACCINI M, IANNONE A, et al. Performance of artificial intelligence in colonoscopy for ade-noma and polyp detection: a systematic review and meta-analysis[J]. Gastrointest Endosc, 2021, 93(1):77-85,e6. doi: 10.1016/j.gie.2020.06.059 URL

	Research group （n=125）	Control group (n=123)	Statistical value	P value
Age (years)	57.7±12.7	54.6±13.3	1.893	0.059 6
Sex				0.075 0
Male	72（57.6）	56（45.5）
Female	53（42.4）	67（54.5）
Source
Outpatient	75（60.0）	84（68.3）		0.187 4
Inpatient	50（40.0）	39（31.7）		0.187 4
Examination（%）
symptoms	49（39.2）	47（38.2）		0.069 1
screening	52（41.6）	64（52.0）
follow-up	24（19.2）	12（9.8）
Chronic disease
Yes	21（16.8）	25（20.3）		0.515 9
No	104（83.2）	98（79.7）		0.515 9
Colonoscopy history
Yes	37（29.6）	24（19.5）		0.077 1
No	88（70.4）	99（80.5）		0.077 1
BBPS	7.8±0.6	7.7±1.1	0.406 7	0.685 7

Item	Research group （n=125）	Control group (n=123)	t value	P value
Total procedure time（s）	847.9±454.4	779.5±358.7	1.314	0.190 1
Cecal intubation time（s）	316.0±240.0	303.5±199.3	0.445	0.657 1
Withdrawal time（s）	532.0±227.8	476.0±174.1	2.169	0.031 0
Number of segments with fluid pooling	4.0±0.9	3.78±1.04	1.933	0.054 4
Volume of irrigation fluid uesd（mL）	180.6±124.9	97.4±47.0	6.924	<0.000 1
BBPS	7.9±0.7	7.8±0.6	0.8118	0.417 7

Item	Research group （n=125）	Control group (n=123)	t value	P value
Number of patients with polyps	90（72.0）	34（27.6）		<0.01
Number of polyps found（per case）	2.2±1.8	1.9±1.0	0.8831	0.378 9
Single	40(32.0）	14(11.4)		0.840 0
Multiple	50(40.0)	20(16.3)
Morphology(total number of cases）				0.559 3
Ⅰ	27（21.6)	8(6.5)
Ⅱ	49(39.2)	22(17.9)
Ⅲ	13(10.4)	3(2.4)
Ⅳ	22(17.6)	5(4.1)
Location of the polyp				0.252 8
Right colon	35(28.0)	19(15.4)
Left colon	61(48.8)	21(17.1)
Number of patients with small polyps	52(41.6)	18(14.6)		0.687 0
Number of small polyps found				>0.999 9
Single	15(12.0)	5(4.1)
Multiple	37(29.6)	13(10.6)
Morphology of the small polyps				0.803 4
Ⅰ	14(11.2)	5(4.1)
Ⅱ	35(28.0)	14(11.4)
Ⅲ	6(4.8)	1(0.8)
Ⅳ	11(8.8)	2(1.6)
Location of small polyp				0.032 3
Right colon	16(12.8)	12(9.8)
Left colon	40(32.0)	9(7.3)