|Year : | Volume
| Issue : | Page :
Graphical education and appropriate time before elective colonoscopy make better bowel preparation
Jiachen Sun1, Yongpeng Chen1, Yuqin Gu2, Junrong Chen3, Chujun Li1, Qiulun Zhou2, Jiancong Hu4, Guozhi Jiang2
1 Department of Gastrointestinal Endoscopy, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
2 School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen, Guangdong Province, China
3 Department of General Practice, the Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
4 Department of Endoscopic Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
|Date of Submission||01-Nov-2021|
|Date of Acceptance||28-Feb-2022|
|Date of Web Publication||07-Jun-2022|
School of Public Health (Shenzhen), Sun Yat-sen University, No. 66 Gongchang Road, Guangming District, Shenzhen, Guangdong 518107
Department of Endoscopic Surgery, the Sixth Affiliated Hospital, Sun Yat-sen University, No.26 Yuancun Road II, Tianhe District, Guangzhou, Guangdong 510655
Source of Support: None, Conflict of Interest: None
Background: Inadequate bowel preparation leads to lower polyp detection rates, longer procedure times and lower cecal intubation rates. However, there is no consensus about high-quality bowel preparation, so our study evaluated graphical education and appropriate time before elective colonoscopy.
Patients and Methods: We performed a secondary analysis of a national colorectal cancer screening programme of 738 patients. The patients were divided into a group given a graphical information manual (n = 242) or a word-only one (n = 496). They were also divided into groups according to the interval between bowel preparation and colonoscopy: 6–8 h (Group 1, n = 106), 9–12 h (Group 2, n = 228) and 13–17 h (Group 3, n = 402). All patients were scored according to the Boston Bowel Preparation Scale (BBPS) during the examination.
Results: The bowel preparation of the graphical group was significantly better than the text group (P < 0.001). After adjustment, the bowel preparation score of Group 1 and Group 2 were both significantly higher than that of Group 3 (P = 0.012 and P = 0.032). Maximum BBPS was 6.31 when the interval time was 6.52 h (95% confidence interval: 5.95–6.66), and when the interval was <10 h, the BBPS was ≥6.
Conclusion: High-quality bowel preparation was linked to graphical education and appropriate time before colonoscopy. We suggest that the interval between taking the first laxative and colonoscopy should be <10 h, preferably 6.5 h. Prospective multicentre research is needed to give more evidence of high-quality bowel preparation methods.
Keywords: Bowel preparation, colonoscopy, educational methods, graphic guidance, interval time
|How to cite this URL:|
Sun J, Chen Y, Gu Y, Chen J, Li C, Zhou Q, Hu J, Jiang G. Graphical education and appropriate time before elective colonoscopy make better bowel preparation. J Min Access Surg [Epub ahead of print] [cited 2022 Jul 3]. Available from: https://www.journalofmas.com/preprintarticle.asp?id=346835
| ¤ Introduction|| |
In recent years, the prevalence of colorectal cancer (CRC), which has the second-highest rate of cancer-related mortality, has shown a significant upward trend. Colonoscopy is the first choice for CRC screening, for which adequate intestinal preparation is essential for proper visualisation of the colonic mucosa and optimal lesion detection. However, up to ¼ of colonoscopies are performed under inadequate bowel preparation, which may lead to lower detection rates of polyps and adenomas, higher associated costs, longer operation time, lower caecal intubation rates and increased likelihood of repeated operations. Adenoma detection rate (ADR) refers to the rate of finding at least one adenoma and is regarded as a major indicator of the quality of colonoscopy. Studies have shown that increased ADR is correlated with reduced morbidity and mortality of CRC. Therefore, bowel preparation is vital to ensure the quality of colonoscopy, which can not only improve ADR but also reduce the incidence of CRC. Previous studies have found that age, sex, physical activity, daily bowel movements, being examined in the afternoon, the time between finishing bowel preparation and examination, split dose and different education methods were associated with bowel preparation quality., Although education and timing of bowel preparation were influential, there is no clear consensus on the relative importance of these factors. A national CRC screening programme in China, initiated in 2018, provided data for secondary analysis to explore the factors which could improve bowel preparation quality before colonoscopy. The aims of this article were to find the factors affecting intestinal preparation, to strengthen intestinal cleaning, increase ADR and reduce the occurrence of colon cancer.
| ¤ Patients and Methods|| |
As shown in [Figure 1], our study was based on a secondary analysis of data from Project 1 and Project 2 of the national CRC screening programme based in the Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China. The screening programme was conducted in accordance with the ethical standards of the World Medical Association Declaration of Helsinki and the Ethical Guidelines for Clinical Research. The current study was approved by the Institutional Review Board of the Sixth Affiliated Hospital, Sun Yat-Sen University.
Inclusion and exclusion criteria
Project 1 included candidates 45–80 years old who met any of the following three items: (1) first-degree relatives of patients with CRC, (2) patients with other malignant tumours who have been cured or stable or (3) patients with previous intestinal polyps; or 2 of the following six items: (1) chronic diarrhea, (2) chronic constipation, (3) mucinous stool or bloody stool (excluding haemorrhoids and bleeding), (4) chronic appendicitis or appendectomy, (5) chronic cholecystitis or cholecystectomy or (6) major trauma events in the past 10 years. The exclusion criteria of Project 1 were: (1) a history of colonoscopy in the past 10 years, (2) a history of CRC, (3) a history of inflammatory bowel disease, (4) a history of hereditary CRC syndrome (including polyposis), (5) a history of colorectal surgery or radiotherapy, (6) definite active lower gastrointestinal bleeding or (7) pregnancy. Project 2 included patients 45–80 years old undergoing voluntary colonoscopy. The exclusion criteria of Project 2 were: (1) a history of colonoscopy in the past year, (2) a history of CRC, (3) a history of inflammatory bowel disease, (4) a history of hereditary CRC syndrome (including polyposis), (5) a history of colorectal surgery or radiotherapy, (6) definite active lower gastrointestinal bleeding or (7) pregnancy.
The following clinical-pathological data were collected for each patient: sex, age, occupation, education, body weight, height, body mass index, smoking status, alcohol intake, co-morbidities, history of abdominal surgery, polyp history and family tumour history. The following details of bowel preparation were also collected: education for bowel preparation before colonoscopy, types of laxatives and timing of laxative intake. The beginning time and detailed colonoscopy examination data were collected.
Methods of bowel preparation
All participants received standard education for bowel preparation, including face-to-face education by endoscopists who provided oral and written guidance with detailed instructions. Two different booklets were provided: In Project 1, these only contained words printed in black and white. The booklet of Project 2 carried color pictures to facilitate understanding of the instructions. However, they were both written in the same plain language and had the same content about bowel preparation, except for the timing of the start of bowel preparation. Patients who were provided with the graphical version of the educational guidance were called the graphic group (n = 242), and those who were given the text version were called the word group (n = 496).
Time of oral laxative administration
The laxatives were magnesium sulphate and polyethylene glycol (PEG). The protocol for the magnesium sulphate group was: Those examined in the morning took 50% magnesium sulphate (50 g magnesium sulphate dissolved in 100 ml water) at 5:00 in the morning, took 2000 ml water half an hour later to be drunk within 30 min; and those examined in the afternoon began to take laxatives at 10:00 on the same day, and the rest of the protocol were the same. The PEG protocol was: Project 1: First, 2 boxes of PEG were added to 2000 ml of water. Those examined in the morning began drinking about 500 ml of laxative at 19:00 the night before, the rest slowly drank a small amount over 2 h and walked around. After drinking laxatives, they drank 1000–2000 ml warm water. Those examined in the afternoon began drinking laxatives at 6:00 a. m. and the rest of the protocol were the same. In Project 2, the morning group started taking PEG at 22:00 the day before, and the afternoon group started taking it at 8:00 that day. The rest of the protocol were the same. For the convenience and the reasons of the original screening protocol, divided oral administration was not used.
Evaluation of bowel preparation
The colonoscopies were performed by experienced endoscopists, who had performed more than 1000 colonoscopies before the trials and were blinded to the grouping of the patients. Each patient was evaluated during colonoscopy insertion using the Boston Bowel Preparation Scale (BBPS). A total BBPS score of ≥6 with each segment score ≥2 is recognised as the standard of adequate bowel preparation. BBPS score divides the whole colon into three segments, which are the right colon (cecum and ascending colon), transverse colon (including hepatic flexure and splenic flexure) and left colon (descending colon, sigmoid colon and rectum).
All data were expressed as percentages, means and standard deviations; or medians and interquartile ranges as appropriate. Comparisons of baseline and clinical characteristics between two categories of BBPS were conducted by Pearson χ2 test for categorical variables and Student's t-test or the Wilcoxon test for continuous variables. A 4-knot restricted cubic spline regression model was used to plot the relationship between BBPS as a continuous variable and interval time, and a P value for nonlinearity was calculated. Linear regression was employed to assess the associations between baseline variables and BBPS. All statistical tests were 2-sided, and a P < 0.05 was considered significant. Analyses were performed using R (version 3.6.1; http://www.R-project.org).
| ¤ Results|| |
Baseline of the two projects
Our study consists of two parts. Project 1 included a text education manual, while Project 2 provided a graphic version. [Table 1] shows the basic information of the patients of both projects. However, due to early funding, some patients in the early stage of Project 1 received magnesium sulphate (n = 267) laxatives, with the remaining patients given PEG (n = 229), while the laxatives of Project 2 were all PEG. In addition, the starting time of taking laxatives in Project 2 differed from Project 1, so the interval between taking laxatives and examination was divided into three groups: 6–8 h (Group 1, n = 106), 9–12 h (Group 2, n = 228) and 13–17 h (Group 3, n = 402). In total, 738 patients were enrolled in this study, including 327 males and 411 females. There are 451 patients who only received secondary or below secondary education, including 101 who had only primary education. The basic information of the patients is shown in [Table 1].
Factors influencing bowel preparation quality
Of all the patients, 427 had a BBPS ≥6 and 311 had a BBPS <6. They were divided into adequate bowel preparation group and poor bowel preparation group. The BBPS was 5.5 ± 0.8 in the poor bowel preparation group and 7.5 ± 0.6 in the adequate bowel preparation group (P < 0.001). As shown in [Table 2], the two groups of patients with adequate bowel preparation were compared with those with insufficient bowel preparation, including sex, height, occupation type, education level, whether they had the previous disease or family history of CRC, education methods of bowel preparation, interval between administration of laxatives and the start of the examination, examination time (AM or PM), BBPS, polyps and adenomas. Family history of cancer (P < 0.001), laxative type (P < 0.001), ways of preaching (P < 0.001), examination time period (P = 0.002), BBPS (P < 0.001) and polyp detection rate (P = 0.003) were significant differences between the adequate bowel preparation group and poor bowel preparation group. In addition, the detection rate of polyps was 32.8% in the poorly prepared group, which was significantly lower than the 46.4% in the well-prepared group (P < 0.001). ADR was 15.6% in patients with inadequate bowel preparation and 24.8% in those with adequate preparation, a significant difference (P = 0.003).
|Table 2: Characteristics of two groups with inadequate and adequate bowel preparation|
Click here to view
As shown in [Table 3], correlation analysis of univariate linear regression was carried out based on the cleanliness of the whole colon and the right colon of the patients. It was found that males, systolic blood pressure (SBP), heart rate, family history of colon cancer and tumour, type of laxative, mode of education, interval from laxative administration to the beginning of the examination, examination period (PM) were related to bowel preparation of the whole colon. The same factors as with the whole colon except occupation were related to bowel preparation of the right colon. Comparing the P values of different influencing factors, we found that male, SBP (P = 0.003), heart rate (P = 0.001), family history of CRC (P < 0.001), family history of cancer (P < 0.001), type of laxative (P < 0.001), education methods (P < 0.001), interval between laxative administration and examination (P < 0.001) had more influence on the preparation of the whole colon, while these indicators had more influence on the preparation of the right colon.
|Table 3: Influencing factors of intestinal preparation for total colonic cleanliness and right colonic cleanliness (Correlation Analysis of Univariate Linear Regression)|
Click here to view
Different interval times between taking laxatives and examination
The BBPS scores of the three groups were 7.1 ± 1.2, 7.0 ± 1.0 and 6.4 ± 1.3, respectively. There were significant differences in BBPS scores between Group 2 and Group 3 (P < 0.001), and also between Group 1 and Group 3 (P < 0.001). As shown in [Figure 2]a, the maximum BBPS score was 7.11 (95% confidence interval [CI]: 6.96–7.27) when the interval was 6.87 h. After adjustment for gender, age, smoking history, drinking history, family history of CRC and cancer, type of laxatives and education methods, maximum BBPS was 6.31 [95% CI: 5.95–6.66] when the interval was 6.52 h. As shown in [Figure 2]b, When the interval is within 10 h, BBPS score was ≥6. The disadvantage is that the non-linear P value of the model is not significant after adjusting for those variables, but the non-linear trend is stable.
|Figure 2: (a) The relationship between Boston Bowel Preparation Scale and interval time of non-adjustment; (b) The relationship between Boston Bowel Preparation Scale and interval time after adjustment for gender, age, smoking history, drinking history, family history of colorectal cancer, family history of cancer, type of laxatives, education methods|
Click here to view
| ¤ Discussion|| |
Bowel preparation is a key part of successful colonoscopy. Few medical explorations require so rigorous and complex a preparation as bowel cleansing, so it may be considered a major barrier for some patients undergoing colonoscopy. Patients with graphical education before colonoscopy had better bowel preparation. The quality of bowel preparation was up to standard when taking the laxatives 10 h before colonoscopy, and the best time to complete bowel preparation was 6.5 h before colonoscopy. Patients' lack of information about colonoscopy and bowel preparation procedures can lead to anxiety. Adequate bowel preparation, reduced anxiety and successful colonoscopy results are all related to good patient education. International guidelines recommend the use of enhanced bowel preparation instructions to achieve better bowel preparation quality, but there is no consensus on which educational tool is best or how to implement it. In recent years, a variety of strategies to improve patient education have been studied, such as visual assistance, face-to-face conversation, telephone and SMS communication, as well as smartphones and social media applications; these have shown that the quality of intestinal cleansing has improved.,,,, However, the majority of patients receiving colonoscopy are the elderly, and most of them have limited education. They are not familiar with modern technology products such as visual aids, videos or social software, and cannot always master the functions of smartphones. Therefore, high-tech means to strengthen bowel preparation education may not be positively received by all patients and may indeed aggravate their anxiety.
Some studies have investigated health education on intestinal preparation using videos in hospitals. However, patients may not watch these again at home, leading to the possibility of missing important guidance information such as medication time and diet. Other studies investigated telephone communication to strengthen education, but drawbacks included lack of contact, poor communication and not being able to obtain this knowledge at a convenient time and place, which lead to insufficient quality of bowel preparation. Moreover, telephone and SMS may increase their anxiety about examination and bowel preparation.,,,, Inevitably, the quality of bowel preparation will be affected if patients forget the key components. Applications such as telephone follow-up or Wechat are time-intensive for staff. Any staff shortage may increase the workload of medical staff, which is difficult to promote and implement in hospitals with a shortage of human resources. Studies have shown that a graphic version of the education manual can improve bowel preparation and patient awareness, can be used anytime and anywhere and is easily accessible., It does not require internet access or social media, so all patients can obtain and check information on bowel preparation at any time during the process. Patients uncontactable by phone or lacking understanding of the Internet can have inadequate bowel preparation. When receiving the manual, patients are given face-to-face education on the key instructions, are offered the chance to ask questions to clarify any points they did not understand and can take notes in the manual. All of this helps to reduce the chance that they will forget the key components of bowel preparation once they return home. In our experiment, 59.3% and 70.8% of the patients received secondary or below secondary education in Project 1 and 2, respectively, including 101 who received only primary education. Our educational pamphlet can solve possible deficiencies in patients' knowledge and understanding with simple language and graphic annotation. Our research shows that, compared with the text-only version of the manual, the graphic version made it easier for patients to obtain information about bowel preparation and improve their understanding of how to carry this out. According to the judgement of blinded endoscopists, the graphic version of the education manual directly led to a significant improvement in the quality of bowel preparation. Up to ¼ of colonoscopies are associated with inadequate bowel preparation, which is partly due to the failure to reach a consensus on the interval between taking laxatives and examination. In our experiment, the interval of bowel preparation was defined as the time between when the patient started taking laxatives and when they began to receive bowel preparation. We defined this time as it differed between each person, possibly to a large extent. Another reason was that insufficient interval time could result in the residual gastric contents being aspirated into the lung, especially in the case of anaesthesia, which will lead to adverse conditions., Studies have shown that most anaesthesiologists thought it was safer to perform anesthesia colonoscopy 2–4 h after taking an intestinal preparation, and it also suggested waiting at least 4–8 h after colon preparation before sedation.,, Studies have shown different aspects on the time between laxative administration and colonoscopy. Gaspar et al. reported that a higher quality of bowel preparation could be obtained 8 h before the start of the examination and Church reported that the quality of bowel preparation 5 h after the start of bowel preparation was significantly better than that of patients 19 h or even longer after the start of bowel preparation. Eun et al. reported that patients with an interval of ≤4 h between the end of laxative intake and the beginning of colonoscopy had better bowel preparation quality than patients with an interval of >4 h in the full dose PEG method. Some studies found no difference in the preparation quality of colonoscopy within 7 h after completion of intestinal preparation, regardless of whether it was divided or one-time bowel preparation. Similar to the daily application scenario, this study focused on the interval between the time to start taking the laxative and the time to start the examination rather than other kinds of interval. Our study showed that there was no significant difference in the quality of bowel preparation between 6–8 h and 9–12 h, but the quality between 6–12 h was higher than that between 13–17 h, and the quality between 6–12 h was better than that between 13–17 h.
As shown in [Figure 2]b, only the relationship between the interval of bowel preparation and the quality of bowel preparation was presented as a linear chart after adjusting for the confounding factors of gender, age, smoking history, drinking history, family history of CRC or tumour, type of laxative and mode of education. Therefore, we concluded that the best interval time of bowel preparation was 6.5 h. When the interval was <10 h, bowel preparation was sufficient (BBPS ≥6). We, therefore, recommend that the interval between taking the last laxative dose and colonoscopy should be <10 h, preferably 6.5 h. Compared with previous studies, the time interval of optimal intestinal cleaning in this study is longer, which may be due to the different use of the split-dose method and the period of colonoscopy received by patients. In the experiment of Church, patients only underwent colonoscopy in the morning, while in this study patients were divided into two periods: morning and afternoon. In the study of Eun et al., patients received bowel preparation and colonoscopy on the same day. In our study, patients who underwent colonoscopy in the morning underwent bowel preparation the night before, so the interval was longer. There are some limitations in this study: (1) it was based at a single center and therefore a multicentre study should be conducted, (2) it was a secondary analysis and a retrospective study, not a prospective study, (3) it includes two projects which had variable inclusion for the patients and two kinds of laxatives were used for bowel preparation.
| ¤ Conclusion|| |
Patients who received graphical education before colonoscopy had better bowel preparation. As for the timing of bowel preparation, we suggest that the interval between taking the last laxative and colonoscopy should be <10 h, preferably 6.5 h.
Financial support and sponsorship
This study was funded by grants from the National Key R and D Programme of China (Grant No. 2017YFC1308800), the Sixth Affiliated Hospital of Sun Yat-Sen University Clinical Research 1010 Programme (Grant No. 1010PY(2020]-63) and the Sixth Affiliated Hospital of Sun Yat-Sen University of Horizontal Programme (Grant No. H202101162024041054).
Conflicts of interest
There are no conflicts of interest.
| ¤ References|| |
Arnold M, Sierra MS, Laversanne M, Soerjomataram I, Jemal A, Bray F. Global patterns and trends in colorectal cancer incidence and mortality. Gut 2017;66:683-91.
Gaspar R, Andrade P, Ramalho R, Antunes J, Macedo G. Bowel preparation: Modifiable factors to improve bowel cleansing. Eur J Gastroenterol Hepatol 2019;31:140.
Rex DK, Schoenfeld PS, Cohen J, Pike IM, Adler DG, Fennerty MB, et al.
Quality indicators for colonoscopy. Gastrointest Endosc 2015;81:31-53.
Kaminski MF, Wieszczy P, Rupinski M, Wojciechowska U, Didkowska J, Kraszewska E, et al.
Increased rate of adenoma detection associates with reduced risk of colorectal cancer and death. Gastroenterology 2017;153:98-105.
Hwang YJ, Shin DW, Kim N, Yoon H, Shin CM, Park YS, et al.
Sex difference in bowel preparation quality and colonoscopy time. Korean J Intern Med 2021;36:322-31.
Millien VO, Mansour NM. Bowel preparation for colonoscopy in 2020: A look at the past, present, and future. Curr Gastroenterol Rep 2020;22:28.
Alvarez-Gonzalez MA, Pantaleón Sánchez MÁ, Bernad Cabredo B, García-Rodríguez A, Frago Larramona S, Nogales O, et al.
Educational nurse-led telephone intervention shortly before colonoscopy as a salvage strategy after previous bowel preparation failure: A multicenter randomized trial. Endoscopy 2020;52:1026-35.
Özkan ZK, Fındık ÜY. Determination of the effectiveness of informing with the guidance of an education booklet in patients undergoing colonoscopy – A randomized controlled trial. J Perianesth Nurs 2020;35:502-7.
Hassan C, East J, Radaelli F, Spada C, Benamouzig R, Bisschops R, et al.
Bowel preparation for colonoscopy: European Society of Gastrointestinal Endoscopy (ESGE) Guideline – Update 2019. Endoscopy 2019;51:775-94.
Liu X, Luo H, Zhang L, Leung FW, Liu Z, Wang X, et al.
Telephone-based re-education on the day before colonoscopy improves the quality of bowel preparation and the polyp detection rate: A prospective, colonoscopist-blinded, randomised, controlled study. Gut 2014;63:125-30.
Lee YJ, Kim ES, Choi JH, Lee KI, Park KS, Cho KB, et al.
Impact of reinforced education by telephone and short message service on the quality of bowel preparation: A randomized controlled study. Endoscopy 2015;47:1018-27.
Guo X, Yang Z, Zhao L, Leung F, Luo H, Kang X, et al.
Enhanced instructions improve the quality of bowel preparation for colonoscopy: A meta-analysis of randomized controlled trials. Gastrointest Endosc 2017;85:90-7.e6.
Pillai A, Menon R, Oustecky D, Ahmad A. Educational colonoscopy video enhances bowel preparation quality and comprehension in an inner city population. J Clin Gastroenterol 2018;52:515-8.
Zapka JG, Lemon SC, Puleo E, Estabrook B, Luckmann R, Erban S. Patient education for colon cancer screening: A randomized trial of a video mailed before a physical examination. Ann Intern Med 2004;141:683-92.
Agrawal D, Marull J, Tian C, Rockey DC. Contrasting perspectives of anesthesiologists and gastroenterologists on the optimal time interval between bowel preparation and endoscopic sedation. Gastroenterol Res Pract 2015;2015:497176.
Tandon K, Khalil C, Castro F, Schneider A, Mohameden M, Hakim S, et al.
Safety of large-volume, same-day oral bowel preparations during deep sedation: A prospective observational study. Anesth Analg 2017;125:469-76.
Cheng CL, Liu NJ, Tang JH, Kuo YL, Lin CH, Tsui YN, et al.
Residual gastric volume after bowel preparation with polyethylene glycol for elective colonoscopy: A prospective observational study. J Clin Gastroenterol 2017;51:331-8.
Church JM. Effectiveness of polyethylene glycol antegrade gut lavage bowel preparation for colonoscopy-timing is the key! Dis Colon Rectum 1998;41:1223-5.
Eun CS, Han DS, Hyun YS, Bae JH, Park HS, Kim TY, et al.
The timing of bowel preparation is more important than the timing of colonoscopy in determining the quality of bowel cleansing. Dig Dis Sci 2011;56:539-44.
Castro FJ, Al-Khairi B, Singh H, Mohameden M, Tandon K, Lopez R. Randomized controlled trial: Split-dose and same-day large volume bowel preparation for afternoon colonoscopy have similar quality of preparation. J Clin Gastroenterol 2019;53:724-30.
[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3]