Orange juice intake reduces patient discomfort and is effective for bowel cleansing with polyethylene glycol during bowel preparation

Risk factors for inadequate bowel preparation before colonoscopy: A meta-analysis

OBJECTIVE

This meta-analysis aimed to comprehensively explore the risk factors for inadequate bowel preparation (IBP).

METHODS

We searched the Embase, PubMed, Web of Science, and The Cochrane Library databases up to August 24, 2023, to identify observational studies and randomized controlled trials (RCTs) that examined risk factors for IBP. A random effects model was used to pool the adjusted odds ratios and 95% confidence intervals.

RESULTS

A total of 125 studies (91 observational studies, 34 RCTs) were included. Meta-analyses of observational studies revealed that three preparation-related factors, namely, characteristics of last stool (solid or brown liquid), incomplete preparation intake, and incorrect diet restriction, were strong predictors of IBP. The other factors were moderately correlated with IBP incidence, including demographic variables (age, body mass index, male sex, Medicaid insurance, and current smoking), comorbidities (diabetes, liver cirrhosis, psychiatric disease, Parkinson's disease, previous IBP, poor mobility, inpatient, and Bristol stool form 1/2), medications (tricyclic antidepressants, opioids, antidepressants, narcotics, antipsychotics, and calcium channel blockers), and preparation-related factors (preparation-to-colonoscopy interval not within 3 to 5/6 h, nonsplit preparation, and preparation instructions not followed). No colonoscopy indications were found to be related to IBP. Meta-analyses of RCTs showed that education, constipation, stroke/dementia, and discomfort during preparation were also moderately associated with IBP. Most of the other findings were consistent with the pooled results of observational studies. However, primarily due to imprecision and inconsistency, the certainty of evidence for most factors was very low to moderate.

CONCLUSIONS

We summarized five categories of risk factors for IBP. Compared to demographic variables, comorbidities, medications, and colonoscopy indications, preparation-related elements were more strongly associated with IBP. These findings may help clinicians identify high-risk individuals and provide guidance for IBP prevention.

Dried lemon slices improve bowel cleansing quality of polyethylene glycol for colonoscopy preparation: randomized controlled trial

BACKGROUND

adequate bowel preparation is related to the quality of colonoscopy. Dried lemon slices can increase gastrointestinal peristalsis, which has shown potential as an adjuvant of bowel preparation. We hypothesized that the combination of dried lemon slices and polyethylene glycol (PEG) could improve the efficacy of bowel preparation and be more acceptable to participants.

AIM

to investigate the effectiveness of lemon slices combined with PEG for colonoscopy preparation.

METHODS

a prospective, single-center, randomized, controlled trial was performed of 521 patients randomly assigned to two groups. A total of 254 patients were given lemon slices based on conventional 4-L PEG treatment for the bowel, while 267 patients received only 4-L PEG treatment. Patients' basic information, procedure-related parameters, adverse effects, and subjective feelings were collected by questionnaires. Intestinal tract cleanliness was scored according to the Boston Bowel Preparation Scale (BBPS) by experienced endoscopists. Data were analyzed by the two-sample t-test or the Chi-squared test.

RESULTS

the BBPS scores were significantly higher in the PEG + lemon slice group (p < 0.05). The taste acceptability, satisfaction, and willingness to repeat bowel preparation were significantly higher in the PEG+ lemon slice group (p < 0.05). However, a larger proportion of patients from the PEG+ lemon slice group (30.7 %) suffered abdominal distension compared with the PEG group (20.6 %), while the incidence of other adverse effects was comparable between the two groups.

CONCLUSION

the addition of dried lemon slices to conventional PEG showed its superiority for bowel preparation.

Colon Bowel Preparation in the Era of Artificial Intelligence: Is There Potential for Enhancing Colon Bowel Cleansing?

BACKGROUND AND OBJECTIVES

Proper bowel preparation is of paramount importance for enhancing adenoma detection rates and reducing postcolonoscopic colorectal cancer risk. Despite recommendations from gastroenterology societies regarding the optimal rates of successful bowel preparation, these guidelines are frequently unmet. Various approaches have been employed to enhance the rates of successful bowel preparation, yet the quality of cleansing remains suboptimal. Intensive bowel preparation techniques, supplementary administration of bowel solutions, and educational interventions aimed at improving patient adherence to instructions have been commonly utilized, particularly among patients at a high risk of inadequate bowel preparation. Expedited strategies conducted on the same day as the procedure have also been endorsed by scientific organizations. More recently, the utilization of artificial intelligence (AI) has emerged for the preprocedural detection of inadequate bowel preparation, holding the potential to guide the preparation process immediately preceding colonoscopy. This manuscript comprehensively reviews the current strategies employed to optimize bowel cleansing, with a specific focus on patients with elevated risks for inadequate bowel preparation. Additionally, the prospective role of AI in this context is thoroughly examined.

CONCLUSIONS

While a majority of outpatients may achieve cleanliness with standard cleansing protocols, dealing with hard-to-prepare patients remains a challenge. Rescue strategies based on AI are promising, but such evidence remains limited. To ensure proper bowel cleansing, a combination of strategies should be performed.

2L polyethylene glycol combined with castor oil versus 4L polyethylene glycol for bowel preparation before colonoscopy among inpatients

Inpatients are more likely to have inadequate bowel preparation compared to outpatients. Although experts recommend 4L split polyethylene glycol (PEG) preparation, bowel preparation with castor oil (CaO) was recently found to reduce the volume of solution required. The aim of the study was to evaluate the cleansing effect and safety of 2L-PEG with Cao in bowel preparation among inpatients. Our study retrospectively analyzed the medical records and colonoscopy reports of inpatients (n = 1251) who underwent colonoscopy in the Affiliated Changzhou No.2 People Hospital of Nanjing Medical University, and the inpatients were divided into 2L-PEG-CaO and 4L-PEG group according to different bowel preparation protocols. Boston Bowel Preparation Scale (BBPS) is used to assess bowel preparation efficacy before colonoscopy. Furthermore, we also calculated other outcomes, such as polyp or adenoma detection rates and adverse events. A total of 1251 patients undergoing colonoscopy were included in this study, 738 were taken 4L-PEG and 513 2L-PEG-CaO. Both inpatients groups were matched for baseline characteristics. The 2L-PEG-CaO group was significantly higher than the 4L-PEG group on both BBPS (7.26 ± 1.75 vs 7.06 ± 1.58, P = .043) and adequate bowel cleansing rates (83.2% vs 77.4%, P = .011). Regarding adverse events, the 4L-PEG group was significantly higher than the 2L-PEG-CaO group on the incidence of abdominal fullness (6.4% vs 9.6%, P = .045) and adverse events (33.7% vs 28.5%, P = .048). The 2L split PEG with CaO preparation increased quality of bowel cleansing and improved tolerance in inpatients. Bowel preparation with 2L-PEG-CaO is suitable alternative to traditional 4L split PEG bowel preparation for colonoscopy of inpatients.

Safety and efficacy comparison of polyethylene glycol, hemp seed oil, and 5% sugar brine for bowel preparation in older patients: study protocol for a randomized controlled trial

BACKGROUND

The incidence of colorectal cancer among the middle-aged and elderly is gradually increasing in China. Colonoscopy is an effective method for the early diagnosis of colorectal cancer, and bowel preparation is one of many important factors affecting colonoscopy. Although there are many studies on intestinal cleansers, the results are not ideal. There is evidence that hemp seed oil has certain potential effects in intestinal cleansing, but prospective studies on this topic are still lacking.

METHODS

This is a randomized, double-blind, single-center clinical study. We randomly assigned 690 participants to groups each administered 3 L of polyethylene glycol (PEG), 30 mL of hemp seed oil and 2 L of PEG, or 30 mL of hempseed oil, 2 L of PEG, and 1000 mL of 5% sugar brine. The Boston Bowel Preparation Scale was considered the primary outcome measure. We evaluated the interval between consumption of bowel preparation and first bowel movement. Secondary indicators included the time of cecal intubation, detection rate of polyps and adenomas, willingness to repeat the same bowel preparation, whether the protocol was tolerated, and whether there were adverse reactions during bowel preparation and were evaluated after counting the total number of bowel movements.

DISCUSSION

This study aimed to test the hypothesis that hemp seed oil (30 mL) increases the quality of bowel preparation and reduces the amount of PEG. Previously, we found that its combination with 5% sugar brine can reduce the occurrence of adverse reactions.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2200057626. Prospectively registered on March 15, 2022.

The efficacy and tolerability of sports drink versus water in bowel preparations: a randomised controlled study

Background

An optimal bowel preparation can result in an improved colonoscopy. This study was to compare the effectiveness and safety of the use of a sports drink (Mizone) plus polyethylene glycol (PEG) solution with a water plus PEG solution in bowel preparations.

Methods

This was a randomised controlled study. All of the included patients were randomly divided into the following two groups: the PEG + Mizone group and the PEG + water group. The palatability of the solution was measured through the use of questionnaires. Additionally, bowel cleanliness was evaluated according to the Ottawa Bowel Preparation Scale (OBPS, 0–14, with higher values indicating worse cleanliness), as well as with the aid of colonoscopy videos.

Results

A total of 270 patients were enrolled. The rate of adequate bowel preparation was 74.8% in the PEG + Mizone group and 68.9% in the PEG + water group, with a risk difference of 5.9% (95% CI: − 4.8–16.6%), which indicated noninferiority (noninferiority margin: − 9.5% <  − 4.8%). However, patients rated the palatability (65.9% vs 44.4%, P < 0.001) and willingness to recommend or repeat (88.9% vs 75.6%, P = 0.004) the administration of the PEG + Mizone preparation as being better than those of the PEG + water preparation. The rates of adverse events during the bowel preparations were not significantly different between the two groups, except for bloating (PEG + Mizone vs PEG + water, 4.4% vs 13.3%, P = 0.010).

Conclusion

The concomitant use of PEG + Mizone was a well tolerated and effective bowel preparation, compared with the PEG + water treatment.

Trial registration

ClinicalTrials.gov NCT04247386. Registered on 30 Jan 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06658-2.

Comparison of the efficacy and safety between oral sulfate tablet and polyethylene glycol for bowel preparation before colonoscopy according to age

BACKGROUND

Recently, a novel oral sulfate tablet (OST) has been introduced for bowel preparation before colonoscopy. However, whether elderly patients can take OST is not yet clear, as OST consists of 28 tablets. We aimed to compare the efficacy and safety of OST and polyethylene glycol (PEG) for bowel preparation for colonoscopy according to age.

METHODS

We randomly divided subjects into an OST group and a PEG group and compared Boston Bowel Preparation Score (BBPS), bubble score, patient compliance and satisfaction, and safety between the 2 groups according to age (under 65 years of age vs 65 years of age and older).

RESULTS

Among the 179 participants, 61 were 65 years of age and older. The BBPS and bubble score of the OST group were better than that of the PEG group, regardless of age. The satisfaction of the OST group was better than that of the PEG group, regardless of age. The compliance was not different between the 2 groups; however, the OST group under 65 years of age had a higher rate of completing the dose within 2 hours compared with the PEG group under 65 years of age. Adverse events including abdominal distension, abdominal pain, nausea, or vomiting were not different between the 2 groups.

CONCLUSION

The use of OST for bowel preparation before colonoscopy is as effective and safe as PEG, and these results were consistent in elderly people 65 years of age and older.

Novel frontiers of agents for bowel cleansing for colonoscopy

The incidence of colorectal cancer (CRC) is characterized by rapid declines in the wake of widespread screening. Colonoscopy is the gold standard for CRC screening, but its accuracy is related to high quality of bowel preparation (BP). In this review, we aimed to summarized the current strategy to increase bowel cleansing before colonoscopy. Newly bowel cleansing agents were developed with the same efficacy of previous agent but requiring less amount of liquid to improve patients’ acceptability. The role of the diet before colonoscopy was also changed, as well the contribution of educational intervention and the use of adjunctive drugs to improve patients’ tolerance and/or quality of BP. The review also described BP in special situations, as lower gastrointestinal bleeding, elderly people, patients with chronic kidney disease, patients with inflammatory bowel disease, patients with congestive heart failure, inpatient, patient with previous bowel resection, pregnant/lactating patients. The review underlined the quality of BP should be described using a validate scale in colonoscopy report and it explored the available scales. Finally, the review explored the possible contribution of bowel cleansing in post-colonoscopy syndrome that can be related by a transient alteration of gut microbiota. Moreover, the study underlined several points needed to further investigations.

Antiemetics improve the tolerance of polyethylene glycol for colonoscopy preparation: A randomized clinical trial

BACKGROUND

Bowel preparation is essential to the success of colonoscopy. However, many patients cannot finish the preparation due to nausea and vomiting when taking polyethylene glycol (PEG). Dopamine-2 receptor antagonists, such as domperidone and sulpiride, are classical antiemetic drugs. This study aimed to explore the effect of domperidone and sulpiride on reducing the discomforts associated with PEG.

METHODS

Patients scheduled for colonoscopy were enrolled and randomly allocated into 3 groups. Patients in the domperidone group (Dom group) or sulpiride group (Sul group) took 2 doses of domperidone or sulpiride before PEG. Patients in the control group (Con group) followed the regular routine of PEG. Discomforts during bowel preparation and the quality of bowel preparation were assessed.

RESULTS

A total of 306 patients were enrolled. The participants in the Dom group and Sul group completed PEG better and had fewer abdominal discomforts than those in the Con group. The severity of nausea and abdominal fullness was lower in the Dom group and Sul group. The quality of bowel preparation was better in the Dom group and Sul group than Con group.

CONCLUSIONS

Domperidone and sulpiride could reduce the PEG-related discomfort and improve the quality of bowel preparation. This method may be a promising way to improve the satisfaction of bowel preparation for both patients and endoscopists.

Can adjuncts to bowel preparation for colonoscopy improve patient experience and result in superior bowel cleanliness? A systematic review and meta-analysis

BACKGROUND

Bowel preparation for colonoscopy is often poorly tolerated due to poor palatability and adverse effects. This can negatively impact on the patient experience and on the quality of bowel preparation. This systematic review and meta-analysis was carried out to assess whether adjuncts to bowel preparation affected palatability, tolerability and quality of bowel preparation (bowel cleanliness).

METHODS

A systematic search strategy was conducted on PubMed, MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews to identify studies evaluating adjunct use for colonoscopic bowel preparation. Studies comparing different regimens and volumes were excluded. Specific outcomes studied included palatability (taste), willingness to repeat bowel preparation, gastrointestinal adverse events and the quality of bowel preparation. Data across studies were pooled using a random-effects model and heterogeneity assessed using I2-statistics.

RESULTS

Of 467 studies screened, six were included for analysis (all single-blind randomised trials; n = 1187 patients). Adjuncts comprised citrus reticulata peel, orange juice, menthol candy drops, simethicone, Coke Zero and sugar-free chewing gum. Overall, adjunct use was associated with improved palatability (mean difference 0.62, 95% confidence interval 0.29-0.96, p < 0.001) on a scale of 0-5, acceptability of taste (odds ratio 2.75, 95% confidence interval: 1.52-4.95, p < 0.001) and willingness to repeat bowel preparation (odds ratio 2.92, 95% confidence interval: 1.97-4.35, p < 0.001). Patients in the adjunct group reported lower rates of bloating (odds ratio 0.48, 95% confidence interval: 0.29-0.77, p = 0.003) and vomiting (odds ratio 0.47, 95% confidence interval 0.27-0.81, p = 0.007), but no difference in nausea (p = 0.10) or abdominal pain (p = 0.62). Adjunct use resulted in superior bowel cleanliness (odds ratio 2.52, 95% confidence interval: 1.31-4.85, p = 0.006). Heterogeneity varied across outcomes, ranging from 0% (vomiting) to 81% (palatability), without evidence of publication bias. The overall quality of evidence was rated moderate.

CONCLUSION

In this meta-analysis, the use of adjuncts was associated with better palatability, less vomiting and bloating, willingness to repeat bowel preparation and superior quality of bowel preparation. The addition of adjuncts to bowel preparation may improve outcomes of colonoscopy and the overall patient experience.

Low-residual diet versus clear-liquid diet for bowel preparation before colonoscopy: meta-analysis and trial sequential analysis of randomized controlled trials

BACKGROUND AND AIMS

The aim of this study was to compare a low-residual diet (LRD) with a clear-liquid diet (CLD) for bowel preparation before colonoscopy.

METHODS

A systematic literature search was performed in PubMed, Ovid, and Cochrane databases for randomized clinical trials comparing LRD with CLD for bowel preparation before colonoscopy. The last search was performed on September 20, 2019. The primary outcome was adequate bowel preparation. The outcomes were compared using systematic review with meta-analysis and trial sequential analysis (TSA).

RESULTS

Twenty randomized controlled trials published between 2005 and 2019 with 4323 participants were included. LRD was comparable with CLD for adequate bowel preparation (P = .79; odds ratio [OR], 0.96; 95% confidence interval [CI], 0.72-1.29). The detection rates for polyps (P = .68; OR, 1.04; 95% CI, 0.86-1.27) or adenomas (P = .78; OR, 1.03; 95% CI, 0.86-1.23) were similar between the groups. There were significantly fewer advents in individuals in the LRD group: nausea (P = .02; OR, 0.72; 95% CI, 0.56-0.94), vomiting (P = .04; OR, 0.61; 95% CI, 0.38-0.98), hunger (P < .001; OR, 0.36; 95% CI, 0.24-0.53), and headache (P = .02; OR ,0.64; 95% CI, 0.44-0.93). In addition, significantly more individuals in the LRD group found it easy to complete the diet (P = .01; OR, 1.86; 95% CI, 1.15-3.00) and showed willingness to repeat it (P = .005; OR, 2.23; 95% CI, 1.28-3.89). TSA demonstrated that the cumulative Z curve crossed both the traditional boundary and the trial sequential monitoring boundary for adequate bowel preparation.

CONCLUSION

The present study demonstrated that LRD was comparable with CLD in the quality of bowel preparation before colonoscopy. More clinical trials are needed to confirm other outcomes.

A Randomized Trial of Split Dose 3 L Polyethylene Glycol Lavage Solution, 2 L Polyethylene Glycol Lavage Combined With Castor Oil, and 1 L of Polyethylene Glycol Lavage Solution Combined With Castor Oil and Ascorbic Acid for Preparation for Colonoscopy

Background: Castor oil (CaO) has the potential of halving the required volume of bowel preparation solution; however, no clinical trial investigated the efficacy of CaO on bowel preparation for colonoscopy in addition to polyethylene glycol (PEG).

Objectives: Our aim was to evaluate efficacy and safety of lower dose PEG together with 30 mL CaO alone or plus ascorbic acid (Asc) in bowel preparation before colonoscopy.

Methods: Two hundred and forty-six patients were allocated randomly to ingest 2 L PEG with 30 mL CaO, 1 L PEG with 30 mL CaO plus 5 g Asc, or 3 L PEG. We used Boston Bowel Preparation Scale (BBPS) to evaluate bowel preparation efficacy. We also determined other outcomes such as procedure time, polyp or adenoma detection rate, and adverse events (AEs).

Results: Of 282 patients recruited, 36 were excluded. Groups were matched for baseline characteristics except weight (P = 0.020) and body mass index (BMI) (P = 0.003). Patient's satisfaction was higher in 2 L PEG-CaO (P = 0.016) and 1 L PEG-CaO-Asc groups (P = 0·017). Patients' compliance was 67.5, 71.4, and 80.5% in 3 L PEG, 2 L PEG-CaO, and 1 L PEG-CaO-Asc groups (P = 0.014). Adequate bowel preparation rate was 75, 78.57, and 53.66% in 3 L PEG, 2 L PEG-CaO, and 1 L PEG-CaO-Asc groups (P = 0.021). There were no differences in terms of remaining outcomes.

Conclusions: Despite an increase in patients' satisfaction and compliance, 1 L PEG-CaO-Asc significantly decreased adequate bowel preparation rate. However, 2 L PEG-CaO improved the patients' satisfaction and compliance and increased adequate bowel preparation rate (Registration number, ChiCTR-IIR-17012418).

A head-to-head comparison of 4-L polyethylene glycol and low-volume solutions before colonoscopy: which is the best? A multicentre, randomized trial

PURPOSE

The purpose of this study is to compare the efficacy and tolerability of polyethylene glycol (PEG) to sodium picosulfate/magnesium citrate (SPMC) and low-volume polyethylene glycol/ascorbic acid (PEGA) in a single- or split-dose regimen for colonoscopy bowel preparation.

METHODS

This was a prospective, randomized, endoscopist-blinded, multicentre study. Outpatients received either PEG or SPMC or PEGA in a single or a split dose before the colonoscopy. Quality and tolerability of the preparation and complaints during preparation were recorded.

RESULTS

Nine hundred seventy-three patients were analysed. Satisfactory bowel cleansing (Aronchick score 1 + 2) was more frequent when a split dose was used irrespective of the solution type (PEG 90.1 vs 68.8%, PEGA 86.0 vs 71.6%, SPMC 84.3 vs 60.2%, p < 0.001). SPMC was the best tolerated followed by PEGA (p < 0.006) and PEG as the worst (p < 0.001). Tolerability did not correlate with the regimen and amount of the solution used. Female gender is associated with a higher incidence of nausea, vomiting and pain (p < 0.029).

CONCLUSIONS

Both PEG, PEGA and SPMC are fully comparable in terms of colonic cleansing when used in similar regimens. The split-dose preparation is more effective in all agents. SPMC and PEGA are better tolerated than PEG. The preparation regimen and/or the volume do not affect tolerability.

Subjective taste to polyethylene glycol is associated with efficacy of right colon preparation

AIM

A prospective observational trial with preparations using polyethylene glycol (PEG) to compare patient compliance and adverse events according to individual subjective taste.

METHODS

A total of 299 outpatients (mean ± standard deviation [SD] 56.5 ± 13.8 years, 172 males) were recruited for our study. We assessed the efficacy of bowel preparation, subjective taste to their regimens, compliance and adverse events during the preparation.

RESULTS

We achieved adequate preparation in 267 (89.3%). A total of 124 patients (41.5%) had 'unacceptable taste' to their regimens. The patients with acceptable taste had better compliance than the patients with unacceptable taste (p = .009). The patients with unacceptable taste had more frequent adverse events such as nausea, vomiting and abdominal bloating than the patients with acceptable taste (all p < .001, Table 2). Patients with unacceptable taste (16.1%) had more frequent inadequate preparation in overall colon than patients with acceptable taste (6.9%, p = .011). There was a significant difference in the efficacy of preparation of right colon between the two groups (p = .004).

CONCLUSION

Subjective taste to PEG is associated with efficacy of right colon preparation. In addition, subjective taste to PEG is associated with compliance and adverse events.

A Customized Mobile Application in Colonoscopy Preparation: A Randomized Controlled Trial

OBJECTIVES

Adherence with diet and prescribed purgative is essential for proper cleansing with low-volume bowel preparations. The aim of this work was to assess the effect of a customized mobile application (App) on adherence and quality of bowel preparation.

METHODS

One hundred and sixty (160) eligible patients scheduled for elective colonoscopy were randomly assigned to paper (control) or App-based instructions. The preparation consisted of low-fiber diet for 2 days, clear fluids for one day and split-dose sodium picosulfate/magnesium citrate (SPS). Before colonoscopy, information was collected regarding adherence with, and utility of the provided instructions. The colonoscopists, blinded to assignment, graded bowel preparation using the Aronchick, Ottawa, and Chicago preparation scales. The primary endpoint was adherence with instructions. Quality of preparation was a secondary endpoint.

RESULTS

No difference in overall adherence or bowel cleanliness was observed between the study arms. Adherence was reported in 82.4% of App vs. 73.4% of controls (P=0.40). An adequate bowel preparation on the Aronchick scale was noted in 77.2 vs. 82.5%, respectively (P=0.68). Mean scores on the Ottawa and Chicago scales were also similar. Gender, age, time of colonoscopy, and BMI did not influence preparation or adherence. Compliance with the clear fluid diet component was noted in 94% of patients with BMI<30 vs. 77% with BMI≥30 (P<0.01). SPS was well tolerated by 81.9% of patients. The App was user-friendly and received higher overall rating in this respect than paper instructions (P<0.01).

CONCLUSIONS

SPS is well tolerated and effective for bowel cleansing regardless of instruction method. Customized smartphone applications are effective, well-accepted and could replace standard paper instructions for bowel preparation.ClinicalTrials.gov: NCT02410720.

Sensory characterization of bowel cleansing solutions

AIM: To evaluate the sensory characteristics of commercial bowel cleansing preparations.

METHODS: Samples of 4 commercially available bowel cleansing preparations, namely polyethylene glycol electrolyte solution (PEG), PEG + ascorbic acid (PEG-Asc), sodium picosulfate (SPS), and oral sodium sulfate (OSS) were prepared according to the manufacturer’s instructions. Descriptive analysis was conducted (n = 14) using a 15-cm line scale with the Compusense at-hand^® sensory evaluation software. Acceptability testing (n = 80) was conducted using the 9-point hedonic scale. In addition, a Just-About-Right (JAR) scale was included for the four basic tastes to determine their intensity compatibility with acceptability levels in the products.

RESULTS: Samples were significantly different, in descriptive analysis, for all attributes (P < 0.05) except for sweetness. SPS received the highest ratings for turbidity, viscosity appearance, orange odor and orange flavor; PEG-Asc for citrus odor and citrus flavor; OSS for sweetener taste, sweet aftertaste, bitterness, astringency, mouthcoating, bitter aftertaste and throatburn, and along with PEG-Asc, the highest ratings for saltiness, sourness and adhesiveness. Acceptability results showed significant differences between the various samples (P < 0.05). SPS received significantly higher ratings for overall acceptability, acceptability of taste, odor and mouthfeel (P < 0.05). JAR ratings showed that PEG and PEG-Asc were perceived as slightly too salty; SPS and OSS were slightly too sweet, while SPS, PEG-Asc and OSS were slightly too sour and OSS slightly too bitter. While using small sample volumes was necessary to avoid unwanted purgative effects, acceptability ratings do not reflect the true effect of large volumes intake thus limiting the generalization of the results.

CONCLUSION: Further improvements are needed to enhance the sensory profile and to optimize the acceptability for better compliance with these bowel cleansing solutions.

A prospective randomized trial on the use of Coca-Cola Zero(®) vs water for polyethylene glycol bowel preparation before colonoscopy

AIM

The study aimed to determine whether Coca-Cola (Coke) Zero is a safe and effective solvent for polyethylene glycol (PEG).

METHOD

Between December 2013 and April 2014, 209 healthy adults (115 men, 95 women) scheduled for elective colonoscopy were randomized to use either Coke Zero (n = 100) or drinking water (n = 109) with PEG as bowel preparation. Each patient received two sachets of PEG to dissolve in 2 l of solvent, to be completed 6 h before colonoscopy. Serum electrolytes were measured before and after preparation. Bowel cleanliness and colonoscopy findings were recorded. Palatability of solution, adverse effects, time taken to complete and willingness to repeat the preparation were documented via questionnaire.

RESULTS

Mean palatability scores in the Coke Zero group were significantly better compared with the control group (2.31 ± 0.61 vs 2.51 ± 0.63, P = 0.019), with a higher proportion willing to use the same preparation again (55% vs 43%). The mean time taken to complete the PEG + Coke Zero solution was significantly faster (74 ± 29 min vs 86 ± 31 min, P = 0.0035). The quality of bowel cleansing was also significantly better in the Coke Zero group (P = 0.0297). There was no difference in the frequency of adverse events (P = 0.759) or the polyp detection rate (32% vs 31.2%). Consumption of either preparation did not significantly affect electrolyte levels or hydration status.

CONCLUSION

Coke Zero is a useful alternative solvent for PEG. It is well tolerated, more palatable, leads to quicker consumption of the bowel preparation and results in better quality cleansing.