Two liters of polyethylene glycol-electrolyte lavage solution versus sodium phosphate as bowel cleansing regimen for colonoscopy: a prospective randomized controlled trial

Polyethylene glycol versus split high-dose senna for bowel preparation: A comparative prospective randomized study

BACKGROUND AND AIM

The aim of this study was to compare the quality and tolerability of bowel preparation using split high-doses of sennosides versus split-dose polyethylene glycol (PEG).

METHODS

In this prospective, randomized, and endoscopist-blinded study, 474 outpatients were included and randomly assigned to two groups: Group 1 was comprised of 237 patients receiving split high-dose (1000 mg) sennoside solutions, and group 2 included 237 patients receiving 4 L of PEG. The efficacy of the preparations was evaluated on the Boston Bowel Preparation Scale (BBPS), and compliance and adverse effects were recorded.

RESULTS

The quality of colon cleansing and the ease of bowel preparation were significantly better in the senna group; the mean of total BBPS scores was 7.35 in the senna group and 6.57 in the PEG group, cleansing was adequate (BBPS score ≥ 6) in 89.9% of patients taking senna, and 73.8% in the PEG group (P = 0.001). The rates of vomiting in the senna and PEG groups were 12.7% and 29.5%, nausea rates were 28.7% and 43.9%, and abdominal pain rates were 70.9% and 43%, respectively (P < 0.001). Cecal intubation rates in the senna and PEG groups were 95.4% and 86.1% (P = 0.001), and the cecal intubation times were 6.73 ± 2.84 and 5.34 ± 5.98 min, respectively (P = 0.001).

CONCLUSIONS

Split high-dose senna is more effective than split-dose PEG in terms of bowel preparation quality and patient compliance. The patients who received senna had significantly less vomiting and nausea but significantly more abdominal pain. Thus, senna may be used as an alternative to PEG for bowel preparation.

Comparison of patterns of laxative ingestion to improve bowel preparation for colonoscopy: a pilot randomized clinical trial

Background and study aims  Negative experiences with bowel preparation are a barrier to uptake of colonoscopy. The aim of this study was to examine the impact of different flavoring of polyethylene glycol (PEG) laxatives on patient satisfaction with and adequacy of bowel preparation during colonoscopy. Patients and methods  This was a single-blind (endoscopist), parallel design, randomized trial (NCT02062112) during which patients scheduled for colonoscopy were assigned to one of three groups: Group 1 (no laxative flavoring, n = 84); Group 2 (flavored entire laxative, n = 90) and Group 3 (tasted PEG with and without flavoring and decided how they want to drink the rest of the laxatives (choice group), n = 82). Patients rated their bowel preparation experience (satisfaction) and endoscopists accessed adequacy of bowel preparation during colonoscopy. Results  There were no differences in patient ratings across the groups (1, 2 and 3) in taste of the laxatives ( P  = 0.67), ease of drinking ( P  = 0.53), and overall experience of bowel preparation process ( P  = 0.18). However, higher percentage of patients in the choice group would want the same laxative again if they were going to have a repeat colonoscopy in the future (72.5 % vs 81.3 % vs 88.9 %, P  = 0.04). Surprisingly, adequacy of bowel preparation was highest among patients who drank their PEG unflavored (89.3 % vs 80 % vs 75.5 %, P  = 0.07) and the had highest rates of adenoma detection (40.5 % vs 23.3 vs 39.0, P  = 0.03). Conclusions  There were no differences in overall tolerability of bowel preparation by patterns of flavoring of PEG. Those who drank unflavored PEG were less satisfied but had better clinical outcome, suggesting minimum justification effect in bowel preparation process.

Polyethylene glycol plus ascorbic acid for bowel preparation in chronic kidney disease

The safety of polyethylene glycol plus ascorbic acid has not been fully investigated in patients with renal insufficiency. High-dose ascorbic acid could induce hyperoxaluria, thereby causing tubule-interstitial nephritis and renal failure. This study aims to evaluate the safety and efficacy of polyethylene glycol plus ascorbic acid in patients with chronic kidney disease.We retrospectively reviewed prospectively collected data on colonoscopy in patients with impaired renal function. Patients were divided into 2 groups: 2 L polyethylene glycol plus ascorbic acid (n = 61) and 4 L polyethylene glycol (n = 80). The safety of the 2 groups was compared by assessing the differences in laboratory findings before and after bowel cleansing.The laboratory findings were not significantly different before and after the administration of 2 L polyethylene glycol plus ascorbic acid or 4 L polyethylene glycol. In both groups, the estimated glomerular filtration rate was not influenced by the administration of the bowel-cleansing agent. Patients' reports on tolerance and acceptability were better in the 2 L polyethylene glycol plus ascorbic acid group than in the 4 L polyethylene glycol group.The 2 L polyethylene glycol plus ascorbic acid solution is a safe choice for bowel preparation before colonoscopy in patients with impaired renal function.

Split-Dose Polyethylene Glycol Is Superior to Single Dose for Colonoscopy Preparation: Results of a Randomized Controlled Trial

Background. The efficacy of colonoscopy in detecting abnormalities within the colon is highly dependent on the adequacy of the bowel preparation. The objective of this study was to compare the efficacy, safety, and tolerability of PEG lavage and split-dose PEG lavage with specific emphasis on the cleanliness of the right colon. Methods. The study was a prospective, randomized, two-arm, controlled trial of 237 patients. Patients between the age of 50 and 75 years were referred to an outpatient university screening clinic for colonoscopy. Patients were allocated to receive either a single 4 L PEG lavage or a split-dose PEG lavage. Results. Overall, the bowel preparation was superior in the split-dose group compared with the single-dose group (mean Ottawa score 3.50 ± 2.89 versus 5.96 ± 3.53; P < 0.05) and resulted in less overall fluid in the colon. This effect was observed across all segments of the colon assessed. Conclusions. The current study supports use of a split-dose PEG lavage over a single large volume lavage for superior bowel cleanliness, which may improve polyp detection. This trial is registered with ClinicalTrials.gov identifier NCT01610856.

Comparison of the efficacy and safety of sodium phosphate tablets and polyethylene glycol solution for bowel cleansing in healthy Korean adults

PURPOSE

Bowel cleansing is generally regarded as time-consuming and unpleasant among patients. Patients commonly state that bowel preparation provokes more discomfort than the actual colonoscopic examination. The purpose of this study was to compare two regimens of sodium phosphate (NaP) tablets versus polyethylene glycol (PEG) solution for bowel preparation in healthy Korean adults.

MATERIALS AND METHODS

This was a single center, prospective, open-label, investigator-blinded, randomized, controlled-pilot study. A total of 62 healthy Korean subjects were randomly assigned to two groups (NaP vs. PEG). Efficacy, safety, and patient-related outcomes, as well as procedural parameters, were evaluated.

RESULTS

Although there were no significant differences in total Ottawa bowel quality score, fluid scores and the rate of adequate bowel preparation were significantly better in the NaP group than the PEG group. Additionally, the NaP group showed better results regarding patient tolerance, satisfaction, preference, and rate of adverse events than the PEG group. Significant fluctuations in specific serum electrolytes were common and of a greater magnitude in the NaP group than the PEG group. However, these abnormalities were transient and did not result in serious complications and side effects.

CONCLUSION

In this study, NaP tablets were shown to be an effective, well-tolerated, and acceptable regimen for bowel preparation. Also, our study suggests that NaP tablets may be safe and can be used as a bowel cleansing agent in healthy adults undergoing elective colonoscopy. Further multicenter, large scale studies are needed to confirm these findings.

Colonoscopy preparation-induced disorders in renal function and electrolytes

Colonoscopy and flexible sigmoidoscopy are commonly used mainly for colon cancer screening and detection, but also in several other situations such as inflammatory bowel disease (for diagnosis and follow up) and gastrointestinal hemorrhage. Bowel cleansing preparations mainly include polyethylene glycol and oral sodium phosphate solutions, with the later being most frequently used due to better toleration from patients. Despite their favourable safety profile these agents have been associated with renal function deterioration and electrolyte disorders, some of which were serious or even fatal. The present paper discusses the complications associated with colonoscopy preparation agents.

Effects of a 250-mL enema containing sodium phosphate on electrolyte concentrations in healthy volunteers: An open-label, randomized, controlled, two-period, crossover clinical trial

BACKGROUND

Enemas are used by individuals with constipation and are often required before certain medical diagnostic procedures and surgical interventions. However, abnormalities in serum electrolyte concentrations have been associated with enema use.

OBJECTIVE

The aim of this study was to determine the changes in serum electrolyte concentrations (phosphorus, calcium, sodium, and potassium) and urinary phosphorus elimination after the administration of a sodium phosphate enema.

METHODS

Healthy volunteers aged 35 to 70 years were eligible for this open-label, randomized, controlled, 2-period, crossover clinical trial at the Clinical Research Unit of the University Hospital of Navarra, Pamplona, Spain. The study comprised 2 one-day periods separated by a 7-day washout. All subjects were randomly assigned in a 1:1 ratio to 1 of 2 study sequences: (1) a single dose of Enema Casen® 250 mL in the first period followed by no treatment (control) in the second period, or (2) no treatment in the first period followed by a single dose of the study drug in the second period. The sequence of treatment was assigned using a randomization table that was prepared before the beginning of the study. Serum concentrations of phosphorus, sodium, potassium, and calcium were measured in both periods. Urinary phosphorus elimination was measured for 12 hours after enema administration (Ae0-12) in a subset of the subjects in the second period. Adverse events (AEs) were monitored by the investigators throughout the study. Normal ranges for the electrolytes were as follows: phosphorus, 2.5 to 5 mg/dL; calcium, 8.5 to 10.5 mg/dL; sodium, 135 to 145 mEq/L; and potassium, 3.5 to 5 mEq/L.

RESULTS

Twenty-four subjects (12 men, 12 women; mean [SD] age, 47.8 [9.6] years [range, 36-68 years]) participated in the study. All of the subjects were white and none were smokers. Twelve hours after enema administration, mean serum phosphorus and sodium concentrations increased by a mean of 1.18 mg/dL and 1.32 mEq/L, respectively (both, P < 0.001). Mean serum phosphorus concentrations were above the upper limit of normal (5 mg/dL) at 30 and 60 minutes after enema administration. In all subjects the values returned to normal within 4 hours after enema administration; a meal was provided after a 3-hour fast. Four subjects (16.7%) had ≥1 serum phosphorus concentration measurement ≥7 mg/dL, a value that is considered serious hyperphosphatemia. A statistically significant correlation was found between phosphorus Cmax and enema retention time (r (2) = 0.452; P < 0.001). No abnormal serum concentrations were obtained for the other electrolytes measured. Phosphorus Ae0-12 was increased after enema administration by 86% (P < 0.001). No serious AEs were observed, although 13 AEs were reported in 9 subjects. None of the changes in serum electrolyte concentrations were associated with clinical symptoms.

CONCLUSIONS

Administration of an enema containing 250 mL of sodium phosphate was associated with serum phosphorus concentrations of ≥7 mg/dL in 16.7% of the healthy subjects who participated in the study; however, none of those subjects experienced hypocalcemia. Enema retention time was significantly correlated with the degree of phosphatemia.

Comparison of the Efficacy and Tolerability between Same-day Picosulfate and Split-dose Polyethylene Glycol Bowel Preparation for Afternoon Colonoscopy: A Prospective, Randomized, Investigator-blinded Trial

Background/Aims

In the present study, we evaluated the efficacy and tolerability between same-day bowel preparation protocols using 2 sachets of Picosulfate and a 4 L split-dose polyethylene glycol (PEG) bowel preparation for afternoon colonoscopy.

Methods

The study had a single-center, prospective, randomized, and investigator-blinded, non-inferiority design. We evaluated bowel preparation quality according to the Ottawa scale, patient tolerability, compliance, incidence of adverse events, sleep quality, and polyp/adenoma detection rate.

Results

Among the 196 patients analyzed (mean age, 55.3 years; 50.3% men), 97 received the same-day regimen of 2 sachets of picosulfate (group A) and 99 received the 4 L split-dose PEG regimen (group B). The Ottawa score of the total colon was 4.05±1.56 in group A and 3.80±1.55 in group B (P=0.255). The proportion of patients having adequate bowel preparation in the same-day picosulfate group (61.5%) was slightly less than the 4 L PEG group (71.3%); however, the difference was not statistically significant (P=0.133). Tolerability of the group A regimen was superior to that of the group B regimen (P<0.000). The same-day picosulfate regimen was associated with fewer adverse events, such as abdominal bloating (P=0.037) and better sleep quality (P<0.000).

Conclusions

The same-day picosulfate regimen and the 4 L split-dose PEG regimen had similar efficacy in bowel preparation for afternoon colonoscopy. However, the same-day picosulfate regimen was easier to administer, produced fewer adverse events, and enabled better sleep quality.

Complications of colonoscopy

Colonoscopy is a relatively invasive modality for the diagnosis and treatment of colorectal disease and for the prevention or early detection of colorectal neoplasia. Millions of colonoscopies are performed each year in the United States by endoscopists with varying levels of skill in colons that present varying levels of challenge. Although better scope technology has made colonoscopy gentler and more accurate, the sheer number of examinations performed means that complications inevitably occur. This article considers the most common complications of colonoscopy, and advises how to minimize their incidence and how to treat them if they do occur.

Adding pineapple juice to a polyethylene glycol-based bowel cleansing regime improved the quality of colon cleaning

BACKGROUND/AIMS

An unsuccessful colonoscopy procedure is often related to inadequate bowel cleansing. It is difficult for patients to finish the whole 4 liters of polyethylene glycol-electrolyte lavage (PEG-EL) because of its salty taste and the large quantity. Pineapple juice has been shown to be an effective agent in the dissolution of undigested food in the stomach. This study assessed the effectiveness of both 2 and 4 liters of PEG-EL in precolonoscopic bowel cleansing and the quality of colonoscopic cleaning by adding 1 liter of pineapple juice to a reduced-volume PEG-based regime.

METHODS

The patients were chosen from those undergoing a colonoscopic procedure. A total of 126 patients were randomized into 3 groups receiving 3 different PEG-EL (Golytely®) regimes, i.e. 4 liters of PEG-EL (group 1, n = 44), 2 liters of PEG-EL (group 2, n = 39) or 2 liters of PEG-EL with 1 liter of pineapple juice (Dimes® 100%; group 3, n = 43).

RESULTS

Both the 4- and 2-liter PEG-EL regimes resulted in similar bowel cleansing scores in all parts of the colonic segments. However, adding 1 liter of pineapple juice to the reduced-volume PEG-EL regime improved the quality of the cleansing on the right side of the colon and in the transverse colon. Adequate bowel cleansing was achieved in 68.1% of the patients in group 1, 63.9% in group 2 and 80% in group 3 (the lowest score in one of the segments). On the other hand, the tolerability of the regimes was similar in all 3 groups (p = 0.509).

CONCLUSIONS

Reduced PEG-EL (2 rather than 4 liters) may be sufficient for precolonoscopic bowel cleansing in the Turkish population. Administration of pineapple juice in the reduced-dose preparation regime may improve the quality of the bowel cleaning.

A pilot study using reduced-volume oral sulfate solution as a preparation for colonoscopy among a Japanese population

BACKGROUND

This pilot study sought to investigate the performance and safety of a reduced-volume oral sulfate solution for use as a bowel-cleansing regimen prior to colonoscopy in a Japanese population.

METHODS

Subjects followed a prescribed split-dose regimen in which the first portion was taken on the evening before colonoscopy and the second portion on the morning of the procedure. To determine the performance of this regimen, the quality of colon cleansing was assessed in each case using a validated four-point scale, and elapsed time to complete the preparation was recorded. Side effects and adverse events were investigated by blood sampling and questionnaire.

RESULTS

The successful preparation rate based on the colon-cleansing score was 97 % (30/31). Mean elapsed time to complete the preparation on the day of colonoscopy was 71 min. Serum levels of indirect bilirubin were significantly increased to abnormal levels following the preparation, although these changes were only transient. Preparation-related symptoms of nausea and vomiting were presented in only one case.

CONCLUSIONS

This pilot study showed the oral sulfate solution-based bowel preparation to be safe, easy, and quick to use for Japanese patients. A larger study is necessary to statistically verify these results.

Colonoscopy preparation: polyethylene glycol with Gatorade is as safe and efficacious as four liters of polyethylene glycol with balanced electrolytes

BACKGROUND

Four liters of polyethylene glycol 3350 (PEG) with balanced electrolytes for colonoscopy preparation has had poor acceptance. Another approach is the use of electrolyte-free PEG combined with 1.9 L of Gatorade. Despite its widespread use, there are no data on metabolic safety and minimal data on efficacy. Our aim was to assess the efficacy and electrolyte safety of these two PEG-based preparations.

METHODS

This was a prospective, randomized, single-blind, non-inferiority trial. Patients were randomized to 238 g PEG + 1.9 L Gatorade or 4 L of PEG-ELS containing 236 g PEG. Split dosing was not performed. On procedure day blood was drawn for basic chemistries. The primary outcome was preparation quality from procedure photos using the Boston Bowel Preparation Scale.

RESULTS

We randomized 136 patients (66 PEG + Gatorade, 70 PEG-ELS). There were no differences in preparation scores between the two agents in the ITT analysis (7.2 ± 1.9 for PEG-ELS and 7.0 ± 2.1 for PEG + Gatorade; p = 0.45). BBPS scores were identical for those who completed the preparation and dietary instructions as directed (7.4 ± 1.7 for PEG-ELS, and 7.4 ± 1.8 for PEG + Gatorade; p = 0.98). There were no statistical differences in serum electrolytes between the two preparations. Patients who received PEG + Gatorade gave higher overall satisfaction scores for the preparation experience (p = 0.001), and had fewer adverse effects.

CONCLUSIONS

Use of 238 g PEG + 1.9 L Gatorade appears to be safe, better tolerated, and non-inferior to 4 L PEG-ELS. This preparation may be especially useful for patients who previously tolerated PEG-ELS poorly.

A randomized controlled trial of four precolonoscopy bowel cleansing regimens

BACKGROUND

The ideal bowel cleansing regimen for colonoscopy has yet to be determined.

OBJECTIVE

To compare the cleansing efficacy, and patient tolerability and safety of four bowel preparation regimens.

METHODS

A total of 834 patients undergoing outpatient colonoscopy were randomly assigned to one of four regimens: 4 L polyethylene glycol (PEG); 2 L PEG + 20 mg bisacodyl; 90 mL of sodium phosphate (NaP); or two sachets of a commercially available bowel cleansing solution (PSMC) + 300 mL of magnesium citrate (M). The primary outcome measure was cleansing efficacy, which was scored by blinded endoscopists using the Ottawa Bowel Preparation Scale. Secondary outcome measures were bowel preparation quality according to time of colonoscopy, and patient tolerability and safety.

RESULTS

The mean total cleansing score was significantly worse in the NaP group compared with the other three groups (P<0.0001). The mean cleansing scores were worse in patients who underwent morning versus afternoon colonoscopy, a finding that was consistent in all four groups. PSMC + M was the best tolerated regimen. No clinically significant mean changes in creatinine or electrolyte levels were identified, although a significantly higher proportion of patients in the NaP group developed hypokelemia (P<0.0001).

CONCLUSIONS

2 L PEG + 20 mg bisacodyl, or PSMC + M was as efficacious as 4 L PEG and superior to NaP for bowel cleansing. A short interval between the completion of bowel preparation and the start of colonoscopy (ie, 'runway time'), irrespective of bowel preparation regimen, appeared to be a more important predictor of bowel cleanliness than the cathartic agents used.

Different bowel preparation schedule leads to different diagnostic yield of proximal and nonpolypoid colorectal neoplasm at screening colonoscopy in average-risk population

BACKGROUND

Accumulating evidence indicates that the timing of bowel preparation is crucial, but its impact on the diagnostic yield of proximal or nonpolypoid colorectal neoplasm remains unclear.

OBJECTIVE

This study aimed to investigate the impact of the timing of bowel preparation on the adenoma detection rate for nonpolypoid colorectal neoplasm at colonoscopy.

DESIGN

This study is a retrospective analysis of a screening colonoscopy cohort database.

SETTING

The investigation was conducted at a screening colonoscopy unit in an university hospital.

PATIENTS

A consecutive series of 3079 subjects who received primary screening colonoscopy with different timing of bowel preparation was analyzed.

INTERVENTION

Different timing of bowel preparation (same day vs prior day) was studied.

MAIN OUTCOME MEASURES

The main outcomes measured were patient demographics, timing of bowel preparation, colon-cleansing levels, diagnostic yields of colonoscopy, including adenoma, advanced adenoma, and nonpolypoid colorectal neoplasm.

RESULTS

There were a total of 1552 subjects in the morning group and 1527 in the evening group. More subjects had proximal adenoma (175, 11.3% vs 138, 9.0%, P = .04), advanced adenoma (68, 4.4% vs 46, 13.0%, P = .044), nonpolypoid colorectal neoplasm (98, 6.3% vs 67, 4.4%, P = .018), proximal nonpolypoid colorectal neoplasm (71, 4.6% vs 40, 2.6%, P = .004), and advanced nonpolypoid colorectal neoplasm (25, 1.6% vs 12, 0.8%, P = .036) detected by same-day preparation. On multivariate regression analysis, the adenoma detection rate was significantly higher in the same-day group regarding overall and proximal adenoma (OR 1.23, 95% CI: 1.00-1.50; OR 1.35, 95% CI: 1.05-1.74), advanced adenoma (OR 1.53, 95% CI: 1.04-2.28), overall, proximal, and advanced nonpolypoid colorectal neoplasm (OR 1.48, 95% CI: 1.06-2.08; OR 1.82, 95% CI: 1.20-2.75; OR 1.96, 95% CI: 1.12-3.37). The adenoma detection rate was also significantly different among endoscopists.

LIMITATION

This was a single-center, nonrandomized trial.

CONCLUSIONS

Improving bowel preparation quality by same-day preparation may lead to enhanced detection of overall, proximal, and advanced nonpolypoid colorectal neoplasm.

Efficacy and tolerability of split-dose PEG compared with split-dose aqueous sodium phosphate for outpatient colonoscopy: a randomized, controlled trial

BACKGROUND AND AIMS

Adequate bowel cleansing is essential for a high-quality, effective, and safe colonoscopy. The aims of this study were to compare the efficacy and tolerability of split-dose polyethylene glycol with aqueous sodium phosphate for outpatients who underwent scheduled colonoscopy.

METHODS

In this prospective trial, 207 outpatients (aged between 18 and 65 years, with normal renal function, at low risk for renal damage) were randomized to receive split-dose preparation of PEG (2 L/2 L) (N = 103) or NaP (45 mL/45 mL, 12 h apart) (N = 104) without strict diet restriction the day before colonoscopy. The bowel cleansing efficacy of preparations was rated according to the Ottawa scale and the patient tolerability was assessed using a patient questionnaire.

RESULTS

There was no significant difference between the two groups for the mean total score using the Ottawa bowel preparation scale (P = 0.181). Significantly greater residual colonic fluid was observed in the split-dose PEG group (1.24 ± 0.49) than in the NaP group (1.04 ± 0.53) (P = 0.007). Patient compliance, preference, and acceptance of a two preparation regimen were similar with no significant differences (P = 0.095, P = 0.280 and P = 0.408, respectively). The overall incidence of adverse events was not significantly different between the two groups; however, the split-dose PEG group tended to have fewer adverse events (52/103 [50.5%], 66/104 [63.5%], P = 0.059) and had significantly less nausea and vomiting (P = 0.036).

CONCLUSIONS

Split-dose PEG, compared with split-dose NaP, is associated with more residual colonic fluid, but produces equivalent colon cleansing efficacy and results in less nausea and vomiting, which might improve patient tolerability (clinical trial registration number NCT01229800).

Severe hypocalcaemia and hyperphosphataemia caused by oral sodium phosphate fleet solution in a haemodialysis patient after parathyroidectomy

We report a case with severe electrolyte disturbance after the use of oral sodium phosphate solution (OSPS). A 69-year-old patient on haemodialysis received 45 mL of OSPS for bowel preparation. He had symptomatic hypocalcaemia with a serum calcium level of 0.95 mmol/L and serum phosphate level of 4.73 mmol/L. He was treated with haemodialysis and intravenous calcium supplementation. This patient had total parathyroidectomy recently leading to the absence of parathyroid hormone response. OSPS has been reported to cause life-threatening electrolyte disturbance especially in patients with renal failure. We suggest the use of safer alternatives for bowel preparations in renal failure patients.

Bowel Preparation for Colonoscopy with Sodium Phosphate Solution versus Polyethylene Glycol-Based Lavage: A Multicenter Trial

BACKGROUND

Adequate bowel preparation is essential for accurate colonoscopy. Both oral sodium phosphate (NaP) and polyethylene glycol-based lavage (PEG-ELS) are used predominantly as bowel cleansing modalities. NaP has gained popularity due to low drinking volume and lower costs. The purpose of this randomized multicenter observer blinded study was to compare three groups of cleansing (NaP, NaP + sennosides, PEG-ELS + sennosides) in reference to tolerability, acceptance, and cleanliness.

PATIENT AND METHODS

355 outpatients between 18 and 75 years were randomized into three groups (A, B, C) receiving NaP = A, NaP, and sennosides = B or PEG-ELS and sennosides = C. Gastroenterologists performing colonoscopies were blinded to the type of preparation. All patients documented tolerance and adverse events. Vital signs, premedication, completeness, discomfort, and complications were recorded. A quality score (0-4) of cleanliness was generated.

RESULTS

The three groups were similar with regard to age, sex, BMI, indication for colonoscopy, and comorbidity. Drinking volumes (L) (A = 4.33 + 1.2, B = 4.56 + 1.18, C = 4.93 + 1.71) were in favor of NaP (P = .005). Discomfort from ingested fluid was recorded in A = 39.8% (versus C: P = .015), B = 46.6% (versus C: P = .147), and C = 54.6%. Differences in tolerability and acceptance between the three groups were statistically not significant. No differences in adverse events and the cleanliness effects occurred in the three groups (P = .113). The cleanliness quality scores 0-2 were calculated in A: 77.7%, B: 86.7%, and C: 85.2%.

CONCLUSIONS

These data fail to demonstrate significant differences in tolerability, acceptance, and preparation quality between the three types of bowel preparation for colonoscopy. Cleansing with NaP was not superior to PEG-ELS.

Comparison of two sodium phosphate tablet-based regimens and a polyethylene glycol regimen for colon cleansing prior to colonoscopy: a randomized prospective pilot study

PURPOSE

The aim of this pilot study was to compare the performance and safety of the newly developed sodium phosphate (NaP) tablet (with and without laxatives) and polyethylene glycol (PEG), as bowel-cleansing regimens prior to colonoscopy.

METHODS

A total of 35 patients were randomized to one of the following three groups: NaP + laxative, NaP, or PEG. Quality of colon cleansing was assessed using a validated four-point scale, and the primary outcome measures were the mean overall colon cleansing and microcrystalline cellu1ose (MCC)-remaining scores in each group.

RESULTS

The mean elapsed time for bowel cleansing in the NaP + laxative group (167.72 +/- 21.37 min) was significantly less than in the NaP group (218.00 +/- 20.58 min) and the PEG group (202.00 +/- 27.91 min; n = 11, 10, and 10 respectively; P < 0.05). The NaP + laxative group showed a superior overall colon-cleansing score compared to both the NaP and PEG groups and similarly, the overall colon MCC-remaining score in the NaP + laxative group was superior to the NaP group. Serum levels of inorganic phosphorus were significantly increased to abnormal levels in the NaP + laxative and NaP groups, but these increases were only transient.

CONCLUSIONS

This pilot study shows that NaP-based bowel preparations are easy, quick, and safe to use. Colonoscopic visualization is decreased by MCC when NaP is used alone but is improved by the addition of laxatives on the previous day. A larger study is necessary to statistically verify these results.

CT colonography with limited bowel preparation: prospective assessment of patient experience and preference in comparison to optical colonoscopy with cathartic bowel preparation

The purpose of this study was to prospectively compare participant experience and preference of limited preparation computed tomography colonography (CTC) with full-preparation colonoscopy in a consecutive series of patients at increased risk of colorectal cancer. CTC preparation comprised 180 ml diatrizoate meglumine, 80 ml barium and 30 mg bisacodyl. For the colonoscopy preparation 4 l of polyethylene glycol solution was used. Participants’ experience and preference were compared using the Wilcoxon signed rank test and the chi-squared test, respectively. Associations between preference and experience parameters for the 173 participants were determined by logistic regression. Diarrhoea occurred in 94% of participants during CTC preparation. This side effect was perceived as severely or extremely burdensome by 29%. Nonetheless, the total burden was significantly lower for the CTC preparation than for colonoscopy (9% rated the CTC preparation as severely or extremely burdensome compared with 59% for colonoscopy; p < 0.001). Participants experienced significantly more pain, discomfort and total burden with the colonoscopy procedure than with CTC (p < 0.001). After 5 weeks, 69% preferred CTC, 8% were indifferent and 23% preferred colonoscopy (p < 0.001). A burdensome colonoscopy preparation and pain at colonoscopy were associated with CTC preference (p < 0.04). In conclusion, participants’ experience and preference were rated in favour of CTC with limited bowel preparation compared with full-preparation colonoscopy.

Full-laxative versus minimum-laxative fecal-tagging CT colonography using 64-detector row CT: prospective blinded comparison of diagnostic performance, tagging quality, and patient acceptance

RATIONALE AND OBJECTIVES

To compare prospectively 64-detector-row computed tomographic colonography (CTC) after a full-laxative tagging-based preparation (full preparation) with a minimum-laxative tagging-based preparation (minimum preparation) with respect to diagnostic performance in the detection of polyps, tagging quality, and patient acceptance.

MATERIALS AND METHODS

Consecutive 101 patients at high risk for developing colorectal cancer were alternately assigned to either a full preparation group (n = 51) or a minimum preparation group (n = 50) for fecal-tagging CTC. The full preparation consisted of administration of 2-L polyethylene glycol solution with 20 mL of sodium diatrizoate for fecal tagging. The minimum preparation consisted of ingestion of a total of 45 mL of sodium diatrizoate during the 3 days before and 10 mL of sodium picosulfate solution the night before CT. Colonoscopy was used as the reference standard. We assessed the accuracy of polyp detection and the tagging quality for each preparation. All patients were given questionnaires related to their acceptance.

RESULTS

Per-patient sensitivity, specificity, and positive and negative predictive values for polyps > or = 6 mm were as follows: full preparation group, 97%, 92%, 88%, and 98%, respectively; minimum preparation group, 88%, 68%, 56%, and 92%, respectively. Average visual subjective tagging scores for the full and minimum preparation groups were 94.6% and 76.1%, respectively (P < .0001). Minimum preparation was better tolerated than full preparation.

CONCLUSION

Although full-laxative and minimum-laxative fecal-tagging CTC yielded an equally high sensitivity in the detection of polyps > or = 6 mm, the full-laxative fecal-tagging CTC yielded a better specificity than did the minimum-laxative fecal-tagging CTC. Thus, it is desirable to offer patients an option of either full-laxative fecal-tagging CTC for highest diagnostic accuracy and ability to perform a same-day therapeutic colonoscopy without additional bowel preparation, or minimum-laxative fecal-tagging CTC for those unwilling to undergo full preparation but willing to accept moderate decrease in specificity.

Improving quality of colonoscopy by adding simethicone to sodium phosphate bowel preparation

AIM: To evaluate the effectiveness of simethicone in enhancing visibility and efficacy during colonoscopy.

METHODS: A prospective, double-blind, randomized, placebo-controlled study was conducted. One hundred and twenty-four patients were allocated to receive 2 doses of sodium phosphate plus 240 mg of tablet simethicone or placebo as bowel preparation. Visibility was blindly assessed for the amount of air bubbles and adequacy of colon preparation. Total colonoscopic time, side effects of the medication, endoscopist and patient satisfaction were also compared.

RESULTS: Sodium phosphate plus simethicone, compared to sodium phosphate plus placebo, improved visibility by diminishing air bubbles (100.00% vs 42.37%, P < 0.0001) but simethicone failed to demonstrate improvement in adequacy of colon preparation (90.16% vs 81.36%, P = 0.17). Endoscopist and patient satisfaction were increased significantly in the simethicone group. However, there was no difference in the total duration of colonoscopy and side effects of the medication.

CONCLUSION: The addition of simethicone is of benefit for colonoscopic bowel preparation by diminishing air bubbles, which results in enhanced visibility. Endoscopist and patient satisfaction is also increased.

Randomized study comparing two regimens of oral sodium phosphates solution versus low-dose polyethylene glycol and bisacodyl

PURPOSE

Low-volume bowel preparation regimens for colonoscopy are reported to improve patient acceptance and compliance. We sought to compare the bowel cleansing efficacy, tolerability, and acceptability of three low-volume regimens: an oral sodium phosphates solution 45/45 ml (NaP-45/45), a reduced-dose oral sodium phosphates solution 45/30 ml (NaP-45/30), and polyethylene glycol plus bisacodyl (PEG-2L).

RESULTS

A total of 121 patients were evaluated (mean age 55.2 +/- 8.9 years). Bowel cleansings rated as excellent and good were significantly different among the groups: NaP-45/45 = 98%, NaP-45/30 = 88%, and PEG-2L = 76% (P < 0.04). Side effects were not significantly different except for greater thirst in the NaP-45/45 group (P = 0.001) and increased vomiting in females using PEG-2L (two-tailed interaction, P < 0.10). Willingness to retake the preparation was higher among the sodium phosphates regimens (88, 95, and 73%, respectively; P = 0.019).

CONCLUSIONS

Better cleansing and willingness to retake the regimen was achieved with the oral sodium phosphates solutions than with polyethylene glycol plus bisacodyl.

Gastroenterologists' patient instructions for oral sodium phosphate solution for colonoscopy preparation: a survey among gastroenterologists in the state of Indiana

BACKGROUND

Oral sodium phosphate solution (OSPS) has been associated with acute renal failure when used as a bowel preparation for colonoscopy.

AIM

To determine whether gastroenterologists in Indiana follow recent recommendations for safe and effective use of colonoscopy.

METHODS

A survey of gastroenterologists in Indiana performed in mid-2006. Written instruction to patients were obtained and reviewed.

RESULTS

We received responses from 97.5% of Indiana gastroenterologists, of whom 80% reported using OSPS. All using OSPS forwarded their written instructions. None exceeded the recommended two 45 mL doses in their written instructions. Although separation of the two 45 mL doses by at least 6 to 12 hours is recommended, 35% of physicians prescribed the 2 doses at intervals less than 6 hours. Only 9.7% gave specific instructions for volumes of fluid to be taken before the first dose. Fluid prescriptions during the preparation were often suboptimal according to current recommendations. Less than 25% of physicians followed the recommendation to use carbohydrate-electrolyte solutions for hydration.

CONCLUSIONS

Gastroenterologists in Indiana in mid-2006 uniformly followed recommendations for maximum doses of OSPS, but recommended intervals for the doses and gave hydration instructions that often did not follow current recommendations.

Prospective Comparison of Three Bowel Preparation Regimens: Fleet Phosphosoda, Two-Liter and Four-Liter Electrolyte Lavage Solutions

In an attempt to improve patients’ tolerance for colon cleaning, three bowel preparation regimens: 90-mL Fleet phosphosoda (FPS), 2-L electrolyte lavage solution plus 20 mg oral bisacodyl, and 4-L lavage, were compared for efficacy and safety. A total of 912 patients were prospectively nonrandomized into three study groups. In Group A, 304 patients were given 45-mL Fleet phosphosoda at 9 AM and 6 PM the day before colonoscopy. In Group B, 304 patients were given four tablets of 5 mg bisacodyl at 12 PM the day before colonoscopy followed by 2 L electrolyte lavage by mouth at 6:00 PM the evening before colonoscopy. In Group C, 304 patients were given 4 L electrolyte lavage at 6:00 PM the evening before colonoscopy. All patients were kept on a clear liquid diet the day before colonoscopy. The bowel cleanliness was accessed by one colonoscopist. One registered nurse accessed the ease of the patient. In Group A (FPS), every patient finished the 90-mL Fleet phosphosoda. Colon cleanliness was 95.1 per cent. In Group B (2 L), three patients (0.6%) could not finish the laxative. Colon cleanliness was 95.9 per cent. In Group C (4 L), 22 patients (7.3%) could not finish the laxative preparation. Colon cleanliness was 95.3 per cent. The study found these three regimens can achieve equally good results of bowel preparation; however, the small volume laxative (FPS) has been accepted favorably by patients.

Oral colorectal cleansing preparations in adults

Bowel preparation has been a much-debated issue for both colonoscopy and for colorectal surgery. While bowel preparation for colonoscopy is clearly mandatory for optimal intraluminal visualization, bowel preparation for surgery has recently been challenged. This review evaluates oral bowel preparation, based on evidence in the literature, in order to provide a practical guide for physicians and practitioners about oral bowel cleansing preparations in current use for both colonoscopy and for colorectal surgery.A MEDLINE search, limited to publications in English language, was done through Ovid including articles published from 1966 to 2007 about bowel preparation using terms 'pre-operative care' and 'colonoscopy' or 'surgical procedure' associated with 'polyethylene glycol' and 'sodium phosphate'. The references lists from the identified articles were also included in the review. No bowel preparation method meets the ideal criteria for bowel cleansing prior to colonoscopy. However, polyethylene glycol-electrolyte lavage solution (PEG-ELS) and sodium phosphate are the most commonly used bowel preparations before colonoscopy and colon surgery. Both preparations are safely used and effective; however, some precautions should be considered, particularly with sodium phosphate. In addition, the efficacy of low-volume PEG-ELS can be improved by the addition of preparation adjuncts. Timing and dose are important considerations regardless of the method used. Mechanical bowel preparation for surgery has been questioned, and shown to have no extra benefits and possibly the association with increased morbidity. Regardless of the evidence, there are many randomized controlled trials showing the lack of benefit of mechanical bowel preparation.

Colonic lavage with two polyethylene glycol solutions prior to colonoscopy makes no difference: a prospective randomized controlled trial

OBJECTIVE

It is suggested that bowel preparations for colonoscopy are easier to tolerate when a smaller volume of solution with a more pleasant taste is used. The aim of this study was to establish equivalence between a 3-l sulphate-free polyethylene glycol solution (SF-PEG) and a 4-l PEG solution in effectiveness, patients' acceptability and tolerability.

MATERIAL AND METHODS

The study comprised 110 patients scheduled for elective colonoscopy and randomized to receive either SF-PEG or PEG. Before colonoscopy, the patients completed a questionnaire on stool frequency, medication, concomitant diseases, the amount of solution ingested, willingness to re-take it, volume of other fluid taken and tolerance of bowel preparation, taste of the laxative and occurrence of abdominal cramps. Three experienced endoscopists, blinded to the type of preparation, assigned bowel-cleansing scores using a validated 5-point scale to assess cleansing effect.

RESULTS

Data were available for 102 patients (44 M (40%), mean age 53 years, range 23-83 years). No significant differences were found in cleansing the rectosigmoid (p = 0.71) or complete colon (p = 0.79). Diverticulosis, constipation, gender and body mass index (BMI) did not influence cleansing. There was no significant difference in compliance between the two groups (p = 0.61). No differences were found for tolerance, taste and abdominal cramps. Patients who received SF-PEG had a preference for the same preparation next time in comparison with patients who had PEG cleansing (17 (33%) versus 4 (8%), respectively) (p = 0.03).

CONCLUSIONS

Both preparations are comparable in their cleansing effect and toleration. However, patients prefer cleansing with a smaller volume of solution. Improving the acceptability of colonic preparation could improve willingness to undergo colonoscopies in the future.

Is there still a role for double-contrast barium enema examination?

The role of double-contrast barium enema examination (DCBE) in screening for colorectal carcinoma has evolved considerably in recent years. This review will discuss the current indications for DCBE and contrast fluoroscopy of the colon and the anticipated future role of these studies.

Review article: Bowel preparation for colonoscopy--the importance of adequate hydration

BACKGROUND

Patient compliance with screening recommendations for colorectal cancer remains low, despite a 90% survival rate achieved with early detection. Bowel preparation is a major deterrent for patients undergoing screening colonoscopy. More than half of patients taking polyethylene glycol electrolyte lavage solution and sodium phosphate preparations experience adverse events, such as nausea and abdominal pain. Many adverse events may be associated with dehydration, including rare reports of renal toxicity in patients taking sodium phosphate products. Addressing dehydration-related safety issues through patient screening and education may improve acceptance of bowel preparations, promote compliance and increase the likelihood of a successful procedure.

AIM

To evidence safety issues associated with bowel preparation are generally related to inadequate hydration.

RESULTS

Dehydration-related complications may be avoided through proper patient screening, for example, renal function and comorbid conditions should be considered when choosing an appropriate bowel preparation. In addition, patient education regarding the importance of maintaining adequate hydration before, during and after bowel preparation may promote compliance with fluid volume recommendations and reduce the risk of dehydration-related adverse events.

CONCLUSIONS

Proper patient screening and rigorous attention by patients and healthcare providers to hydration during bowel preparation may provide a safer, more effective screening colonoscopy.

Use of a variable-stiffness colonoscope decreases the dose of patient-controlled sedation during colonoscopy: a randomized comparison of 3 colonoscopes

BACKGROUND

The variable-stiffness colonoscope incorporates different degrees of stiffness of the insertion tube, which can be adjusted during the examination. Whether its use can lead to reduced procedure-related pain and sedative use is unknown.

OBJECTIVE

Our purpose was to compare the use of 3 types of colonoscope with different shaft stiffnesses in relation to procedure-related pain and sedative consumption.

DESIGN

Prospective randomized trial.

SETTING

Endoscopy unit of a university-affiliated hospital.

PATIENTS

Consecutive patients undergoing ambulatory colonoscopy.

INTERVENTIONS

Random assignment was made of patients into 3 groups to receive colonoscopic examinations by one of the 3 types of colonoscope: conventional standard adult size, 1.3-m; 1.6-m; and the new variable-stiffness adult size, full-length (1.6-m) colonoscope. A mixture of propofol and afentanil, delivered by a patient-controlled syringe pump, was used for sedation in all groups.

MAIN OUTCOME MEASURES

Outcome measures included dose of patient-controlled sedation consumed, pain score, cecal intubation rate, cecal intubation time, requirement of abdominal pressure and change of patients' positions during colonoscopy, and endoscopists and patients' satisfaction scores according to a visual analog scale.

RESULTS

A total of 335 patients were randomized. Patients in group 3 used significantly less propofol (in milligrams per kilograms, mean [SD]) compared with the other 2 groups (group 1: 1.00 [0.75], group 2: 0.93 [0.62], and group 3: 0.75 [0.65]; P = .02; 1-way analysis of variance). The mean (SD) pain score was also lower in group 3.

LIMITATIONS

The endoscopists were not blinded.

CONCLUSION

The use of the new variable-stiffness adult-size colonoscope significantly reduced procedure-related pain and doses of sedative medications during colonoscopy.

Systematic review: oral bowel preparation for colonoscopy

BACKGROUND

There are many published trials of colon cleansing regimens for colonoscopy but no clear consensus regarding relative performance.

AIM

To identify high quality controlled trials comparing two or more bowel preparation regimens and to compare efficacy and tolerability.

METHODS

A comprehensive systematic review was carried out to identify candidate studies. Quality appraisal was carried out on all identified studies. Results were meta-analysed where possible and qualitatively compared if not.

RESULTS

Eighty-two studies qualified for analysis. Polyethylene glycol and sodium phosphate were the most frequently investigated preparations. There was no significant efficacy difference between the two, but sodium phosphate was better tolerated. Sodium picosulphate/magnesium citrate, a commonly prescribed preparation, was investigated in four studies, with no clear benefit over other regimens demonstrated. Safety was not recognized as a problem in the randomized controlled trials. Published case series demonstrate that sodium phosphate is associated with the highest risk of clinically significant electrolyte disturbances.

CONCLUSION

Shortcomings in study design limit the value of many of the studies. Based on these results, no single bowel preparation emerges as consistently superior. New preparations are required that combine better efficacy and tolerability, in addition to rigorous new validated study designs, allowing unequivocal comparisons to be made.

The impact of colon preparation timing on colonoscopic detection of colorectal neoplasms--a prospective endoscopist-blinded randomized trial

OBJECTIVES

Timing of colon preparation might influence the cleansing condition of the colon and therefore affect the quality and diagnostic yield of colonoscopy. This study compared two different timings of colon preparation to assess the efficacy of colon cleansing and diagnostic yield of colorectal neoplasms during colonoscopy.

METHODS

One hundred twenty-one eligible subjects who had colorectal neoplasms detected at a screening colonoscopy were randomly assigned to receive colon preparation with polyethylene glycol electrolyte lavage solution (PEG-ELS) either on the day of (on the day group) or the night before (previous night group) a second colonoscopy. The condition of colon preparation and the diagnostic yield of colorectal neoplasms were recorded and compared between the two groups for the initial and second colonoscopies.

RESULTS

Fifty-nine subjects received colon preparation on the night before and 60 subjects received colon preparation the day of a second colonoscopy. Colon preparation for the second colonoscopy was better in the on-the-day group than in the previous night group (P= 0.003). Colon preparation for the second colonoscopy was better for each group in comparison with the initial colonoscopy (P < 0.0001). An interobserver variability analysis using 20 randomly selected colonoscopies from the two groups revealed good correlation among four colonoscopists. More lesions were detected in group A during the second colonoscopy (P= 0.028).

CONCLUSION

Colon preparation on the day of colonoscopy has a better cleansing quality and higher diagnostic yield. Subjects who had lesions detected during the initial screening colonoscopy had better colon cleansing for the second colonoscopy regardless of the timing of preparation.

Comparison of Reduced Volume versus Four-Liter Electrolyte Lavage Solutions for Colon Cleansing

In an attempt to improve patient tolerance for colon cleaning, a reduced-volume regimen with a 2-liter electrolyte lavage solution plus 20 mg of oral bisacodyl was compared with the standard 4-liter lavage for efficacy and safety. Three hundred patients were prospectively randomized into two study groups. One group of 150 patients was given four tablets of 5 mg bisacodyl at 12:00 PM the day before their colonoscopy, followed by 2 liters of electrolyte lavage by mouth at 6:00 PM the evening before their colonoscopy. Another group of 150 patients were given 4 liters of electrolyte lavage at 6:00 PM the evening before their colonoscopy. All patients were on a clear liquid diet the day before their colonoscopy. No enema was given in either groups. The bowel cleanliness was accessed by one colonoscopist. One registered nurse accessed the comfort of patient. In the 2-liter group, only one (0.6%) patient could not finish the laxative. Colon cleanliness was 80 per cent to 100 per cent, with an average of 95.9 per cent. In the 4-liter group, 11 (7.3%) patients could not finish the laxative preparation. Colon cleanliness was 78 per cent to 100 per cent, with an average of 95.3 per cent. The study that found the 2-liter electrolyte lavage solution with four tablets of bisacodyl can achieve equally good results in bowel preparation and favorable acceptance by patients compared with the 4-liter lavage.

A randomized prospective trial comparing different regimens of oral sodium phosphate and polyethylene glycol-based lavage solution in the preparation of patients for colonoscopy

BACKGROUND

Regulatory agencies have warned clinicians regarding the risk of electrolyte abnormalities if more than two 45-mL bottles of oral sodium phosphate (NaP) solution are administered within a 24-hour period.

OBJECTIVE

To compare the efficacy, safety, and tolerability of different regimens of oral NaP and polyethylene glycol (PEG).

DESIGN

Randomized controlled trial.

SETTING

Teaching hospital outpatient endoscopy clinic.

PATIENTS

Two hundred outpatients without comorbidities who underwent routine colonoscopy.

INTERVENTIONS

Two bottles of NaP, 6, 12, or 24 hours apart; or 4 L PEG.

MAIN OUTCOME MEASUREMENTS

Bowel preparation quality, patient tolerability, and electrolyte changes.

RESULTS

The 12- and 24-hour NaP achieved better cleansing than the 6-hour NaP or PEG. Only 8.5% and 8.3% of patients in the 24- and 12-hour NaP had poor preparations, respectively, compared with 15.6% and 23.4% in the 6-hour NaP and PEG, respectively. The poorer preparation scores with PEG were partly because of a greater amount of colonic fluid. There were no relevant electrolyte changes with PEG, whereas hypokalemia, hypocalcemia, or hyperphosphatemia developed in 5% to 57% of patients on NaP. All regimens were poorly tolerated by patients.

LIMITATIONS

The study was likely underpowered to detect small group differences in electrolytes.

CONCLUSIONS

A 24- or 12-hour NaP bowel preparation strategy was more effective than NaP 6 hours apart or PEG. PEG use is associated with more residual colonic fluid but represents an alternative to NaP in some clinical situations.

Combined low volume polyethylene glycol solution plus stimulant laxatives versus standard volume polyethylene glycol solution: a prospective, randomized study of colon cleansing before colonoscopy

INTRODUCTION

The effectiveness of polyethylene glycol solutions (PEG) for colon cleansing is often limited by the inability of patients to drink adequate portions of the 4 L solution. The aim of the present study was to determine whether a reduced volume of PEG combined with stimulant laxatives would be better tolerated and as or more effective than the standard dose.

METHODS

Patients undergoing outpatient colonoscopy were randomly assigned to receive either low-volume PEG plus sennosides (120 mg oral sennosides syrup followed by 2 L PEG) or the standard volume preparation (4 L PEG). The subjects rated the tolerability of the preparations and their symptoms. Colonoscopists were blind to the colonic cleansing preparation and graded the cleansing efficacy using a validated tool (the Ottawa scale).

RESULTS

The low-volume PEG plus sennosides preparation was significantly better tolerated than the standard large volume PEG (P<0.001) but was less efficacious (P=0.03). Thirty-eight per cent of patients in the large volume PEG group were unable to finish the preparation, compared with only 6% in the reduced volume group. There were no adverse events reported.

CONCLUSIONS

Although the low-volume PEG plus sennosides preparation was better tolerated, it was not as effective as standard large-volume PEG. However, in view of the significant difference in tolerance, further research investigating possible improvements in the reduced-volume regimen seems warranted.

CT colonography in a Korean population with a high residue diet: Comparison between wet and dry preparations

AIM

To compare wet and dry preparation methods for computed tomography colonography (CTC) in terms of preparation quality, interpretation time, and diagnostic performance for polyp detection in a population with a high residue diet.

MATERIALS AND METHODS

Eighty-six patients were divided into two groups. Group 1 (n=24) received a wet preparation of 4l polyethylene glycol (PEG) solution, and group 2 (n=62) received a dry preparation of phosphor-soda. Abnormal findings, including polyps, and the time required to interpret the CTC images in both groups were documented by a radiologist. CTC findings were compared to those of colonoscopy as a reference standard. Two radiologists evaluated the quality of CTC with regard to residual fluid, faeces, and colonic distension using a four-point scale in consensus. Statistical differences for residual fluid, faeces, distensibility on CTC, and interpretation time between the two groups were analysed. The diagnostic performance of CTC in both groups was also compared.

RESULTS

One-hundred and ninety polyps in 70 patients were identified using colonoscopy. Regarding the quality of images produced the wet preparation was significantly better than the dry preparation (p<0.05). The average interpretation time was significantly shorter for the wet group (11.7 min) than the dry group (16.4 min) (p<0.05). For per-patient analysis, the positive predictive value (PPV) was significantly better for the wet (100%) than the dry group (79.6%; p=0.025). Sensitivities and PPV for >or=10 mm polyps were comparable between two groups (p>0.05).

CONCLUSION

In a population with a high-residue diet, CTC with wet preparation can be interpreted in a time-efficient manner and is comparable with CTC with dry preparation.

Which is the optimal bowel preparation for colonoscopy - a meta-analysis

OBJECTIVE

To assess which bowel preparation agent is most effective.

METHODS

A search of randomized trials between January 1990 and July 2005 was obtained, using MEDLINE and PubMed databases, and the Cochrane Central Register of Controlled Trials. Meta-analysis was performed using the Forest plot review.

RESULTS

Sodium phosphate (NaP) was more effective in bowel cleansing than polyethylene glycol (PEG) - odds ratio 0.75 (95%CI: 0.65-0.88; P = 0.0004); and sodium picosulphate (SPS) - odds ratio 0.52 (95%CI: 0.34-0.81; P = 0.004). PEG and SPS were comparable in bowel cleansing ability, odds ratio 1.69 (95%CI: 0.92-3.13; P = 0.09). NaP was more easily completed by patients compared to PEG, odds ratio 0.16 (95%CI: 0.09-0.29; P < 0.00001). More patients were able to complete SPS than PEG, but this was not statistically significant - odds ratio 0.56 (95%CI: 0.28-1.13; P = 0.11). NaP and PEG were comparable in terms of adverse events, odds ratio 0.98 (95%CI: 0.82-1.17; P = 0.81), although NaP resulted in more asymptomatic hypokalaemia and hyperphosphataemia. NaP and SPS appeared to have similar incidence of adverse events. PEG resulted in more adverse events than SPS, odds ratio 3.82 (95%CI: 1.60-9.15; P = 0.003).

CONCLUSIONS

NaP was more effective in bowel cleansing than PEG or SPS and was comparable in terms of adverse events. Patients have more difficulty completing PEG than NaP and SPS. Biochemical changes associated with a small-volume preparation like NaP, albeit largely asymptomatic, mandate caution in patients with cardiovascular or renal impairment.

Prospective randomized comparison of oral sodium phosphate and polyethylene glycol lavage for colonoscopy preparation

AIM

To compare the effectiveness, patient acceptability, and physical tolerability of two oral lavage solutions prior to colonoscopy in a Taiwanese population.

METHODS

Eighty consecutive patients were randomized to receive either standard 4 L of polyethylene glycol (PEG) or 90 mL of sodium phosphate (NaP) in a split regimen of two 45 mL doses separated by 12 h, prior to colonoscopic evaluation. The primary endpoint was the percent of subjects who had completed the preparation. Secondary endpoints included colonic cleansing evaluated with an overall assessment and segmental evaluation, the tolerance and acceptability assessed by a self-administered structured questionnaire, and a safety profile such as any unexpected adverse events, electrolyte tests, physical exams, vital signs, and body weights.

RESULTS

A significantly higher completion rate was found in the NaP group compared to the PEG group (84.2% vs 27.5%, P<0.001). The amount of fluid suctioned was significantly less in patients taking NaP vs PEG (50.13+/-54.8 cc vs 121.13+/-115.4 cc, P<0.001), even after controlling for completion of the oral solution (P = 0.031). The two groups showed a comparable overall assessment of bowel preparation with a rate of "good" or "excellent" in 78.9% of patients in the NaP group and 82.5% in PEG group (P = 0.778). Patients taking NaP tended to have significantly better colonic segmental cleansing relative to stool amount observed in the descending (94.7% vs 70%, P = 0.007) and transverse (94.6% vs 74.4%, P = 0.025) colon. Slightly more patients graded the taste of NaP as "good" or "very good" compared to the PEG patients (32.5% vs 12.5%; P = 0.059). Patients' willingness to take the same preparation in the future was 68.4% in the NaP compared to 75% in the PEG group (P = 0.617). There was a significant increase in serum sodium and a significant decrease in phosphate and chloride levels in NaP group on the day following the colonoscopy without any clinical sequelae. Prolonged (>24 h) hemodynamic changes were also observed in 20-35% subjects of either group.

CONCLUSION

Both bowel cleansing agents proved to be similar in safety and effectiveness, while NaP appeared to be more cost-effective. After identifying and excluding patients with potential risk factors, sodium phosphate should become an alternative preparation for patients undergoing elective colonoscopy in the Taiwanese population.

A prospective randomized blinded comparison of sodium phosphate and polyethylene glycol-electrolyte solution for safe bowel cleansing

BACKGROUND

Polyethylene glycol-electrolyte solution (PEG-ELS) is routinely prescribed for bowel cleansing. Sodium phosphate (NaP) may be an effective but potentially hazardous alternative.

AIM

To investigate the safety of prescription of either agent, without being informed of the patient's medical history.

METHODS

One hundred consecutive patients were randomly allocated to PEG-ELS or NaP. Prior to and after the bowel cleansing, blood was sampled for renal function and electrolytes. Patients answered questionnaires about complaints and ease of intake, and endoscopists rated the quality of bowel preparation.

RESULTS

Eleven patients were identified with a theoretical contraindication for NaP, of whom nine should have been discovered by taking a detailed clinical history. Actually, six of them received NaP with a doubling of serum phosphate levels or hypokalaemia in four. In subjects without a contraindication to the use of NaP, hyperphosphataemia developed in 39% and hypocalcaemia in 5%. Patients tolerated NaP better and completed the preparation more often. Endoscopists rated the quality of bowel preparation equivalent, except for a better cleansed ascending colon with PEG-ELS.

CONCLUSIONS

The 11% potentially hazardous allocation to NaP and the 39% incidence of hyperphosphataemia with NaP do not justify an 'over-the-counter' prescription. Taking a detailed history and, when in doubt, using PEG-ELS will safeguard against inappropriate administration of NaP.

Is blinding the endoscopists to bowel preparations in randomized-controlled trials a reality?

BACKGROUND

A number of studies compared the quality, efficacy and tolerability of oral sodium phosphate (NaP) and polyethylene glycol (PEG)-based solutions in preparation for colonoscopy. The primary aim of this study was to explore whether endoscopists can be effectively blinded to the type of bowel preparation.

METHODS

We recruited 3 experienced endoscopists and 57 outpatients (18-65 years old) undergoing colonoscopy. We randomized eligible patients to receive one of the two bowel preparations. Endoscopists who performed the tests were blinded to the type of preparation, and made their best judgment on the type and quality of the bowel preparation.

RESULTS

Forty-five patients completed the study. The overall correct estimation of the type of bowel preparation was 60.0% (95% CI; 45.5%, 73.0%). The cleansing quality did not differ between the two preparations. Patients found oral NaP solution much easier to take (81.8% versus 36.4%; P = 0.005) and the PEG-based group tended to have more nausea or vomiting. 47.6% of patients in the PEG group indicated they would prefer to try another bowel preparation in the future compared to 4.5% in the oral NaP group (P = 0.002). We stopped the study after an interim analysis indicating that more than 600 patients would be required to detect statistically significant differences in the primary aim.

CONCLUSION

Our findings suggest that blinding of endoscopists in clinical trials comparing oral NaP to PEG had a relatively low likelihood of bias. The study also suggests that oral NaP is easier to take and more tolerable than PEG without impairing cleansing quality.

Spasmolysis at CT colonography: butyl scopolamine versus glucagon

PURPOSE

To retrospectively determine if the use of butyl scopolamine or glucagon in the supine patient improves colonic distention and reduces the number of collapsed intestinal segments at computed tomographic (CT) colonography.

MATERIALS AND METHODS

This study had institutional review board approval; subject informed consent was not required. CT colonography was performed without the administration of an intravenous spasmolytic in 80 asymptomatic subjects (group 1; 45 women, 35 men; age range, 48-77 years; mean, 61.9 years). These subjects were matched with two groups of 80 subjects who were similar in age but were premedicated with glucagon (group 2; 41 women, 39 men; age range, 43-76 years; mean, 63.1 years) or butyl scopolamine (group 3; 43 women, 37 men; age range, 34-77 years; mean, 63.4 years). All 240 subjects were examined in the supine position with multisection CT and a section thickness of 1 mm after intravenous contrast agent administration and rectal carbon dioxide insufflation. The colon was divided into seven segments, and the colon length, total volume, radial distensibility, and number of non-distended segments were calculated for each subject and compared among the three groups. Statistical analysis was performed with analysis of variance and chi2 testing.

RESULTS

Mean bowel length was not significantly different among the groups. Mean colon volumes and radial distensibilities, respectively, were 1.84 L and 3.69 cm in group 1, 2.14 L and 3.98 cm in group 2, and 2.35 L and 4.23 cm in group 3; differences in colon volume and radial distensibility were significant only between group 1 and group 3 (P < .001). At CT colonography, 29 segments in 20 group 1 subjects were collapsed, 23 segments in 12 group 2 subjects were collapsed, and 11 segments in six group 3 subjects were collapsed (P = .016).

CONCLUSION

Premedication with butyl scopolamine or, less effectively, glucagon improves colonic distention in the supine subject.