Randomized Controlled Trial: Split-dose and Same-day Large Volume Bowel Preparation for Afternoon Colonoscopy Have Similar Quality of Preparation

Abstract

Goals: We compare bowel cleanliness in patients taking same-day versus split-dose 4-L polyethylene glycol laxative for afternoon colonoscopy. Secondary objectives included patient satisfaction, adverse effects and patient tolerability. Background: Afternoon colonoscopies have been associated with inadequate bowel preparation and lower adenoma detection rates. Same-day (morning) or split-dosing of the laxative have improved preparation quality but differences between these options are unclear. Materials and methods: Single-center prospective randomized endoscopist blinded trial. Patients aged 18 years and above prescribed 4-L polyethylene glycol for colonoscopy were randomized into same-day or split-dose preparation. Preparation quality was assessed using the Ottawa Bowel Preparation Scale. Patient satisfaction and side effects was collected using a questionnaire. Intention-to-treat and per-protocol analysis were performed. Results: A total of 300 patients (158 split-dose, 142 same-day) were evaluated. No statistically significant difference was seen on total Ottawa score among the groups (P=0.47) or by individual colonic segments in intent-to-treat and per-protocol analysis. Patients in split-dose group were more likely to complete the entire preparation (P=0.01) but reported more sleep loss (P=0.001). The same-day preparation group reported higher incidence of vomiting (P=0.036). Patients ingesting bowel preparation ≥7 hours before colonoscopy had higher total Ottawa scores (P=0.001). Conclusions: There were no differences in quality of preparation in patients taking same-day versus split-dose preparation for afternoon colonoscopy. Those receiving same-day preparation were less likely to lose sleep but more likely to have emesis. These differences should be considered when selecting a bowel preparation regimen.

Same-day single-dose vs large-volume split-dose regimens of polyethylene glycol for bowel preparation: A systematic review and meta-analysis

“…Table 1 summarizes the characteristics of the 18 included studies ( n = 5464), which consisted of 2793 patients who received SSDs and 2671 patients who received the SpDs regimen. Nine trials evaluated low-volume (2 L) SSD PEG with adjuvant laxative use vs large-volume(≥ 3 L) SpDs PEG[ 11 , 12 , 22 - 28 ], four trials compared 4 L SSD PEG vs 4 L SpDs PEG[ 13 , 14 , 19 , 20 ], and six trials compared 2 L SSD PEG vs (≥ 3 L) SpDs PEG[ 11 , 15 - 18 , 21 ]. Interestingly, in a study by Zhang et al [ 11 ], patients were assigned to three groups: 2 L SSD PEG, 2 L SSD PEG with adjuvant laxative (linaclotide) and 4 L SpDs PEG.…”

“…Bowel cleanliness was evaluated either with BBPS[ 11 , 12 , 14 , 15 , 18 , 23 - 27 ] or OBPS[ 13 , 16 , 17 , 19 - 22 , 28 ]. An adequate bowel preparation was defined as a total BBPS score ≥ 6 with all colon segments scores ≥ 2, or a total OBPS score < 5 (including score < 7 by De Leone, score ≤ 3 by Cesaro) or all colon segment OBPS score < 2.…”

“…An adequate bowel preparation was defined as a total BBPS score ≥ 6 with all colon segments scores ≥ 2, or a total OBPS score < 5 (including score < 7 by De Leone, score ≤ 3 by Cesaro) or all colon segment OBPS score < 2. Diet restriction was mentioned in 16 trials and consisted of low residual diet/low-fiber foods[ 11 , 14 - 16 , 20 - 25 , 27 - 28 ] or clear liquid diet[ 13 , 15 , 17 , 19 , 26 , 28 ] before colonoscopy. Colonoscopy was performed with optimal preparation-to-colonoscopy (PC) interval time in only 6 trials[ 11 , 12 , 15 , 16 , 21 , 24 ], while 9 trials did not mention the PC interval[ 13 , 14 , 20 , 22 , 23 , 25 - 28 ].…”

The unmet needs for identifying the ideal bowel preparation

“…Several studies have showed no substantial differences between split‐dose and same‐day schedules. 39 , 40 , 41 , 42 However, the schedule chosen should be based on the patient's clinical characteristics, including comorbidities, concomitant medications, and hospitalization, and socioeconomic status. 41 , 43 …”

“… 39 , 40 , 41 , 42 However, the schedule chosen should be based on the patient's clinical characteristics, including comorbidities, concomitant medications, and hospitalization, and socioeconomic status. 41 , 43 …”