EP.TH.299Is peritoneal lavage with water the optimal washout as a preventative method for peritoneal disease following colorectal cancer resection? A systematic review

Aim To study available data on the advantages of peritoneal lavage with distilled water following colorectal cancer resection in improving overall patient outcomes Methods PubMed, Google Scholar, and Cochrane databases were searched until October 2020. References from relevant articles were reviewed to widen the search. Results Overall, 3 experimental studies were identified. Water was found to be superior to other peritoneal lavage solutions in inducing tumorigenic cell lysis in vitro. Mice who underwent peritoneal lavage with water survived longer and had a significantly reduced peritoneal tumour burden compared to mice who did not undergo lavage or those treated with saline lavage solution. Peritoneal secretions were found to contaminate water lavage and reduce its cell-lytic effect. Nonetheless, complete cell lysis was achieved, in vivo, by prolonging the time of cell exposure to contaminated lavage solution by 20 min. Conclusion Single peritoneal lavage with water is probably safe and may have a positive influence on patient outcomes. Further evidence is required to regard sequential peritoneal lavages with water as beneficial and safe in humans.

A Chinese Survey of Current Practice Patterns of Preoperative Bowel Preparation in Colorectal Surgery

Background Bowel preparation has long been considered as the standard preoperative management for colorectal surgery. However, there are still controversies about bowel preparation and the importance of bowel preparation gradually declined. The purpose of this study is to describe the current attitudes and practice patterns of preoperative bowel preparation among Chinese surgeons. Methods An online 11-question anonymous survey was randomly assigned to Chinese surgeons. The questionnaire sought information on each surgeon’s current practice of preoperative bowel preparation. Results 384 Chinese surgeons from 26 provincial administrative regions took part in this survey. The most common reason for choosing bowel preparation was preventing surgical site infection (SSI). Meanwhile, 74% Chinese surgeons believed bowel preparation could avoid anastomotic leakage. Only 34% thought that bowel preparation was considered to reduce risk of postoperative bleeding. In terms of bowel preparation methods, 57% Chinese surgeons preferred to choose laxatives alone. Regarding the choices of agents, Chinese surgeons were more likely to choose polyethylene glycol-electrolyte lavage solution (PEG-ELS). Conclusions Surgeons choose bowel preparation mostly to avoid SSI and anastomotic leakage, and they prefer using laxatives alone. Our study shows that surgeons do not have clear guidelines that can govern their clinical practice and there are still controversies about bowel preparation. Further study is required to provide strong evidences to inform clinical and policy decisions.

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

Our aim was to evaluate efficacy and safety of 30mL CaO alone or plus Asc in bowel preparation before colonoscopy. Two hundred and forty six patients were allocated randomly to ingest 2L PEG with 30mL CaO, 1L PEG with 30mL CaO plus 5g Asc, or 3L 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). 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 were higher in 2L PEG-CaO (P = 0.016) and 1L PEG-CaO-Asc groups (P = 0·017). Patients’ compliance was 67.5%, 71.4% and 80.5% in 3L PEG, 2L PEG-CaO and 1L PEG-CaO-Asc groups (P = 0.014). Adequate bowel preparation rate was 75%, 78.57% and 53.66% in 3L PEG, 2L PEG-CaO and 1L PEG-CaO-Asc groups (P = 0.021). There were no differences in terms of remaining outcomes. Despite an increase in patients’ satisfaction and compliance, 1L PEG-CaO-Asc significantly decreased adequate bowel preparation rate. However, 2L PEG-CaO improved the patients' satisfaction and compliance and increased adequate bowel preparation rate.

Tracheal acid or surfactant instillation raises alveolar surface tension

Whether alveolar liquid surface tension, T, is elevated in the acute respiratory distress syndrome (ARDS) has not been demonstrated in situ in the lungs. Neither is it known how exogenous surfactant, which has failed to treat ARDS, affects in situ T. We aim to determine T in an acid-aspiration ARDS model before and after exogenous surfactant administration. In isolated rat lungs, we combine servo-nulling pressure measurement and confocal microscopy to determine alveolar liquid T according to the Laplace relation. Administering 0.01 N (pH 1.9) HCl solution by alveolar injection or tracheal instillation, to model gastric liquid aspiration, raises T. Subsequent surfactant administration fails to normalize T. Furthermore, in normal lungs, tracheal instillation of control saline or exogenous surfactant raises T. Lavaging the trachea with saline and injecting the lavage solution into the alveolus raises T, suggesting that tracheal instillation may wash T-raising airway contents to the alveolus. Adding 0.01 N HCl or 5 mM CaCl2—either of which aggregates mucins—to tracheal lavage solution reduces or eliminates the effect of lavage solution on alveolar T. Following tracheal saline instillation, liquid suctioned directly out of alveoli through a micropipette contains mucins. Additionally, alveolar injection of gastric mucin solution raises T. We conclude that 1) tracheal liquid instillation likely washes T-raising mucins to the alveolus and 2) even exogenous surfactant that could be delivered mucin-free to the alveolus might not normalize T in acid-aspiration ARDS. NEW & NOTEWORTHY We demonstrate in situ in isolated lungs that surface tension is elevated in an acid-aspiration acute respiratory distress syndrome (ARDS) model. Following tracheal liquid instillation, also in isolated lungs, we directly sample alveolar liquid. We find that liquid instillation into normal lungs washes mucins to the alveolus, thereby raising alveolar surface tension. Furthermore, even if exogenous surfactant could be delivered mucin-free to the alveolus, exogenous surfactant might fail to normalize alveolar surface tension in acid-aspiration ARDS.

Optimal intake of clear liquids during preparation for afternoon colonoscopy with low-volume polyethylene glycol plus ascorbic acid

Background and study aims The standard colonoscopy preparation regimen in Japan for afternoon procedures is sequential intake of 1 L of polyethylene glycol electrolyte lavage solution containing ascorbic acid (PEG-ASC), 0.5 L of clear liquid, 0.5 L of PEG-ASC, and finally 0.25 L of clear fluids (all at a rate of 0.25 L every 15 min). However, this regimen seems poorly tolerated and complicated for many patients compared to previous regimen of polyethylene glycol electrolyte lavage solution. The aim of this study was to evaluate an alternate regimen of 0.5 L of PEG-ASC followed by 0.25 L clear liquids, repeated 3 times. Patients and methods This was a single-blinded, non-inferiority, randomized controlled study. Subjects were randomized to the standard regimen or the alternate regimen using a web-based registry system. All patients were instructed to eat a pre-packaged, low residue diet and to take sodium picosulfate hydrate the day before colonoscopy. The Boston Bowel Preparation Scale was used to evaluate bowel cleansing, and a 3-point scale was used to assess mucosal visibility. The primary endpoint was successful bowel cleansing. The acceptability, tolerability, safety, and endoscopic findings of these two regimens were secondary endpoints. Results A total of 409 patients were randomized to either the standard regimen (n = 204, males 54.0 %, mean age 65.5 years) or the alternate regimen (n = 205, 54.6 %, 65.0 years). The rates of successful bowel cleansing were 71.1 % (64.3 – 77.2 %) with the standard regimen vs. 75.1 % (68.6 – 80.9 %) with the alternate regimen (95 % lower confidence limit, for the difference = – 4.6, non-inferiority P < 0.05). No significant differences were found in tolerability, safety, and endoscopic findings. Conclusion The alternate regimen and standard regimen are clinically equivalent with respect to cleansing efficacy and acceptability, tolerability, safety, and endoscopic findings. These results are good news for patients with difficulty drinking the first liter of PEG-ASC.