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Physiologic Effects of Bowel Preparation

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Diseases of the Colon & Rectum


Despite the universal use of bowel preparation before colonoscopy and colorectal surgery, the physiologic effects have not been described in a standardized setting. This study was designed to investigate the physiologic effects of bowel preparation.


In a prospective study, 12 healthy volunteers (median age, 63 years) underwent bowel preparation with bisacodyl and sodium phosphate. Fluid and food intake were standardized according to weight, providing adequate calorie and oral fluid intake. Before and after bowel preparation, weight, exercise capacity, orthostatic tolerance, plasma and extracellular volume, balance function, and biochemical parameters were measured.


Bowel preparation led to a significant decrease in exercise capacity (median, 9 percent) and weight (median, 1.2 kg). Plasma osmolality was significantly increased from 287 to 290 mmol kg−1, as well as increased phosphate and urea concentrations, whereas calcium and potassium concentrations decreased significantly after bowel preparation. No differences in plasma or extracellular volumes were seen. Orthostatic tolerance and balance function did not change after bowel preparation.


Bowel preparation has significant adverse physiologic effects, which may be attributed to dehydration. The majority of these findings is small and may not be of clinical relevance in otherwise healthy patients undergoing bowel preparation and following recommendations for oral fluid intake.

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  1. O Zmora AJ Pikarsky SD Wexner (2001) ArticleTitleBowel preparation for colorectal surgery Dis Colon Rectum 44 1537–49 Occurrence Handle1:STN:280:DC%2BD3MrltFaltg%3D%3D Occurrence Handle11598488

    CAS  PubMed  Google Scholar 

  2. E Kutt MJ Hall A Booth J Virjee (1988) ArticleTitleBarium enemas are a headache Clin Radiol 39 9–10 Occurrence Handle1:STN:280:BieC3M%2Fis1w%3D Occurrence Handle3338244

    CAS  PubMed  Google Scholar 

  3. P Barker T Trotter C Hanning (1992) ArticleTitleA study of the effect of Picolax on body weight, cardiovascular variables and haemoglobin concentration Ann R Coll Surg Engl 74 318–9 Occurrence Handle1:STN:280:ByyD3sjhtVY%3D Occurrence Handle1416702

    CAS  PubMed  Google Scholar 

  4. M Kjaersgaard C Lie T Bisgaard H Kehlet J Rosenberg (2000) ArticleTitleEffect of oxygen on postoperative cardiovascular response to exercise Eur J Surg 166 915–9 Occurrence Handle1:STN:280:DC%2BD3M7ltlWgug%3D%3D Occurrence Handle11152249

    CAS  PubMed  Google Scholar 

  5. K Holte P Jensen H Kehlet (2003) ArticleTitlePhysiologic effects of intravenous fluid administration in healthy volunteers Anesth Analg 96 1504–9 Occurrence Handle12707158

    PubMed  Google Scholar 

  6. J Brochner-Mortensen (1972) ArticleTitleA simple method for the determination of glomerular filtration rate Scand J Clin Lab Invest 30 271–4 Occurrence Handle1:CAS:528:DyaE3sXis1Sgsw%3D%3D Occurrence Handle4629674

    CAS  PubMed  Google Scholar 

  7. J Brochner-Mortensen (1980) ArticleTitleA simple single injection method for determination of the extracellular fluid volume Scand J Clin Lab Invest 40 567–73 Occurrence Handle1:STN:280:Bi6D2sflslw%3D Occurrence Handle6777859

    CAS  PubMed  Google Scholar 

  8. DA Lieberman J Ghormley K Flora (1996) ArticleTitleEffect of oral sodium phosphate colon preparation on serum electrolytes in patients with normal serum creatinine Gastrointest Endosc 43 467–9 Occurrence Handle1:STN:280:BymA38noslM%3D Occurrence Handle8726759

    CAS  PubMed  Google Scholar 

  9. JA Dipalma SE Buckley BA Warner RM Culpepper (1996) ArticleTitleBiochemical effects of oral sodium phosphate Dig Dis Sci 41 749–53 Occurrence Handle1:CAS:528:DyaK28XivF2jt7w%3D Occurrence Handle8674396

    CAS  PubMed  Google Scholar 

  10. TK Toledo JA Dipalma (2001) ArticleTitleColon cleansing preparation for gastrointestinal procedures Aliment Pharmacol Ther 15 605–11 Occurrence Handle1:STN:280:DC%2BD38%2FgvFWgug%3D%3D Occurrence Handle11328253

    CAS  PubMed  Google Scholar 

  11. G Sanders SJ Mercer K Saeb-Parsey MA Akhavani KB Hosie AW Lambert (2001) ArticleTitleRandomized clinical trial of intravenous fluid replacement during bowel preparation for surgery Br J Surg 88 1363–5 Occurrence Handle1:STN:280:DC%2BD3Mrjt1Smsg%3D%3D Occurrence Handle11578293

    CAS  PubMed  Google Scholar 

  12. T Huynh S Vanner W Paterson (1995) ArticleTitleSafety profile of 5-h oral sodium phosphate regimen for colonoscopy cleansing: lack of clinically significant hypocalcemia or hypovolemia Am J Gastroenterol 90 104–7 Occurrence Handle1:STN:280:ByqC3c%2FhsFw%3D Occurrence Handle7801907

    CAS  PubMed  Google Scholar 

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Correspondence to Kathrine Holte M.D..

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Supported by grants from the University of Copenhagen and the Danish Research Council (no. 22-01-0160).

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Holte, K., Nielsen, K., Madsen, J. et al. Physiologic Effects of Bowel Preparation. Dis Colon Rectum 47, 1397–1402 (2004).

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