Endoscopy 2010; 42(9): 736-741
DOI: 10.1055/s-0030-1255615
Original article

© Georg Thieme Verlag KG Stuttgart · New York

Air suctioning during colon biopsy forceps removal reduces bacterial air contamination in the endoscopy suite

S.  R.  Vavricka1 [*] , R.  Tutuian1 , A.  Imhof2 , S.  Wildi3 , C.  Gubler1 , H.  Fruehauf1 , C.  Ruef2 , A.  M.  Schoepfer4 , 5 [*] , M.  Fried1 [*]
  • 1Division of Gastroenterology and Hepatology, Department of Internal Medicine, University Hospital of Zurich, Zurich, Switzerland
  • 2Division of Infectious Diseases, Department of Internal Medicine, University Hospital of Zurich, Zurich, Switzerland
  • 3Division of Gastroenterology and Hepatology, Department of Internal Medicine, Cantonal Hospital, Winterthur, Switzerland
  • 4Farncombe Family Institute of Digestive Health Research, McMaster University, Hamilton, Ontario, Canada
  • 5Department of Visceral Surgery and Medicine, Gastroenterology, Inselspital/Bern University Hospital, Bern, Switzerland
Further Information

Publication History

submitted 29 January 2010

accepted after revision 25 May 2010

Publication Date:
30 August 2010 (online)

Background and study aims: Bacterial contamination of endoscopy suites is of concern; however studies evaluating bacterial aerosols are lacking. We aimed to determine the effectiveness of air suctioning during removal of biopsy forceps in reducing bacterial air contamination.

Patients and methods: This was a prospective single-blinded trial involving 50 patients who were undergoing elective nontherapeutic colonoscopy. During colonoscopy, endoscopists removed the biopsy forceps first without and then with suctioning following contact with the sigmoid mucosa. A total of 50 L of air was collected continuously for 30 seconds at 30-cm distance from the biopsy channel valve of the colonoscope, with time starting at forceps removal. Airborne bacteria were collected by an impactor air sampler (MAS-100). Standard Petri dishes with CNA blood agar were used to culture Gram-positive bacteria. Main outcome measure was the bacterial load in endoscopy room air.

Results: At the beginning and end of the daily colonoscopy program, the median (and interquartile [IQR] range) bioaerosol burden was 4 colony forming units (CFU)/m3 (IQR 3 – 6) and 16 CFU/m3 (IQR 13 – 18), respectively. Air suctioning during removal of the biopsy forceps reduced the bioaerosol burden from a median of 14 CFU/m3 (IQR 11 – 29) to a median of 7 CFU/m3 (IQR 4 – 16) (P = 0.0001). Predominantly enterococci were identified on the agar plates.

Conclusion: The bacterial aerosol burden during handling of biopsy forceps can be reduced by applying air suction while removing the forceps. This simple method may reduce transmission of infectious agents during gastrointestinal endoscopies.


  • 1 Moore W E, Holdeman L V. Human fecal flora: the normal flora of 20 Japanese-Hawaiians.  Appl Microbiol. 1974;  27 961-979
  • 2 Stephen A M, Cummings J H. The microbial contribution to human faecal mass.  J Med Microbiol. 1980;  13 45-56
  • 3 Alfa M J, Sitter D L. In-hospital evaluation of orthophthalaldehyde as a high level disinfectant for flexible endoscopes.  J Hosp Infect. 1994;  26 15-26
  • 4 Kaczmarek R, McCrohan J, Reynolds C. et al . Multi-state investigation of the actual disinfection/sterilization of endoscopes in health care facilities.  Am J Med. 1992;  92 257-261
  • 5 Martin M, Reichelderfer M. APIC guidelines for infection prevention and control in flexible endoscopy.  Am J Infect Control. 1994;  22 19-38
  • 6 Rutala W. APIC guideline for selection and use of disinfectants.  Am J Infect Control. 1996;  24 313-342
  • 7 Schembre D B. Infectious complications associated with gastrointestinal endoscopy.  Gastrointest Endosc Clin N Am. 2000;  10 215-232
  • 8 Chu N S, McAlister D, Antonoplos P A. Natural bioburden levels detected on flexible gastrointestinal endoscopes after clinical use and manual cleaning.  Gastrointest Endosc. 1998;  48 137-142
  • 9 Heudorf U, Exner M. German guidelines for reprocessing endoscopes and endoscopic accessories: guideline compliance in Frankfurt/Main, Germany.  J Hosp Infect. 2006;  64 69-75
  • 10 Mehta A C, Minai O A. Infection control in the bronchoscopy suite. A review.  Clin Chest Med. 1999;  20 19-32
  • 11 Kinney T P, Kozarek R A, Raltz S. et al . Contamination of single-use biopsy forceps: a prospective in vitro analysis.  Gastrointest Endosc. 2002;  56 209-212
  • 12 Nesa D, Lortholary J, Bouakline A. et al . Comparative performance of impactor air samplers for quantification of fungal contamination.  J Hosp Inf. 2001;  47 149-155
  • 13 Engelhart S, Glasmacher A, Simon A. et al . Air sampling of Aspergillus fumigatus and other thermotolerant fungi: comparative performance of the Sartorius MD8 airport and the Merck MAS-100 portable bioaerosol sampler.  Int J Hyg Environ Health. 2007;  210 733-739
  • 14 Werner G, Coque T M, Hammerum A M. et al . Emergence and spread of vancomycin resistance among enterococci in Europe.  Euro Surveill. 2008;  13 pii:19 046
  • 15 Bronowicki J P, Vernard V, Botte C. et al . Patient-to-patient transmission of hepatitis C virus during colonoscopy.  N Engl J Med. 1997;  337 237-240
  • 16 Spach D H, Silverstein F E, Stamm W E. Transmission of infection by gastrointestinal endoscopy and bronchoscopy.  Ann Intern Med. 1993;  118 117-128
  • 17 Struelens M J, Rost F, Deplano A. et al . Pseudomonas aeruginosa and enterobacteriaceae bacteremia after biliary endoscopy: an outbreak investigation using DNA macrorestriction analysis.  Am J Med. 1993;  95 489-498
  • 18 Dwyer D M, Klein E G, Istre G R. et al . Salmonella newport infections transmitted by fiberoptic colonoscopy.  Gastrointest Endosc. 1987;  33 84-87
  • 19 Mandelstam P, Sugawa C, Silvis S E. et al . Complications associated with esophagogastroduodenoscopy and with esophageal dilation.  Gastrointest Endosc. 1976;  23 16-19
  • 20 Kimmey M B, Burnett D A, Carr-Locke D L. et al . Transmission of infection by gastrointestinal endoscopy.  Gastrointest Endosc. 1993;  36 885-888
  • 21 Cronmiller J R, Nelson D K, Salman G. et al . Antimicrobial efficacy of endoscopic disinfection procedures: a controlled, multifactorial investigation.  Gastrointest Endosc. 1999;  50 152-158
  • 22 Tuffnell P. Salmonella infections transmitted by a gastroscope.  Can J Public Health. 1976;  67 141-142
  • 23 Greene W H, Moody M, Hartley R. et al . Esophagoscopy as a source of Pseudomonas aeruginosa sepsis in patients with acute leukemia: the need for sterilization of endoscopes.  Gastroenterology. 1974;  67 912-919
  • 24 Elson C O, Hattori K, Blackstone M O. Polymicrobial sepsis following endoscopic retrograde cholangiopancreatography.  Gastroenterology. 1975;  69 507-510
  • 25 Graham D Y, Alpert L C, Smith J L. et al . Iatrogenic Campylobacter pylori infection is a cause of epidemic achlorhydria.  Am J Gastroenterol. 1988;  83 974-980
  • 26 Parker H W, Geenen J E, Bjork J T. et al . A prospective analysis of fever and bacteremia following ERCP.  Gastrointest Endosc. 1979;  25 102-103
  • 27 Gorse G J, Messner R L. Infection control practices in gastrointestinal endoscopy in the United States: a national survey.  Infect Control Hosp Epidemiol. 1991;  12 289-296
  • 28 Hautemanière A, Hunter P R, Diguio N. et al . A prospective study of the impact of colonization following hospital admission by glycopeptides-resistant enterococci on mortality during a hospital outbreak.  Am J Infect Control. 2009;  37 746-752
  • 29 Silvis S E, Nebel O, Rogers G. et al . Endoscopic complications: results of the 1974 American Society for Gastrointestinal Endoscopy survey.  JAMA. 1976;  235 928-930
  • 30 Corson S L, Block S, Mintz C. et al . Sterilization of laparoscopes: is soaking sufficient?.  J Reprod Med. 1979;  23 49-56
  • 31 Vennes J A. Infectious complications of gastrointestinal endoscopy.  Dig Dis Sci. 1981;  26 60S-64S
  • 32 Hanson P JV, Gor D, Jeffries D J. et al . Elimination of high titre HIV from fiberoptic endoscopes.  Gut. 1990;  31 657-660

1 The authors contributed equally.

S. R. VavrickaMD 

University Hospital Zurich
Division of Gastroenterology and Hepatology

Raemistrasse 100
CH-8091 Zurich

Fax: +41-44-2554503

Email: stephan.vavricka@usz.ch