Endoscopy 2005; 37(5): 415-417
DOI: 10.1055/s-2005-861197
Original Article
© Georg Thieme Verlag KG Stuttgart · New York

Assessing the Adequacy of Endoscopically Tied Knots: A Functional Approach

B.  Hu1 , L.  C.  L.  Sun1 , M.  Karmakar2 , P.  B.  Cotton3 , C.  J.  Gostout3 , R.  H.  Hawes3 , A.  N.  Kalloo3 , S.  V.  Kantsevoy3 , P.  J.  Pasricha3 , S.  C.  S.  Chung1, 3
  • 1Endoscopy Center, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
  • 2Department of Anesthesia and Intensive Care; Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
  • 3The Apollo Group
Further Information

Publication History

Submitted 7 October 2004

Accepted after Revision 16 November 2004

Publication Date:
20 April 2005 (online)

Background and Study Aims: Endoscopic intracorporeal knots have potentially enormous applications in endoscopic surgery. We describe a method for testing the security of various types of endoscopically tied knots using a vessel perfusion manometer system.
Methods: A 4-cm segment of porcine splenic artery was placed on the mucosal surface of a pig stomach. The two ends of the vessel were brought out through the gastric wall and connected to a two-way manometer. One end was also joined to a pressure infusion bag. The stomach was mounted in an Erlangen training model. A long 3/0 nylon thread, previously introduced into the submucosal layer of the stomach and encircling the vessel, was brought out from the mouth. Three-throw square knots, Mayo knots, “surgeon’s” knots and five-throw square knots were tied and pushed into place using a cap attached to a gastroscope. The pressure at the two ends of the artery was compared. If the pressure could be increased to over 200 mm Hg at one end without a change in the other, the knot was considered secure.
Results: Each type of knot was tested 12 times under endoscopic vision. The range for mean knotting time was 3.4 - 4.5 minutes. Five-throw knots took significantly longer to tie than three-throw knots (P < 0.005). There was one loose knot in each of the three-throw and Mayo groups, and three each in the “surgeon’s” and five-throw groups (P > 0.05).
Conclusions: This system is a reliable model for testing intracorporeal knots tied endoscopically. A three-half-hitches square knot with 3/0 nylon, tied using a flexible endoscope and knot-tightening cap, can withstand pressure up to 200 mm Hg.

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S. C. S. Chung, M. D.

Endoscopy Center, Prince of Wales Hospital, The Chinese University of Hong Kong ·

Shatin N.T. · Hong Kong SAR · China

Fax: +852-2635-0075

Email: sydneychung@cuhk.edu.hk