Effect of a proprietary intraluminal stiffening wire device on cecal intubation time and rate with used colonoscopes; a randomized, controlled trial

Jeffrey M East, Jeffrey M East

Abstract

Background: Colonoscopes are designed with balance between flexibility, required to negotiate angulations, and stiffness, required to counteract the propensity for looping in unfixed sections of the colon, which retards advancement of the instrument. Colonoscopy can be challenging with old instruments that have lost native stiffness and become less responsive to torquing.A new intraluminal stiffening device has become available in two grades of stiffness. However, there is no published evidence of its effectiveness. This randomized, controlled trial was designed to determine the effectiveness of the stiffening wires in improving cecal intubation rate and time following routine application. A secondary analysis determines effectiveness of application only after intractable failure with the unaided colonoscope.

Methods: The colonoscope tested was an Olympus CF-100TL, approximately fifteen years old. Patients were randomly assigned to the unaided colonoscope or the standard or firm wire introduced routinely on entry into transverse colon. Each phase of colonoscopy was timed. Failure to advance the colonoscope for 5 minutes (despite usual manipulations to minimize looping) required switching to another intervention according to a prescribed methodology and the originally assigned intervention was recorded as failed.

Results: The study was terminated after accrual of 112 participants (target sample size 480) because the colonoscope required repairs (no damage attributable to stiffening wires) which would have been uneconomical. There were no statistically significant differences between per-protocol cecal intubation rates (81.1, 71.1 and 70.3 percent respectively), a finding which persisted after multiple imputation for a virtual sample size of 480. Similarly, there were no statistically significant differences between per-protocol cecal intubation times (15, 16.2 and 13.9 minutes). However, a statistically significant improvement in cecal intubation rate (from 81.1% to 97.3%, P = 0.0313) was achieved when the wires were applied after intractable failure of the unaided colonoscope in the first intervention group.

Conclusions: Routine application of either stiffening wire does not improve caecal intubation rate nor time compared to the unaided colonoscope. However, application of the stiffening wires after intractable failure of the unaided colonoscope enabled a statistically significant improvement in cecal intubation rate.

Trial registration: clinicaltrials.gov Identifier: NCT01115010.

References

    1. Ginsberg GG. Colonoscopy with the variable stiffness colonoscope. Gastrointest Endosc. 2003;58:579–584. doi: 10.1067/S0016-5107(03)01873-X.
    1. Baron TH. The variable stiffness colonoscope: a scope for all seasons? Am J Gastroenterol. 2002;97:2942–2943. doi: 10.1111/j.1572-0241.2002.07091.x.
    1. Shah SG, Saunders BP. Aids to insertion: magnetic imaging, variable stiffness, and overtubes. Gastrointest Endosc Clin N Am. 2005;15:673–686. doi: 10.1016/j.giec.2005.08.011.
    1. Sullivan MJ. Variable stiffening device for colonoscopy. Gastrointest Endosc. 1990;36:642–643. doi: 10.1016/S0016-5107(90)71208-4.
    1. Sivak MV. Gastroenterologic Endoscopy. Saunders, W.B; 1999.
    1. Ruffolo TA, Lehman GA, Rex D. Colonoscope damage from internal straightener use. Gastrointest Endosc. 1991;37:107–108.
    1. Zutron Medical. Colonoscope stiffening device. 2009. .
    1. Lee SK, Kim TI, Shin SJ, Kim BC, Kim WH. Impact of prior abdominal or pelvic surgery on colonoscopy outcomes. J Clin Gastroenterol. 2006;40:711–716. doi: 10.1097/00004836-200609000-00010.
    1. Dupont WD, Plummer WD Jr. Power and sample size calculations. A review and computer program. Control Clin Trials. 1990;11:116–128. doi: 10.1016/0197-2456(90)90005-M.
    1. Fisher RA, Yates F. In: Field Trials of Health Interventions in Developing Countries: A Toolbox. 2. Smith PG, Morrow RH, editor. Macmillan Education, London; 1996. Appendix 7.1; pp. 145–148.
    1. East JM. Data from stiffening wire and colonoscopy study. LabArchives. 2012. .
    1. Anderson JC, Messina CR, Cohn W, Gottfried E, Ingber S, Bernstein G, Coman E, Polito J. Factors predictive of difficult colonoscopy. Gastrointest Endosc. 2001;54:558–562. doi: 10.1067/mge.2001.118950.
    1. Takahashi Y, Tanaka H, Kinjo M, Sakumoto K. Prospective evaluation of factors predicting difficulty and pain during sedation-free colonoscopy. Dis Colon Rectum. 2005;48:1295–1300. doi: 10.1007/s10350-004-0940-1.
    1. Betensky RA. Multiple imputation for early stopping of a complex clinical trial. Biometrics. 1998;54:229–242. doi: 10.2307/2534010.
    1. Odori T, Goto H, Arisawa T, Niwa Y, Ohmiya N, Hayakawa T. Clinical results and development of variable-stiffness video colonoscopes. Endoscopy. 2001;33:65–69. doi: 10.1055/s-2001-11174.
    1. Othman MO, Bradley AG, Choudhary A, Hoffman RM, Roy PK. Variable stiffness colonoscope versus regular adult colonoscope: meta-analysis of randomized controlled trials. Endoscopy. 2009;41:17–24. doi: 10.1055/s-0028-1103488.
    1. Hsieh YH, Zhou AL, Lin HJ. Comparing different methods of activating the variable stiffness function of a pediatric variable stiffness colonoscope. J Chin Med Assoc. 2008;71:23–29. doi: 10.1016/S1726-4901(08)70068-6.

Source: PubMed

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