Effectiveness of Stiffening Wire in Colonoscopy With Pre-Owned Colonoscopes

Overview

The study aims to determine whether a proprietary, FDA approved stiffening wire improves the efficiency of colonoscopy (that is, decreases the duration of the procedure) and/or enables complete visualization of the colon in a greater proportion of cases (than when the procedure is performed without it) with old, used colonoscopes. Colonoscopes are designed with a delicate balance between stiffness and flexibility. Stiffness helps to prevent curling (looping) of the colonoscope in those sections of the colon that are not fixed to the wall of the abdominal cavity and flexibility enables successful negotiation of bends or flexures in the colon. As colonoscopes age, they lose stiffness and this makes it very challenging to advance the colonoscope all the way to the cecum (the upper end of the colon). Even when the cecum is successfully reached, it may take an inordinately long time. In Jamaica, most endoscopists (General Surgeons and Gastroenterologists) use older, pre-owned colonoscopes imported from the USA, because the average patient and local health insurance companies cannot bear the level of fees that would enable cost recovery for new equipment. The stiffening wires (in two grades of stiffness) used in this study are passed through the biopsy channel of the colonoscope only after its tip has passed the upper end of the descending colon and entered the transverse colon. The device is safe when used as recommended by the manufacturers (and approved by the FDA), and does not appear to increase risk over and above the risk of colonoscopy with the unassisted colonoscope. Although the device clearly improves the stiffness of the colonoscope, there is no research evidence that it actually works in practice, either to improve cecal intubation rate or to decrease procedure time. It is therefore also unclear whether the possible benefit of using the device is achieved if introduced at the first opportunity allowed by the manufacturers or only after difficulty is encountered with the unassisted colonoscope. In this study, patients are randomly assigned to one of 3 "interventions". One group has colonoscopy performed with the colonoscope alone and the wires are only introduced if there is difficulty advancing the colonoscope after it has passed into the transverse colon ("difficulty" defined as failure to advance the tip of the colonoscope after 5 minutes). In the 2nd and 3rd groups, the assigned wire will be introduced as soon as the colonoscope enters the transverse colon and is removed if "difficulty" is encountered, as defined above. The different phases of colonoscopy will be timed with a stop watch and when a sufficient number of patients has been accrued, the investigator will be able to compare the time it takes to complete the procedure with and without the wires as well as the proportion of cases in which the cecum was reached with and without the assistance of the wires.