Colonoscope length and procedure efficiency.

We reviewed 195 colonoscopies to determine whether procedure efficiency differed with the use of an intermediate-length (135 cm) colonoscope compared with a long (165 cm) colonoscope. The cecum was intubated with the 135-cm scope in 92.6% of procedures and with the 165-cm colonoscope in 96.8% of procedures (chi 2 method, p = 0.26). The mean procedure duration was 36.7 min for 107 complete procedures performed with the 135-cm colonoscope and 48.4 min for 55 examinations using the 165-cm colonoscope (t test, p < 0.001). Colonoscopy with the 135-cm instrument required mean meperidine and midazolam doses of 59.9 mg and 1.8 mg, respectively, compared with doses of 69.1 mg and 2.0 mg, respectively, with the 165-cm colonoscope. The differences were not significant. Although the cecal intubation rate is slightly less for the 135-cm colonoscope, insertion takes significantly less time and is probably more comfortable for the patient than with the 165-cm colonoscope.