Review for 10.1186/1471-230X-10-123 (2010)

Reviewer's report
Title:Maximizing the general success of cecal intubation during propofol
sedation in a multi-endoscopist academic centre
Version: 1Date:15 August 2010
Reviewer: franco radaelli
Reviewer's report:
The authors presents their own experience with the use of propofol sedation for
routine colonoscopy practice. The study was carried out in a large university
hospital over a 12 months study period, and twenty-one endoscopists of different
level of expertise participated.
Major compulsory revisions:
1. In the background of the study, the authors hypothesized that deep sedation
with propofol could enhance the cecal intubation rate. In the conclusion, they
stated that “with routine deep sedation the completion rate nears the target
performance for screening programs”(cecal intubation rate > 95%). Finally, in the
discussion, they speculated that that the routine use of propofol led to a
substantial improvement in the performance, as the cecal intubation rate was
significantly higher than that reported in a recent nationwide study. Unfortunately,
the study design cannot substantiate these statements, due to the absence of a
control group of patients undergoing colonoscopy without deep sedation, As
consequence, the authors cannot demonstrate the role of deep sedation in
improving the quality of colonoscopy. At this regard, the results from the recently
published Italian survey cannot be used as term of comparison. Indeed, in this
survey the overall cecal intubation rate was about 85%, but about 20% of the
three-hundred centers involved in the study reported reaching the cecum in 90%
or more of examinations. It would be interesting to know the cecal intubation rate
of the authors’ centre reported in the Italian survey, to get an idea whether
propofol sedation did really lead to an improvement of colonoscopy performance.
2. During the 12 months study period, 1381 consecutive colonoscopies with
propofol sedation were performed by twenty-one endoscopists. These
colonoscopy volume seems to be too small for a large university centre, and it is
likely that a large amount of procedures were performed without deep sedation
(i.e., standard sedation and analgesia or unsedated procedures). The authors
should specify the overall number of colonoscopies performed in the study
period, and the reasons for allocating colonoscopy patients to deep selection.
Indeed, the selection of patients to deep sedation (selection bias) may identify a
subgroup of patients in which cecal intubation might be more difficult.
Discretionary revisions:
1. Among 21 endoscopists, only three of them were gastroenterologists. Many
studies focusing on colonoscopy performance (i.e., Shah HA, Gastroenterology
2007; 132: 2297-303) identified better performance for gastroenterologists than
surgeons. Did you observe the same?
2. Colonoscopy interrupted for organic stenosis should be considered as a
failure. Indeed, a diverticular stenosis could be handled by an experienced
endoscopist but not by a less skilled one. However, the authors should be
specified the number of procedures interrupted due to stenoses.
3. Please, specify the initial induction dose.
4. As safety issue of propofol sedation are of paramount importance, please
provide more details on the two allergic reactions and the respiratory events. The
authors stated that no hemodynamic resuscitation was needed. Did any patients
required mask ventilation or intubation?
Level of interest: An article of limited interest
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
'I declare that I have no competing interests'