Colonic motility distal to a deviating ileostomy after rectal resection and construction of a primary anastomosis

No consensus exists on the necessity of mechanical bowel preparation (MBP) for
patients undergoing rectal surgery with construction of a primary anastomosis
and a deviating ileostomy. For a long time, the hypothesis was that the use of
MBP reduced possible dangerous complications due to anastomotic leakage.
However, recent studies show no increase in complications when MBP is replaced
by a preoperative enema. These results are of great clinical importance since
the use of MBP is not harmless and could lead to several complications, which
are not reported for an enema.
It is thought that colon transition time (CTT) is severely decreased or even
halted in the early postoperative phase after rectal resection, anastomosis and
construction of a protecting ileostomy. This could explain the similar
complication rates following the two different bowel preparation strategies,
since without colon motility, stool would never be able to pass the new
anastomosis and cause complications when an anastomotic leakage is present. It
is hypothesised that the decreased motility is the result of the operation
itself and independent of the type of bowel preparation, which is underlined by
the fact that complication rates are similar. However, so far CTT in rectal
surgery has only been studied in patients that received full MBP and no studies
are available for patients receiving an enema only.

The primary aim is to study colon motility following rectal resection with the
construction of a deviating ileostomy in patients that received an enema as
bowel preparation. We hypothesise that CTT is halted or decreased, similar as
in patients that received full MBP. We will compare our results with the
current literature on colon motility after preparation using MBP and determine
whether colon motility is dependent on the type of bowel preparation given. The
eventual goal is to determine whether MBP is indeed necessary or that it is
redundant and we could suffice with an enema.

Prospective cohort study

All patients included in this study will have 24 colonic radiopaque markers
placed in their cecum during the operation to observe colonic motility. These
markers have been used as a diagnostic tool for slow-transit colon for several
decades and are regarded as a safe and minimally invasive procedure. in time,
the body will self excrete these markers with the feces and no additional
interventions are needed to remove them from the bowel.
Movement of these markers in the colon will be monitored using abdominal X-rays
(AXR) on postoperative days 1, 3, 5 and 7. These extra AXRs lead to a small
additional radiation dose. However, in consultation of an independent
radiologist this can be considered negligible, especially since only patients
aged 50 years or older will be included. All other perioperative procedures
will be conducted in accordance with standard protocol.
The potential benefits of participation in this study is a potential final
answer to the much debated discussion about the optimal preoperative bowel
preparation before rectal resection and the construction of a primary
anastomosis and deviating ileostomy.