Trial Information

Circular vs Cruciate Incision in the Abdominal Wall Fascia for coloStomy Construction - A Randomised Trial

Colostomy formation has been a standard surgical procedure for more than 100 years.
Initially the quality of life for stoma patients was all but good, as the appliances to
collect the feaces were cumbersome, smelly and did not ensure non-leakage. As late as in the
60-ies bandages were still primitive(1). Gradually these problems have decreased as
techniques for bandages have improved. A well functioning colostomy may in itself not
negatively affect the patient's Quality of Life (QoL)(2), although thorough information and
support from stoma care nurses is of utmost importance (3). However, this can only be said
if the stoma is well functioning and if the complications are kept to a minimum. The
complication rate after stoma formation is still considerable, with figures of 21-70% (4, 5)
and studies have shown that adequate height; type of stoma, BMI, emergency surgery and
gender may be of importance in reducing the risk of complications both in the short and
long-term (6-8).

The surgical technique of stoma formation is only partly evidence based. There are few
studies directed at technical details about stoma construction and their future impact on
stoma function, apart from the importance of the stoma height (6). One study has tested to
standardize the skin incision to 2/3rds of the width of the bowel (9), although the actual
impact of this on the functional outcome of the stoma was not presented.. In the surgical
literature a cruciate incision in the fascia and extraction of the bowel through a hole
sufficient in size is a short description of the surgical technique (10). In clinical
practice sufficient size of the hole has often been equal to "two fingers-width", is
commonly used, which refers to the width of the surgeon's fingers, a fairly inexact
measurement. A pilot study from Sahlgrenska University Hospital has found that this clinical
practice for the most part results in a skin incision diameter of 50% of the bowel width.

There have been discussions regarding the placement of the stoma and effects on hernia
incidence, whether in the obliquous muscle or the rectus abdominis (11) or if the bowel
should take an extraperitoneal route (ad modum Goligher) or not (12). No studies have been
sufficient in design or size to thoroughly answer the question.

Parastomal hernia is a long-term complication that is common, in the literature figures up
to almost 50% have been reported (13, 14). Attempts to reduce the rates of parastomal
hernias have been made in the last few years with a placement of a mesh, at the construction
of the stoma, (15-19). This practice has not been universally accepted, in part due to a
hesitance in the surgical society because of the risk of infections with foreign body
material, and partly due to that most studies are underpowered for their main outcome
variable. Another suggestion for the basic construction of the stoma has been to make a
circular incision in the fascia instead of a cruciate, but this has not been documented in
any studies. It has been described in conjunction with use of circular stapling devices in
the skin, no hernias were found, however the patient numbers were small (20). It is apparent
that further studies are most welcome.

The evaluation of parastomal hernias has been discussed. Janes et al. used clinical
examination in their studies (16, 17), and confirmed in a later study that the concurrence
with a CT-verified parastomal hernia was (21) sufficient if performed in a prone position.
Another recent study found that results from a CT-scan was not correlated with patient
symptoms (22). Other studies have evaluated the use of ultrasound and found it feasible
(23). The conclusion must be that evaluation of parastomal hernias may be difficult and must
be standardized in a study.

The hypothesis to be tested in this study is that a circular incision in the abdominal wall
fascia with a diameter of 50% of the width of the patients left colon results carries less
risk of parastomal hernaition than a cruciate incision where the each of the arms measure
1/2 of the diameter of the patients left colon.

The aim of this trial is to compare the parastomal hernia formation within 12 months after
stoma surgery between circular and cruciate incision.