Colostomy/Ileostomy

30-50% of all stomas will become permanent
An ileostomy is better than a transverse colostomy (should be avoided at all costs)

End Colostomy
Where possible pre-op marking by stomal therapist
Be aware of belt lines, skin creases
Draw triangle between ASIS and umbilicus
Stoma should be slightly above centre of triangle, through rectus abdominus muscle.
If obese, multiple lower abdominal scars or cord injury, site above umbilicus

Dissect colon sufficient to bring 3-4cm of colon above skin (further dissection will lead to prolapse)
May need to divide IMA and mobilise splenic flexure for extra mobility
IMA division should be proximal to left colic to preserve flow through proximal arcades

Kocher/Allis on fascia and skin to ensure stoma takes direct route through abdominal wall
Cut skin disc with Kocher and eye of artery forcep
Linear cut through abdominal fat and anterior sheath 2-3cm and blunt dissection through rectus
Pack under abdominal wall and incise posterior sheath. 2 finger size hole.
Babcock on colon and bring through abdominal wall. Ensure bowel is not twisted.
Close midline incision

Four everting sutures in north, south, east, west position, incorporating dermis, then seromuscular layer 3-4cm from end, then full thickness through terminal end of bowel. Tie after placing all four. Complete with one or two sutures between each.

The obese patient
Consider whether primary anastomosis is better than a difficult stoma
Principles are:
Resect all inflamed tissue
Mobilise splenic flexure
May need to transect IMA
May need to widen trephine
If impossible then can create 'pseudoloop' with a more proximal segment of bowel, using antimesenteric border of bowel (see figure above)

Construction of an 'end loop' colostomy may obviate need for formal laparotomy for closure (distal end as mucous fistula)

An endoscopic assisted stoma can be created obviating need for laparotomy. It is important to ensure correct end has been brought out by insufflating air into distal limb with colonoscope.