INTRODUCTION: Few other surgical procedures adversely affect a patient’s quality of life as much as a poorly functioning stoma. An ideal stoma meets two criteria: (1) The site is optimally matched to a patient’s variability in body form, physical ability and activities. (2) The construction minimises complications that relate to the use of stomal appliances and minimises technical failings such as parastomal hernia or prolapse.
1.The Skin and Subcutaneous Incision
A circular stomal opening is generally preferred, though for temporary stomata a linear incision minimises skin loss and may improve cosmesis after closure. We favour making a cruciate incision with cutting electrocautery, each quadrant being excised in a curved fashion with electrocautery or curved (Mayo) scissors to prevent charring.
A cruciate incision of the muscle fascia is generally used, mirroring that for the skin incision but without excision. It is common practice during laparotomy to align the muscle fasciotomy and skin incision by medial retraction of the rectus sheath using tissue-grasping forceps (e.g. Lanes’). This may reduce angulation of the bowel through the abdominal wall, though is unlikely to affect the duration of paralytic ileus in the post-operative phase and has little effect on eventual function.
A muscle-splitting incision through rectus abdominis is advocated, though this may simply be a necessary anatomical consequence reflecting the preference for an anterior stoma distant from the umbilicus, iliac crest and midline wounds. Stomal formation lateral to rectus abdominis does not actually seem to increase the risk of para-stomal hernia formation. This is unsurprising, since muscle division and correct closure at apppendicectomy rarely leads to hernia formation.
4.Choice of Bowel for the Construction of a Stoma
The principles of good anastamotic healing apply equally to stomal construction. Attention to tissue handling, vascularity and lack of tension encourage primary healing at the muco-cutaneous junction. Poor technique risks separation of the muco-cutaneous junction and prolonged healing by granulation, leading to stenosis. Tension may worsen stomal or spout retraction and can lead to difficulties in attaching stomal appliances to a concave stoma, particularly if a tight limb of the stoma gives a skin fold crease. Similarly, impaired vascularity can turn stomata a worrying colour, particularly if inotropes are required for a critically ill patient, and although frank necrosis is rare, stenosis may result in the longer term.
“Patients often judge a surgeon’s technical ability by the external
appearance of scars, and may also judge a surgeon’s care and precision
by the appearance and function of an abdominal stoma.”