Sometimes, although not dealing with colon, you have to perform a left side colectomy or sigmoidectomy followed by an end-colostomy. The most common reason is for colon ischemia. Here are some tips to follow.
How to start
First, you have to decide where will be the bottom of end of colon transection. This will definitely be at a relatively healthy area below th ischemic colon. The color of the colon is the best indicator of a viable colon. Additionally, you can cut with a pair of scissors the adjacent epiploic process and see if there is sparkling bleeding from the tiny arteries in it. If yes carry on and prepare for colon transection. If not, try at a bit lower level. Then, clean the area you have decided to divide by cutting all the epiploic processes and the omentum around it and pass a cotton tape around it. Finally, using a stapling device transect the colon.
Grapping the proximal part of the colon dissect close to it going upwards using a pair of scissors. Take care to carefully divide the feeding vessels of the colon with clamps particularly on the area of mesocolon. Follow, this until the total ischemic colon has been dissected. Special care should be taken in the mobilisation of the splenic flexure, if a typical left colectomy has to be done. In that case, mobilise the flexure “from within” the colon, meaning that you have to stay close to the colon and divide everything around, avoiding to divide everything from the spleen area.
After you have mobilised and dissected the total length of the ischemic colon, transect the colon on the proximal end with the same technique as on the distal end described previously. It is usually in the distal descending colon on a sigmoidectomy, or on the middle of transverse colon in an extended left colectomy.
Now it is time to prepare the remained colon for the end colostomy. The area of the colostomy should be at the left lower quadrant in case of a sigmoidectomy, or in the right upper quadrant in case of a left colectomy. Care should be taken to make the skin hole for the colostomy a good way apart the laparotomy incision and apart the proximal bony structure, either the left anterior upper iliac crest or the the right rib cage. First, identify a healthy area of the colon using as indicators its colour and the bleeding from the adjacent epiploic process. Then, clean this area, but by keeping intact the feeding mesocolon. Following, make a hole in the skin where you have decided to make the colostomy, using knife and diathermy. Mind to make as good hemostasis as possible, to avoid a postop hepatoma of the colostomy. The hole should be as large as to accommodate the first two of your fingers easily. Grab the colon with a Babcock forceps and pull it out of the abdomen through the hole. Stabilize the colon there, by using 2 isolated suture from the adjacent skin
After you have closed properly the abdomen, now it is the time to construct the end-colostomy. The end part of the colon should be diverted out. Here is how you do it. Using 2/0 or 3/0 absorbable sutures, secure the colostomy on the skin by using isolated sutures on the four ends of an imaginary cross. The trick is to put the suture first from the skin, then from the serumuscular tissue (heavy bite) and finally on the end of the colon by passing from the serumuscular tissue (heavy bite) to the mucosal tissue (small bite). Then, stabilise everything on the skin by tying down one across the other. Finally, put some other sutures one between the other two using the same fashion.