Percutaneous placement of a gastrostomy tube (Proceedings)
There are three methods available for placement of a gastrostomy tube: percutaneous nonendoscopic, percutaneous endoscopic, and surgical. Percutaneous placement methods rely on some device to carry a piece of suture from the lateral body wall out through the mouth. The two most widely used devices for percutaneous nonendoscopic placement are the Eld gastrostomy tube applicator and the Cook insertion device. These instruments have made the use of gastrostomy feeding tubes feasible in almost any practice. An overview of placement using the Eld device is given here.
Gastrostomy tubes are used in patients that require a feeding method that by-passes the pharynx and esophagus. They may also be used instead of an esophagostomy tube if long-term feeding (weeks to months) is anticipated; operator experience may decide which tube placement site is selected. Anesthesia is required for gastrostomy tube placement; selection of type of anesthesia is based on the patient's underlying disease. It is strongly recommended to protect the airway by endotracheal intubation even if not required for anesthetic delivery.Contraindications
A specific contraindication to the nonendoscopic percutaneous placement of a gastrostomy tube is existing esophageal damage, or stricture, that may predispose to esophageal perforation during passage of the placement applicator. Animals with megaesophagus should be fed below the pylorus to lessen the risk of aspiration pneumonia. In some patients with esophageal motility disorders, however, this risk is accepted over the risks and costs involved in surgical placement of an enterostomy tube. Gastrostomy tubes are not recommended for animals that have frequent vomiting due to causes such as primary gastric disease, gastric outflow obstruction, or gastric paresis. Two other relative contraindications to gastrostomy tube placement are immunosuppression and clinically evident ascites. Problems with dehiscence at the tube exit site and subsequent peritonitis have been encountered in FeLV positive cats.
Materials Needed for Placement
Several minutes can be saved during tube insertion by preparing the tube and connecting it to the Eld applicator prior to anesthetizing the dog or cat. Cut off the flared end of the tube and discard. Cut two 2-cm pieces of tubing off the tube at the cut end; these will serve as internal and external flanges. Using a No. 11 scalpel blade, make a stab incision through the center of each flange. Connect one to the tube by sliding it down onto the tube until it rests up against the mushroom tip (this forms the inner flange). The "button" end of the mushroom tip may be cut off to facilitate food delivery. Using an indelible marker, make 1-cm markings on the tube, starting at the internal flange. The tube is now assembled and ready to connect to the Eld applicator.
Tie the end of one piece of fishing line to the hole in the trocar of the Eld applicator and cut the end short. Thread the pipette tip, narrow end first, onto the free end of the fishing line. Next, attach the free end of the fishing line to the proximal end of the mushroom-tip tube, using a 20 gauge needle to pass the line through the tube. Pull the pipette tip firmly down onto the tube so that it will act as a guide for the end of the tube.
Loop the second length of fishing line through the eyelets of the mushroom tip and clamp the two ends together with a hemostat. If any difficulty is encountered during tube placement, traction on this safety loop will extract the tube.