Feeding tubes in small animal practice (Proceedings)
Nutritional support is required for anorexic patients, debilitated patients, patients in a high catabolic stage (peritonitis, sepsis, burns), or stressed patients (surgical patient). Nutritional support allows a faster soft tissue healing, a better immune system response and a faster recovery from the patient. Nutritional support can be performed with food intake stimulation, force feeding, and feeding tubes. Vitamin B, valium (0.2 mg/kg IV) and ciproheptadine (2 mg/cat 2 to 3 times a day) have been used to stimulate food intake in dogs and cats with variable results. Force feeding with a syringe or tube is possible for one day or two. Force feeding places lot of stress on the animal and may induce aspiration pneumonia. Feeding tube placed either surgically or under endoscopy is the most efficient technique to provide nutritional support to a patient. Feeding tubes can be easily placed at the end of an abdominal surgery and may avoid lot of complications and troubles after surgery. Gastrostomy and jejunostomy tubes are the 2 most commonly used feeding tube in small animal. Esophagostomy tube and gastrojejunostomy tube are the feeding tubes used most commonly.
A nasogastric tube can be placed in dogs and cats if feedings need to be continued for more than 2 days. It is a good technique for the nutritional support of young animals. It does not require general anesthesia for its placement. A topical anesthetic (bupivacaine: 2 to 5 drops) is placed into the nostril. Before placing the tube, the distance from the nares to the stomach needs to be measured. The stomach is located at the level of the last rib. A 3.5 French tube is recommended for puppies and kitten, while a 5.0 Fr tube can be used for adult cat and dogs less than 8 kg. With the animal's head held in a normal static position the tube is introduced in the nose in a caudo-medial direction ventral to the alar fold. Pushing the nose upward helps moving the tube downward in the ventral meatus. A stylet or guide wire might be useful to guide the tube in the correct direction. The tube progress through the larynx into the esophagus and the stomach. If the animal is coughing, the tube is more likely going into the trachea. A bolus of sterile saline ca be injected in the tube. If the animal coughs more likely the tube is in the trachea. If there is any doubts on the placement of the tube radiographs should be taken to confirm the placement of the tube in the stomach and not the trachea. Palpation of the trachea and the tube in the esophagus is a good indication for correct placement of the nasogastric tube. Since the tubes are small in diameter a liquid diet (Clinicare) is recommended. The tube needs to be flushed between feeding to prevent the tube from plugging.Esophagostomy tube
Several techniques have been described for placement of an esophagostomy tube placement in dogs and cats. The animal needs to be under general anesthesia. The entire left cervical region from the ventral to dorsal midline need to be clipped and prepared for surgery.
The left side of the cervical region is draped and a percutaneous feeding tube applicator (ELD Gastrostomy tube applicator) is inserted through the mouth in the proximal cervical esophagus. The tip of the ELD device is turned outward and the cervical tissue are tented up. A small skin incision is made just large enough to accommodate the feeding tube. The incision is made deeper to the esophagus and the sharp needle in the ELD is advanced to puncture through the esophagus. A feeding tube is attached to the needle. The needle is retrieved in the ELD device. The ELD device is retrieved through the mouth with the feeding attached. Now the feeding tube is going through the skin of the left cervical area, the esophagus, and exiting in the mouth. The tip of the tube is then redirected into the pharynx and the esophagus. The tube needs to be manipulated gently to prevent perforation of the distal esophagus. The tube is then secured with a Chinese finger trap suture. A light bandage is applied to protect the tube. The tip of the tube should be in the esophagus. It is then necessary to measure the length of the tube that could be placed in the esophagus without entering the lower esophageal sphincter. The lower esophageal sphincter is located at the level of the xyphoid. A large red rubber feeding tube can be placed with this technique. For a cat a 12 to 14 Fr tube can be placed and for a 30 kg dog a 20 Fr tube be used. It is recommended to increase the diameter of the hole at the tip of the tube to prevent obstruction of the tube with food.
An alternative technique is to use a large Carmalt or curve forceps for the placement of the tube instead of the ELD device. Forceps have a tendency to create a hole too large in the esophagus, which may result in leakage of saliva and food around the tube. It will induce a severe cellulitis, and abscess formation.
Blenderized food can than be used for the nutritional support of the patient. The animal is usually fed 4 times a day. The tube needs to be flushed after each feeding with copious amount of water. Tubes entering the stomach will induce vomiting. Some dogs or cats have been vomiting their tube.