My dog is receiving intensive care in the hospital, and he’s not eating on his own. I realize that not eating is a bad thing, but why?
Hospitalization can have a profoundly negative impact on a dog's nutritional status. Hospitalized dogs can become malnourished due to decreased food intake, and this can lead to an immune system that doesn’t function well. Poor food intake also reduces the body’s ability to manage or repair damaged tissues, and the lack of nutrients can result in abnormal drug metabolism.
How can the immune system be affected by nutrition?
The immune system cannot funbection normally if the body does not receive appropriate amounts of food, or if nutrients aren’t adequately distributed. Depressed or decreased immune function can raise the risk for infection, which can lead to anorexia (the absence of any appetite), and this further compromises the immune system. Protein deficiency decreases the number of immune system cells circulating throughout the body and lowers their functional capacity. Thankfully, restoring adequate food intake can quickly improve immune system function.
What is the relationship between nutrition and tissue healing?
Wound healing and tissue repair are closely interrelated with nutrition. First, energy from nutrients is required for all the body's cells to function effectively. Energy is supplied in the diet by proteins, fats, and carbohydrates. Amino acids from dietary proteins, as well as carbohydrates, contribute to muscle and tendon repair. Rebuilding tissues following injury or surgery requires increased protein production that must be fueled by adequate nutritional intake.
How can nutrition influence medication metabolism?
All medications that enter the body must be distributed throughout the tissues, metabolized, and ultimately eliminated from the body for them to be effective. In a hospitalized, critically ill dog that’s not eating well, normal cellular metabolic activities are disrupted. This disruption can lead to problems with medications, resulting in either inadequate drug activity or a relative overdose if drug elimination is slowed.
What other negative effects are related to disrupted nutrition during hospitalization?
Malnutrition during hospitalization may contribute to a dog needing a longer stay and a prolonged recovery, resulting in a larger hospital bill. With partial anorexia (also called hyporexia), a sick dog eats some of their daily calories, but not enough to meet a calculated goal. With complete anorexia (a lack of interest in food prior to satisfying the body's calorie needs), a sick dog eats nothing. Anorexia during hospitalization may be caused by:
- disease
- inflammation
- cancer
- pain
- fear
- anxiety
- emotional distress
Dogs recovering from illness, surgery, or an injury are often in a hyper-metabolic state in which the body's nutritional needs exceed normal baseline requirements. A hospitalized dog experiencing partial anorexia for three days, or complete anorexia for 48 hours, is a candidate for nutritional intervention.
"A hospitalized dog experiencing partial anorexia for three days, or complete anorexia for 48 hours, is a candidate for nutritional intervention."
Whenever possible, we want to use the gastrointestinal (GI) system for nutrient delivery rather than intravenous support (also called parenteral feeding). Nutritional interventions that use the GI tract may be as simple as placing food in the mouth to stimulate the swallowing reflex, or as complex as surgically placing a feeding tube into the stomach or small intestine.
What methods are used to feed a critically ill or hospitalized dog who won’t eat on his own?
Oral feeding is a passive procedure, which means the sick dog should never be forced to eat or swallow food. The dog should be standing or sitting upright (not lying down) for any attempt at oral feeding. Placing a small ball of canned food in the mouth may be enough to stimulate the swallow reflex, appetite, and eating. Alternatively, a large-tipped syringe may be used to deliver a small amount of liquid or semi-solid slurry into the mouth. Stop any oral feeding attempts if the dog refuses to swallow the food, as there is a risk that the food will go into the airway, resulting in aspiration pneumonia.
Feeding Tubes allow for delivery of nutrition support and can mean the difference between life and death. There are many types of feeding tubes available for delivering appropriate nutrients to sick dogs. For one or two days of tube feeding, your veterinarian may choose a simple orogastric (mouth-to-stomach) tube. Anesthesia is not required to slip the tube down the esophagus, deliver the meal via syringe, and then pull the tube out. This method is well tolerated, but can only be used for a day or two. When a sick dog needs support for a longer period of time, choosing a tube that can stay in place allows for better, safer delivery of food.
- Nasoesophageal (NE) or Nasogastric (NG) tube. The NE tube is placed in one nostril, down into the esophagus near the opening of the stomach. NG tubes are placed into one nostril and all the way down the esophagus and into the stomach. This tube type is designed to be very narrow and only liquid diets should be used. If a canned gruel or slurry is used, it will likely clog the tube. Anesthesia is not required to place an NE/NG tube in critically ill dogs. These tubes are used only while the dog is in the hospital and can be used for 1–10 days.
- Esophagostomy (E-) or gastrostomy (G-) tubes. For some sick dogs, it is best to avoid the mouth and throat and deliver food directly into the stomach. These tubes are placed using a short-acting general anesthetic and the procedure is relatively brief. The esophagostomy tube enters the side of the neck and ends in the esophagus, near the opening to the stomach. It is sutured in place and can be used for weeks to months. A gastrostomy tube can stay in place for months to years. Home care of these tubes is generally quite easy.
How do I feed my dog using a tube?
Your veterinarian will develop a feeding plan with a nutrient profile of the food that’s specific to your dog’s nutrient needs and the size of the feeding tube. A member of the health care team, usually a trained veterinary technician, will teach you how to do the feedings at home as well as how to clean the tube site.
"A member of the health care team, usually a trained veterinary technician, will teach you how to do the feedings at home as well as how to clean the tube site."
Feeding schedules usually require multiple small meals every few hours over the course of the day. Your veterinarian will provide a total volume for each day, as well as instructions for flushing the tube with water before and after a feeding. Flushing with water is important to make sure the tube doesn’t get clogged. The selected diet your veterinarian chooses may be a canned dog food, a liquid diet, or even kibble. Canned or kibble diets need to be combined with water and processed in a blender before feeding. Liquid diets can be delivered straight from the bottle. Some veterinarians consult with a veterinary nutritionist for help choosing the best diet for their patient.
How long will my dog need a feeding tube?
Each critically ill dog has its own period of convalescence; sometimes as short as 3–5 days, or as long as 2–3 months. Your veterinarian will work with you to decide how long a feeding tube is needed. Once your dog has been home several days and you’ve gotten used to doing the tube feedings, your pet will eventually show you if it’s interested in eating food by mouth. Don’t try to rush things, though! Talk with your veterinarian about when, how much, and how often to offer food that your dog can eat by mouth. Dogs with feeding tubes can drink water and eat on their own with the tube in place.
As your dog eats more on its own, you will need to keep a food diary so you can document the amount of food your dog eats and add that to the amount being delivered through the feeding tube. Your veterinarian will guide you on how and when to decrease tube feedings proportionately. Once a dog is eating adequately on their own, the feeding tube can be removed by your veterinarian. This procedure is usually done without anesthesia or sedation.
With good planning and early intervention, critically ill dogs can be spared the detrimental effects of malnutrition during hospitalization and healing.
