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Critically Ill Patients-Developing a Nutritional Plan


Part 1

Have you ever asked yourself: “Do I provide a robust nutritional plan for my critically ill patients?” Do you even consider nutrition to be an important factor during this time?

In a referral clinic study of 276 dogs hospitalised for multiple days, patients achieved a daily positive-energy balance (>95% Resting Energy Requirements, or RER) on only 220 of the 821 (27%) full “dog-days”.[1]  Dogs who received less than a third of their energy requirement were likely to have a negative outcome, with increased morbidity and mortality. I regularly ask this question when I am out visiting clinics, specialty hospitals and the University, and you would be surprised how few clinics consider the nutrition of critically ill patients.

Why is nutrition important?

Poor critical care nutrition can result in:

  • Dysfunctional healing
  • Suppressed immune function
  • Cachexia
  • Increased morbidity and mortality
veterinarian with a dog

While it may appear that patients resting in a cage require little or no nutrition, their needs are in fact significant – hospitalised patients are likely to be deficient in both protein and calories due to a decrease in total food intake. Therefore, regularly assessing the nutritional requirements of a critically ill patient is just as important, if not more important, than in healthy patients.  What’s more, intervening early is more beneficial than intervening once the signs of malnutrition are overt.

When do I intervene?

  • As soon as malnutrition is recognised or anticipated
  • Documented anorexia for longer than 3-5 days
  • It is anticipated the patient will be unable to eat within 2-3 days (such as those with oro-facial trauma etc.)

Developing a nutritional plan

  • Successful nutritional support depends on proper diagnosis and treatment of the underlying disease.
  • Assess the animal’s nutritional needs using recent dietary history, physical examination, body weight and condition changes, and laboratory tests.
  • Assign a subjective assessment rating to the patient and reassess every 24 hours.
nutritional plan
  1. Severely and obviously malnourished. Aggressive nutritional intervention is required.
  2. Moderately malnourished or suspected to be malnourished. Needs caloric assessment and encouragement to eat.
  3. Well nourished. No nutritional intervention required at present.

Source: Small Animal Clinical Nutrition Chapter 25 page 458. Figure 25-5

What do I feed?

  • Options include:
  • Maintenance pet food
  • Human liquid enteral diets
  • Specialised recovery foods
  • Therapeutic diets
  • Parenteral nutrition

Specialised urgent care formulas such as Hill’s Prescription Diet a/d are the most common form of nutritional support provided for critically ill patients. Hill’s a/d is formulated and balanced specifically for the needs of recovering dogs and cats. It provides high levels of energy, protein and fat. It has high levels of glutamine, which is a major source of energy for the intestinal cells. Levels of arginine, branched chain amino acids, omega-3 fatty acids, zinc, potassium, B complex vitamins, and antioxidants are also increased. These nutrients support skin recovery, tissue synthesis and immune function.3

Hill’s Prescription Diet a/d Canine/Feline is thixotropic, meaning the more it is stirred, the more liquid it becomes. This enables dish, syringe and some types of tube feeding. Therapeutic diets formulated for specific disease conditions may be warranted for pets with an underlying disease. Please keep an eye out for part two: “How to feed my critically ill patient”.

Dr Danielle Page BVSc, Bcomm, Professional Consulting Veterinarian, Hill’s Pet Nutrition New Zealand with Rosie

Danielle completed a Bachelor of Commerce from Sydney University in 2003. She then decided to pursue
a veterinary degree and graduated from Massey University in 2008. She worked as a small animal
veterinarian in Canberra, ACT and then Florida, USA for four years. In 2012 she became the Technical
Services Veterinarian for Florida for a veterinary nutrition company and subsequently, Clinical
Trials Manager for the USA. In 2014 she moved back to NZ with her family and joined the Hill’s
Professional Veterinary Affairs team and is the Hill’s Professional Consulting Veterinarian for NZ.

Dr Danielle Page


  1. Remillard RL, Darden DE, Michel KE et al. An investigation of the relationship between caloric intake and outcome in hospitalized dogs. Vet Ther 2001; 2: 301-310
  2. Saker KE, Remillard RL. Critical Care Nutrition and enteral-assisted feeding. In: Hand et al, editors. Small Animal Clinical Nutrition. 5th edn. Mark Morris Institute, Kansas, 2010: 439-476
  3. Burns K, Yagi K. Nutrition as a life saver in critical care. NAVC Proceedings Veterinary Technician 2017 45-47