S. Little
1. Hyporexia/anorexia is never a primary problem; the underlying cause must be identified.
2. Fear and stress can inhibit appetite in hospitalized cats:
a. Use feline-friendly handling techniques.
b. Provide a hiding place in the hospital cage.
c. Have the owner bring familiar bedding, bowls, etc., from home.
d. At admission, record body weight, body condition score, muscle condition score; weigh at least daily.
e. Have a method to record actual amount of food eaten daily, estimate of water consumption, estimate of urine volume, fecal quantity and score, vomiting.
f. Don’t try to introduce a new diet while the cat is still hospitalized; feed a diet the cat is known to prefer.
g. Don’t offer food if nausea is present; wait until nausea is controlled (see table).
h. Have a consistent feeding routine; limit handling during feeding and cage cleaning (consider spot cleaning).
i. Provide non-medical interactions.
3. Know how much to feed:
a. Resting energy requirement estimate: 30x(body weight [kg])+70; adjust as needed.
b. Re-evaluate: if the patient is not eating at least 75–85% of RER daily, institute nutritional support; check serum cobalamin, supplement if required.
4. Advice for owners:
a. Offer fresh and favourite foods.
b. Small frequent meals in a quiet location; may need to isolate cat for feeding in a multi-cat home.
c. Enhance smell by adding flavoured broth, moisten food.
d. Encourage to eat with petting and praise; use hand-feeding.
e. Warm food to just under body temperature.
f. Teach owners to measure food intake: weigh dry food bowl morning and evening, keep track of amount of canned food eaten.
5. Drug therapy:
a. Appetite stimulants (see table): not effective in every patient; may not restore adequate food intake, monitor food intake daily; best for stress-induced or mild hyporexia, to find out if cat can tolerate food after surgery, transition to home; once a cat is totally anorexic, drug therapy seems less effective.
b. Gastric acid blockers (H2 blockers, proton pump inhibitors) are rarely indicated in cats, no antiemetic or appetite-stimulating effects.
6. Assisted feeding:
a. When to start assisted feeding:
i. Anorexia/hyporexia three days or more (count from the first day owner noticed decreased food intake).
ii. Rapid weight loss (>10%) over a short period of time.
iii. Eating <75–85% of RER daily.
b. Syringe feeding, hand feeding: difficult to ensure sufficient food intake, can only feed small volumes at a time (oral capacity of the cat is 1–2 mL), may be stressful for the cat, potential for injury to cat and person feeding.
c. Nasogastric/nasoesophageal tube feeding:
i. Inexpensive, easy to place, may only require light sedation.
ii. Best for short-term use, difficult to maintain at home, can be dislodged by the cat.
iii. Ideal for trickle feeding.
iv. Liquid diets only: most liquid diets are not balanced and can only be used for a few days.
d. Esophagostomy tube feeding:
i. Easy to place with equipment such as the MILA tunneller for esophagostomy tubes, short period of anesthesia required to place.
ii. Almost any diet can be blended with water and used.
iii. Comfortable for the cat, able to eat with tube in place.
iv. Long-term use possible.
v. Use with esophagostomy tube collar (e.g., Kitty Kollar) instead of bandages.
Antiemetic and appetite stimulant drugs for cats
Drug
|
Dosage
|
Comments
|
Antiemetics
|
Metoclopramide
|
0.2–0.4 mg/kg SC, PO q 8 h 1–2 mg/kg/day CRI
|
Poor antiemetic in cats, not recommended
|
Maropitant
|
1 mg/kg IV, SC, PO q 24 h
|
Inhibits substance P binding to NK-1 receptors
|
Ondansetron
|
1 mg/kg, PO, SC, IM, slow IV q 6–8 h
|
5-HT 3 receptor antagonist
|
Appetite stimulants
|
Capromorelin: Entyce (Aratana)
|
1–3 mg/kg PO q 24 h
|
Ghrelin receptor agonist
|
Cyproheptadine
|
1.0–2.0 mg/cat PO q 12–24 h
|
Do not give with mirtazapine (can be used as antidote for serotonin syndrome)
|
Mirtazapine
|
1.88 mg/cat PO q 24 h Give q 48 h in liver or kidney disease
|
5-HT 3 receptor antagonist Appetite stimulant & antiemetic
|
Mirtazapine transdermal: Mirataz (Kindred Bio)
|
Apply 1.5 inch (∼2 mg) to inside of pinna q 24 h (wear gloves); alternate ears
|
|
Phenothiazines: Prochlorperazine, chlorpromazine
|
0.1–0.5 mg/kg SC q 8 h
|
Centrally acting via multiple mechanisms May cause sedation
|
References
1. AAFP/ISFM feline-friendly nursing care guidelines. https://catvets.com/guidelines/practice-guidelines/nursing-care-guidelines. 2012.
2. AAFP/ISFM feline-friendly handling guidelines. https://catvets.com/guidelines/practice-guidelines/handling-guidelines. 2011.
3. WSAVA global nutrition guidelines. www.wsava.org/guidelines/global-nutrition-guidelines.
4. Nasoesophageal and nasogastric tube placement. Clinician’s Brief. www.cliniciansbrief.com/article/nasoesophageal-nasogastric-tube-placement.
5. Esophagostomy feeding tubes. Clinician’s Brief. www.cliniciansbrief.com/article/esophagostomy-feeding-tubes.