First aid for rabbits

Choking

 * AllExperts, Dana Krempels, Ph.D., Rabbit Choking
 * AllExperts, Dana Krempels, Ph.D., Bunny choking
 * Bunny Guy's Blog, Bunny EMT Skills: How to Help a Choking Rabbit
 * Bunspace, Bunny Heimlich Maneuver to clear airway if choking

E-collars
E-collars (AKA elizabethan collars or ecollars) are occasionally used for rabbits to prevent them from chewing on stitches, incisions, or the rest of their body in general.

Some more resources on using e-collars for rabbits:
 * Special Bunny, Surgeries

Syringe feeding
When a rabbit needs nutritional support, syringe feeding with a liquid food is often effective. Oral nutritional support provides calories, nutrients, electrolytes, and fluids as well as help to rehydrate stomach contents and stimulate normal GI motility. The recommended intake is 50ml/kg body weight divided into 3-5 meals per day.

Critical Care is what is commonly fed to rabbits requiring nutritional support. This product can be obtained from your vet or some pet stores and online retailers. Otherwise, you can use your rabbit's normal pellet feed and grind it to powder and mix 1:1.5 with water to form a paste for feeding. Any remaining formula may be refrigerated for 48 hours.

For further instructions in syringe feeding methodology, see Medicating Your Rabbit.