The primary objective of emergency care for your cat is to prevent further injury, alleviate pain and distress, and to help start the recovery process. Getting veterinary care is always your top priority - don't try to solve your cat's medical problems on your own.

When your cat gets hurt, make sure you get it to a safe environment.  Next, assess his condition and rank the problems from most severe to least.  Broken bones and external bleeding can be easily detected, while more serious problems could easily be overlooked as they are not visible.  Check that your cat responds to you saying his name or stroking his head.  If he does not, check the ABCs:  Airway (is something in the throat obstructing the airway?), Breathing (is your cat breathing?), Circulation (can you feel a pulse?).  If these are not present, you need to start cardiopulmonary resuscitation (CPR).  If your cat does respond, take your cat's respiration rate (normal - 20-40 breaths per minute) and its pulse.  If possible, take your cat's temperature with a digital rectal thermometer (normal - 101-102.5 degrees Fahrenheit).  Lastly, observe the colors of your cat's gums - they should be pale pink.  White gums may indicate severe anemia, bluish gums may indicate inadequate oxygenation, yellowish gums may indicate liver disease, and small red spots are called pinpoint hemorrhages and can indicate bleeding problems.

Taking your cat's pulse
Place your fingertips along the inside of the thigh, on the femoral artery, in the groin area.  Count for 15 seconds and multiply the number of beats by four.  Normal pulse is 160-240. 

Performing CPR
Use the ABCs to administer CPR.  First, check to make sure that your cat's airway is clear if he's not breathing.  Lay him on his back and tilt his head back to open the airway.  Place your mouth over his mouth and nose and blow gently.  His chest should rise - if not, he has something blocking his airway.  Do a finger sweep (hook your finger, put it in the back of your cat's mouth and swipe from one side to the next to see if you can feel something) but don't poke your finger down his throat - you could push whatever is in there further.  Also try readjusting his head so that you are sure his airway is open (up and back).  If his chest does rise, take your mouth off of his to let him exhale.  Continue this process until your cat starts breathing on his own.  You need to either have help coming or be on your way to getting help at this point.

If the A and B steps don't help your cat breathe, double-check to make sure he has a pulse (step C).  If he doesn't have a pulse, roll him onto his right side.  Place your four fingers behind the cat's elbow, on the ribcage.  Put your other four fingers behind your cat's elbow, on the ribcage, and one inch lower than your other fingers (less space for small cats, more for larger cats).  Push four times, then breathe once.  Continues this process for one minute, and check for a pulse again.  Once you find a pulse, return to step A until your cat is breathing on its own.