How can you tell whether your dog is suffering from an emergency that requires urgent treatment at 1:00 am, or whether your dog's problem is something that can wait until the morning? Many emergencies are not subtle -- collapse, paralysis, and hemorrhagic diarrhea come to mind. However, some urgently life-threatening problems, such as bloat, can start with symptoms that don't seem like a big deal at first.

1. Difficulty breathing
This is the mother of all veterinary emergencies. After three minutes without breathing it's all over. If your dog is having trouble breathing, or is "breathing funny," making alarming noises when he breathes, or is puffing his lips when he breathes, you need to get to the vet immediately.

2. Restlessness, panting, inability to lie down comfortably, unsuccessfully attempting to vomit, and abdominal distention
These are all symptoms of gastric dilatation with volvulus, known colloquially as "bloat." Bloat is one of the most urgently life threatening situations a dog can face. Some dogs will exhibit all of these symptoms, but others may only pant and act restless. Because of its urgency, dogs exhibiting any symptoms suspicious for bloat should be rushed to the nearest veterinarian.

3. Seizures
Although a solitary seizure is not likely to be life threatening, seizures often come in clusters, which can become progressive. And sometimes seizures are caused by toxins that can cause fatal reactions.

4. Collapse or profound weakness
These can be symptoms of major problems such as internal bleeding (particularly a syndrome called hemoabdomen), cardiac compromise due to a condition called pericardial effusion, anaphylactic shock, certain poisonings, a glandular condition called Addison's disease, and some types of organ failure. All of these problems require urgent veterinary attention.

5. Protracted vomiting and/or diarrhea
This is a veterinary emergency, especially if the liquid produced is significantly bloody. A dog who vomits once or has a single loose bowel movement may not require any treatment other than a few hours of resting the stomach and a day or two of bland food. However, repeated vomiting and diarrhea can rapidly lead to life-threatening dehydration; they also can be symptoms of major problems such as gastrointestinal obstruction.

6. Struggling to urinate
This may simply signify a bladder infection. Bladder infections are painful but not life threatening. However, this symptom could also represent obstruction of the urinary tract by bladder stones -- a situation that is very urgent indeed. Either way, your pet will be best off by seeing the vet since bladder infections, as mentioned above, are painful.

7. Not eating or drinking
You will have to make a judgement call. If my pal Buster (a Labrador Retriever mix, and quite a chow hound) leaves over a piece of kibble, I know something is wrong. Other dogs may intermittently pass up a meal here or there. However, dogs who go a day or longer without eating almost always are sick. And they usually won't drink enough water to cover their needs, so dehydration can set in as well.

8. Loss of use of rear legs
This is especially common in Dachshunds, Corgis, and other so-called chondrodysplastic (think short legs and long backs) breeds, and can be a sign of injury to the spinal cord. This paralysis or partial paralysis is usually very painful, and rapid treatment can make a big difference in outcome.

9. Severe pain
This is always an emergency. If your dog is vocalizing, panting, profoundly limping, or exhibiting other symptoms of agony, don't let him suffer. Get to a vet for treatment.

10. Known exposure to dangerous poisons
This should precipitate an immediate veterinary visit. If you catch your dog munching on snail bait, don't wait for the seizures to start before you go to the vet. Although there are too many dangerous poisons out there to list them all, some of the more common exposures include chocolate, rodent bait, grapes and raisins, human medications, and overdoses of flavored canine medications such as Rimadyl.

 

Source: http://www.pawnation.com/2013/07/16/12-dog-emergencies-that-need-immediate-veterinary-attention/1
Photo source: http://blog.petflow.com