Bloat is a life-threatening condition that affects large, deep-chested dogs. Bloat happens when the stomach is distended with air or gas and twists. The twisting of the stomach prevents the dog from being able to get rid of the excess air or gas, resulting in a lack of blood returning to the heart. The dog could go into shock if its blood pressure drops. Seek medical attention immediately as there is an elevated risk of death when this happens. Symptoms include a distended abdomen, excessive salivation, and dry heaves.