Introduction
Anaphylactic shock in dogs is a real medical emergency that must be treated immediately, as death can happen in less than one hour after exposure to the inciting antigen. This condition cannot be treated by owners at home – intensive veterinary attention and hospitalization are required. At the hospital, dogs in anaphylactic shock will undergo a number of emergency treatments in an attempt to reverse the reaction, treat the signs of shock and stabilize the patient. It is critical that treatment for anaphylaxis begins before any diagnostic testing. Rapid and effective treatment is the main determinant of survival.
Treating Anaphylactic Shock
The goal for treatment of anaphylactic shock in dogs is emergency life support. This is accomplished by providing respiratory and cardiovascular support, removing the causative allergen if possible and taking steps to prevent further release of inflammatory mediators.
In severe cases, the first step in treatment is to place an intravenous catheter and aggressively administer fluids at shock dosages to counteract the hypotension (low blood pressure) caused by severe peripheral circulatory failure. Intravenous administration of epinephrine usually is the next step in treating anaphylactic shock. Epinephrine causes an increase in heart rate and constriction of blood vessels; it also helps to block further release of those compounds in the body which are responsible for perpetuating the anaphylactic reaction (inflammatory mediators). Other medications may be used by your veterinarian to treat shock, such as corticosteroids, atropine sulfate, dopamine or aminophylline, among others.
The veterinary team will take steps to establish an open airway in dogs with difficulty breathing or other signs of respiratory distress. Several methods are available, including placing a breathing tube through the mouth and down the animal’s throat (endotracheal intubation) or making a surgical incision through the neck, directly into the trachea (tracheostomy). Oxygen therapy can be administered if needed. Broad spectrum antibiotics are often given in an attempt to prevent secondary bacterial infections which can develop after an anaphylactic episode.
Frequent in-hospital monitoring of the patient should be continued for at least 24 to 48 hours after the allergic reaction has resolved. This includes monitoring of heart and respiratory rate, respiratory effort, pulse rate and quality, blood pressure, mucous membrane color, mentation and body temperature. Blood samples may be taken to assess liver function and the condition of other organs. The large volume of fluids given to combat shock can cause water retention; in many cases, a recovering dog will not be released from the clinic until he or she can urinate and the effects of fluid retention have resolved.