Anaphylaxis is a severe allergic reaction. It can cause breathing difficulties, low blood pressure, skin hives, rashes or swelling and gastrointestinal symptoms. Causes usually include allergies to insect bites and stings, drugs or foods. In anaphylactic shock, the allergic reaction acts strongly enough to drop the blood pressure to the point of inadequate delivery of blood to the organs. The condition is life threatening and requires emergency treatment.
Airway, Breathing and Circulation
Cardiovascular support is paramount during anaphylactic shock in order to keep the heart beating and delivering blood to the organs. Fundamental support during anaphylactic shock involves establishing an airway, supporting breathing and circulation. These are known by mnemonic ABC. Cardiopulmonary resuscitation, or CPR, will need to be instituted if breathing or the heart stops. Emergency workers may need to place an oxygen mask over the face or a breathing tube through the mouth in order to deliver enough oxygen to the blood. If the heart stops beating properly, emergency personnel may administer chest compressions, shocks from a defibrillator and drugs to support the cardiovascular system, explains the Mayo Clinic.
Epinephrine
Epinephrine, also known as adrenalin, is a "fight or flight" hormone made by the adrenal gland. In anaphylactic shock, exposure to the allergen causes a massive release of the chemical histamine into the blood vessels, which causes them to dilate and the blood pressure to fall. Epinephrine has the effect of constricting the blood vessels and helping the heart work harder to support the blood pressure and therefore deliver more blood to the organs and dilate the airways. Epinephrine is usually administered by health care workers trained in use of the drug, but people who are known to be at risk of anaphylaxis may carry an EpiPen that can be self administered.
Fluids
Fluids should also be given into the veins. When the veins dilate they serve as a reservoir for blood, and not enough reaches the heart. Fluids such as normal saline or Ringer's lactate can expand the fluid component of blood enough to keep the flow going. This is an important treatment for shock.
Other Treatments
Other drug therapies are available to be used after the person has been initially treated with epinephrine and IV fluids. Antihistamines antagonize the effects of histamine released during anaphylaxis. Steroids such as prednisone suppress the inflammatory response, and inhaled bronchodilators help dilate the airways to improve breathing.
