Anaphylactic  Shock

 

Anaphylactic Shock

Can be fatal

     Anaphylaxis is serious potentially life threatening allergic response.  In severe cases a patient can go into shock in a few minutes and die. 

     77% anaphylactic deaths occur in hospitals. 23% occur outside hospitals.

       In a less severe case specially if the patient survives longer than 30 minutes  it can cause marked swelling, hives, lowered blood pressure dilated blood vessels and difficulty in breathing.

Incidence and cause of it

     It is very rare to see people dying from it. Incidence is about 8 cases per year in a country like Sri Lanka. (Based on numbers from USA and it may be different)   It is very difficult to predict.
 It occur when immune system makes immunoglobulin E antibody against a substance. Later when you are exposed to the allergen a large amount of histamine is released leading to the anaphylaxis.  Commonest causes in Sri Lanka for this kind of severe allergy are, bee and wasp stings. immunizations, antibiotics, radiocontrast media and other injections commonly used in hospitals.

Symptoms of Anaphylaxis

     In a very severe case patients could start collapsing very rapidly.  It can begin wth itchying of eyes and face in other cases. It also causes breathing and swallowing difficulties, abdominal pain, vomitting, diarrhea, hives and swelling under the skin called angioedema.

     This is a medical emergency requiring immediate access to medical care since without treatment or even with prompt treatment at times it can be fatal

Higher with prior allergies

     People with a history of allergies have a higher risk of developing.  This is why you should always tell your doctor about all your allergies.
 If the patient had allergic reactions and is not sure what caused it is possible to do challenge testing  but this has to be done in a hospital setting with a specialist who knows this. Sri Lanka has only a handful of specialists who can handle this properly.   But if an anaphylaxis is suspected skin testing is not recommended.

Life saving first treatment

      
 Only life saving treatment is to give Adrenaline 1 in 1000 one vial by deep intramuscular injection. Call for an ambulance right after that. If you are a lay person and it is available  injection should be to the left anterior thigh.  After five minutes if the response is not adequate another injection should be given

Other treatments later

     . After that intravenous fluids should be started and antihistamines and steroids can be given.  If the patient does not respond to two intramuscular injections of adrenaline then if this happens in a hospital intravenous infusion of adrenaline 1in 1000 mixed to a normal saline can be started.
 If a person has had allergy to bee stings or foods  that person should carry an epinephrine pen and have a medical alert such as a bracelet or pendent or carry a card. That can save a persons life in an emergency.  Apart from that they should carry an adrenalin pen with them at all times. They should learn how to inject themselves into the left thigh so that they can do it in an emergency.

Deaths are rare

    
 http://www.ncbi.nlm.nih.gov/pubmed/24332862

 According to above american study people who present to hospitals or emergency rooms have a 0.25 to 0.33 percent chance of dying.  That comes to about 66-99 deaths annually.  Translated to Sri Lanka this comes to about 5-6 deaths from anaphylactic shock every year.  It shows how rare this event is.

Expert Witness

    In an anaphylaxis death the expert witness is invariably the allergist. 

    It should not be a surgeon or an anesthetist. 

    A general physician has more knowledge about allergies than a surgeon.

    There are three Allergy specialists in Sri Lanka to my knowledge.

Autopsy in a fatal case

http://www.ncbi.nlm.nih.gov/pubmed/10823122

    An autopsy series of 56 deaths in UK from 1992 to 2000 revealed that 19 occured due to bee or wast venom, 16 to foods and 21 to drugs or contrast media.
 14 of 16 cases tested were positive for tryptase levels and three of three tested had detectable IgE to the suspected allergen.