Management of Anaphylactic reaction (Type 1-Hypersensitivity) During Blood Collection

Management of Anaphylactic reaction

When you can see type 1 reaction:

1. An anaphylactic reaction may be seen in a patient during or after taking the blood sample.
   1. This is basically a typed I Hypersensitivity reaction or Anaphylactic reaction.
2. So every technician should know how to deal with such a situation.

Causes of  Anaphylactic reaction:

1. An anaphylactic reaction may be due to:
   1. Penicillin.
   2. Stings.
   3. Food like nuts, eggs, milk, and fish.

Signs and symptoms of Type-I hypersensitivity reaction:

1. The type-1 reaction may be:
2. The localized reaction is in the form of urticaria and angioedema.
   1. These reactions are severe but not fatal.
   2. There may be physical allergies like heat, cold, sunlight, and pressure.
3. The generalized reaction is also called an anaphylactic reaction.
   1. These are due to the release of primary and secondary mediators.
   2. The affected organs are the cardiovascular system, respiratory, and gastrointestinal systems.
   3. There may be involvement of the skin.

Pathophysiology of anaphylactic reaction:

1. The antigen may be:
   1. Atopic allergies.
   2. Drugs like penicillin.
   3. Insect Stings.
2. The antibody is mainly IgE.
   1. Rarely this reaction may be seen by IgG.
3. The immune cells are mast cells and basophils.
   1. These cells have receptors for the Fc portion of IgE.

4. This is basically a histamine-like reaction or histamine poisoning.

5. The main signs and symptoms are due to the pharmacological reaction of histamine or histamine-like substances.
6. The following diagram gives a summary of the Type 1 hypersensitivity reaction.
   

   Type 1 Hypersensitivity reaction mechanism

The Type 1 reaction takes place in three stages:

1. Stage 1:
   1. The offending antigen attaches to IgE.

1. Stage 2:
   1. Activated mast cells and basophils release mediators.
2. Stage 3:
   1. Mediators released leads to:
   2. Vascular changes.
   3. Activation of platelets.
   4. Activation of eosinophils.
   5. Activation of Neutrophils.
   6. Activation of the coagulation system.
   7. Plasma histamine levels peak more quickly than tryptase at ∼1o minutes after the onset of an anaphylactic reaction.
   8. Its level returns to normal within an hour.
   9. Urine histamine may be elevated for 24 hours.

Chemical mediators are:

1. 1. Histamine increases the vascular permeability and contraction of the smooth muscles.
   2. Leukotrienes cause the contraction of the lung smooth muscle (bronchospasm).
   3. Serotonin causes contraction of the smooth muscles.
   4. PAF – Platelets activating factor leads to the release of histamine and serotonin from the platelets.
   5. ECF-A is an eosinophil chemotactic factor that attracts the eosinophils at the site of antigen and antibody reaction.
      1. ECF-A gives rise to the release of secondary mediators.
   6. Prostaglandins also affect the smooth muscles and vascular permeability.

Clinical presentation of a type-1 hypersensitivity reaction: 

1. Nervousness.
2. Itching and urticaria of the skin.
3. Feeling of confusion.
4. Nausea, vomiting, and diarrhea.
   1. Abdominal or back pain.
5. There will be flushing, pallor, or cyanosis.
   1. Urticaria.
6. Laryngeal edema leads to stridor (laryngospasm).
7. Tachycardia.
   1. There is low blood pressure.
8. Convulsions.
9. Respiratory depression.
   1. Bronchospasm (wheezing) leads to an asthmatic attack.
   2. Respiratory distress is due to edema.
   3. Respiratory obstruction is the main cause of death.

Treatment of anaphylactic reaction:

1. Immediately perform the following measures.
   1. Stop taking the blood sample.
   2. Lie the patient flat and raise the legs.
      

      Blood collection complications and management

   3. Establish an I/V line.
   4. Give normal saline infusion for the hypotension.
   5. Maintain the airway.
   6. Call the doctor for help.
   7. Give an injection of anti-histamine or decadron (hydrocortisone).
   8. Give oxygen if needed.
   9. Monitor blood pressure.
   10. Give cardiopulmonary resuscitation if needed.
   11. If the patient does not improve, then transfer the patient to the hospital.
   12. In case of mild reaction:
       1. Only anti-histamines are enough.
   13. In case of a severe reaction:
       1. First, give epinephrine (1:1000, 0.3 to 0.5 ml subcutaneous)  followed by corticosteroids (Hydrocortisone 100 mg I/V).
          1. Another reference: Give I/M 0.5 ml of 1:1000 epinephrine (Adrenaline).
          2. Repeat after 5 minutes if the shock persists.
       2. Can repeat epinephrine after 20 minutes.
       3. If the airway is completely obstructed and has low blood pressure, repeat epinephrine 1:10,000, 3 to 5 ml I/V at one ml/minute.
       4. Consider dopamine if the blood pressure does not improve.
       5. H1 and H2 receptor blockers are also effective in hypotension.
       6. Corticosteroids help to treat the late-phase reaction.
          1. Late phase reaction occurs 4 to 6 hours after the first reaction and can be as severe or worse than the initial reaction.
          2.  Late phase reaction can occur up to 72 hours, so the observation of the patient is critical.

---