anaphylaxis

Question 1

what is the anaphylaxis doing?

Answer 1

It is a type I hypersensitivity reaction. Mast cells are degranulating in his lungs due to IgE immune complex formation, releasing histamines, which is causing smooth muscle contraction and vasodilation/edema. This can cause acute respiratory compromise and cardiovascular collapse. The pruritis is from the transudate from the surrounding vessels.

An anaphylactic reaction usually takes place within minutes but may take longer. The signs and symptoms associated with anaphylactic reactions are listed in Box 19­23. In contrast with a severe edematous reaction, in which respiratory distress occurs rst, both respiratory and circulatory components of depression occur early in the anaphylactic reaction. Anaphylaxis often is fatal unless vigorous, immediate action is taken. Because it occurs often within minutes after contact with the antigen, the dentist should take the following steps (Box 19­24):

Pathophysiologic Basis

1. First contact with antigen results in formation of antibodies by plasma cells.
2. Antibodies circulate in bloodstream (immunoglobulin E [IgE] antibodies).
3. Antibodies attach to target tissues (mast cells near smooth muscle of bronchi).
4. Next contact with antigen may result in combination of antigen with antibody.
5. Antigen-antibody complex causes degranulation of mast cell(s) with release of histamine.
6. Smooth muscle contracts and vessels lose fluid contributing to edema.
7. Acute respiratory distress and cardiovascular collapse may occur within minutes.