Introduction
The immune system plays a pivotal role in protecting an individual from many infectious agents and leading a healthy life. The abnormal response can result in life-threatening anaphylaxis, and a weak or absence of response poses risks to individuals to acquire infection. The immune system’s exaggerated response can cause diseases involving multiple organ systems and may complicate anesthetic management. This chapter is an overview of common immune-mediated and infectious disorders.
Anaphylaxis
Anaphylaxis is a life-threatening manifestation of immersive antigen-antibody in which prior antigen detection has evoked antigen-specific IgE antibodies. Vasoactive mediators generated by mast cells and basophils are responsible for anaphylaxis’s clinical symptoms. During anesthesia, anaphylaxis occurs 1 in 5,000 to 20,000 cases. The estimated mortality is 3 to 6%. Risk factors include:
Diagnosis
The clinical symptoms of anaphylaxis may resemble pulmonary embolism, acute myocardial infarction, aspiration or vasovagal reaction. Hypotension and cardiovascular arrest can be the only manifestations of anaphylaxis in general anesthesia patients. The plasma tryptase concentration is elevated within 1 to 2 hours of the alleged reaction, while the plasma histamine returns to baseline 30 to 60 minutes after the anaphylactic reaction. A positive intradermal test result (wheal and flare response) may be obtained, indicating the existence of unique IgE antibodies. The primary and secondary treatment of anaphylaxis is highlighted in Box 21.1.