Anaphylactic Shock Pathophysiology Quiz and Flashcards

Study Notes

Anaphylactic Shock

Anaphylactic shock is a life-threatening condition that can occur rapidly, but can often be prevented.
Patients with known allergies should understand the consequences of subsequent exposure to the antigen and wear medical identification listing their sensitivities.
The antibody-antigen reaction causes the release of substances such as histamines, eosinophil substance, heparin, prostaglandins, leukotrienes, and platelet activating factor 2.
These substances cause systemic vasodilatation, increased capillary permeability, broncho-constriction, coronary vasoconstriction, and urticaria.
Clinical manifestations of anaphylactic shock include:
- Generalized erythema
- Urticaria and pruritus
- Anxiety
- Restlessness
- Dyspnea
- Wheezing
- Chest tightness
- A warm feeling
- Nausea and vomiting
- Angioedema (swelling of the lips, face, neck, and throat)
- Abdominal pain
Medical management of anaphylactic shock involves:
- Intravenous crystalloid
- Intravenous hydrocortisone
- Antihistaminic
- ETT may be needed if laryngeal oedema and steroid are developed
Nursing management involves maintaining an adequate airway, monitoring patient response to the antigen, and providing comfort measures related to dermatological manifestations.

Neurogenic Shock

Neurogenic shock occurs as a result of a loss of balance between parasympathetic and sympathetic stimulation.
Causes of neurogenic shock include:
- Spinal cord injury
- Spinal anesthesia
- Nervous system damage
- Depressant action of medications
- Lack of glucose (e.g. insulin reaction or shock)
Clinical manifestations of neurogenic shock include:
- Hypotension
- Bradycardia
- Warm, dry extremities
- Peripheral vasodilatation and venous pooling
- Decreased cardiac output (with cervical or high thoracic injury)
Medical management of neurogenic shock involves restoring sympathetic tone by positioning the patient properly.
Specific treatment depends on the cause of the shock.
Nursing management involves elevating the head of the bed at least 30 degrees to prevent neurogenic shock when the patient receives spinal or epidural anesthesia.

Septic Shock

Septic shock is a complex and generalized process that involves all organ systems.
Sepsis, severe sepsis, and septic shock represent progressive stages of the same illness.
The most common causative microorganisms of septic shock are gram-negative bacteria, followed by gram-positive bacteria.
Other infectious agents, such as viruses and fungi, can also cause septic shock.
It is estimated that 20-30% of patients with severe sepsis may never have an identifiable site of infection.

Description

Test your knowledge of anaphylactic shock, a life-threatening allergic reaction that can occur rapidly. Learn about the pathophysiology of anaphylaxis and how it can be prevented. Understand the importance of medical identification for patients with known allergies.