Lecture on Anaphylactic Shock and Related Topics
Anaphylactic Shock Overview
- Signs and Symptoms
- Urticaria (hives): red and warm
- Increased heart rate
- Difficulty in breathing (DIB/SOB)
- Blood pressure decrease (in severe anaphylaxis)
- Angioedema or facial swelling
- Severe abdominal cramping, nausea, vomiting, diarrhea
- Allergen Entry Methods
- Ingestion
- Injection (e.g., bee sting)
- Inhalation
- Absorption through skin or eyes
- Immune Response
- Previous exposure required for true anaphylaxis
- Immune system remembers allergen as foreign
- Release of IgE triggering T cells and histamine release
- Histamine: potent vasodilator and bronchoconstrictor
Effects and Treatment of Histamine Release
- Benefits of Histamine
- Vasodilation to speed detoxification
- Dangers
- Over-vasodilation leads to life-threatening conditions
- Blood pressure drops, blood leaks into skin causing hives
- Angioedema in areas with less fat (eyelids, lips, throat)
- Wheezing and breathing difficulty due to airway constriction
Treatment Based on Severity
-
Mild Reaction
- Symptoms: rash only, BP > 90, no airway involvement
- Treatment: Dipahydramine (Benadryl) 12.5-50 mg
-
Moderate Reaction
- BP > 90 with airway involvement
- Treatment: Epinephrine (epi) 1:1000, 0.3 mg IM + Benadryl
- Can target treat symptoms with Solumetrol (for swelling) and Albuterol (for wheezing)
-
Severe Reaction
- BP < 90, requires immediate intervention
- Treatment: Epi 1:10,000, 0.3 mg slow IV push to prevent tachycardia
- Additional treatments: Benadryl, Albuterol, steroids, fluid challenge
- Epi drips mentioned for severe cases
Anaphylaxis vs Anaphylactoid
- Anaphylaxis
- Requires prior exposure
- Commonly associated with known allergens
- Anaphylactoid
- First exposure reaction
- Treatment is the same as anaphylaxis
Psychogenic Shock (Panic Attacks)
- Signs and Symptoms
- Difficulty breathing, tingling in hands, chest pain
- Hyperventilation symptoms: hyperoxemia, hypocarbia
- Causes and Responses
- Triggered by mental-emotional stress
- Sympathetic nervous system activation
Blood Gas Analysis
- ABG Normal Ranges
- pH: 7.35-7.45
- Pulse ox: 96-100%
- End-tidal CO2: 35-45
- Bicarbonate (HCO3): 22-26 meq/L
- Understanding Changes
- Hyperventilation leads to decreased CO2, respiratory alkalosis.
- Metabolic and respiratory acidosis/alkalosis and their causes.
Sepsis
- Stages and Indicators
- Early Sepsis: BP down, temp up, sugar up
- Late Sepsis: BP normal, temp and sugar down
- Originates from untreated infections (e.g., UTI)
- Treatment
Hypovolemic vs Hemorrhagic Shock
- Hypovolemic Shock
- Caused by fluid loss (e.g., vomiting, diarrhea)
- Hemorrhagic Shock
- Related to blood loss
- Stages 1-4 based on severity
Catheter and Fluid Administration in Trauma
- IV Catheter Selection for Trauma
- Prefer short and wide catheter (e.g., 16 gauge, 1.25 inch)
- Avoid long catheters due to increased turbulence
- Fluid Rate
- 25 cc/hour unless major blood loss
This summary captures the main points and treatments discussed in the lecture, focusing on the understanding of anaphylactic shock, psychogenic shock, sepsis, and other related medical conditions.