Sepsis Pathophysiology Overview

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Questions and Answers

What causes metabolic acidosis during anaerobic metabolism?

Excessive oxygen in circulation

Increase in bicarbonate levels

Accumulation of carbon dioxide

Lactic acid build-up (correct)

What is the effect of adrenaline during inadequate vascular volume?

Vasodilation

Tachycardia (correct)

Bradycardia

Decreased heart rate

Which receptor mediates the constriction of arteries during sympathetic stimulation?

Muscarinic

Beta 1

Alpha 1 (correct)

Beta 2

What happens to the heart rate during parasympathetic stimulation?

Decreases significantly Signup and view all the answers

What is the expected bicarbonate level in metabolic acidosis?

12.6 mmol/l Signup and view all the answers

Which statement about the lungs during sympathetic stimulation is true?

Bronchial muscles relax Signup and view all the answers

What indicates a low PaO2 in blood gas analysis?

9.85 kPa Signup and view all the answers

What is one of the consequences of lactic acid build-up on cells?

Cell death Signup and view all the answers

How does sympathetic stimulation affect veins?

Constricts the veins Signup and view all the answers

Which of the following parameters indicates a metabolic issue in blood gas analysis?

Low bicarbonate (HCO3) Signup and view all the answers

What triggers sepsis in the body?

An existing infection Signup and view all the answers

What characterizes the immune response in sepsis?

Immunologic overactivity Signup and view all the answers

What effect does sepsis have on capillaries?

They become dilated and more permeable Signup and view all the answers

What happens to intravascular volume during sepsis?

It decreases abruptly Signup and view all the answers

What does DIC stand for in the context of sepsis?

Disseminated Intravascular Coagulation Signup and view all the answers

What is the consequence of reduced oxygen availability in sepsis?

Formation of micro clots Signup and view all the answers

What impacts stroke volume during sepsis?

Decreased intravascular volume Signup and view all the answers

What metabolic change occurs due to lack of oxygen in sepsis?

Conversion of glucose to lactic acid Signup and view all the answers

Study Notes

Sepsis

Sepsis is a life-threatening condition triggered by an existing infection.
It causes a chain of physiological reactions throughout the body.
The normal physiology changes in a step-by-step process.

Pathophysiology

Step 1: Infection (e.g., a cut).
Step 2: Immune response is triggered, leading to inflammation and swelling in the glands in the neck.
Step 3: Hyperactive immune response occurs, resulting in an overproduction of white blood cells (leukocytes), which fight infection.
Step 4: The immune response becomes systemic (throughout the body) instead of local.
Step 5: Capillaries become more dilated and permeable, allowing fluid to leak out of the blood vessels. This results in a decrease in intravascular volume.
Step 6: Decreased blood flow to organs and tissues, and a drop in intravascular volume.
Step 7: Abnormal clotting cascade (DIC) is triggered by the loss of blood volume and tissue damage from metabolic acidosis and vascular permeability.
Step 8: Micro clots form, further restricting oxygen availability to tissues.
Step 9: Lack of oxygen leads to anaerobic metabolism, producing lactic acid, which can be deadly.

Shock

Shock occurs when there is inadequate tissue and organ perfusion (blood flow).
The three main components for effective blood flow are an effective pump (heart), an effective circulatory system (blood vessels), and adequate blood volume (fluid).

Shock Types

Hypovolemic: Due to blood loss or other fluid loss.
Cardiogenic: Due to heart problems like a heart attack or arrhythmia
Distributive: Related to blood vessel issues like neurogenic, septic, or anaphylactic shock
Obstructive: Caused by physical obstructions like tension pneumothorax or cardiac tamponade.
Dissociative: Related to issues with blood oxygen-carrying capacity, like severe anemia.

Blood Gas Values

pH: 7.23 (normal 7.35-7.45), indicating acidosis
PaO2: 9.85 kPa (normal 11-13 kPa) (slightly low)
PaCO2: 3.2 kPa (normal 4.7-6.0 kPa) (low)
HCO3: 12.6 mmol/L (normal 22-26 mmol/L), low bicarbonate
Lactic Acid: 6.2 mmol/L (<2 mmol/L), high lactate

Red Flag Criteria for Sepsis

Systolic BP 40 mm Hg less than baseline
Respiratory rate >25/min
Heart rate >130
Altered consciousness, new confusion
Limited urine output
SpO2 <91%

Important Considerations

Sepsis is a serious condition requiring immediate medical attention.
Fluids (IV fluids) and antibiotics are crucial interventions, as are addressing underlying causes and monitoring organ systems to preserve their function.

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Description

Explore the critical stages of sepsis progression in this informative quiz. Understand how an infection triggers a systemic immune response and the physiological changes that occur. Test your knowledge on the chain reactions from initial infection to systemic effects.