Sepsis and Septic Shock

Question 1

What is systemic inflammatory response syndrome?

Answer 1

= constellation of symptoms of systemic inflammation that may or may not be a result of infection (e.g. acute pancreatitis, major trauma inc burns)

Question 2

How does SIRS manifest clinically?

Answer 2

Manifestations include:
• Temperature > 38 or 90bpm
• RR: > 20 breaths/ min or Pa CO2 12, 000 cells/uL or

Question 3

What is sepsis?

Answer 3

> 2 SIRS criteria with known or suspected infection

Question 4

What is severe sepsis?

Answer 4

sepsis with organ dysfunction (CV: hypotension, resp: hypoxaemia, renal: oliguria and/or azotemia, haem: coagulopathy)

Question 5

What is septic shock?

Answer 5

Septic shock: sepsis with refractory hypotension and impaired end organ perfusion despite fluid resuscitation

Question 6

Outline the pathophysiology of septic shock.

Answer 6

1. Inflammatory stimulus triggers production of proinflam mediators (TNF and IL-1)
   
   2. These cause neutrophil-endothelial adhesion, activate the clotting mechanise and generate microthrombi (plus other mediators like leukotrienes, histamin, lipoxygenase, bradykinin) –> disseminated intravascular coagulation
   3. Warm shock occurs where initially arteries and arterioles dilate, decreasing peripheral arterial resistance and CO typically increases
   4. Later CO may decrease, BP falls and typical features of shock appear
   5. At the same time, vasoactive mediators cause blood flow to bypass capillary exchange vessels (distributive effect)
   6. Therefore poor capillary flow from shunting + capillary obstruction by microthrombi decreases delivery of O2 and impairs removal of CO2
   7. This can lead to organ failure (kidney, lungs, liver, brain, heart)
      Coagulopathy may develop because of intravascular coagulation with consumption of major clotting factors and excessive fibrinolysis

Question 7

What are the signs of sepsis?

Answer 7

• Fever
  
  • Tachycardia
  • Diaphoresis
  • Tachypnea
  • BP remains normal
  • Plus other signs of causative infection

Question 8

What are the signs of severe sepsis or shock?

Answer 8

Initial
• Confusion or decreased alertness (early sign especially in the elderly or very young)
• BP decreases (yet skin is paradoxically warm)
Later
• Cool peripheries with peripheral cyanosis and mottling
Specific organ dysfunction occurs (e.g. oliguria, dyspnoea)

Question 9

What 3 Ix are involved in the septic screen?

Answer 9

• Bloods: CRP, WCC, U&E (dehydration), reticulocytes, culture
• CXR: rule out pneumonia
Urinalysis: rule out UTI

Question 10

What is the sepsis six in management?

Answer 10

Sepsis Six 
1. Give oxygen
2. Take blood cultures
3. Give intravenous antibiotics
4. Start intravenous fluid resuscitation
5. Check lactate level
Monitor hourly urine output