Shock

Question 1

What are the types of distributive shock?

Answer 1

• Septic shock (most common)
• Anaphylactic shock
• Neurogenic shock

Question 2

What is the pathogenesis of neurogenic shock?

Answer 2

Damage to CNS –> loss of SANS –> hypotension, bradycardia, respiratory arrest

Question 3

What is the pathogenesis of Anaphylactic shock?

Answer 3

Type I hypersensitivity to allergen
* Mast cells & Basophils –> histamine –> vasodilation & capillary fluid leakage

Question 4

What is the pathogenesis of Septic shock?

Answer 4

Excessive inflammation due to disseminated infection resulting in fluid extravasation from vascular space & loss of intravascular volume

Question 5

Physical obstruction of blood flow in central vessels of systemic or pulmonary circulation can lead to what type of shock?

Answer 5

Obstructive shock

Question 6

Arrhythmias or myocardial damage that disrupt the hearts ability to maintain cardiac output can lead to what type of shock?

Answer 6

Cardiogenic shock

Question 7

Severe fluid loss (third spacing, hemorrhage, or fluid loss) can lead to impaired tissue perfusion and cellular hypoxia and can cause irreversible organ damage in what type of shock?

Answer 7

Hypovolemic shock

Includes hemorrhagic shock

Question 8

What is third spacing?

Answer 8

When fluid moves from intravascular space to interstitial fluid (third space) between cells that is non-functional

Question 9

Define sepsis.

Answer 9

• Body temp: < 36°C or > 38°C
• HR > 90 bpm
• Tachypnea: RR > 20 bpm; PaCO2 < 32 mmHg
• WBC < 4,000/mm^3 or > 12,000/mm^3 or > 10% immature neutrophils

SIRS

Question 10

What are the SIRS criteria?

Answer 10

3Ts w/ white sugar
* Temperature
* Tachycardia
* Tachypnea
* WBC

Question 11

Define sever sepsis.

Answer 11

Sepsis + organ dysfunction (≥ 1 organ)

Question 12

Define septic shock.

Answer 12

Sepsis + hypotension and hypoperfusion despite adequate fluid resuscitation

Question 13

Macrophages facilitate sepsis via which molecules?

Answer 13

• CRP from liver
• Procalcitonin

Question 14

LPS from GNBs can induce proinflammatory cytokines via stimulation of what receptor?

Answer 14

TLR-4

Interacts with PAMPs; IL-1, IL-6, TNF-α

Question 15

Explain the procoagulant state of septic shock.

Answer 15

• Intravascular hypovolemia leads to triggering of extrinsic coagulation cascade
• Disseminated intravascular coagulation (DIC) and microvascular thrombosis

Question 16

Describe metabolic abnormalities of septic shock.

Answer 16

• Pro-inflammatory cytokines suppress insulin release
• TNF-α, IL-1, glucagon drive gluconeogenesis leading to hyperglycemia

Question 17

What are the pathophysiologic stages of septic shock?

Answer 17

• Local activation of inflammatory mediators
• Generalized endothelial dysfunction
• Procoagulation
• Metabolic abnormalities
• Organ dysfunction
• Death or survival

Question 18

What molecules released by macrophages lead to leukocyte recruitment by promoting adhesion of leukocytes to endothelium and their migration through vessels?

Answer 18

TNF-α and IL-1

Question 19

Th1 releases what molecule to stimulate macrophages?

Answer 19

INF-γ