Shock

Question 1

What is shock?

Answer 1

Results from a cause of some type that leads to decreased tissue perfusion which causes cell hypoxia and eventually organ dysfunction and Death

Question 2

What are the different types of shock?

Answer 2

septic (infection)
hypovolemic (fluid loss)
cardiogenic (weak heart)
anaphylactic (allergic)
neurogenic (neuro damage)
obstructive (impending blood flow)

Question 3

What are the different stages of shock?

Answer 3

Initial
Compensatory
Progressive
Refractory

Question 4

What happens in the initial stage of shock?

Answer 4

– Cardiac output is low
– so it cannot support the demands of tissue perfusion or oxygen demands of cells
– so cells switch from aerobic metabolism to anaerobic metabolism
– so lactic acid is created (usually liver converts lactic acid to pyruvic acid which then turns it into glucose (via glucogenesis)
– but live can’t handle the lactic acid because there is not enough cardiac output to perfuse the highly vascularized liver.
— leads to lactic acid buildup (lactic acidosis)

Question 5

What happens during the compensatory stage of shock?

Answer 5

– body senses decreased BP and CO that lead to tissue perfusion
– baroreceptors in carotid sinus and aortic arch stimulate the SNS
– releases catecholamines (epi and norepi) which lead to vasoconstriction
– increases BP, CO, and thereby increasing tissue perfusion to vital organs (brain and heart), shunting from non-vital organs (GI, skin, kidneys, lungs) (kidneys will activate RAAS)
– leads to decreased arterial pressure leading to decreased capillary hydrostatic pressure
– so the fluid moves from interstitial to intravascular
– so increased venous blood flow to heart
– so increased CO, BP, and perfusion.

Question 6

Explain what happens to the GI, skin, and lungs when a patient has decreased perfusion.

Answer 6

GI - works slower — decreased peristalsis — at risk for a paralytic ileus.

Skin - cool, moist, pale — unless it is due to septic shock, then skin will be hot and flushed d/t vasodilation.

lungs - decreased O2 (gas exchange), VQ mismatch — hyperventilation

Question 7

What happens during the progressive stage of shock?

Answer 7

• No compensation
• drop in CO
• drop in tissue perfusion
• decreased O2 to cells
• hypoxic injury occurs
• increase capillary permeability (gates open from intravascular to interstitial space)
• fluids and proteins leave, so loss of blood volume and have massive edema

Question 8

Explain what happens to the neuro, lungs, heart, kidneys, GI, and liver when a patient is in progressive shock.

Answer 8

neuro - MAP > 60, CPP (Cerebral Perfusion Pressure) decreased, slow speech, confused, agitated, decreased pain response

lungs - ARDS (Acute Respiratory Distress Syndrome) - alveoli sac have increased permeability - fluid collects in sacs and collapse - edema, crackles, increased RR, decreased O2

heart - cells not being perfused - muscle dies - AMI, dysrhythmias (Vtach, Vfib, MI)

kidneys - fx of nephron stop working, Acute Tubular Necrosis, renal failure, decreased urinary output, increased BUN and creatine and waste, metabolic acidosis

GI - loses protective chemicals, GI bleeding and ulcers

liver - not filtering waste, increased bacteria and create clotting factors, increased ammonia and bilirubin

DIC (disseminated intravascular coagulation) - micro-clots in vessels, wastes platelets and clotting

Question 9

What happens in the refractory stage of shock?

Answer 9

• all organs shut down and it cannot be reversed