Clinical Cardiac Part 5 Flashcards
What are the main physiologic determinants of tissue perfusion?
Cardiac output
Systemic vascular resistance
What is the equation for BP?
BP= CO x SVR
What is the equation for cardiac output?
CO= HR x SV
What is stroke volume determined by?
1) Preload
2) Myocardial contractility
3) Afterload
What is shock?
Inadequate tissue perfusion to meet metabolic demand and tissue oxygenation
How is shock classified according to stage?
Compensated
Decompensated
Irreversible
How is shock classified according to physiology?
Cardiogenic
Hypovolemic
Distributive
Obstructive
How is shock classified according to what actually caused it?
Septic
Neurogenic
Hemorrhagic
Anaphylactic
What is compensated shock?
Reflex compensatory mechanism activated and BP to vital organs is maintained
Is there a decrease in BP with compensated shock?
No
What happens in compensated shock?
Sympathetic vascular tone is increased Release of catacholamines RAAS activated HR increased Contractility increased Blood vessels contract shunting blood centrally
What is decompensated shock?
Issue hypoperfusion and onset of worsening circulatory and metabolic derangment including lactic acidosis
Hypotension
Lactic acidosis
Is there a decrease in BP with decompensated shock?
Yes
What is irreversible shock?
Organ and tissue injury is so severe that even if the hemodynamic defects are corrected survival is not possible
Is compensated shock progressive?
No
Is decompensated shock progressive?
Yes
What are the causes of septic distributive shock?
Gram positive Gram negative Fungal Viral Parasitic Myocobacterium
What are non-septic causes of distributive shock?
Inflammatory shock
Neurogenic shock
Anaphylactic shock
What are cardiomyopathic causes of cardiogenic shock?
MI
Myocarditis
Beta-blocker induced
What are arrhythmogenic causes of cardiogenic shock?
Tachyarrythmia
Bradyarrhythmia
What are mechanical causes of cardiogenic shock?
Valvular insufficiency
Valvular rupture
Valve stenosis
What are hemorrhagic causes of hypovolemic stroke?
Trauma
GI bleeding
Retroperionteal bleeding
What are non-hemorrhagic causes of hypovolemic shock?
Third space losses into the extravascular space or body cavities GI losses (vomiting)
What are pulmonary vascular causes of obstructive shock?
Hemodynamically significant PE
Pulmonary HTN
What are the mechanical causes of obstructive shock?
Tension pneumothorax
Pericardial tamponade
What are mixed causes of shock?
Adrenal insufficiency
Thyrotoxicosis
Acidosis
Hypothermia
Cardiogenic shock is what?
Bad pump
Hypovolemic shock is what?
Decreased intravascular volume
Distributive shock is what?
Dilated peripheral vasculature (decreased SVR)
Obstructive shock is what?
Mechanical obstruction of circulatory system
What is cardiac output in cardiogenic shock?
Decreased
What is SVR in cardiogenic shock?
Increased
What is PCWP or CVP in cardiogenic shock?
Increased
What is cardiac output in hypovolemic shock?
Decreased
What is SVR in hypovolemic shock?
Increased
What is PCWP or CVP in hypovolemic shock?
Decreased
What is cardiac output in septic and anaphylactic distributive shock?
Increased
What is SVR in septic and anaphylactic distributive shock?
Decreased
What is PCWP or CVP in septic and anaphylactic distributive shock?
Decreased
What is the cardiac output in neurogenic distributive shock?
Decreased
What is SVR in neurogenic distributive shock?
Decreased
What is PCWP or CVP in neurogenic distributive shock?
Decreased
What is cardiac output in obstructive shock?
Decreased
What is SVR in obstructive shock?
Increased
What is PCWP or CVP in obstructive shock?
Variable
What is an example of third spacing that resulting in hypovolemic shock?
Cirrhosis
What is an example of hypovolemic shock through the skin?
Burns
What is an example of dehydration hypovolemic shock?
Vomiting, diarrhea, decreased intake
What causes distributive shock?
Vasodilation of the vascular beds causes decreased systemic vascular resistance
What are signs of shock?
Hypotension Tachycardia Oliguria Abnormal mental status Tachypnea Cool, clammy, cyanotic skin Metabolic acidosis Elevated serum lactate
How do you stabilize a patient with shock?
Airway Breathing Circulation Disability (neuro) Exposure (check the back and the "nether" regions) *Primary survey
How do you treat shock?
IVF (in bolus)
Vasopressors
US evaluation
Broad spectrum antibiotics if infection (sepsis) thought to be cause
What is unique about shock in kids?
Don’t see hypotension until the very end
What is unique about shock in the elderly?
Medications mask the symptoms
