Therapeutics I Exam VI (Hypovolemic and Cardiogenic Shock)) Flashcards
General Hypovolemic shock and Cardiogenic shock
Are things like hypovolemic and cardiogenic shock acute or chronic conditions?
These are acute and hyper-acute conditions
Define tissue dysoxia.
The imbalance between oxygen supply and demand
What are the four main types of shock?
-Hypovolemic
- cardiogenic
-distributive (sepsis, anaphylaxis)
- obstructive (very advanced shock)
The total water within our bodies represents what percentage of our actual body weight?
60-70% of body weight. This means that if you weight 100lbs, you would have 60-70lbs of water in you.
What two things make up total body water?
Intracellular fluid and extracellular fluid
Intracellular fluid and extracellular fluid make up total body water. Intracellular fluid takes up around ________% of the total body water while extracellular fluid takes up around ________% of total body water.
67%
33%
What two things make up extracellular fluid?
Interstitial fluid and intravascular fluid
What is interstitial fluid?
This is the fluid between the cells.
If edema is present, that means there is too much ___________ fluid.
Interstitial
What is intravascular fluid?
This is your blood
What two things make up intravascular fluid?
Cells (RBCs, WBCs, platelets) and plasma (water, proteins, albumin, clotting factors, etc)
Interstitial fluid and intravascular fluid make up extracellular fluid (33% of TBW). Interstitial fluid makes up around _______% of extracellular fluid while intravascular fluid makes up around _________% of extracellular fluid.
75% of ECF
25% of ECF
What is hemotocrit?
This is the percentage of blood that is actually red blood cells. It is typically between 45-50%
What are some things that can cause insensible/unmeasurable fluid loss?
- surgery leading to loss of skin barrier
- wounds leading to loss of skin barrier
- fever
- mechanical ventilator leading to to increased respiratory losses
- Hyperventilation leading to increased respiratory losses
- hypermetabolism leading to increased water consumption
Aldosterone causes renal ________ reabsorption and ______ will follow it.
Sodium
Water
Vasopressin binding to its V1 receptor causes what to occur?
Arterial vasoconstriction
Vasopressin binding to its V2 receptor causes what to occur?
Free water absorption from renal collecting duct
Define hypovolemia.
Relative net loss of intravascular fluid volume
Define shock.
A general state of circulatory dysfunction resulting in inadequate tissue perfusion and oxygen delivery, thus leading to tissue ischemia and cellular, tissue, and organ dysfunction and/or failure.
Define hypovolemic shock.
State of intravascular volume depletion resulting in inadequate perfusion and tissue oxygen delivery.
Fluid status within the body mainly affects what factor directly related to mean arterial pressure?
Preload
In hypovolemic shock, there is not enough fluid in the vasculature, this causes _________ also know as _________ to decrease. This then lowers stroke volume, cardiac output, and therefore mean arterial pressure.
Preload also known as end disatolic volume
Explain how hypovolemic shock effects preload.
In hypovolemic shock, the body does not have enough intravascular fluid. This means when the heart tries to fill in systole, not enough blood will enter the ventricles which will reduce myocardial stretching, also know as preload. When preload decreases, so does stroke volume which is the amount of blood the heart pumps out in every beat. When stroke volume decreases, that lowers cardiac output which lowers mean arterial pressure therefore reducing perfusion to important organs.
How does the heart try to compensate in states of hypovolemic shock?
In response to a decreased preload, stroke volume, cardiac output, and mean arterial pressure, the body increases heart rate and tone (SVR).
What are the general presentations for both hypovolemic and cardiogenic shock?
Decreased skin turgor (less elasticity), dry mucous membranes, dry axilla, cold extremities, and mental status changes
What are the hemodynamic clinical presentations in hypovolemic shock?
Increased HR, Increased SVR, decreased preload, cardiac output, map, and urine output, and metabolic acidosis
In a very general sense, what is typically the cause of hypovolemic shock states?
Severe bleeding/ hemorrhage (typically due to some traumatic injury)
What are some more general causes of hypovolemia?
- Acute or chronic hemorrhage
- Severe dehydration
- GI losses (think diarrhea)
- renal losses (think excessive peeing)
- insensible fluid loss
- decreased intake
- capillary leaks due to inflammation
What is the order of treatment goals for patient presenting with hypovolemic shock?
- RESTORE PERFUSION AND OXYGEN DELIVERY TO TISSUES
- Stop blood and fluid losses
- Restore volume and maintain adequate oxygen delivery
In order to get volume resuscitation in hypovolemic shock patients, what do we use?
We can use crystalloids like 0.9% NaCl or lactated rings, colloids like albumin, and give blood is they are bleeding.
Vasopressors should only be initiated in hypovolemic shock once _______ _________ has been done.
Volume resuscitation. If the volume is not adequate yet, vasopressors will cause tissue ischemia. But in all honesty, vasopressors will only increase systemic vascular resistance and that really isn’t the problem with hypovolemic shock.
Why do we need to monitor temperature in someone experiencing hypovolemic shock?
If the person becomes too cold, the clotting factors within the blood getting infused will not work as well.
What are crystalloids?
These are electrolyte solutions like 0.9% NaCl, lactated ringers, dextrose 5%.
What are the pros of using crystalloids in hypovolemic shock?
They are usually inexpensive, readily available, and familiar for most staff.
What are the cons of using crystalloids in hypovolemic shock?
It typically fills the extracellular space which is good but has limited intravascular volume expansion which is what we are really trying to increase in hypovolemic shock. Additionally, these can cause edema due to entering the interstitial space.
What are the pros of using colloids like albumin in hypovolemic shock?
Albumin has much greater expansion into the intravascular space.
What are the cons of using colloids like albumin in hypovolemic shock?
They are expensive, there is limited availability, and it can cause adverse reactions.
T or F: D5W is commonly used to add volume in hypovolemic shock patients.
False. D5W will follow water and only about 10% of the total volume given will actually enter the intravascular space.
What are different example of colloids?
Whole blood, packed RBCs, fresh frozen plasma, platelets, human albumin
What is the most common crystalloid used in hypovolemic shock?
0.9% NaCl
Most hypovolemic shock states are caused by intense bleeding. What are some hemostatic agents used in these acute conditions to stop bleeding?
TXA, desmopressin, activated factor VII, prothrombin complex, idarucizumab, and andexanet alfa
Cardiogenic shock is typically an extension of what chronic condition?
Chronic heart failure
What are the two types of acute heart failure?
Acute decompensated heart failure and cardiogenic shock
Define cardiogenic.
Related to myocardial function
Define cardiogenic shock.
Persistent hypotension, tissue hypoperfusion, and decreased oxygen delivery due to impaired cardiac function in the presence of adequate intravascular volume.
In cardiogenic shock, the heart is not functioning properly, this means that __________ has decreased which directly decreases stroke volume, cardiac output, and then mean arterial pressure.
Contractility
Hypovolemic shock disrupts ________ while cardiogenic shock disrupts _________.
Preload
Contractility
What are the two compensatory mechanisms that are activated in cardiogenic shock?
Increased heart rate and tone
Thinking about the Frank-Starling curve, what would happen in cardiogenic shock patients if you gave them fluids?
Giving fluids in those with symptomatic heart failure and cardiogenic shock will actually cause them overload and decrease stroke volume and cardiac output.
What are the hemodynamic clinical presentations in cardiogenic shock?
Increased heart rate and systemic vascular resistance, normal or high preload, decreased cardiac output, map, and urine output, and metabolic acidosis.
If a patient is presenting with cardiogenic shock but is dehydration/hypovolemic, do you treat the fluid loss first or cardiogenic shock first?
First give fluids to correct the hypovolemia then fix the cardiogenic shock
What are some causes of cardiogenic shock?
Myocardial injury or strain, mechanical heart issue, arrhythmias, prolonged bypass
What is the order of treatment goals for patient presenting with cardiogenic shock?
- RESTORE PERFUSION AND OXYGEN DELIVERY
- Protect airway and give oxygen
- Fluid management (not giving a bunch of fluids like you would in hypovolemic shock)
- Prevent myocardial injury or hemodynamic compromise
What is the first-line medication treatment for cardiogenic shock?
Inodilator like dobutamine
What is the second-line medication treatment for cardiogenic shock?
Milrinone
What are the 5 clinical endpoints for shock patients?
- Maintain MAP
- Maintain oxygen delivery
- Normalize preload
- normalize cardiac output
- normalixe systemic vascular resistance
What is the MOA of inodilators like dobutamine and milrinone?
These guys increase contractility of the heart while decreasing systemic vascular resistance through vasodilation.
