Exam I - Lecture VII (Fick Equation, MI compensation, Shock recap) Flashcards
In an avg healthy adult, what is their cardiac reserve?
(Liters/min and % from our baseline)
🚴🏼♂️ In an elite athlete, what is the maximum cardiac reserve?
❤️🩹 In severe cardiac disease, what’s the cardiac reserve?
~23-25 L/min (~400%)
~35-40 L/min, up to 600%
< 0%
08:00
What does the redline represent?
A heart post MI ❤️🩹 (most likely L heart)
*notice the ⬆️ RAP overtime…not good.
12:00
What does point A represent?
Immediate compensation post MI via SNS.
*CO: ⬇️ 2.5 L/min
*RAP: ⬆️ +2
13:30
Immediate compensation post MI involved the SNS.
How does the body compensate overtime (days) and what effects will we see?
Retains fluid & lytes (B,C) > expands fluid volume (C,D) > steadily ⬆️ RAP (C,D) > stretches heart out (E) > worsens heart (if not enough healing has occurred) (F) > HF/shock, possibly death
17:00
How much CO does the healthy, 30yr old male need to perfuse his organs?
5L/min
18:00
Which type of edema is more dangerous and harder to treat?
Pulmonary edema 🫁
23:00
If a patient never returns to 5L/min CO post MI, what continues to occur?
⬆️ fluid retention > ⬆️ RAP > ⬆️ workload on heart
24:00
What do you think occurred from B to C?
From C to D?
B to C = SNS compensation (notice higher RAP)
C to D = some recovery of tissue or treatment with drug to get to normal CO.
25:00
Days after an MI, would you use Epi or NE to aid the failing heart?
Explain your answer.
No. SNS endogenous compensation (NE, Epi) is exhausted. You would want to use something like Digoxin.
27:00
Is it okay to have the RAP at point H for an extended period of time?
~4-5mmHg - this is okay! 👌🏼
Won’t stretch the heart too much (Thanks, Dig!)
29:00
What is a great drug for HF to improve CO?
Digoxin!
29:00
Is arterial pressure (MAP) a reliable VS during shock?
Not really.
*notice you can be at a 15-20% blood loss and still have a MAP of 100…(thanks to SNS and vasoconstriction)
30:00
Swan-Ganz catheters are the GOLD STANDARD for measuring what?
What is a risk of using one?
CO
Risk for puncture
34:00
What are other ways to measure CO besides the Swan-Ganz?
1) Flotrack
2) Dilution test (Cold saline injection & measuring temp; ⬆️ dilution = ⬆️ CO)
3) Fick Equation from arterial and venous blood gases
4) Bloodwork (lactate, pH, coag’s - clot formation)
37:00 & 42:00
In irreversible shock, we are prone to what? (other than demise ☠️)
Sludgy blood flow = clots.
*think microcirculation and O2 delivery 😟
40:00