Hemodynamics and Ventricular Function: Clinical Application Flashcards
pulmonary artery (PA) catheter
aka PA line or Swan-Ganz catheter
consists of:
balloon tip with thermistor
computer input
pulmonary artery pressure port
right atrial pressure port (medication infusion)
balloon port (inflate and deflate balloon)
uses of the PA catheter
determine cause of pulmonary edema (cardiogenic vs. non-cardiogenic)
determine type of shock (cardiogenic vs. hypovolemic vs. distributive)
determine cardiac output
contraindications for the PA line
vascular access issues
left bundle branch block
acuse pulmonary embolism, right atrial thrombus, or right ventricular thrombus or mass
process of inserting the PA line
can be done without x-ray guidance
look at pressure waves:
big step-up in ventricles
diastolic pressure steps up in PA
A and V waves in the pulmonary wedge
normal CO
4-8 L/min
normal CI
2.5-4.0 L/min/m2
normal SV
50-100 mL
normal SVI
25-50 mL/m2
normal SVR
800-1200 dynes-sec/cm5
normal PVR
<240 dynes-sec/cm5
tall atrial A waves
tricuspid stenosis
pulmonic stenosis
pulmonary HTN
cor pulmonale
cannon A waves
AV dissociation
absence of A waves
atrial fibrillation
prominent C wave
1st degree AV block
prominent C-V wave
tricuspid regurgitation
priminent X and Y descent
constrictive pericarditis
restrictive cardiomyopathy
blunting of the Y descent
cardiac tamponade
What is the pulmonary capillary pressure ann estimate of?
LA pressure, estimating LV EDP if the mitral valve is normal
Fick cardiac output
based on arteriovenous oxygen difference
CO = [O2 consumption]/[1.34 x 10 x Hgb x (arterial O2 sat - mixed venous O2 sat)
thermodilution (TD) cardiac output
thermistor on the distal tip of the PA line
cold saline injection at the RA and then temperature is measured over time
area under the curve = cardiac output
SVR equation
[(mean arterial pressure - central venous pressure)/cardiac output] x 80
PVR equation
[(mean pulmonary artery pressure - PCWP)/cardiac output)] x 80
RA pressure, CO, and SVR in cardiogenic shock
RA pressure increases
CO decreases
SVR increases
RA pressure, CO, and SVR in septic shock
RA pressure decreases
CO increases
SVR decreases
RA pressure, CO, and SVR in cardiogenic shock in hypovolemic shock
RA pressure decreases
CO decreases
SVR increases
mean arterial pressure equation
MAP = (SBP + 2*DBP)/3
pulse pressure equation
SBP - DBP
blood pressure, CO, and TPR
BP = CO x TPR
SV, CO, and HR
CO = HR x SV
pressure, resistance, and flow
resistance = pressure/flow
negative effects of too much preload
increased back pressure and congeestion
increased resistance to subendocardial blood flow
increased myocardial oxygen demand
determinants of ventricular compliance
filling volume (-)
wall thickness (-)
ventricular size (+)
core hemodynamic variables
SV - pump performance
CO - blood flow
RA pressure (CVP) - RV filling pressure
PCWP - LV filling pressure
SvO2 - tissue oxygenation
rule of 6s
RA < 6 mmHg
RV < 30/6 mmHg
PA < 30/12 mmHg
PCWP < 12 mmHg
SvO2 normal range
60% to 80%
any lower, threat to tissue oxygenation
higher can also represent thret to tissue oxygenation
causes of cardiogenic shock
acute MI, acute PE, cardiac tamponade, CHF exacerbation
