What is a normal oxygen extraction ratio in a healthy adult?
(20 vol% - 15 vol%)/20 vol% = 5/20 = 25%
What is Beck's triad for the diagnosis of cardiac tamponade?
2. Distended neck veins (JVD)
3. Muffled heart tones
What is the equation for calculating arterial oxygen content (CaO
= (1.39 x Hgb x arterial O
Sat) + (0.003 x PaO
What hemodynamic changes are associated with sepsis?
-Nml to decreased
CARDIAC FILLING PRESSURES
-Normal or elevated
MIXED VENOUS O
-Increased SVR (LATE STAGE)
What are the indicators of global oxygen transport insufficiency (3)?
1. Decrease in
MIXED VENOUS OXYGEN SATURATION
2. Increase in
ARTERIAL-VENOUS OXYGEN CONTENT DIFFERENCE
3. Development of
What are the clinical manifestations of the SIRS?
1. Fever or hypothermia
4. Increased WBC w/ left shift
What are the mechanisms of obstructive shock (2)?
1. IMPEDANCE TO FILLING
2. IMPEDANCE TO OUTFLOW
What is the classic hemodynamic finding of cardiac tamponade?
EQUALIZATION OF DIASTOLIC PRESSURES
of the heart chambers
Why does removal of very little pericardial fluid in tamponade greatly improve the clinical picture?
Tamponade occurs at the
right side of the pericardial compliance curve
where small decreases in volume cause large decreases in pressure
What causes electrical alternans on the ECG of a pt with cardiac tamponade?
Cyclic motion of the heart in a fluid-filled pericardial sac
What is pulsus paradoxus?
A greater than normal
DECREASE in systolic arterial pressure with INSPIRATION