PRIN 3 - Test 3 AnesCardSurg YSK Flashcards
What is the MAP range where autoregulation of Coronary perfusion pressures occur?
60-140 mmHg
What is the most useful measure of coronary perfusion?
MAP
In patients with CAD autoregulation ceases beyond a partial obstruction. In these patients what happens to coronary perfusion and at what MAP does this occur?
Coronary perfusion (flow) becomes pressure dependent; MAP < 70mmHg
When does most (80%) of the blood flow to the LV, during Diastole or Systole?
During this time, Is LVEDP high or low?
Diastole
Low
Decreasing HR has what effect on filling time and O2 demand?
Decrease HR, Increases filling time and Decrease O2 demand.
Subendocardial ischemia is associated with what EKG changes?
ST Segment depression
What is the effect of increasing HR on O2 demand and diastolic time?
INC HR causes INCrease O2 demand and a DECrease filling time.
Transmural (epicardial) injury causes what changes on the EKG?
ST elevation
What is the most significant cause of perioperative ischemia?
Elevated (High) HR
Intraoperative management of pts with CAD or an elevated LVEDP includes maintaining an adequate ______ and a low _______.
MAP; HR
What is the generally accepted target HR?
Less than 70 bpm
According to Laplace’s law, wall thickening ________ (increase or decreases) wall tension/stress, and chamber dilation _______ (increases or decreases) wall tension/stress?
Decreases;
Increases
What happens to the EF with Concentric Hypertrophy and Eccentric Hypertrophy?
Concentric - No change in EF
Eccentric - DECrease in EF
Pts with concentric hypertrophy have a thick LV that is caused by elevated?
LVEDP
Management of Pt with LVH are managed by maintaining a (higher/lower) MAP and a (higher/lower) HR?
Higher MAP
Lower HR
The compensatory response to LV volume overload is characterized by (3)?
LV volume overload causes
eccentric ventricular hypertrophy,
HF
DECreased EF
The pathophysiologic sequence of developing myocardial ischemia.
Ischemia cascade
Ischemia cascade
Myocardial O2 supply and demand imbalance –> Diastolic Dysfunction –> Systolic Dysfunction –> ECG changes –> Clinical symptoms –> MI, CHF, Shock
In the Ischemia cascade diastolic dysfunction leads to ventricular stiffening and decreased compliance which causes what type of (vessel) pressure change?
INCrease Pulmonary Artery End Diastolic Pressure (PAEDP)
What are the ischemia monitors?
TEE
ECG Leads V4, V3 and V5
A powerful biomarker for diagnosis, determination of severity, and prognostication of heart failure released primarily from the ventricles.
B-type natriuretic peptide (BNP)
Concentric LVH (Ventricular Remodeling - Thick) occurs in response to _________ and leads to ________ failure>
Pressure overload,
Diastolic
Eccentric LVH (Ventricular Remodeling - Dilatation) occurs in response to _________ and leads to ________ failure>
Volume overload
Systolic
Normal EF = %
Mild Systolic Dysfunction = %
Moderate Systolic Dysfunction = %
Severe = %
Normal EF = 55% or greater
Mild Systolic Dysfunction = 45-54%
Moderate Systolic Dysfunction = 35-44%
Severe = less than 30%
Causes of Systolic Dysfunction include?
CAD
Dilated cardiomyopathy
Chronic volume overload (MR, AR and high output failure)
Later stages of chronic pressure overload (AS and chronic HTN)
Demand Ischemia is caused by concentric or eccentric LVH?
Concentric LVH, INC in wall thickness and DEC in compliance.
When managing a patient with Concentric LVH the patients are prone to _________, thus the MAP must be keep _______ (high or low) and HR _______ (fast or slow)?
Ischemia
HIGH MAP
Slow normal HR (is CRUCIAL)
A pt with Concentric LVH what happens with regards to chest compressions during CPR
Chest compressions rarely generate enough pressure to perfuse the hypertrophied, noncompliant LV.
A type of RHF caused by pulmonary hypertension that causes systemic venous congestion, hepatomegaly and peripheral edema.
Cor Pulmonale
What is the goal in managing RHF?
Improve contractility and reduce right heart afterload.