IABP- Part 2- Exam 4 Flashcards
Results of Early Inflation
Regurgitation of blood into left ventricle
Premature closure of aortic valve
Decreased stroke volume
Decreased cardiac output
Increased preload
Increased myocardial oxygen consumption
Indications of Late Inflation
Widening of dicrotic notch
Results of Late Inflation
Diastolic augmentation may decrease
Coronary perfusion pressure may decrease
Indications of Early Deflation
Assisted end diastolic pressure will approach patient end diastolic pressure
Assisted systolic pressure may increase relative to patient peak systolic pressure
Results of Early Deflation
Little or no afterload reduction
Increased myocardial oxygen consumption
Increased preload
Retrograde coronary blood flow may occur
coronary steal
Indications of Late Deflation
Assisted end diastolic dip higher than unassisted end diastolic pressure
Assisted systolic pressure may be higher than unassisted peak systolic pressure
Indications of Late Deflation
Assisted end diastolic dip higher than unassisted end diastolic pressure
Assisted systolic pressure may be higher than unassisted peak systolic pressure
Results of Late Deflation
No afterload reduction Afterload may be increased Prolongation of isovolumic contraction Increased myocardial oxygen demand Decreased stroke volume Decreased cardiac output
Patient Factors Affecting Response
Heart rate
Stroke volume
Mean arterial pressure
Systemic vascular resistance
Balloon Factors Affecting Response
Balloon in sheath
Balloon not unfurled
Balloon position in aorta
Kink in balloon catheter
Balloon leak
Low helium concentration
Timing Issues
Proper timing / poor augmentation
Arterial pressure monitoring site
Changing heart rate
Automatic / Manual timing control
Timing / Triggering Issues
Electrosurgical interference
Arrhythmias
Proper Timing / Poor Augmentation
Large stroke volume
Inadequate balloon volume
Improper balloon position
Balloon too small for patient
Proper Timing / Poor Augmentation
Large stroke volume
Inadequate balloon volume
Improper balloon position
Balloon too small for patient
Changing Heart Rate
Pumping most effective if heart rate
between 80 & 100 bpm
Automatic timing vs. manual timing
Electrosurgical Interference
Place return plate directly under surgical site Placement of leads away from surgical site equidistant from surgical plate locate in same plane Use shielded patient cables Limit power setting to power needed
Ectopic Beats
Balloon deflates on ectopic R wave
Let system track and respond
Ectopic Beats
Balloon deflates on ectopic R wave
Let system track and respond
Tachycardia (HR > 120 bpm)
Compromises diastolic augmentation
Major problem is electromechanical delay
time it takes to physically inflate the
time from trigger (line A) to the start
problems occur when balloon is fixedof balloon inflation (line B) decreases as heart rate increases electromechanical delay is longer than the time from A to B
Atrial Fibrillation
Severe timing problem
Difficult to provide effective afterload reduction
changing R-R interval makes it difficult to predict the next inflation point
Additional Problems
Ventricular fibrillation
Cardiac arrest
Pacemaker spikes
atrial
ventricular
atrio-ventricular
Clinical Criteria for Weaning
Evidence of adequate perfusion
urine output >30 mls/hour
improved mental status
warm skin temperature
No evidence of congestive heart failure
rales absent
S3 absent
No life threatening arrhythmias
Hemodynamic Criteria for Weaning
Cardiac index >2.0 L/min/m2
MAP >70 mmHg (minimal pressor)
PAEDP / PAWP / LAP
IABP Complications
Inability to advance catheter 2 to 13.5%
Inability or difficulty unwrapping balloon 5 to 7%
Ischemic extremities 5 to 47%
Thrombosis of emboli 1 to 7%
Arterial perforation 2 to 6%
Bleeding 3 to 5%
Infection 2 to 4%
Aortic dissection 1 to 3%
Thrombocytopenia rare