Arterial Lines Flashcards
NIBP diastolic pressure is measured where oscillations become
Attenuated (weakened)
Mean pressure in NIBP corresponds to
Point of maximal oscillations
Systolic and diastolic are calculated
What are the components of IBP?
Indwelling catheter
Fluid filled tubing
Transducer (converts pressure to electric signal)
NIBP often over estimates
Low BP
What is Fourier Analysis?
Summation of sine waves of different amplitudes and frequencies
Reproduces the ABP wave
What two waves make up ABP waveform?
Fundamental wave (pulse) and 63% of the second harmonic wave
During systole, the ________ ejects blood
Followed by peripheral arterial run off during _______
Left ventricle, diastole
Review the graph of ABP relation to EKG
Do it
Indications for ABP
Tight, continuous BP control Hemodynamic instability Monitoring response to vasoactive drugs Monitoring safety of anesthetic techniques (deliberate hypotension, CPB) Prolonged surgical procedures Frequent ABG sampling Unreliable NIBP
Absolute contraindications to ABP
Localized infection at site of insertion
Preexisting ischemia, nerve damage
Reynaud’s phenomenon (vasospastic disorder)
Traumatic injury proximal to site of insertion
Relative contraindications to ABP
Failure to demonstrate collateral flow
Presence of AV fistula in limb
Presence of disrupted lymphatics in limb
Where should the transducer be placed?
At the height of the coronary sinus or at the level of EAC during intracranial surgery
The most common site of cannulation is the
Radial artery
Others include ulnar, brachial,maxillary, femoral, dorsalis pedis
How does distance affect waveform? Pulse pressure \_\_\_\_\_\_\_ MAP \_\_\_\_\_\_ The waveform \_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_ in arrival of pulse at periphery
Widens
Decreases
Narrows
Delay
What causes the difference in waveform that is located more peripherally?
Physical characteristics of vascular tree (impedance and harmonic resonance)
The elderly have _______ arterial distensibility
Reduced
Increased pulse pressure, late systolic pressure peak, attenuated the diastolic pressure wave
How is myocardial oxygen balance affected in the elderly?
Increased systolic demand and decreased diastolic demand. This means a weakened balance.
After releasing pressure on the ulnar artery, no flushing of the hand occurs in 15 sec, this indicates a _______ test and the radial artery should
Negative
Should not be punctured
“Results do not correlate well with outcomes.” WHAT DOES THIS MEAN
How is the transfixation technique different from direct cannulation?
The catheter is advanced completely through the artery and then retracted until blood pulsates freely
T or F. Leveling is not critical to accurate ABP measurement.
False. EAC or left heart 5 cm below sternum in fourth intercostal space
If the bed is raised, the measured ABP will be
Higher
Difference equal to the hydrostatic pressure difference between the two transducers
If a pressure waveform is dampened, the MAP
Remains unchanged
Complications of ABP
Distal ischemia Pseudoaneurysm Arteriovenous fistula Hemorrhage Infection Peripheral neuropathy Misinterpretation of data Misuse of equipment
What is Vigileo?
Minimally invasive assessment of cardiac function
