Advanced Hemodynamics - Orlando Health

Advanced Hemodynamic Monitoring
Pulmonary Artery Catheter Combinations
Many PAC consist of combinations of different techniques. Some combinations include CCO/SVO 2
and CCO/CEDV/SVO 2 monitoring capabilities. Other PAC allow for additional pacing ports with
options for ventricular or atrio-ventricular pacing. Similar combinations are available for pediatric
PACs.
Complications
The most common complications of PACs during insertion are arterial puncture, pneumothorax,
hemothorax, air embolism, ventricular dysrhythmia, bundle branch block, complete heartblock, and
catheter knotting or kinking.
If possible, PAC insertion in patients with a left bundle branch block should be avoided because the
ventricular irritation during insertion can result in a third degree heart block. If insertion of a PAC is
unavoidable, the physician should consider inserting a PAC with pacing capabilities.
Complications during the maintenance phase of the PAC include pulmonary artery rupture,
pulmonary infarction, infection, ventricular dysrhythmia, and thrombus formation.
Arterial Pulse Contour Analysis
Principles
This technology analyzes the arterial pressure waveform and provides an estimate of the stroke
volume. It is not a new technology as it was described as early as the 1940s. The principle is based
on the measurement of peak and slope of the arterial waveform, which reflects the stroke volume.
Several different methods are currently available: cold saline calibration technique, lithium
indicator technique, and computer algorithms.
Lithium Indicator Dilution
Lithium indicator dilution requires an arterial catheter for pulse contour analysis, and a peripheral
catheter. Initial calibration is performed using a lithium injection via the peripheral catheter that is
being detected by the lithium-sensing electrode attached to the arterial catheter. This links the
arterial waveform to the cardiac output measured via the lithium dilution technique. The calibration
has to be repeated every eight hours in order to maintain its accuracy. The main parameters
measured are continuous CO, SV, and SVV. It does not provide any information about filling
pressures or volumes. If used in combination with a central venous catheter and CVP monitoring,
afterload (SVR) can be measured. The algorithm used does not depend on the morphology of the
arterial waveform.
If the patient is on lithium therapy, this technology cannot be used. Also, the lithium injection is
contraindicated for patients weighing less than 40 kg and during the first trimester of pregnancy.
Neuromuscular blocking agents can interfere with the lithium sensor and provide inaccurate
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