INVASIVE HEMODYNAMIC MONITORING
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Transcript INVASIVE HEMODYNAMIC MONITORING
INVASIVE
HEMODYNAMIC
MONITORING
Presentation by Donna Cohen, BSN, RN
Heart and Vascular Center
Medical University of South Carolina
February 2006
INVASIVE HEMODYNAMIC
MONITORING
Objectives
Verbalizes purposes of Hemodynamic
Monitoring
Verbalize indications for Hemodynamic
Monitoring
Identify components of a Pulmonary Artery
Catheter[Swan-Gantz]
Verbalize necessary equipment needed
Objectives [con’t]
Identify the correct pressure waveforms
Identify the components of invasive
hemodynamic monitoring[RA,PA,PAM and
PCWP]
Identify “normal” parameters for each
component of monitoring
Verbalize how to troubleshoot abnormal
waveforms
Objectives [con’t]
Verbalize definition of preload and afterload
Verbalize what and where to document data
collected
Verbalize understanding of the Critical Care
Hemodynamic Monitoring Policy [C1]
Introduction
Swan-Ganz catheter has been in use for
almost 30 years
Initially developed for the management of
acute myocardial infarction
Now, widespread use in the management of a
variety of critical illnesses and surgical
procedures
Purposes of Invasive Hemodynamic
Monitoring
Early detection, identification, and treatment
of life-threatening conditions such as heart
failure and cardiac tampanade
Evaluate the patient’s immediate response to
treatment such as drugs and mechanical
support
Evaluate the effectiveness of cardiovascular
function such as cardiac output and index
Indications for Hemodynamic
Monitoring
Any deficit or loss of cardiac function: such
as AMI,CHF,Cardiomyopathy
All types of shock;cardiogenic,neurogenic,or
anaphylactic
Decreased urine output from dehydration,
hemorrhage,G.I. bleed,burns,or surgery
Components of a Pulmonary Artery
Catheter
Components of Swan-Ganz [con’t]
Normally has four[4] ports
Proximal port – [Blue] used to measure central
venous pressure/RAP and injectate port for
measurement of cardiac output
Distal port – [Yellow] used to measure pulmonary
artery pressure
Balloon port – [Red] used to determine pulmonary
wedge pressure;1.5 special syringe is connected
Infusion port – [White] used for fluid infusion
Components of the Monitoring System
Bedside monitor – amplifier is located inside.
The amplifier increases the size of signal
Transducer – changes the mechanical energy
or pressures of pulse into electrical energy;
should be level with the phlebostatic axis[ you
can estimate this by intersecting lines from
the 4th ICS,mid axillary line
Recorder – please record information
Phlebostatic Axis
Commonly used Terminology
Preload
Afterload
Cardiac Output
Cardiac Index
Systemic Vascular
Resistance [SVR]
Pulmonary Vascular
Resistance [PVR]
Preload
Is the degree of muscle fiber stretching
present in the ventricles right before systole
Is the amount of blood in a ventricle before it
contracts; also known as “filling pressures”
Left ventricular preload is reflected by the
PCWP
Right ventricular preload is reflected by the
CVP [RA]
Afterload
Any resistance against which the ventricles
must pump in order to eject its volume
How hard the heart [either side left or right]
has to push to get the blood out
Also thought of as the “ resistance to flow” or
how “clamped” the blood vessels are
Cardiac Output/Index
Is the amount of blood ejected from the
ventricle in one minute
Two components multiply to make the cardiac
output: heart rate and stroke volume [amount
of blood ejected with each contraction]
Cardiac index is the cardiac output adjusted
for body surface area (BSI)
Computation Constant
Computation constant is based on the
1) type of catheter
2) temperature (iced or room temp) of the
injectate
3) the number of mL’s (5mL vs 10mL) ---we
use 10 mL of room temperature injectate for
our regular swanns, which requires a
computation constant of 0.592
SVR / PVR
Systemic Vascular Resistance – reflects left
ventricular afterload
Pulmonary Vascular Resistance – reflection
of right ventricular afterload
Many of the drugs we administer will affect
Preload, Afterload, SVR/PVR, Cardiac
Output
Possible Complications
Increased risk of infections – same as with any central
venous lines—use occlusive dressing and Biopatch to prevent
Thrombosis and emboli-- air embolism may occur when the
balloon ruptures, clot on end of catheter can result in
pulmonary embolism
Catheter wedges permanently—considered an emergency,
notify MD immediately, can occur when balloon is left
inflated or catheter migrates too far into pulmonary artery
(flat PA waveform)…can cause pulmonary infarct after only
a few minutes!
Ventricular irritation – occurs when catheter migrates back
into RV or is looped through the ventricle, notify MD
immediately…can cause VT
Troubleshooting
Dampened waveform –can occur with physical
defects of the heart or catheter; can be caused by
kinks, air bubbles in the system, or clots
Solution: Check your line for kinks & air
bubbles, aspirate (not flush) for clots, straighten
out tubing or patient as much as possible
No waveform – can occur with non-perfusing
arrhythmias or line disconnection
Solution: Check your line for disconnection,
check your patient for pulse, could also be wet
transducer or broken cable or box
Equipment Needed
SET-UP FOR HEMODYNAMIC
PRESSURE MONITORING
1. Obtain Barrier Kit, sterile gloves, Cordis Kit and correct swan
catheter. Also need extra IV pole, transducer holder, boxes and cables.
2. Check to make sure signed consent is in chart, and that patient and/or
family understand procedure.
3. Everyone in the room should be wearing a mask!
4. Position patient supine and flat if tolerated.
5. On the monitor, press “Change Screen” button, then select “Swan
Ganz” to allow physician to view catheter waveforms while inserting.
6. Assist physician (s) in sterile draping and sterile setup for cordis and
swan insertion.
Equipment Needed
7. Set up pressure lines and transducers [see Critical Care Skills:
Clinical Handbook, Second Edition pages 293 -298]
Please level pressure flush monitoring system and transducers to the
phlebostastic axis. Zero the transducers. Also check to make sure
all connections are secure.
8. Connect tubings to patient [PA port and CVP port] when physician
is ready to flush the swann. Flush all ports of swann before
inserting.
9. While floating the swann, observe for ventricular ectopy on the
monitor, and make physician aware of frequent PVC’s or runs of
VT !
10. After swann is in place, assist with cleanup and let
patient know procedure is complete.
Equipment Needed
11. Obtain your RA [CVP], PAS/D, PAM, and wedge.
For Cardiac Outputs, inject 10 mLs of D5W after
pushing the start button, repeat X 3. Delete outputs
not within 1 point of the mean value. Can use .9NS
instead, but affects the accuracy of the output reading.
12. Before obtaining the cardiac output, please check the
computation constant [should read 0.692 for regular
yellow swans; 0.692 for SVO2 or blue swanns]
13. Perform hemocalculations (enter today’s height and weight).
14. Document findings on the ICU flowsheet.
PA Insertion Waves
Central Venous Pressure (CVP)
Zero transducer to the patient’s phlebostatic axis
Always read CVP at end expiration
CVP is a direct measurement of right ventricular end
diastolic pressure
Right Ventricular Waveform
If the swan falls or gets pulled back into the RV it is
considered a swan emergency.
If you see an RV waveform (looks like VT) pull the swan
immediately.
If the swan remains in the RV it may cause the patient to go
into VT.
Pulmonary Capillary Wedge Pressure (PCWP)
Zero the transducer to the patient’s phlebostatic axis.
Measure the PCWP at end expiration
PCWP should not be higher than PA diastolic
PCWP is an indirect measurement of left ventricular end
diastolic pressure.
Cardiac Output
It is the amount of blood pumped by the heart in one minute.
Calculated by multiplying heart rate times stroke volume.
Cardiac Index is the cardiac output adjusted for body surface
area.
How to read a PA waveform
Measured at end expiration!
Dicrotic notch (closure of PulmonicValve) should always be on
Right side of wave (if notch on Left side find out if the tip in the RV)
Measure PAS at the top of the wave upslope (at end of QRS);
PAD is measured at the trough preceding the systolic peak
(be careful not to measure whip in the wave)
How to read a PCWP (aka wedge)
Measured at end expiration!
After balloon is inflated, compare waveform to respiratory waveform to
determine measurement at the end of expiration
(last clear wave before patient inspires)
Tip: if waveform is difficult to read, try resting hand on pt’s chest as you
wedge; determine where the end of expiration occurs on the wedge
waveform, then measure across several waves for consistency
Documentation
Document PAS, PAD, and PCWP on nursing flowsheet under
Hemodynamic Parameters
PCWP will rarely be > PAD (if so, means blood is flowing
backwards) If PCWP = PAD, look for tamponade
Under circumstances where the catheter will not wedge (or
should not be), do not document any values in the PCWP
column on the flowsheet
If you use the PAD measurement for calculations, it is
acceptable to write ONLY
“PAD value used for calculations”
at the top of your numbers