Hemodynamic
Monitoring
Chapter 65 (pp. 1537-1547)
Content Objective
◦ Apply the principles of hemodynamic monitoring to the nursing and
interprofessional management of patients receiving this intervention.
Overview of Hemodynamic Monitoring
• Provides a means to measure cardiac blood flow
through invasive means
• Essential part of critical care nursing
• Goals of hemodynamic monitoring include:
• Assessment of the body’s response to tissue
oxygen demands
• Alert healthcare team of an impending
cardiovascular crisis BEFORE organ damage
• Evaluate the immediate response of
treatment modalities (medical & nursing
interventions)
Hemodynamic Terminology
Indicator
Preload
Afterload
Other
Hemodynamic measure
Resting normal range
Central Venous Pressure (CVP); Right atrial pressure
2-8 mmHg
Pulmonary artery wedge pressure (PAWP); left atrial pressure
6-12 mmHg
Mean arterial pressure (MAP)
70-105 mm Hg
SBP + 2 (DBP)
3
Stroke volume (SV)=CO/HR
60-150ml/beat
Cardiac output (CO)=SV X HR
4-8 L/min
Cardiac Index (CI)=CO/body surface area
2.2-4 L/min/m2
Arterial hemoglobin O2 sat (SaO2)
95-100%
Mixed venous O2 sat (SvO2)
60%-80%
Hemodynamic
Terminology
Preload
◦ Volume within the ventricle at the end of
diastole
◦ Frank-Starlings Law
◦ The more a myocardial fiber stretches during
filling, the more it shortens during systole and the
greater the force of the contraction
◦ As preload ↑ the force needed in each
contraction ↑ which impacts SV & ultimately
CO
◦ ↑ oxygen demand
Hemodynamic
Terminology
Afterload
◦ The forces opposing ventricular ejection
◦ Includes systemic arterial pressure, resistance from the
aortic valve, & the mass/density of the blood
◦ How can this be measured? (indirectly)
◦ Systemic vascular resistance & arterial pressure  measure
left ventricle afterload
◦ Pulmonary vascular resistance & pulmonary arterial pressure
 measure right ventricular afterload
◦ Outcome
◦ ↑ afterload results in ↓ CO and ↑ O2 demand by the
heart muscle
Hemodynamic
Terminology
◦ Contractility
◦ The strength of the contraction.
◦ Several medications specific to critical care ↑ or
improve contractility.
◦ Why? ↑ contractility= ↑ SV= ↑ CO
◦ Downside= ↑ in SV also ↑ myocardial oxygen
demand
◦ Positive inotropes increase contractility
◦ Epinephrine, norepinephrine, dopamine,
dobutamine, digitalis, calcium, milrinone
◦ Negative inotropes decrease contractility
◦ Calcium channel blockers, B-adrenergic blockers
(beta blockers), & conditions such as acidosis
Hemodynamic Monitoring
◦ 3 Main Devices Utilized
◦ Arterial Line
◦ Used in obtaining arterial blood gas and invasive MAP
◦ Pulmonary Arterial Catheter (Swan-Ganz)
◦ Used in measuring multiple hemodynamic measurements
◦ Central Venous Catheter
◦ Used in measuring central venous pressure with a Swan-Ganz (THINK: right
ventricular filling/preload)
◦ The Arterial Line and Pulmonary Arterial Catheter require a pressurized
fluid system, transducer, monitoring cable, & monitor
◦ 3 steps to hemodynamic accuracy
◦ 1. Referencing (also known as leveling)
◦ 2. Zeroing
◦ 3. Square Wave Testing
Hemodynamic Monitoring:
Leveling
◦ At the phlebostatic axis
◦ 4th intercostal mid-axillary line
◦ Best practice is to use a leveling device.
◦ Relevel with changes in the location of the landmark
◦ Recheck the level of the zero-reference stopcock to
the axis with any change in the patient’s position
before obtaining a reading (if you don’t it won’t be
accurate)
◦ Just about any position can be used to do a zero
reference
◦ Exception is lateral position
◦ Supine, prone, HOB elevated are all ok if completed
accurately
Hemodynamic Monitoring:
Zeroing
◦ Confirms that the pressures measured are that
of the patient
◦ After leveling, the stop cock is turned off to
the patient & cap is removed (maintain
sterility)
◦ Press the “zero” button on the monitor and
wait for the monitor to zero. Replace the cap
and return stop cock to the original position
◦ Please Note…some transducer tubing does
not require the cap to be removed for zeroing.
Check the tubing and policy of hospital!
Hemodynamic Monitoring:
Square Wave Testing
◦ Square Wave Testing (dynamic response test)
◦ Utilized to ensure the waveform is accurate & to
trouble shoot the working of the line
◦ Completed every 8 to 12 hours or more often if
accuracy is questioned
◦ A fast-flush method is utilized.
◦ Determines if the pressurized bag is working
properly, if there are blood clots or air bubbles
in the line.
Types of Invasive Pressure
Monitoring
◦ Arterial Lines
◦ Usually inserted in the radial artery
◦ Allen test
◦ Measures MAP & the systemic blood pressure (systemic vascular
resistance)
◦ ONLY for ABG draws and/or monitoring.
◦ Fluids or medications should NEVER be administered through this
line.
◦ X-ray confirmation is not necessary
◦ Arterial Pressure-based Cardiac Output (APCO)
◦ Newer minimally invasive technique
◦ Provides measuring of continuous CO and CI
◦ Helpful in determining a patient’s response to fluids
Types of Invasive
Pressure Monitoring
◦ Pulmonary Arterial Lines (Swan Ganz)
◦ Long, balloon-tipped catheter with end point
(distal point) is the right side of the heart &
pulmonary artery
◦ Multi-lumen catheter with ports that can be used
for infusions and medication administration
◦ X-ray confirmation IS necessary
◦ This catheter can obtain measurements from the
right and left side of the heart.
Types of Invasive Pressure Monitoring
◦ Central Venous Pressure Lines
◦ Long catheter –placed in the internal jugular, subclavian, or femoral vein
◦ End point – the Superior Vena Cava or Right Atrium
◦ X-ray confirmation IS necessary
◦ Measures central venous pressures/right ventricular filling/ PRELOAD
◦ Multiple ports
◦ Measure CVP
◦ Blood draws
◦ Administration of drugs or fluids that require a central line (i.e. vesicants, Low or High Ph, hypertonic solutions)
◦ Used for a transvenous pacemaker insertion
HEMODYNAMIC MEASURES & WAVEFORMS
Nursing Considerations
◦ Arterial Lines
◦ Assessment
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Arterial site
Collateral circulation (Allen’s test)
Neurovascular status
Monitor site frequently after line is discontinued
Monitor for signs of complications
◦ Infection, occlusion of the artery, hemorrhage, air emboli,
user error (inaccurate readings), damage to the artery
◦ Intervention
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No administration of medications
Appropriate leveling, zero, and waveform
Maintaining line patency
When discontinued:
◦ Gather supplies, remove dressing/sutures, apply pressure
above and over the insertion site for at least 10 minutes or
more
◦ Apply a pressure dressing
Nursing Considerations
◦ Central Venous Pressure Lines
◦ Insertion
◦ Informed consent
◦ Hint: similar concepts related to non-tunneled and tunneled central venous
catheters (air embolism, dislodgement, infection…)
◦ Assessment
◦ Site for dislodgement, redness, drainage, bruising,
◦ Signs of complications
◦ Intervention
◦ Administration of medications and/or infusion
◦ Appropriate leveling, zero, and waveform
◦ Changing dressing
◦ When discontinued:
◦ Gather supplies, remove dressing/sutures, place patient in supine position,
remove while applying gentle pressure to site, and apply occlusive dressing
Nursing Considerations
Pulmonary Arterial Lines
◦ Insertion/Assessment
◦ Note electrolyte, acid-base, oxygenation, & coag status
◦ Informed consent
◦ Same as other invasive lines with additional balloon
complications (air embolism due to balloon rupture,
arterial rupture, and infarction)
◦ Upon insertion the nurse must be prepared to inflate the
balloon
◦ Monitor waveform & EKG
◦ Chest x-ray to confirm placement
◦ Contraindications
◦ Coagulopathy, endocarditis, right heart mass, mechanical
valves
◦ Intervention
◦ When PAWP obtained, inflate the balloon with no more
than 1.5 ml air, obtain value, then deflate the balloon
immediately
◦ Only a special syringe is used for balloon inflation
◦ Notify physician immediately if there is suspicion of
PAWP balloon being inflated for longer than a few seconds
Interpreting SvO2
◦ Obtained by withdrawing blood from a pulmonary wedge catheter (Swan-Ganz)
◦ Monitoring this value can:
◦ Guide interventions
◦ Measured diagnostic to alterations in assessment
◦ Normal is______?
◦ High 80-95%
◦ Physiological response=↑ supply or ↓ demand for O2
◦ Examples
◦ The patient is getting better!
◦ Lower metabolic need- such as with hypothermia
◦ Sepsis
◦ Low <60%
◦ Physiological response= ↓ supply
◦ Examples
◦ Anemia or hemorrhage
◦ Cardiogenic shock
◦ Response to nursing interventions
CIRCULATORY
ASSIST DEVICES
Advanced Learning
Intraaortic Balloon Pump
◦ Provides temporary support to the circulatory system
by
◦ Reducing afterload & supplementing aortic diastolic pressure
◦ Indications for use
◦ Refractory unstable angina
◦ Bridge to a heart transplant
◦ Acute MI with cardiogenic shock, ventricular aneurysm,
ventricular dysrhythmias
◦ Cardiac surgery or high-risk interventional cardiology
procedures
◦ Contraindications
◦ Irreversible brain damage
◦ Major coagulopathy (such as disseminated intravascular
coagulation)
◦ Terminal or untreatable disease process
◦ Aortoiliac disease (peripheral vascular disease) because
impairs placement of the sheath
Intraaortic Balloon Pump
◦ As the balloon inflates & deflates with systole
the left ventricle empties more easily
◦ Outcome
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↑ oxygen delivery to the myocardium
EKG changes –suggest lessening ischemia
↓ afterload
↑ stroke volume
Assessment findings:
◦ Improved mentation, warmer skin, ↑ UO, ↓ HR, ↓
PA pressures, and ↓ crackles
Intraaortic Balloon Pump
◦ Nursing Interventions & Management
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Site infection
Immobilization
Thromboembolism
Hematologic complications
Hemorrhage
Arterial trauma
◦ Avoid HOB higher than 45 degrees
◦ Flexion of the leg at the hip
◦ Balloon leak or rupture
◦ Prepare for emergent removal & reinsertion