Cardiac output depends on stroke volume and heart rate. Hemodynamic monitoring measures parameters like blood pressure, heart rate, and cardiac output to assess cardiovascular function. Both non-invasive and invasive methods are used depending on the patient's stability, with invasive methods providing continuous monitoring but carrying more risks. Hemodynamic monitoring guides medical treatment by providing information on the patient's volume status and response to interventions.

1. HEMODYNAMIC MONITORING
Gradian Health Systems
Basic Principles of Critical Care
CARDIOVASCULAR SYSTEM

2. Disclaimer
Basic Principles of Critical Care Training I Hemodynamic Monitoring
Disclaimer: Gradian Health Systems cannot provide formal recommendations or indications
regarding medical care and clinical service delivery. The tables, checklists, and other clinical
documents referenced in this training have not been validated in all settings. These documents are
intended to serve as examples only. We recognize that all clinical training content and activities
must be customized to meet the needs of each facility and its clinical staff, factoring in available
resources, practitioner skill level, and other environmental considerations.
For any questions regarding the contents or applications of this training,
please contact Gradian Health Systems:
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3. Module 3
Gradian Health Systems
Basics Principles of Critical Care
Cardiovascular System

4. Module 3: Cardiovascular System
MODULE OVERVIEW
Lesson 1 I Cardiovascular System Anatomy and Physiology
Lesson 2 I Hemodynamic Monitoring
Lesson 3 I Shock
Lesson 4 I Fluid Replacement
Lesson 5 I Vasoactive Medications
Lesson 6 I Basic ECG Interpretation
Basic Principles of Critical Care Training I Hemodynamic Monitoring

5. Components of the Gradian CCV SystemLesson 2: Hemodynamic Monitoring
Lesson Objectives
• Explain the concepts of cardiac output and blood pressure
• Describe the methods using in hemodynamic monitoring
Basic Principles of Critical Care Training I Hemodynamic Monitoring

6. Components of the Gradian CCV SystemLesson 2: Hemodynamic Monitoring
Key Concepts
• Cardiac output
• Blood pressure
• Hemodynamic monitoring
Basic Principles of Critical Care Training I Hemodynamic Monitoring

7. Components of the Gradian CCV SystemHemodynamic Monitoring
Cardiac Output
Cardiac output (CO) is the amount of blood pumped by each ventricle in one
minute. CO is a product of stroke volume (SV) and heart rate (HR):
CO = HR × SV
Stroke Volume and Heart Rate
• Amount of blood pumped by each ventricle with each contraction
• Normal stroke volume is 55-100 mls
• Normal heart rate is 60-100 beats/minute
• Mean CO is 5.25 L/min with a range of 4.8-8 L/min
Basic Principles of Critical Care Training I Hemodynamic Monitoring

8. Components of the Gradian CCV SystemHemodynamic Monitoring
Cardiac Output
Cardiac output is an important factor in blood pressure, an increase in cardiac
output will result in an increase in blood pressure while a reduction in blood
pressure will result in a reduction in blood pressure. Factors influencing CO can
be classified as factors affecting heart rate and stroke volume, such as:
• Age – heart rate varies with age
• Autonomic nervous system –sympathetic nervous system increases HR
while parasympathetic nervous system reduces HR
• Volume status – dehydration increases HR
• Body temperature – hyperthermia increases HR
• Fitness levels – higher fitness levels generally result in a lower HR
Basic Principles of Critical Care Training I Hemodynamic Monitoring

9. Components of the Gradian CCV SystemHemodynamic Monitoring
Cardiac Output
Cardiac output is an important factor in blood pressure, an increase in cardiac
output will result in an increase in blood pressure while a reduction in blood
pressure will result in a reduction in blood pressure. Factors influencing CO can
be classified as factors affecting heart rate and stroke volume.
Factors affecting HR
• Age – heart rate varies with age
• Autonomic nervous system –sympathetic nervous system increases HR while
parasympathetic nervous system reduces HR
• Volume status – dehydration increases HR
• Body temperature – hyperthermia increases HR
• Fitness levels – higher fitness levels generally result in a lower HR
Basic Principles of Critical Care Training I Hemodynamic Monitoring

10. Components of the Gradian CCV SystemHemodynamic Monitoring
Factors affecting stroke volume
• Volume status – also know as preload, refers to the blood volume that enters
the right side of the heart or the blood volume in the heart at the end of
diastole (end diastolic volume)
• Contractility of the heart – the force of contraction of the heart (inotropy)
• Positive inotropes increase contractility (adrenaline, calcium and drugs
like dopamine, epinephrine, norepinephrine)
• Negative inotropes decrease contractility (hypoxia, acidosis,
hyperkalemia, hypocalcemia and drugs like beta blockers, calcium
channel blockers, and digoxin)
• Afterload – the resistance to the outflow of the ventricles; includes the
systemic vascular resistance and the aperture of the heart valves
Basic Principles of Critical Care Training I Hemodynamic Monitoring

11. Components of the Gradian CCV SystemHemodynamic Monitoring
Abnormal HR
• Normal adult heart rate is 50-100 beats per minute
• Bradycardia is a resting heart rate of below 50 beats per minute
• Tachycardia is a resting heart rate above 100 beats per minute
Basic Principles of Critical Care Training I Hemodynamic Monitoring

12. Components of the Gradian CCV SystemHemodynamic Monitoring
Abnormal HR
Increasing HR will increase the CO. This is true for rates below 160/min and is
used as a compensatory mechanism when blood pressure is low. However, as
the heart rate increases above 160/min, the time to fill the heart (diastolic filling
time) is reduced, so stroke volume starts to decrease, resulting in reduced CO.
Basic Principles of Critical Care Training I Hemodynamic Monitoring

13. Components of the Gradian CCV SystemHemodynamic Monitoring
Abnormal HR
Bradycardia and tachycardia usually produce clinical signs and symptoms which
may include:
• Sweating
• Palpitations (in tachycardia)
• Dyspnea
• Low blood pressure
Bradycardia and tachycardia that produce clinical signs and symptoms need to
be treated. Treatment depends on the underlying cause.
Basic Principles of Critical Care Training I Hemodynamic Monitoring
• Dizziness
• Weakness
• Fatigue
• Fainting

14. Components of the Gradian CCV SystemHemodynamic Monitoring
Blood Pressure
• Flow is the movement of a quantity of fluid over time and is usually expressed
in L/min. Blood flow is the movement of blood within a blood vessel in L/min
• Resistance is hindrance (impedance) to flow
• Blood pressure has two components: systolic and diastolic
• Normal adult systolic blood pressure (SBP) is 100-139 mmHg
• Normal adult diastolic blood pressure (DBP) is 60-89 mmHg
Basic Principles of Critical Care Training I Hemodynamic Monitoring

15. Components of the Gradian CCV SystemHemodynamic Monitoring
Mean Arterial Pressure
The average pressure in the arteries, which can also be the average force
driving the flow through tissues. MAP can be calculated using the formula:
MAP = DBP + (SBP/3)
• Normal MAP is 60-100 mmHg
• Low MAP means flow to the tissue is reduced; may result in hypoxia and
ischemia
Basic Principles of Critical Care Training I Hemodynamic Monitoring

16. Components of the Gradian CCV SystemHemodynamic Monitoring
Blood Pressure
Function of cardiac output (CO) and systemic vascular resistance (SVR):
BP = CO x SVR
Systemic vascular resistance is dependent on diameter of the blood vessels:
• Smaller the diameter (vasoconstriction), the higher the resistance
• Larger the diameter (vasodilatation), the lower the resistance
Blood flow through vessels is inversely proportional to resistance. The higher the
resistance, the lower the flow. This can result in ischemia.
Blood flow = △P (pressure difference) / resistance
Basic Principles of Critical Care Training I Hemodynamic Monitoring

17. Components of the Gradian CCV SystemHemodynamic Monitoring
Hemodynamic Monitoring
There are several non-invasive and invasive methods of hemodynamic
monitoring within the ICU. Use depends on the stability of the patient. Basic vital
parameters include:
• Heart rate
• Non-invasive blood pressure (NIBP)
• SpO2
• Electrocardiogram (ECG)
• Urine output
Basic Principles of Critical Care Training I Hemodynamic Monitoring

18. Components of the Gradian CCV SystemHemodynamic Monitoring
Hemodynamic Monitoring
Other parameters can include, but are not limited to:
• Central venous pressure monitoring
• Invasive blood pressure (IBP)
• Mixed venous oxygen saturation (SvO2)
• Echocardiography
Basic Principles of Critical Care Training I Hemodynamic Monitoring

19. Components of the Gradian CCV SystemHemodynamic Monitoring
Blood Pressure Monitoring
Invasive monitoring involves insertion of a catheter into an artery and monitoring
beat and variation in blood pressure. Commonly used arteries include:
• Radial (most common)
• Ulnar
• Femoral
• Arteries in the foot
Basic Principles of Critical Care Training I Hemodynamic Monitoring

20. Components of the Gradian CCV SystemHemodynamic Monitoring
Advantages of IBP
• Continuous monitoring
• Accuracy
• Intravascular volume status estimate by evaluating the waveform
• Arterial blood sampling can be done from the line
Disadvantages of IBP
• Infection
• Thrombosis
• Accidental administration of drugs
• Requires skilled personnel to insert
• Requires special equipment (e.g. catheter, transducer, pressure bags etc.)
Basic Principles of Critical Care Training I Hemodynamic Monitoring

21. Components of the Gradian CCV SystemHemodynamic Monitoring
Central Venous Monitoring
A catheter is placed in a large vein, usually the subclavian or internal jugular
veins, and the catheter is advanced to the heart until the catheter tip is at the
junction of the superior vena cava and the right atrium. Normal range is 3-8
mmHg. It is a good indicator of right heart function.
Basic Principles of Critical Care Training I Hemodynamic Monitoring

22. Components of the Gradian CCV SystemLesson 2: Summary
Basic Principles of Critical Care Training I Cardiovascular System Anatomy and Physiology
The parameters of hemodynamic monitoring depend on the level of
hemodynamic stability of the patient. Hemodynamic monitoring is useful in
guiding medical treatment.