Transcript File - Respiratory Therapy Files

Hemodynamic
Monitoring
Hemodynamics?
 Hemo: blood
 Dynamics: movement
 Hemodynamics: movement of blood
 The measurement of the force (pressure)
exerted by the blood as it moves through
blood vessels or heart chambers during
systole and diastole
 For many critically ill patients, hemodynamic
monitoring can add valuable information to
the clinical management of the patient.
Physiology of Blood Pressure
 Without sufficient BP the tissues will not receive
oxygen.
 High BP strains the heart and vessels.
 3 factors control BP
 Heart
 Blood
 Vessels
Review of Heart Anatomy
 4 chambers serving 4 circulatory branches
 Each Chamber has its own BP.
 Hemodynamics is measuring each of those
pressures.




LV - Systemic arteries
RA – Systemic veins
RV – Pulmonary Arteries
LA – Pulmonary Veins
The Heart
 Muscular 4 chambered organ.
 Pericardium – membranous sac covering heart.
 Epicardium – visceral pericardium
 Myocardium – heart muscle
 Endocardium – Lines the heart chambers
Cardiac Cycle
 Refers to the pumping cycle consisting of
systole and diastole.
 Preload – stretch of ventricle muscle fibers
before contraction, created by enddiastolic volume
 Afterload – Resistance to ejection of blood
during systole.
Preload
 Preload can be defined as the initial
stretching of the cardiac myocytes prior to
contraction.
 For example, when venous return is
increased, the end-diastolic pressure and
volume of the ventricle are increased,
Introduction
 http://www.youtube.com/watch?v=nNpty2
m-EXg&feature=related
 http://www.youtube.com/watch?v=deIeALEjog&feature=relmfu
Types of Catheters
1. Arterial Catheter
2. Central Venous Catheter
3. Pulmonary Artery Catheter
Technical Background
 Liquids are noncompressible
 Pressures at any given point within a liquid are
transmitted equally
 Pascal’s Principle
 When a closed system is filled with liquid the
pressure exerted at one point can be measured
accurately at any other point on the same level
Technical Background
Hemodynamically Unstable
Patients
 Receiving fluid infusion
 Receiving drugs to
 Improve circulation
 Improve heart function
 Improve blood vessel caliber
 Experiencing extremes in blood pressure
 Patients who require serial ABGs
Arterial Catheter
 Common Uses
 Measure systemic Artery Pressure
 Collect arterial blood gas samples
 Indocyanine green C.O. measurement
 Insertion Sites
 Radial, brachial, femoral, dorsalis pedis,
umbilical (neonates)
 Location
 Within systemic artery near insertion site
 Radial artery is the site of choice because of
the collateral circulation to the hand provided
by the ulnar artery
http://www.youtube.com/watch?v=qv54USEYNzw&feature
=related
Arterial Catheter:
Arterial Waveform
1
2
3
 3→1: increase of BP during systole
 2: dicrotic notch
 closure of aortic valve during diastole
 3: Arterial end-diastolic pressure
A-line
 An arterial waveform should have a
• Clear upstroke on the left (ejection)
• With a dicrotic notch (valve closure)
• Down stroke on the right (diastolic runoff)
• A pulmonary artery waveform will look
similar to this waveform, however the
pressures will be lower
Arterial Catheter:
Normal Arterial Pressure
 120/80 mmHg
Systolic (contraction): 100-140 mmHg; min
acceptable 90
Diastolic (relaxation): 60-90 mmHg
Mean: 80-100 mmHg
MAP = (Psystolic + 2 x Pdiastolic)
3
 The diastolic value receives greater weight in this
formula because the diastolic phase is about twice as
long as the systolic phase
 A MAP of 60 mmHg is considered the minimum pressure
needed to maintain adequate tissue perfusion
Arterial Catheter:
Decreased Arterial Pressure
 Absolute hypovolemia
 Blood loss
 Dehydration
 Relative hypovolemia
 Shock
 Vasodilation
 Cardiac Failure
Arterial Catheter:
Increased Arterial Pressure
 Improvement in circulatory volume and
function
 Sympathetic stimulation
 Vasoconstriction
 Administration of vasopressors
Arterial
Pressure
Stroke
Volume
Vascular
Resistance
 Since arterial pressure is the product of stroke volume and vascular
resistance, changes in either parameter can affect arterial pressure
 Opposing changes of these two parameters (e.g. increase in stroke
volume and a decrease in vascular resistance) may present

an unchanged arterial pressure
Arterial Catheter:
Pulse Pressure
Arterial Catheter:
Pulse Pressure
 The difference between arterial systolic
and diastolic pressure.
 Pulse pressure = systolic pressure –
diastolic pressure.
 Bradycardia: low rate allows the blood
volume more time for diastolic runoff and
causes a lower diastolic pressure
 Tachycardia: high rate allows the blood
volume less time for diastolic runoff and
causes a higher diastolic pressure
Decrease Pulse Pressure
 ↓ pulse pressure = early sign of
hypovolemia
 ↓ stroke volume (hypovolemia)
 ↑blood vessel compliance (shock)
 Tachycardia
Increase Pulse Pressure
 ↑ pulse pressure = early sign of vol.
restoration
 ↑ stroke volume (hypervolemia)
 ↓ blood vessel compliance (arteriosclerosis)
 bradycardia
Cardiac Output
 QT or CO = the amount of blood pumped out the
left ventricle and into the systemic circulation.
 CO = HR x SV
 CO = (130 x BSA) / (CaO2 – CvO2)
 Normal is 4 – 8 lpm and depends on body size.
 Measured by thermal dilution technique.
Factors Affecting Cardiac
Output

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


Factors affecting cardiac output in a healthy but
untrained individual could be:
Increase/ decreased in heart rate
Change of posture
Sympathetic nervous system activity
Parasympathetic nervous system activity can also affect
cardiac output.
Heart rate can vary by a factor of approximately 3,
between 60 and 180 beats per minute, whilst stroke
volume can vary between 70 and 120 ml, a factor of only
1.5.
Cardiac Index (CI)
 Used to normalize CO measurements among
patients of varying body size.
 CI = CO/BSA - 2.5 – 3.5 L/min/m2.
 CI values between 1.8 and 2.5 L/min/m2 indicate
hypoperfusion.
 CI < 1.8 L/min/m2 may be indicative of
cardiogenic shock.
Stroke Volume (SV)
 Measures the average CO per one heartbeat.
 ↑ by drugs that raise cardiac contractility and
during early stages of compensated septic
shock.
 ↓ by drugs that lower cardiac contractility and
during late stages of decompensated shock.
 SV = CO / HR
 NV: 40 to 80 mL
Stroke Volume Index (SVI)
 Used to normalize stroke volume
measurements among patients of varying
body size.
 SVI = SV / BSA
 NV: 33 to 47 mL/m2
Factors ↑ SV, SVI, CO, CI
 Positive Inotropic Drugs (↑ contractility)
 Digoxin (Lanoxin), Dobutamine (Dobutrex),
Epinephrine (Adrenalin), Dopamine (Intropin),
Isoproterenol (Isuprel), Digitalis, Amrinone
(Inocor)
 Abnormal Conditions
 Septic shock (early stages), Hyperthermia,
Hypervolemia, ↓ vascular resistance
Factors ↓ SV, SVI, CO, CI
 Negative Inotropic Drugs (↓ contractility)
 Propanolol (Inderal), Metoprolol (Lopressor),
Atenolol (Tenormin)
 Abnormal Conditions
 Septic shock (late stages), CHF,
Hypovolemia, Pulmonary emboli, ↑ vascular
resistance, MI
 Hyperinflation of the Lungs
 MV, CPAP, PEEP
Ejection Fraction
The ejection fraction is a measurement of the heart's efficiency and can
be used to estimate the function of the left ventricle, which pumps blood
to the rest of the body. The left ventricle pumps only a fraction of the
blood it contains. The ejection fraction is the amount of blood pumped
divided by the amount of blood the ventricle contains. A normal ejection
fraction is more than 55% of the blood volume. If the heart becomes
enlarged, even if the amount of blood being pumped by the left
ventricle remains the same, the relative fraction of blood being ejected
decreases.
For example:
 A healthy heart with a total blood volume of 100 mL that pumps 60
mL to the aorta has an ejection fraction of 60%.
 A heart with an enlarged left ventricle that has a total blood volume
of 140 mL and pumps the same amount (60 mL) to the aorta has an
ejection fraction of 43%.
 A reduced ejection fraction indicates that cardiomyopathy is present.
Arterial Catheter:
Transducer Position
 To ensure accurate measurements, the
transducer, catheter, and measurement
site should all be at the same level
 Transducer or catheter higher than site:
false ↓ pressure reading
 Transducer or catheter lower than site:
false ↑ pressure reading
Arterial Catheter:
Complications
 Ischemia
 Hemorrhage
 Infection
• Ischemia secondary to embolism, thrombus, or arterial spasm
evidenced by pallor distal to the insertion site and usually
accompanies by pain and paresthesis
• Hemorrhage if disconnect or open stop cock
• Infection as with all invasive lines, risk increases dramatically after 4
days
• Fever in any patient with a line in place must trigger questions about
the necessity of the lines and their role in the infection process
Central Venous Catheter
A multiple lumen catheter like this one
•Allows the infusion of blood and various medications through different
ports
•Permits aspiration of blood samples
•Or injections for cardiac output measurements without the interruption of
medications
http://www.youtube.com/watch?
v=coEpM7IBzsM&feature=relat
ed
Central Venous Catheter:
Central Venous Pressure (CVP)
 CVP is pressure of the blood in the
 Vena cava
 Right atrium
 Right ventricle
 CVP is also referred to as
 Right atrial pressure (RAP)
 right side preload
 Right ventricular end-diastolic pressure
(RVEDP)
Central Venous Catheter:
Central Venous Pressure (CVP)
 CVP measures right heart function and
fluid levels
 Transducer is placed at level of RA
 Normal


2-6 mmHg by transducer
4-12 cmH20 by water manometer
Central Venous Catheter:
Indications
 Assessment of right ventricular function
and intravascular volume status
 Administration of fluids, parenteral
nutrition, blood, or drugs
 Emergency route for temporary
pacemaker insertion
Central Venous Catheter
 Common Uses
 Measure central venous pressure
 Administer fluid, blood, or medications
 Aspiration of blood samples
 Insertion Sites
 Subclavian or internal jugular vein
 Location
 Superior vena cava near right atrium or within
right atrium
Central Venous Catheter:
Decrease in CVP
 Decreased venous return (VOLUME!)

Absolute hypovolemia
 Blood loss - Hemorrhage
 Dehydration

Relative hypovolemia
 Shock
 Vasodilation
Decrease in CVP
 Decreased intrathoracic pressure
 Spontaneous inspiration
 Increased ability of the right heart to move
blood
Central Venous Catheter:
Increase in CVP
 Increased venous return
 Hypervolemia
 Volume overload
 Fluids being given faster than the heart can
tolerate
 Increased intrathoracic pressure
 Positive pressure ventilation
 Pneumothorax
Central Venous Catheter:
Increase in CVP
 Decreased ability of the right heart to
move blood – Right heart failure
 Increased pulmonary vascular resistance
 Pulmonary hypertension
 Pulmonary embolism
 Compression around the heart
 Constrictive pericarditis
 Cardiac Tamponade
Central Venous Catheter:
Increase in CVP
 Decreased ability of the right heart to
move blood
 Right ventricular failure
 Myocardial infarction
 Cardiomyopathy
 Left ventricular failure (late change in CVP)
 An increase in CVP leads to a decrease in
blood return to the right heart
Central Venous Catheter:
CVP Reading
 CVP is ideally read at the end of
expiration because...


Spontaneous inspiration causes CVP to fall
Mechanical ventilation causes CVP to rise
Central Venous Catheter:
Complications
 Infection
 Bleeding
 Pneumothorax – greatest hazard
Pulmonary Artery Catheter
 Swan-Ganz Catheter
 Flow-directed, balloon
tipped catheter
PA
 Monitoring heart rate, blood pressure, and CVP often do
not provide accurate or timely data for correct diagnosis
and management of cardiopulmonary problems. Can
monitor the right and left sides of the heart
 The pulmonary artery catheter has a number of variations
however it is
• Typically 110 cm in length
• With 3 lumens (interior channels)
• The exterior of the catheter is marked off in 10 cm
segments used to estimate catheter tip location upon
insertion
Pulmonary Artery Catheter
 Distal lumen lies in the pulmonary artery




Measure pulmonary artery pressures
Aspirate mixed venous samples
Inject medications
Continuous monitoring of SvO2
Swan Ganz
 http://www.youtube.com/watch?v=puXQO
EUENcQ&feature=related
 http://www.youtube.com/watch?v=PjRRPh
Mj0os&feature=related
Pulmonary Artery Catheter
 Balloon
 1.5 cc maximum inflation volume
 Used to help float catheter into place
Pulmonary Artery Catheter
 Thermistor
 Temperature sensing device
 Used during thermodilution CO measurements
 Measures core temperature
Pulmonary Artery Catheter
 Proximal lumen lies in the right ventricle




Measure CVP
Inject medications
Aspirate blood samples
Inject thermal bolus for thermal dilution CO
measurements
Pulmonary Artery Catheter:
Indications
 Hemodynamically
unstable patients
 Complex, acute heart
disease
 Acute, severe
pulmonary disease
 Shock of all types if
severe or prolonged
 Severe, multisystem
trauma or large-area burn
injury
 Major systems
dysfunction undergoing
extensive operative
procedures
Pulmonary Artery Catheter
 Common uses





Measure CVP, PAP, and PCWP
Collect mixed venous blood samples
Monitor mixed venous O2 saturation
Measure cardiac output
Provide cardiac pacing
Pulmonary Artery Catheter:
Insertion
 Insertion: Subclavian
or internal jugular vein
 Superior vena cave
 Right atrium
 Normal pressure:
0-6 mmHg
RA/CVP Pressure
Pulmonary Artery Catheter:
Insertion
 Right ventricle
 Pulmonary Artery
Normal pressure: 20-30 mmHg
0-5
Normal Pressure: 20-30 mmHg
6-15
RV Pressure
Atrial Pressure Monitoring


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a – Atrial contraction
c – Closure of tricuspid valves
X descent – Passive atrial filling
v – Atrial diastole
Y descent – Atrial emptying
Pulmonary Artery Catheter:
Insertion
 “Wedge”
Normal Pressure: 4-12 mmHg
 Location
 Branch of pulmonary
artery
PCWP
 Where it will eventually wedge in a smaller
branch of the pulmonary artery
 The balloon is then deflated and the
catheter stabilized in place
 The balloon remains deflated and the PAP
tracing remains on the monitor at all times
 The balloon is inflated only when the
pulmonary capillary wedge pressure is
being taken
Pulmonary Artery Catheter:
Waveform
• As the pulmonary artery catheter is being inserted, its
movement can be followed on the bedside monitor by
observing various pressure waveforms as the catheter
passes freely from the right atrium to a wedged position
in the pulmonary artery
• when the tip of the catheter reaches the great vessels, a
CVP waveform appears on the monitor
• Right Atrial Pressure (RAP) normal: 0-6 mmHg
When the tip of the catheter passes through
the tricuspid valve into the right ventricle we
see a rapid increase in the height of the
pressure waveform
• Right Ventricular Pressure (RVP) normal:
20-30/0-5 mmHg
• the waveform drops to zero during diastole
• the tricuspid valve opens and blood begins
to flow into the ventricle, causing the
pressure wave to increase gradually
• end-diastolic pressure occurs just before
the upstroke
Entry into the pulmonary artery is recognized by a change
in the diastolic portion of the waveform
• Pulmonary Artery Pressure (PAP) Normal: 20-30/6-15
mmHg mean: 10-20 mmHg
• The waveform is a miniature of the peripheral arterial
waveform, with a dicrotic notch and a gradual diastolic
runoff that does not drop to zero
• This is where mixed venous blood samples are drawn
from. When the catheter wedges in a smaller branch of
the pulmonary artery, the forward flow of the pulmonary
arterial blood is occluded (like a pulmonary embolus)
• Pulmonary Capillary Wedge Pressure (PCWP,
PAOcclusionP) normal: 4-12 mmHg
• The pulmonary artery waveform should return when the
balloon is deflated
Pulmonary Artery Catheter:
Complications
 Infection
 Bleeding
 Pneumothorax
 Pulmonary artery hemorrhage
 Pulmonary infarction
 Air embolism
 Cardiac arrhythmias
Pulmonary Artery Pressure
 Monitor blood moving into the lungs
 Normal: 20-30 mmHg
6-15
 Average: 22/8 mmHg
 Mean: 13 mmHg
Pulmonary Artery Pressure
Decreases
 Volume of blood ejected by the right
ventricle decreases – (“afterload” of the
RV)
 Pulmonary vasculature relaxes or dilates
Pulmonary Artery Pressure
Increases
 Pulmonary blood flow increases
 Pulmonary vascular resistance increases
 Constriction – hypoxemia, acidosis, drugs, diseases
that cause pulmonary hypertension
 Obstruction – pulmonary embolus
 Compression – disease constricting pulmonary
vasculature
Pulmonary Capillary Wedge
Pressure
 Normal: 8 mm hg (4-12 range)
 Monitors blood moving into the left heart.
 Represents the pulmonary venous
drainage back to the left heart.
Inflation of Balloon
PCWP
 PCWP is also referred to as:





Pulmonary artery occlusion pressure (PAOP)
Left atrial pressure
Left side preload
Left ventricular end-diastolic pressure
Left ventricular filling pressure
PCWP
 The PAP diastolic can be used to estimate
PCWP is some situations
 A comparison of PCWP and PAP can be
used to differentiate between cardiac and
non-cardiac pulmonary edema.
 Increased PCWP and PAP = cardiac
 Normal PCWP and Increased PAP =
Non-cardiac
Pulmonary Capillary Wedge
Pressure Decreases

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
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
Right heart failure
Cor pulmonale
Pulmonary embolism
Pulmonary hypertension
Air embolism
Hypovolemia
 PCWP may be normal in the above pulmonary
conditions.
Pulmonary Capillary Wedge
Pressure Increases
 left heart failure
 mitral valve stenosis
 CHF/ pulmonary edema
 high PEEP effects
 hypervolemia
Clinical Assessment
 Right heart failure
CVP PAP – N or Decrease
PCWP – N or Decrease
CO - N or Decrease
Clinical Assessment
 Lung Disorders (PE, PTHN)
 CVP  PAP  PCWP – Normal of Decrease
 CO – Normal, decrease with large PE
Clinical Assessment
 Left Heart Failure
 CVP – Normal, increase as late sign
 PAP  PCWP  CO - Decrease
Clinical Assessment
 Hypovolemia – Everything decreases
 CVP – First and most dramatic sign
 PAP
 PCWP
 CO
Other Values to Know
 Pulse Pressure – 40 mm HG
 Stroke Volume – 60 – 130 ml/beat
 EF – 65 – 75%
 SVR - < 20 mmHg/L/min
 PVR - < 2.5 mmHg/L/min
Clinical Assessment
 Right heart failure
CVP
PAP
PCWP
CO
Pressure Dampening
 When the monitor does not show a sharp
waveform, not dicrotic notch.
 Catheter can be obstructed or kinked.
IABP
 http://www.youtube.com/watch?v=naEaPo
7PPJE&feature=related
Shock
 Inadequate tissue perfusion resulting in a
hypoxic insult and causing widespread
abnormal cell metabolism and membrane
dysfunction.



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
Hypovolemic Shock
Cardiogenic Shock
Septic Shock
Neurogenic Shock
Anaphylactic Shock
Hypovolemic Shock
 A decrease in the effective circulating
blood volume
 Hemorrhage: loss of whole blood
 Non-hemorrhage: loss from the interstitial
space
 Dehydration
 Vomiting, diarrhea, diuresis
 Third space fluid shift
 Burns, trauma, sepsis
Cardiogenic Shock
 Systemic hypoperfusion due to profound
heart failure and/or the ability to meet
metabolic needs.
 End stage of heart disease caused by




MI
Myocarditis
Cardiac tamponade
Severe valve dysfunction
Septic Shock
 Shock associated with any infectious
disease which causes relative
hypovolemia.
 Caused by many infectious agents
 Predisposing factors
 Invasive procedures
 Organ damage
 Immunocompromised
Sepsis
 A severe illness caused by over whelming
infection of the bloodstream by toxinproducing bacteria.
Neurogenic Shock
 Dysfunction of the sympathetic nervous
system resulting in massive peripheral
vasodilation and systemic hypoperfusion.
 Etiology
 Brain or spinal cord trauma
 Spinal anesthesia
 Drugs
Anaphylactic Shock
 Systemic reaction causing circulatory
failure and biochemical abnormalities.
 Etiology





Drugs
Blood products
Foods
Pollens
Venoms
ICU monitoring and equipment
 Chest Tubes
 Tubes inserted into the chest between the lung and ribs
to allow fluid and air to drain from the area surrounding
the lungs. Removing this fluid and air from around the
lungs allows them to more fully expand. An accumulation
of fluid and air in the lung cavity can cause the lung to
collapse. Chest tubes drain into a large plastic container
near the foot of the patient's bed. The patient may have
one or more of these tubes in place. Nurses will monitor
the comatose patient for non-verbal signs of pain.
 http://www.youtube.com/watch?v=y1gaC3yfhvw
ICU monitoring and equipment
 Eye Tape
 Tape used to close the patient's eyes. It is
important that the eyes be kept moist. We
do this naturally when we blink our eyes.
This reflex is lost in the patient who is
unresponsive but has open eyes. To
protect the eyes and to prevent them from
drying out, eye drops may be put into the
eyes and eye tapes may be used to close
them
ICU monitoring and equipment
 Foley Catheter
 This is a tube (catheter) inserted into the
urinary bladder for drainage of urine. This
helps to monitor the patient's fluid status
and kidney function. The urine drains
through the tube into a plastic bag hanging
low by the foot of the bed.
 Note color and amount. Normal urine
output is about 30-40 ml/hr
ICU monitoring and equipment
 GI Tube
 A tube inserted through a surgical opening
into the stomach. It is used to introduce
liquids, food, or medication into the
stomach when the patient is unable to take
these substances by mouth. Set on
intermittent suction, low around -10 to -20
 Must Have a GI tube in place during
mechanical ventilation
ICU monitoring and equipment
 Intracranial Pressure (ICP) Monitor
 A monitoring device to determine the pressure within the
brain. It consists of a small tube (catheter) attached to
the patient's skull by either a ventriculostomy,
subarachnoid bolt or screw and is then connected to a
transducer, which registers the pressure.
 Ventriculostomy is a procedure for measuring
intracranial pressure by placing an ICP monitor within
one of the fluid-filled, hollow chambers of the brain,
called ventricles. These four natural cavities are filled
with cerebrospinal fluid (CSF), which also surrounds the
brain and spinal chord.
ICU monitoring and equipment
 Shunt
 A procedure to draw off excessive fluid in
the brain. A surgically-placed tube running
from the ventricles which deposits fluids
into either the abdominal cavity, heart or
large veins of the neck
 AV shunt used for hemodialysis
EKG REVIEW
 http://www.youtube.com/watch?v=ex1k_M
PF-w4&feature=related
 http://www.youtube.com/watch?v=ecTM2
O940mg&feature=relmfu
 http://www.youtube.com/watch?v=9TRYM
7IdnDY&feature=related