Hemodynamic

Monitoring

HEMODYNAMIC MONITORING

Hemo

Blood

Dynamics

Movement

Hemo

Dynamics

Movement

of blood

flow

HAEMODYNAMICS

Systole Diastole

100-140 mm Hg

60-90mm Hg

METHODS OF HAEMODYNAMIC

MONITORING

• Non invasive hemodynamic assessment

• Arterial Blood Pressure

Non-invasive

Direct arterial pressure measurement

• Central Venous Pressure

• The Pulmonary Artery Catheter

• Cardiac Output Measurement

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

• Take vital signs

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

• Precordium

Inspect anterior chest for

heaves and an increase in

visible pulsations

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

• Palpate the PMI

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

• Ausultate the

aortic, pulmonic,

second

pulmonic, mitral

and tricuspid

areas of the

precordium

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

• Peripheral vascular

• Inspect and palpate the skin for colour, texture,

moisture and turgor

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

• Palpate the peripheral pulses and check nail

bed capillary refill

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

• Inspect the neck for jugular venous distension

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

• Auscultate and palpate the carotid arteries

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

• Assess for hepato jugular reflux

ARTERIAL BP MONITORING

Indirect methods

Traditional method of cuff and mercury

manometer (Auscultation from the Latin for

listening)

NIBP machine or oscillometry

Direct methods

Intra-arterial catheter / transducer system

Traditional method of cuff and

mercury manometer

OSCILLOMETRIC METHODS

• With an electronic pressure

sensor (transducer) fitted in

to detect blood flow,

• The pressure sensor is a

calibrated electronic device

with a numerical readout of

blood pressure.

Advantages of non invasive BP

monitoring

• Simpler and quicker than invasive

measurements

• Require less expertise in fitting

• Have virtually no complications

Limitations of Non-invasive Blood

Pressure Monitoring

• Cuff must be placed correctly and must be appropriately sized

– Auscultatory method is very inaccurate

– Korotkoff sounds difficult to hear

– Significant underestimation in low-flow (i.e. shock) states

• Oscillometric measurements also commonly inaccurate (> 5

mm Hg off directly recorded pressures)

ARTERIAL LINE

BPMONITORING

Arterial line

Uses

• Record blood pressure

(systolic, diastolic, mean and

pulse pressure)

• Arterial blood sampling

Arterial line BP monitoring

Specific indications

• Labile blood pressure

• Anticipation of haemodynamic

instability

• Titration of vasoactive drugs

• Frequent blood sampling

• Morbid obesity (unable to fit an

appropriately sized NIBP cuff)

CONTRAINDICATIONS

Absolute contraindications

• Absent pulse

• Thromboangiitis obliterans (Buerger

disease)

• Full-thickness burns over the

cannulation site

• Inadequate circulation to the extremity

• Raynaud syndrome

CONTRAINDICATIONS

Relative contraindications

• Anticoagulation

• Atherosclerosis

• Coagulopathy

• Inadequate collateral flow

• Infection at the cannulation site

• Partial-thickness burn at the cannulation

site

• Previous surgery in the area

• Synthetic vascular graft

Site selection

• Radial artery

• Brachial artery.

• Dorsalis pedis artery.

• Femoral artery

Arterial BP monitoring system

• An intravascular catheter.

• A fluid-filled electro-mechanic monitoring system

containing tubing, pressure transducer, and flush

system.

• A monitor containing an amplifier to convert the small

electronic signal generated by the transducer to a

waveform that is displayed on a screen

Arterial BP monitoring system

Arterial cannula

• A short, narrow, parallel

sided cannula made of

polyurethane or Teflon™

• Larger gauge cannula

increase the risk of

thrombosis, smaller

cannula cause damping

of the signal.

Fluid filled tubing

Fluid filled tubing

• This is attached to the arterial cannula, and provides a

column of non compressible, bubble free fluid between

the arterial blood and the pressure transducer for

hydraulic coupling

• This tubing should be colour coded with red or clearly

labelled.

• A 3way tap is incorporated to allow the system to be

zeroed and blood samples to be take

Transducer

Converting the

pressure

waveform into

an electrical

signal

Infusion/flushing system

• A bag of either plain 0.9% saline

or heparinised 0.9% saline is

pressurized to 300mmHg

• This allows a slow infusion of

fluid at a rate of about 2-4ml/hour

to maintain the patency of the

cannula.

• Signal processor, amplifier and display

Arterial line monitoring system

• Tape

• An arm board or towel roll

• Opsite or Tegaderm cover dressing

• Local anesthetic (1% or 2% lidocaine ,lidocaine cream)

• Suture material for femoral arterial line placement (2.0 silk)

• Scissors

• Monitor cable for transducing arterial waveform.

• Antiseptic solution

Articles

Technique of insertion

• Ensure there is an adequate pulse in the radial

artery prior to attempting the procedure.

Allen test

• To assess collateral perfusion

• The test is performed by asking the

patient to clench their hand. The ulnar and

radial arteries are occluded with digital

pressure.

• The hand is unclenched and pressure over

the ulnar artery is released. If there is

good collateral perfusion, the palm should

flush in less than 6 seconds.

PREPARATION

• Prepare an area over the radial artery about 4-5

cm proximal to the wrist, and cover with the

drape provided.

• Anesthetizing the area over the artery with

lidocaine.

PROCEDURE

• Palpate the artery with your

non-dominant hand

• Use the large needle to

advance through the skin at

a 30 degree angle.

• When the artery is entered,

a pulsatile flow of blood

will be seen

PROCEDURE

• Once in the artery, advance the guide wire through the needle, and remove

the needle, always making sure to be holding on to the guide wire

• Place the 12 cm catheter over the guide wire, and advance until the hub is

up to the skin.

• Remove the guide wire, and connect the catheter to a stopcock for

measuring.

• See if an arterial tracing is obtained.

• Suture the sides of the catheter to the skin to ensure it doesn't fall out.

Click here arterial line insertion

• The transducer has to sit in a “transducer holder” – this is the white

plastic plate that screws onto the rolling pole that holds the whole setup.

• The transducer has to be levelled correctly-to make sure that it’s at the

fourth intercostal space, at the mid-axillary line (Phlebostatic axis)

• Make sure there’s no air in the line before you hook it up to the patient –

use the flusher to clear bubbles out of the tubing.

• Zero the line to atmospheric pressure properly

• Choose a screen scale that lets you see the waveform clearly.

Transducer - A couple of things to remember

• To ensure accuracy of readings

• Flush the device & turn it off to patient but open to

atmosphere

• These exert pressure on transducer

• This pressure is called zero

• Zero once per shift or if values are questionable

• Ensure flush bag is pumped up

Zeroing

COMPLICATIONS

• Haemorrhage may occur if there are leaks in the system.

Connections must be tightly secured and the giving set and line

closely observed..

• Emboli. Air or thrombo emboli may occur.

Care should be taken to aspirate air bubbles

• Accidental drug injection may cause severe, irreversible damage to

the hand.

-No drugs should be injected via an arterial line

- The line should be labelled (in red) to reduce the likelihood of this

occurring

COMPLICATIONS

• Arterial vasospasm

• Partial occlusion due to large cannula width, multiple attempts at

insertion and long duration of use

• Permanent total occlusion

• Sepsis or bacteraemia secondary to infected radial arterial lines is

very rare (0.13%);

-local infection is more common.

-if the area looks inflamed the line site should be changed.

Never inject anything into an arterial

cannula or arterial line

• –Concentration of a drug into

the tissues served by the

cannulated artery can result in

cell death

• –Skin necrosis, severe

gangrene, limb ischemia,

amputation & permanent

disabilities

Arterial pressure waveform

• Once inserted, an arterial

waveform trace should be

displayed at all times

• This confirms that the invasive

arterial BP monitoring is set

up correctly, and minimizes

problems.

ARTERIAL WAVE FORM

Is it accurate?

• Now we know how the arterial pressure monitoring

system works, we need to be able to decide whether or not

the trace (and BP in numerical format) is accurate.

• Failure to notice this may lead to unnecessary, or

missed treatments for our patients.

• There are 2 main abnormal tracing problems that can

occur once the monitor gain is set correctly.

Sources of error

• Failure of any one of the components in system

• Transducer position

– pressure displayed is pressure relative to position of transducer

– in order to reflect blood pressure accurately transducer should be

at level of heart. Over-reading will occur if transducer too low

and under-reading if transducer too high

– transducer must be zeroed to atmospheric pressure

• Damping.

• Dampened trace

Dampened: wide, flattened tracing

• Dampening occurs due to:

– air bubbles

– overly compliant, distensible tubing

– catheter kinks

– clots

– low flush bag pressure or no fluid in the flush bag

– Improper scaling

– Severe hypotension if everything else is ruled out

• Resonant trace

Resonant: ‘spiked’ tracing

• Resonance occurs due to:

– long tubing

– overly stiff, non-compliant tubing

– increased vascular resistance

– non-fully opened stopcock valve

• Arterial lines measure systolic BP

approximately 5 mmHg higher and

the diastolic BP approximately 8

mmHg lower compared to non-

invasive BP (NIBP) measurement

Comparison with non-

invasive BP

Advantages of IBP measurement

• Continuous blood pressure recording

• Accurate blood pressure recording even

when patients are profoundly hypotensive

vs NIBP which is difficult or inaccurate

• Real time Visual Display

Disadvantages of IBP measurement

• Potential complications

• Skilled technique reqd

• Expensive

NURSE’S RESPONSIBILITY

CVP MONITORING

CENTRAL VENOUS PRESSURE

Right AtriumThe presure of the blood

within the right atrium is

the central venous pressure

The normal value

for CVP ranges

from 8-12cm of

H2O

NON INVASIVE HAEMODYNAMIC

ASSESSMENT

CENTRAL LINE INSERTION

INDICATIONS

• CVP Monitoring

• Rapid infusion

• Infusion of hypertonic solutions and

medications that could damage veins

• Serial venous blood assessment

Articles required for CVP insertion

Methods of CVP Monitoring

Manometers

Transducers

Manometer Method

Line up the manometer with phlebostatic

axis

Move the manometer scale up and down

the bubble to be aligned with zero on the

scale. This is referred as zeroing of

manometer

Turn the three way tap off to the

patient and open to the manometer

Open the IV fluid bag and slowly fill

the manometer to a level higher than the

expected CVP

Measuring CVP using manometer

Turn off the flow from the fluid bag and

open the three way tap from the

manometer to the patient

The fluid level inside the manometer

should fall until the gravity equals the

pressure in the central veins

When the fluid stops falling the CVP

measurement can be read. If the fluid

moves with the patients breathing, read

the measurement from the lower number

Turn the tap off to the manometer

Measuring CVP using manometer

CVP Monitor with transducer and

monitor

Precautions while handling central line

• Hand hygiene before and after any manipulation

of vascular access devices or catheter

• An aseptic technique

• Standard precautions.

• Sterile disposable transducers, pressure tubing

and line are replaced at 96 hour intervals

PROCEDURE FOR CVP MONITORING

• Obtain verbal consent

• Position patient supine or semi recumbent to 30-45 degree elevation

• Prime pressure tubing with Sodium chloride 0.9%, close connection

• Check flushing mechanism

• Apply the pressure bag and inflate to 300mmHg

• Connect to monitor transducer cable

• Calibrate zero and level the transducer to the phlebostatic axis

• Attach extension tubing to central venous catheter, open fluid path,

and adjust rate

• Close the stopcock to the patient and open to air and read the display

monitor at end of expiration

• Reopen stopcock to patient; recommence intravenous transfusion at

prescribed rate

• Record the result

• Report abnormal readings or change in trends

• Monitor insertion site for infection, bleeding and disconnection. See

PROCEDURE FOR CVP MONITORING

Typical CVP waveform

Three peaks

• a- atrial contraction

• c- closure of tricuspid valve

• v-ventricular diastole

Two descents

• x – atrial relaxation

• y- tricuspid valve reopening

• Click here CVP wave form

Typical CVP waveform

• CVP is elevated by :

– overhydration which increases venous return

– heart failure or PA stenosis which limit venous

outflow and lead to venous congestion

– positive pressure breathing, straining,

• CVP decreases with:

– hypovolemic shock from hemorrhage, fluid shift,

dehydration

– Negative pressure breathing

COMPLICATIONS

• Pneumothorax

• Haemothorax

• damage to vein or adjacent structures

• vein thrombosis or thrombophlebitis

• infection

• cardiac arrhythmias

• haemorrhage

• air embolism

NURSE’S RESPONSIBILITY

PULMONARY ARTERY

CATHETER

• Swan and Santa Monica Bay sailboats

discovered swanz ganz catheter(Triple lumen

catheter)

• Measures CVP, PAP, PAOP, Cardiac Index and

SVO 2

Indications for Pulmonary Artery

Catheterization

• Identification of the type of shock

Cardiogenic (acute MI)

Hypovolemic (hemorrhagic)

Obstructive (PE, cardiac tamponade)

Distributive (septic)

• Monitoring the effectiveness of therapy

PA catheter

Complications of Pulmonary Artery

Catheterization

• General central line complications

• Pneumothorax

• Arterial injury

• Infection

• Embolization

• Inability to place PAC into PA

• Arrhythmias (heart block)

• Pulmonary artery rupture

NORMAL HEMODYNAMIC VALUES

PARAMETERS NORMAL VALUE

Stroke volume 50-100 mL

Cardiac output 4-8 L/min

Cardiac index 2.5-4.0 L/min/M 2

MAP MAP 60-100 mm Hg

CVP 2-6 mm Hg

PAP systolic 20-30 mm Hg

PAP diastolic 5-15 mm Hg

PAWP (wedge) 8-12 mm Hg

Colour code for various lines

CARDIAC OUTPUT MONITORING

Thermodilution (pulmonary

artery catheter)

• Boluses of ice-cold fluid are

injected into the pulmonary artery

and the change in temperature

detected in the blood of the

pulmonary artery

Any doubts?