Hemodynamic monitoring in ICU

1. DR.D.RASIKAPRIYA
FIRST YEAR
MD PEADIATRICS

2. PRETEST
 1. Name some invasive measures and noninvasive ways
of hemodynamic monitoring
 2.Name some advanced hemodynamic monitoring
parameters
 3.What test you do before arterial line insertion
 4.Name a site contraindicated for arterial line
 5.Normal mixed venous oxygen saturation
 6. What is oxygen delivery and oxygen consumption
 7.what is passive leg raising test

3. OBJECTIVES
 HEMODYNAMICS
 What is it?
 Why is it important to monitor?
 Whom to include?
 How to measure?
 Its merits and demerits.

4. HEMODYNAMICS- DEFINITION
 the forces which circulate blood through the
body.
 used to describe the intravascular pressure and
flow that occurs when the heart muscle contracts
and pumps blood throughout the body.

5. Hemodynamic Monitoring
 measurement of pressure, flow and oxygenation of blood
within the cardiovascular system.
OR
 Using invasive technology to provide quantitative
information about vascular capacity, blood volume, pump
effectiveness and tissue perfusion.
OR
 measurement and interpretation of biological systems that
describes the performance of cardiovascular system

6. QUESTION???????
 HOW MANY TIMES DOES OUR HEART
BEATS/DAY?

7. PURPOSE OF MONITORING
 Circulatory shock is an important cause of pediatric
morbidity and mortality.
 Early recognition of inadequate tissue perfusion &
oxygenation followed by prompt treatment most important.
 In pediatric circulatory shock, cardiac output (CO) & BP can
be low, normal, or high.
 Physical examination, poorly reflects CO, preload status, or need
for fluid or other hemodynamic interventions.
 BP & HR often do not reflect blood flow

8.  Potential clinical value of 4 advanced hemodynamic
monitoring technologies
 CO monitoring
 Venous oximetry
 Fluid responsiveness
 Lung water

9. DO2 = SaO2 × Hb × CO
After load
Preload SV × HR
Contractility
Blood pressure = SVR × CO
HEMODYNAMIC PHYSIOLOGY

10. Physical Examination
Level of consciousness, activity, or agitation
State of hydration
Peripheral edema
Respiratory pattern
Peripheral perfusion/capillary refill time
Toe-to-core temperature gap
Heart rate and rhythm
Pulse characteristics
Urine output
Hepatomegaly
Jugular venous pressure
Pulmonary and cardiac auscultation

11. METHODS
NON INVASIVE INVASIVE
 NIBP
 ECG
 Chest X ray
 ECHO
 Blood pressure monitoring-ABP
 Central venous pressure monitoring
 Pulmonary artery pressure
monitoring
 Mixed venous oxygen monitoring
 Cardiac output

12. QUESTION???
 EACH VENTRICLE EJECTS - ? ml of blood/beat.

13. NON INVASIVE METHODS
 BLOOD PRESSURE:
INDIRECT ARTERIAL BP MEASUREMENT :
 palpation method (Riva-Rocci)
 auscultatory method
 oscillometric method
 rheographic method
 the phase-shift method
 ultrasonic arterial wall motion detector

15. CONTD..
Flow required across an occlusive cuff
Methods
 Auscultatory
 Oscillometric
Width of the inflatable bladder be 40% of the mid-
circumference of the limb, length should be twice the
width

16. Auscultatory NIBP
Pneumatic cuff inflated to occlude arterial blood flow
As cuff is deflated, audible frequencies (Korotkoff
sounds) are created
First sound = SBP
Last sound (or when muffled) = DBP

17. Auscultatory NIBP
 Errors in measurement:
 Long stethoscope tubing
 Poor hearing in observer
 Calibration errors of sphygmomanometer
 Decreased blood flow in the extremity
 Severe atherosclerosis (unable to occlude)
 Inappropriate cuff size
 Too rapid deflation
 accuracy reduced : low cardiac output, significant
hypotension, hypoperfusion, vasoconstriction, dysrhythmias,
edema.

18. Oscillometric NIBP
 Pneumatic cuff inflated to
occlude arterial blood flow
 Cuff deflated, arterial
pressure pulsations detected
and analyzed
 SBP = rapidly increasing
oscillations
 MAP = maximal point of
oscillations
 DBP = rapidly decreasing
oscillations
 Dina map (device for
indirect noninvasive mean
arterial pressure)

19. Variations in BP by Age
Age Mean BP (mm Hg)
Newborn 73/55(30-60)
1 year 90/55
6 years 95/57(60-100)
10 years 102/62
14 years 120/80
Adult 120/80
Elderly (over 70 years) Diastolic pressure may increase

20. NIBP - Complications
Too frequent inflations
 extremity edema
 nerve paresthesias
 compartment syndrome
Skin irritation

21. ELECTROCARDIOGRAM
 Evaluation of heart rate and rhythm,
ischemia, and conduction defects
 Trend monitor
 Sources of errors:
 Waveform artefact
 Electrocautery (diathermy) is the
main source of electrical
interference
 Muscle activity
 Movement artefact

23. INVASIVE MONITORING
 INVASIVE BLOOD PRESSURE:
 Continuous monitoring of systemic arterial blood
pressure,
 Frequent blood sampling, and
 Withdrawal of blood during exchange transfusions

24. Arterial Blood Pressure
Monitoring Components
 Arterial cannula with a
heparinized saline column
and flushing device
 Transducer
 Amplifier
 Oscilloscope.

25.  Advantages
Providing continuous monitoring,
Providing access for blood sampling
Display of the waveform in addition to the BP value
True heart rate in the presence of dysrhythmias
Allows specific management strategies to be directed
by changes in systolic, diastolic, or pulse pressure,
rather than mean pressure alone.

26. Complications
Bleeding
Thrombosis
Hematoma
Infection
Vascular compromise
Nerve damage
Accidental injection of air
or thrombus
Digital necrosis
Arteriovenous fistulae
Carpal tunnel syndrome

27.  Factors that increase the risk of arterial catheter
thrombosis:
 Larger catheter-to-vessel ratio
 Prolonged cannulation
 Multiple cannulation attempts
 Presence of peripheral vascular disease
 Venous and arterial femoral Catheterization in single
extremity
 Younger age
 Thrombogenic conditions

28.  Sources of error
 Inaccurate transducer level.
 Recordings should be made with the child in the supine
position and the transducer at the level of the mid-chest
or mid-axillary line. ( 7.5 mm Hg for each 10 cm change
in position)
 Zeroing
 Careful flushing of the catheter and pressure tubing to
remove blood and air bubbles and choosing the
shortest, stiffest, and largest catheter.

29. SVO2 60-75%
Stroke volume 50-100 mL
Stroke index 25-45 mL/M2
Cardiac output 4-8 L/min
Cardiac index 2.5-4.0 L/min/M2
MAP 60-100 mm Hg
CVP 2-6 mm Hg
PAP systolic 20-30 mm Hg
PAP diastolic 5-15 mm Hg
PAOP (wedge) 8-12 mm Hg
SVR 900-1300 dynes.sec.cm-5

30. Central Venous Pressure Monitoring
Indications:
 assessment of right heart filling pressure
 monitoring of large fluid shifts from the intravascular to
the extravascular space and vice versa
 Infusion of vasoactive substances
 infusion of hyperosmolar fluids and/or irritants

31. Central Venous Pressure Monitoring
Secure IV access in critically ill children who may
require large-volume fluid infusions or parenteral
nutrition
Monitoring cvp-indirect measurement of cardiac
preload
Provides access for blood sampling for measurement
of mixed venous saturation.
CVP- 0 – 6 mmHg

34. Information Obtained from CVP
Waveforms
Loss of A wave and irregular rhythm = suggests atrial
fibrillation or flutter
Cannon A waves = junctional rhythm, complete heart
block, ventricular arrhythmias, TS, RVH, PS, Pulm
HTN

35. Complications
Central line insertion Indwelling catheters
 Arterial (carotid, subclavian, femoral)
puncture
 Local hematoma
 Air embolism
 Catheter malposition (to neck tissue,
mediastinal, pericardial, or pleural
cavities)
 Pneumothorax
 Hemothorax
 Brachial plexus injury
 Dysrhythmias
 Infection
 Local hematoma
 Extravasation
 Vascular thrombosis
 Embolus (clot or air)
 Intracardiac thrombus
 Superior vena cava syndrome
 Chylothorax
 Local nerve damage

36. PULMONARY ARTERY CATHETERS
Septic shock unresponsive to fluid resuscitation and
low-dose vasopressor support,
Refractory shock following severe burn injuries,
Children with CHD, multiple organ failure, and
respiratory failure requiring high mean airway
pressures

39. CAPABILITIES OF PAC
 determination of CVP,
 pulmonary artery pressure (PAP), and
 pulmonary artery occlusion pressure (PAOP), also
referred to as pulmonary capillary wedge pressure (Pw)

40. PULMONARY ARTERY PRESSURE
MONITORING
Assess fluid status
CO
tissue oxygenation (Svo2),
oxygen delivery (Do2) and consumption (Vo2),
pulmonary vascular resistance (PVR) and systemic
vascular resistance (SVR)

41. Complications of PAC Placement
 Arrhythmias, complete heart block
 Endobronchial hemorrhage
 Pulmonary infarction
 Catheter knotting and entrapment
 Valvular damage
 Thrombocytopenia, thrombus formation
 Incorrect placement, balloon rupture

42. Cardiac Output Monitoring
 CO = HR x SV
 3.5 – 5 L/min/m2
 Preload, afterload, HR, contractility
 determinant of systemic oxygen delivery
 shock, multiple organ failure, unexplained
hypotension, severe cardiac disease, significant
cardiopulmonary interactions.

43. Measures of adequate o2 supply
Mixed venous o2 saturation
blood lactate
Tissue CO2 tonometry
NIRS (Near Infrared Spectroscopy)

44. BLOOD LACTATE
 Tissue dysoxia in states of mitochondrial dysfunction associated
with sepsis, poisoning, and various inborn errors of metabolism
 Accelerated anerobic glycolysis
 Lactate-containing replacement fluids during high-volume
hemofiltration
 Acute hyperventilation can elevate blood lactate levels, perhaps
secondary to increased splanchnic release of lactate during
hyperventilation

45. Tissue PCO2 Monitoring Using Tonometry
 Designed to measure tissue hypoperfusion
 Involves placement of a CO2-permeable balloon
adjacent to a mucosal surface
 Tissue hypoperfusion- increased intracellular CO2
 Gastric tonometry: inconsistent results
 Sublingual tonometry, suggested during early phases
of resuscitation

47. Near Infrared Spectroscopy
 Monitoring device for patients with potential
hemodynamic instability or deficits in regional
(primarily cerebral) perfusion
 Deoxy Hb absorbs light in the range of 760 nm or
lower, whereas both deoxy and oxy Hb absorb light at
~800 nm

49. TAKE HOME MESSAGE
 Multiple different methods of hemodynamic
monitoring
Keys to success
 Know when to use which method
 Technical skills for device placement
 Know how to interpret the data
 Remember the limitations of the technology

50. THANK U