Oxygen therapy

1. OXYGEN THERAPY
SURG LT CDR IA AKUBO
INTENSIVE CARE UNIT
NNRH OJO
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2. OUTLINE
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Introduction
Pathway of O2
Indication of O2 therapy
O2 Delivery systems
Monitoring of O2 therapy
Complications of O2 therapy
Conclusion
References
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3. INTRODUCTION
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History:
Joseph Priestly, an English Chemist in 1774
discoverd O2.
He prepared O2 by heating mercury oxide with a
burning glass.
He found that oxygen does not dissolve in water
and it made conbustion stronger.
Antonie-Laurent Lavoiser Clarified use of O2
for combustion & respiration with elimination
of CO2 & H2O.
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4. INTRODUCTION
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Definition:
Oxygen therapy is the administration of
oxygen at concentrations greater than
that in ambient air with the intent of
treating or preventing the symptoms
and manifestations of hypoxia.1
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5. INTRODUCTION
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Properties of O2:
O2 is tasteless, colourless & odourless gas.
Make 21% of atmospheric air.
Boiling point -183°C
Melting point -218°C
Critical point -118°C
Relative Density -1.105
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6. INTRODUCTION
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Sources Of Oxygen.
Ambient air
Oxygen Manifold (Wall oxygen)
Oxygen cylinders
Oxygen Concentrators
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7. INTRODUCTION
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Storage:
Liquid form
Pressurized cylinders
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8. Pressurized cylinders
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9. PATHWAY OF O2
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O2 Cascade
O2 Flux
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10. PATHWAY OF O2
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Partial pressure of oxygen in:
Dry atmospheric air; 21KPa (160mmHg)
Humid tracheal air; 19.8KPa (150mmHg)
Alveolar air; 14KPa (106mmHg)
Arterial blood; 13.3KPa (100mmHg)
Capillary blood; 6 – 7KPa (45-55mmHg)
Mitochondria; 1 – 5KPa (7.5-40mmHg)
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11. PATHWAY OF O2
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O2 Flux = Amount of delivered/ unit time
CO*Arterial O2 Content
CO*{(10*Hb*SaO2*1.34) + (10*PaO2*0.0225)
Normal Range-
800-1200ml/min
500-700ml/min/m2
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12. INDICATION FOR O2
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Hypoxia
Respiratory Failure
Type I
Type II
Cardiac
CCF
MI
Dehydration
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13. INDICATION FOR O2
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Hypoxia
Demand
Seizures
Sepsis/fever
Toxicity
Cyanide toxicity
Haemic
Anaemia
Carboxyhaemoglobinemia, Methemoglobinemia
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14. INDICATION FOR O2
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Clinical Indicators:
dyspnoea, tachypnoea, bradypnoea, apnoea
pallor, cyanosis
lethargy or restlessness
use of accessory muscles: nasal flaring,
intercostal or sternal recession, tracheal tug
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15. O2 DELIVERY SYSTEM
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Non Invasive
Variable performance equipment
Nasal cannula/prongs
Face mask
Non reservoir mask
Reservoir mask
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16. RESERVOIR MASK
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17. RESERVOIR MASK
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18. O2 DELIVERY SYSTEM
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Non Invasive
Fixed performance equipment
Air Mask Valve system
Air entrain venturi mask
Air entrain Nebulizer
High flow air oxygen system
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19. AIR ENTRAIN VENTURI MASK
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20. AIR ENTRAIN VENTURI MASK
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21. O2 Delivery systems
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Invasive
Cricothyrotomy
Endotrachial tube
Trachiostomy tube
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22. O2 Delivery systems
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Mechanical ventilation:
Anaesthetic Machine
Ventilators
Heart Lung Machine
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23. VENTILATOR
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24. MONITORING OF O2 THERAPY
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Clinical
Pulse
Skin colour
Respiratory findings
Laboratory
Pulse oxymetry
ABG 24

25. ABG
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26. NORMAL ABG VALUES
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PH: 7.36-7.44
PaCO2: 35-45mmHg /4.6-6.0KPa
PaO2: 75-105mmHg / 10-14KPa
HCO3
-: 24-28mEq/L (20-26mmol/L)
NOTE:
1mmHg-1Torr
1KPa-7.5mmHg
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27. MULTIPARAMETER DISPLAY MONITOR
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28. MONITORING OF O2 THERAPY
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29. COMPLICATION OF O2 THERAPY
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CNS Toxicity
Absorption atelectesis
Pulmonary toxicity
Fire Hazard
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30. REFERENCES
1.
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4.
Fulmer JD, Snider GL. ACCP-NHLBI National
Conference on Oxygen Therapy.
Update in anaesthesia Basic sciences:
Volume 24, Number 2 December 2008
A-Z in Anaesthesia & Intensive care, An
encyclopaedia of principles & practice, 3rd
edition by S M Yentis, N P Hirsch, G B Smith.
Textbook of Anaesthesia for postgraduates
by T K Agasti, 1st edition: 2011
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31. REFERENCES
5. Clinical Anaesthesiology: G. E. Morgan Jr, M. S.
Mikhail, M. J. Murray; 4th edition
6. Text book of Anaesthesia: A. R. Aitkinhead, G.
Smith, D. J. Rowbothan; 5th edition
7. Anaesthesia secrets: J. Duke MD; 4th edition
8. Wikipedia, the free encyclopedia.mht
9. NNRH Ojo Photo library.
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