Oxygen therapy provides oxygen at concentrations greater than room air to treat hypoxia. There are several methods of oxygen delivery including nasal cannulas, simple masks, partial and non-rebreathing masks, and high flow devices. The type of delivery system used depends on factors like the needed oxygen concentration, flow rate, patient comfort and cost effectiveness. Proper assessment is important to determine if a patient requires oxygen therapy.

1. OXYGEN THERAPY
Dr.Gagan

2. Oxygen:
• Colourless
• Odourless
• Tasteless
• Transparent gas
• Slightly heavier than air
• Constitutes 20-21% of atmospheric air
• Essential for life

3. What is O2 Therapy ?
Oxygen therapy is the administration
of oxygen at concentrations greater
than that in room air to treat or prevent
hypoxia.

4. Oxygen is available to us
• Medical grade oxygen (99% or 99.5% pure) is
manufactured by fractional distillation of liquid air.
• Oxygen can be stored as compressed gas at room
temperature or as liquid when refrigerated.
• Oxygen cylinder
• Delivery system : Hose drops, Gas columns,
Articulating arms
E-cylinder
capacity
H-cylinder
Capacity
Pressure
(psig at 20oC)
Color PIN
index
625-700 liters 6000-8000
liters
1800-2000 Black body with
white shoulder
2, 5

5. Anoxia
No oxygen availability in tissues
Hypoxia
Lack of oxygen availability in
tissues
Hypoxemia
Lack of oxygen in the blood

6. 6
Indications for Oxygen Therapy
• Hypoxemia
– Inadequate amount of oxygen in the blood
– SPO2 < 90%
– PaO2 < 60 mmHg
• Excessive work of breathing
• Excessive myocardial workload

7. 7
Causes of Hypoxemia
• Shunt
• Hypoventilation
– As carbon dioxide increases oxygen falls
• V/Q mismatching (ventilation/perfusion)
– Pneumonia
– Pulmonary edema
– ARDS
• Increased diffusion gradient
– asbestosis
– Early pulmonary edema

8. Hypoxia

9. Types of hypoxia
• Hypoxic hypoxia – PaO2↓
• Anaemic hypoxia – O2 content ↓, PaO2 normal
• Stagnant hypoxia
• Histotoxic hypoxia

10. Hypoxic hypoxia
• Causes
– O2 poor air, hypoxic gas mixture
– High altitude
– Hypoventilation
– Shunts – Septal defects
– Diffusion defects - pneumonia, lobar collapse

11. Anaemic hypoxia
• Oxygen carrying capacity of blood is
decreased.
– Anemia :↓ haemoglobin
– Altered haemoglobin
• CO poisoning
• meth / sulph-haemoglobin

12. Stagnant hypoxia
• Inadequate tissue perfusion
• Generalized:
- Hypovolemia
- Mitral stenosis
- Constrictive pericerditis
- Myocardial ischaemia
• Localized hypo perfusion:
- Arterial obstruction, thrombus,
oedema

13. Histotoxic hypoxia
• Cells can not utilize the oxygen .
• Electron transfer system of cytochrome
oxidase is paralysed.
• e.g.
– cyanide poisoning

14. Benefit of O2 therapy in Hypoxia
Hypoxic hypoxia + + +
Anaemic hypoxia +
Stagnant hypoxia +
Histotoxic hypoxia -

16. Effects of hypoxia
• Acute hypoxia :
- Restlessness
- Disorientation, confusion
- In-coordination, Impaired judgment
- Hyperventilation air hunger
-Circulatory changes (tachycardiabrady )
• Chronic hypoxia :
- fatigue, drowsiness, ↓ work capacity
- inattentiveness ,apathy, delayed reaction time

17. Oxygen Therapy

18. Assessment of need
• Presence of clinical indicators
• Measurement of inadequate oxygen saturations
– by invasive or noninvasive methods,
• Arterial blood gas
• Pulse oximetry
Errors in pulse oximetry
• Artificial fingernails
• Dark pigmentation
• Electrical interference
• Intravenous dyes
• Movement
• Nail Polish
• Pulsatile venous system
• Radiated light

19. Types of Oxygen Therapy
• Giving Oxygen more
than 21% at ambient
atm pressure
• Giving Oxygen more
than 21% at high atm
pressure ( >1 atm)
Orthobaric Hyperbaric

20. Three clinical goals of O2 therapy
1. Treat hypoxia
2. Decrease work of breathing
3. Decrease myocardial Work

21. Oxygen therapy
1. Correcting Hypoxemia
• By raising Alveolar & Blood levels of Oxygen
• Easiest objective to measure
2. Decreasing symptoms of Hypoxemia
• Supplemental O2 can help relieve symptoms of
hypoxia
–Lessen dyspnoea/work of breathing
–Improve mental function

22. 3. Minimizing Cardiopulmonary workload
• Cardiopulmonary system will compensate for Hypoxemia
by:
– Increasing ventilation to get more O2 in the lungs & to the Blood
– Increased work of breathing
– Increasing Cardiac Output to get more oxygenated blood to tissues
– Hard on the heart, especially if diseased
• Hypoxia causes Pulmonary vasoconstritcion & Pulmonary
Hypertension
– These cause an increased workload on the right side of heart
– Over time the right heart will become more muscular & then
eventually fail (Cor Pulmonale)

23. • Supplemental o2 can relieve hypoxemia & relieve
pulmonary vasoconstriction & Hypertension,
reducing right ventricular workload!!
• Minimal acceptable saturation for post surgical
patients who are cared for in non critical setup is
92%

24. FACTORS THAT DETERMINE WHICH SYSTEM
TO USE
1. Patient comfort / acceptance
2. The level of FiO2 that is needed
3. The requirement that the FiO2 be controlled
within a certain range
4. The level of humidification and /or
nebulization
5. Minimal resistance to breathing
6. Efficient & economical use of oxygen

25. Orthobaric Oxygen therapy

26. EQUIPMENT

27. LOW FLOW DEVICES
HIGH FLOW DEVICES

28. LOW FLOW
OXYGEN DELIVERY
DEVICES

30. NASAL CANNULA
HOW TO USE?
 disposable.
plastic devise with two protruding
prongs for insertion into the nostrils,
connected to an oxygen source.

31. - The standard nasal cannula delivers an
inspiratory oxygen fraction (FIO2) of 24-44% at
supply flows ranging from 1-6 L·min-1.
- The formula is FIO2 = 20% + (4 × oxygen litre
flow). The FIO2 is influenced by breath rate,
tidal volume and pathophysiology.
- The slower the inspiratory flow the higher the
FIO2.

32. Delivers 24 to 44% oxygen at 1 to 6 L/min
• 1 = 24 %
• 2 = 28 %
• 3 = 32 %
• 4 = 36 %
• 5 = 40 %
• 6 = 44 %

33. FACTS
ADVANTAGES
Patients are able
to talk and eat with
oxygen in place
Easily used in
home setting
DISADVANTAGES
may cause irritation
to the nasal and
pharyngeal mucosa
if oxygen flow rates
are above 4
liters/minute
Variable FIO2

35. SIMPLE OXYGEN MASK
Simple mask is made of clear, flexible , plastic
or rubber that can be molded to fit the face.
 It is held to the head with elastic bands.
Some have a metal clip that can be bent over
the bridge of the nose for a comfortable fit

36. O2 inlet
Exhalation
ports
• Open ports for
exhaled gas
• Air entrained through
ports if O2 flow
through does not
meet peak inspiratory
flow

37. • 5 – 10 liters per minute
• < 5 liters will not flush CO2
from mask
• 40 – 60% FIO2 approximately
depending on the pattern of
breathing.

38. FACTS
ADVANTAGES
• Can provide increased
delivery of oxygen for
short period of time
• The face mask is
indicated in patients
with nasal irritation or
epistaxis.
• It is also useful for
patients who are strictly
mouth breathers.
DISADVANTAGES
-Tight seal required to deliver
higher concentration
- Difficult to keep mask in
position over nose and mouth
-Potential for skin breakdown
due(pressure, moisture)
- Uncomfortable for pt while
eating or talking.
- Obtrusive, uncomfortable
and confining.
- It muffles communication,
obstructs coughing.

40. PARTIAL REBREATHING MASK
• Mask is a simple mask with a reservoir bag.
• Same as the Non re-breathing bag
but..without a one way valve.
• Low flow, medium concentration
• 50 – 70%
• 8 – 12 liters per minute
• Bag should remain at least 1/3 full during
inspiration
• Allow the mixture or oxygen and carbon
dioxide in the mask.

41. Partial Rebreather mask
Exhalation
ports
O2
Reservoir
• O2 directed into
reservoir
• Insp: draw gas from bag
& room air
• Exp: first 1/3 of exhaled
gas goes into bag (dead
space)
• Dead space gas mixes
with ‘new’ O2 going into
bag
• Deliver ~60% O2

42. FACTS
ADVANTAGES
- Can inhale room
air through
openings in mask if
oxygen supply is
briefly interrupted.
- Not as drying to
mucous
membranes
DISADVANTAGES
- Requires tight
seal
- Eating and
talking difficult,
uncomfortable
-

44. NON REBREATHING MASK
the one-way valve closes and all of the expired air is
deposited into the atmosphere, not the reservoir
bag.
This mask provides the highest concentration of oxygen
(95-100%) at a flow rate 8-15 L/min.
It is similar to the partial rebreather mask except
two one-way valves prevent conservation of
exhaled air.

45. Non-Rebreathing Mask
• Valve prevents exhaled
gas flow into reservoir
bag
• Valve over exhalation
ports prevents air
entrainment
• Delivers ~100% O2, if
bag does not
completely collapse
during inhalation
O2
Reservoir
One-way valves

46. Non-Rebreathing system
Reservoir
Gas source
Room air
Expiratory
gas
To patient
One way valves

47. FACTS
ADVANTAGES
Delivers the highest
possible oxygen
concentration
Suitable for pt breathing
spontaneous with sever
hypoxemia
DISADVANTAGES
- Impractical for long term
Therapy
- Malfunction can cause
CO2 buildup
-- suffocation
 Expensive
 Feeling of suffocation
 Uncomfortable

48. Estimating FiO2
O2 Flow rate FiO2 O2 Flow rate FiO2 O2 Flow rate FiO2
Nasal cannula Oxygen mask Mask with reservoir
1 0.24 5-6 0.4 6 0.6
2 0.28 6-7 0.5 7 0.7
3 0.32 7-8 0.6 8 0.8
4 0.36 9 0.80+
5 0.4 10 0.80+
6 0.44

49. HIGH FLOW
DELIVERY DEVICES
Or
FIXED
DELIVERY SYSTEMS

50. AIR ENTRAINMENT DEVICES
• High flow device (o2 concentration)
• Entrains air through side ports to achieve
high flows
• Variable entrainment ports and/or jets
adjust FIO2
• Air Entrainment or Venti Masks
• Manufacturer recommends liter flows for
each FIO2

51. The Venturi System
Room air dilutes the oxygen entering
the tubing to a certain concentration
The amount of air drawn in is
determined by the size of the orifice
(jet adapter).
 Applying the Bernoulli principle

52. VENTURI MASK

54. How does it work?
exhaled gas
oxygen
room air

55. Oxygen from 24 - 50%
At liters flow of 4 to 15 L/min.
The mask is so constructed that there is a
constant flow of room air blended with a fixed
concentration of oxygen
Is designed with wide- bore tubing and
various color - coded jet adapters.
Each color code corresponds to a precise
It is high flow concentration of oxygen.
Oxygen concentration and a specific liter flow.

57. Color FiO2 O2 Flow
Blue 24% 2 L/min
White 28% 4 L/min
Orange 31% 6 L/min
Yellow 35% 8 L/min
Red 40% 10 L/min
Green 60% 15 L/min
Venturi valve

58. FACTS
ADVANTAGES
Delivers most
precise oxygen
concentration
Doesn’t dry
mucous membranes
(humidity)
DISADVANTAGES
uncomfortable
Risk for skin irritation
produce respiratory
depression in COPD
patient with high
oxygen concentration
50%

59. TRACHEOSTOMY COLLAR
Directed into trachea
Is indicated for chronic o2 therapy need
O2 flow rate 8 to 10L
Provides accurate FIO2
Provides good humidity.
Comfortable ,more efficient
Less expensive

62. FACTS
ADVANTAGES
• Delivers high
concentrations of oxygen
directly to the lungs.
• Stable and not moved
when the patient is moved
or cleaned.
• Maintains saturation
levels.
DISADVANTAGES
• Viscosity of secretions
• Clinical status
• Systemic hydration
• Patient compliance
• Method of humidification in use
• if any of the above list remain a
problem the current method of
humidification may be
inadequate

63. Additional devices for high flow
• T-PIECE ADOPTOR
Used on end of ET tube
Prove when weaning from
ventilator
is accurate FIO2
Provides good humidity

64. Airway adjuncts

65. Airway Adjuncts
• Oropharyngeal Airway (OP)
– Helps prevent tongue from obstructing posterior
pharynx
– Potential use in unconscious patient
– Cannot use in patients with intact gag reflex
– SIZING: measure from corner of mouth to angle of
jaw
– PLACEMENT: direct method vs rotation method.

66. Airway Adjuncts
• Nasopharyngeal Airway (NP)
– Unconscious or depressed mental status
– SIZING: Measure from the tip of the nares to the
tragus of ear
– CONTRAINDICATIONS: basilar skull fracture,
midface fractures, bleeding disorders
– Relative contraindication: children < 1 year old

67. OXYGENATION AND VENTILATION
Bag-Valve-Mask
With oxygen reservoir

69. Bag-Mask Ventilation
• Key—ventilation volume: “enough to produce
obvious chest rise”
1-Person:
difficult, less effective
2-Person:
easier, more effective
OXYGENATION AND VENTILATION

70. Successful bag-mask ventilation
depends on three things:
• Patent airway :Airway patency can be
established using basic airway maneuvers
• Adequate mask seal :In order to secure a
good seal, the mask must be placed and held
correctly
• Proper ventilation (ie, proper volume, rate )

71. LMA
• Dr. Archie Brain developed LMA in 1982 as a
modification of Goldman dental mask.
• Standard of airway management , filling the
niche between facemask and tracheal tubes.
• They sit outside the trachea and provide a
handsfree means of gas tight airway.
• The first Supraglottic airway device was LMA-
Classic(1989)

72. Indications Contraindications
Alternative Airway during GA Risk of aspiration
Essential part of difficult airway trolley Local pathology in pharynx , larynx or
upper airway.
Cardiopulmonary resuscitaion :
to secure airway
Trismus, facial or upper airway trauma
Relative indication in professional singers:
To avoid trauma to vocal cords
Morbid obese, > 14 week pregnant,
prior opiods medication, delayed gastric
empting
Reduced lung compliance/increase work
of breathing

73. LMA Classic

74. ENDOTRACHEAL TUBE
(ET Tube)

75. • Endotracheal tubes are curved tubes used for
intubation
• Tubes were previously made up of latex (indian
rubber) and those still available , currently plastic
tubes (PVC) are preferred because of following
advantages :
 Disposable (less chances of infection)
 Hypoallergenic ( since latex allergy is fairly
common)
 Transparent (easy visualization of blockage ETT
due to blood , pus , secretions

76. • THE ET TUBE HAS THE FOLLOWING
COMPONENTS :
 PROXIMAL END – 15mm adapter (connector)
which fits to ventilator or AMBU bag
 CENTRAL PORTION –
1. A vocal cord guide (black line ) which should be
placed at the level of the opening of the vocal
cords so that the tip of the ET tube is
positioned above the bifurcation if the trachea.
2. A radio-opaque marker which is essential for
accurate visualization of the position of the ET
tube within the trachea by means of an X-ray

77. 3. The distance indicator (marked in
centimeters) which facilitates placement of
ET tube.
4. A cuff- incase of cuff ET tube
 DISTAL END – has Murphy’s eye (opening in
the lateral wall ) which prevents complete
blockage of ET tube incase the distal end is
impacted with secretion , blood , etc.

78. TYPES
• ET tubes can be :
- cuffed
- uncuffed
• Cuffed ET tubes are used in children > 8 years
• The cuff when inflated maintains the ET tube in proper
position and prevents aspiration of contents from GI
tract into respiratory tract
• In children < 8 uncuffed ET tubes are used because the
narrow subglottic area performs the function of a cuff
and prevents the ET tube from slipping.

79. ENDOTRACHEAL TUBE / ETT

80. High volume
Low pressure cuff
Low volume
High pressure cuff

83. USES
 For Mechanical Ventilation
 For Intermittent Positive Pressure Ventilation
(IPPV)
 During resuscitation
 Direct suctioning of trachea in meconium
aspiration
 In Epiglottits & life threatening croup
 In tetanus (however for long term bases,
tracheostomy is preferable)
 In angioneurotic edema

84. COMPLICATIONS
 Mechanical trauma to tongue, teeth , palate ,
pharynx & larynx during intubation procedure
 Stimulation of posterior of posterior pharyngeal
wall leading to coughing , vomiting or vasovagal
episode with resultant hypoxia , bradycardia.
 Prolonged intubation may cause pressure
necrosis of laryngeal structures leading to
persistant hoarseness ( hence tracheostomy) is
indicated in patients requiring long-term
mechanical ventilation)
 Pneumothorax,Pneumonia

85.  Oxygen tent
 Hood
 Incubator
ENCLOSURES

86. OXYGEN TENT
Consists of a canopy placed
over the head and shoulders
or over the entire body of
a patient
 FiO2 – 40-50% @12-15L/minO2
 Variable performance device
 Provides concurrent aerosol
therapy
 Disadvantage
 Expensive
 Cumbersome
 Difficult to clean
 Constant leakage
 Limits patient mobility

87. OXYGEN HOOD
• An oxygen hood covers only the
head of the infant
• O2 is delivered to hood through
either a heated entrainment
nebulizer or a blending system
• Fixed performance device
• Fio2 – 21-100%
• Minimum Flow > 7/min to
prevent CO2 accumulation

88. INCUBATOR
• Incubators are polymethyl
methacrylate enclosures that
combine servo-controlled
convection heating with
supplemental O2
• Provides temperature control
• FiO2 – 40-50% @ flow of 8-15
L/min
• Variable performance device

89. Evaluation:
Breathing pattern - regular and at normal rate.
 Color - nail beds, lips, conjunctiva of eyes -
pink
 No confusion, disorientation, difficulty with
cognition.
Arterial oxygen concentration or hemoglobin
within normal
 Oxygen saturation within normal limits.

90. Will be explained in other class
ECMO (Extracorporeal
Membrane Oxygenation )

91. HYPERBARIC O2 THERAPY (HBOT)

92. DEFINITION
• A mode of medical treatment wherein
the patient breathes 100% oxygen at a
pressure greater than one Atmosphere
Absolute (1 ATA)
• 1 ATA is equal to 760 mm Hg at sea level

93. Physiological effects of HBO
• Bubble reduction ( boyle’s law)
• Hyperoxia of blood
• Enhanced host immune function
• Neovascularization
• Vasoconstriction

94. INDICATIONS OF HBOT
ACUTE CONDITIONS CHRONIC CONDITIONS
 Decompression sickness
 Air embolism
 Carbon monoxide poisoning
 Severe crush injuries
 Thermal burns
 Acute arterial insufficiency
 Clostridial gangrene
 Necrotizing soft-tissue
infection
 Ischemic skin graft or flap
• Radiation necrosis
• Diabetic wounds of lower
limbs
• Refratory osteomyelitis
• Actinomycosis (chronic
systemic abscesses)

95. Contraindications to Hyperbaric Oxygen
Condition Rationale
Claustrophobia Anxiety
Pneumothorax Gas emboli, pneumomediastinum
Pneumoperitoneum
Tension (pneumothorax)
Subcutaneous emphysema
History of spontaneous
pneumothorax
Increased lung bleb incidence (pneumothorax)
Chronic obstructive
pulmonary disease
Increased oxygen intolerance
Increased risk of seizures
Pneumocystic carinii pneumonia Questionable fetal teratogen
Seizure disorders Barotrauma to sinus/ear/lung
Pregnancy Decreased threshold for oxygen-induced seizures
Upper respiratory infection Increased hemolysis
Hyperthermia
Hereditary spherocytosis
Optic neuritis Questionable - Increased optic nerve pathology
Malignant tumors Questionable - Increased vascularity for tumors
Acidosis Decreased threshold for oxygen seizures

96. METHODS OF ADMINISTRATION of
HBOT

97. Problems with HBOT
• Barotrauma
– Ear/ sinus trauma
– Tympanic membrane rupture
– Pneumothorax
• Oxygen toxicity
• Fire hazards
• Clautrophobia
• Sudden decompression

98. Long Term Oxygen Therapy
• To provide prolong and improve quality of
life in hypoxic pt with COPD
• Indicated For
–Pt with PaO2< 55mmHg or less
–Pt with PaO2< 59mmHg or less plus
peripheral edema, hematocrit of >55% or
P-pulmonale on ECG
Should be reassessed at one
month

99. Complications of Oxygen therapy
1. Oxygen toxicity
2. Depression of ventilation
3. Retinopathy of Prematurity
4. Absorption atelectasis
5. Fire hazard

100. 1. O2 Toxicity
• Primarily affects lung and CNS.
• 2 factors: PaO2 & exposure time
• CNS O2 toxicity (Paul Bert effect)
– occurs on breathing O2 at pressure > 1 atm
– tremors, twitching, convulsions

101. Pulmonary Oxygen toxicity
C/F
 acute tracheobronchitis
• Cough and substernal pain
• ARDS like state

102. Pulmonary O2 Toxicity (Lorrain-Smith
effect)
Mechanism: High pO2 for a prolonged period of time
↓
intracellular generation of free radicals e.g.:
superoxide,H2O2 , singlet oxygen
↓
react with cellular DNA, sulphydryl proteins &lipids
↓
cytotoxicity
↓
damages capillary endothelium,
↓

103. Interstitial edema
Thickened alveolar capillary membrane.
↓
Pulmonary fibrosis and hypertension

104. A Vicious Cycle

105. 2. Depression of Ventilation
• Seen in COPD patients with chronic hypercapnia
• Mechanism
↑PaO2
suppresses peripheral V/Q mismatch
chemoreceptors
depresses ventilatory drive ↑ dead space/tidal volume ratio
↑PaCO2

106. 3. Retinopathy of prematurity (ROP)
• Premature or low-birth-weight infants who receive
supplemental O2
• Mechanism
↑PaO2
↓
retinal vasoconstriction
↓
necrosis of blood vessels
↓
new vessels formation
↓
Hemorrhage → retinal detachment and blindness
To minimize the risk of ROP - PaO2 below 80 mmHg

107. 4. Absorption atelectasis
100% O2
oxygen
nitrogen
PO2 =673
PCO2 = 40
PH2O = 47
A B
A – UNDERVENTILATED
B – NORMAL VENTILATED

108. Denitrogenation Absorption
atelectasis
The “denitrogenation” absorption atelectasis is
because of collapse of underventilated alveoli
(which depends on nitrogen volume to remain
above critical volume )
↓
Increased physiological shunt

114. Take home message!!
• Oxygen is a drug, prescribe it as other drugs, i.e,
amount, device and time should be specified.
• If patient’s SpO2 is not good with nasal cannula,
consider changing the device instead of
increasing flow rate.
• Over jealous use of oxygen is often without
justification & consideration of toxic effects of
oxygen therapy. So think before such
unaccounted for use of oxygen.

115. THANK YOU