This document discusses oxygen therapy, including definitions, types of devices, and complications. It begins with an overview of oxygen therapy and physical properties of oxygen. Various oxygen delivery devices are described, such as nasal cannula, masks, and venturi masks. Indications, advantages, and disadvantages are provided for each device. Complications of oxygen therapy include pulmonary issues like hypercapnea, absorption atelectasis, and drying of secretions. Manual resuscitators are also briefly covered.

1. OXYGEN THERAPY

2. OVERVIEW
Definition
Hypoxia vs Hypoxemia
Recommendations for O2 Therapy
Classification of O2 Therapy
Types of O2 Therapy Devices
Various O2 Therapy Devices
Manual Resuscitator
Complications of O2 Therapy

3. INTRODUCTION
Oxygen therapy refers to administration of Oxygen for
Therapeutic Modality at concentrations of pressure at or
greater than that found in environmental atmosphere.
Oxygen therapy intents on Prevention and treatment of
Hypoxia.

4. Physical properties
Colorless, odorless, tasteless
MW- 32
SG- 1.105
BP @ 760mmHg - -183deg C
Melting point - -218dec C
Plasma solubility @ 37deg C – 0.003ml/100ml blod/mmHg PaO2
Solubility in H2O @ 37deg C – 2.4ml/100ml water
Supports combustion
Below -183 deg C it is transparent blue liquid and slightly heavier than
water
Critical temp - -118deg C

5. Fio2 – fraction of inspired o2 – 0.21/21%
Pao2- partial pressure of o2 in arterial blood
-98-100mmHg(5-6 times the Fio2)
SaO2 – saturation of Hb in arterial blood-100%
Pvo2-partial pressure of o2 in venous blood-40mmhg
Svo2-saturation of Hb in venous blood-75%

10. Preparation and storage of oxygen
Fractional distillation of liquid air
CO2 removed air is used
O2 and N2 are separated using their boiling points
Stored in liquid form in 1500kg capacity tanks
Tanks insulated by vaccum shell
Temp maintained b/w -175 and 150deg C
CYLINDERS
Black with white shoulders in india
Green in USA
Pin index = 2,5
CAPACITY
E cylinder = 660L/1900 psi
M cylinder = 3450L/2200psi
H cylinder = 6900L/2200psi
Pressure at pipeline/ circuit – 4bar/60psi
Prssure @ pressure regulator – 400Kpa/60psi

11. HYPOXIA VS HYPOXEMIAHYPOXIA- Lack of Oxygen at Tissue Level.
HYPOXEMIA-Low O2 Tension {<60mmhg}
in Arterial Blood.

14. CAUSES OF HYPOXIA
ARTERIAL HYPOXEMIA
1. Low Inspired Oxygen
Partial Pressure (High
Altitude).
2. Alveolar
Hypoventilation(Sleep
Apnoea, Narcotic overdose).
3. VQ Mismatch(Atelectasis,
Pneumonia)
4. R-L Shunts
FAILURE OF O2-Hb
TRANSPORT SYSTEM
1. Inadequate Tissue Perfusion
(MI,Shock)
2. Low Hb
Concentarion(Anemia)
3. Increased O2 Requirement
in Hypermetabolic States
4. Abnormal O2 Dissosiation
Curve(Hemoglobinopathies)
5. Histotoxic Poisoning Of
Intracellular
enzymes.(Cyanide
Poisoning)

15. INDICATIONS
HYPOVENTILATION
CENTRAL DRIVE DEC
Overdose drugs
Inadequate reversal
Chest injuries
Cerebral injury
PERIPHERAL CAUSES
Dec diaph movt
Postop pain
Pulm embolism
Upper airway obstruction
DIFFUSION DEFECTS
Pulm oedema
Retained secretions
INCREASED DEMAND
Convulsions
Postop shivering
hyperthermia
SHUNTS
Pulm AV malformtn
Cong HD
Endobronchial intubation
COPD
Atelectasis
Airway obst
Pneumo/hemothx
Secretions
DEAD SPACE
PE
Pulm obst
PAH
cardiac failure
shock

16. GOALS OF OXYGEN THERAPY
Inc o2 content of blood
Inc oxygen delivery to tissues
Achieve Pa02 >60mmHg with FiO2 <0.5
Achieve Spo2 >90% with Fio2 <0.5
Decrease myocardial and respiratory workload

17. RECOMMENDATIONS OF
OXYGEN THERAPY
{Given by American College of Chest Physician& National
Heart Lung&Blood Institue}
1. Cardiac and respiratory arrest
2. Hypoxemia (PaO2<60mmhg,Sao2<90%)
3. Hypotension (Systolic BP<100mmhg)
4. Low Cardiac Output & Metabollic Acidosis
5. Respiratory distress (RR > 24/min)

18. CLASSIFICATION OF O2
THERAPY
NORMOBARIC O2
THERAPY
Devices that deliver
Oxygen at or just above
atmospheric pressure.
HYPERBARIC O2
THERAPY
Supplemental Oxygen
delivered by dissolving it
under pressure in plasma
It is required when Oxygen
carrying capacity of Hb is
compromised or when
Extra Tissue oxygen is
required.

19. TYPES OF O2 THERAPY
DEVICES
CRITERIAS-
1. Flow- High Flow Vs Low Flow
2. Performance- Fixed Vs Variable Performance
3. Patients Indepedent vs Patient Dependant
4. Degree of capacity-no/Low/Medium/High.

20. TYPES OF O2 THERAPY DEVICES
Low Flow/Variable
Performance/Patient
Dependant
1.No Capacity Systems
Nasal Cannula,Nasal Catheters
2.Low Capacity(<100ml)
Simple&Nebuliser Face mask for
children
3.Medium Capacity(100-250ml)-
Simple&Nebuliser Face mask for
Adults.
4.High Capacity(250-1500ml)
Face Mask with reservoir bag.
5.Very High Capacity(>1500ml)
Incubators,Oxygen Hoods&Tents)
High Flow/Fixed
Performance/Patient
Independant
1. Venturi Mask
2. Nebuliser
3. Oxygen hood
4. Hyperbaric Oxygen
INTRAVENOUS OXYGEN
THERAPY
ECMO

21. Low Flow/Variable
Performance/Patient
Dependant
1. Fresh Gas Flow is inadequate
to meet Total Inspiratory
Flow of the
patient.(Entrainment of Room
Air can occur).
2. FiO2 varies with RR & Tidal
Volume.
3. (Unpredictable FiO2).
4. Fio2 depends on capacity of
anatomical reservoir
5. Rebreathing occurs
6. Used in Patients with Stable
Breathing Pattern
7. Humidity and temperature of
gas not controlled
High Flow/Fixed
Performance/Patient
Independant
1. Fresh gas flow is adequate
enough to meet the
Inspiratory Flow of Patient.
(No Entrainment of air)
2. FiO2 not influenced by
RR/Tidal volume.
3. (Fixed and Accurate FiO2).
4. Fio2 doesn’t depend on
capacity of anatomical
reservoir
5. No rebreathing
6. Used in Dyspniec patients.
7. Humidity and temperature of
gas can be controlled
V
s

22. O2 THERAPY DEVICES
Name
Description
Type
Flow Rate
FiO2
Indications
Advantages
Disadvantages

23. NASAL CANNULA
TYPES:Low flow/Variable/No capacity
2 Soft Prongs arising from O2 Tubing inserted
1cm into anterior nares.
Nasopharynx acts as a Anatomic
reservoir(50ml)
INDICATION-
1.Pt. With low O2 requirement.
2.Stable breathing pattern
3.Home Oxygen Therapy.

25. NASAL CANNULA
Flow Rate- 0.5-5 lit/min
FiO2- Sharpies & harrison formula
Final FiO2=Reservoir O2+Nasal O2+Room Air O2.
Exact Fio2 cant be calculated
FLOW ( lit/min) FiO2 (%)
1 24
2 28
3 32
4 36
5 40

26. NASAL CANNULA
Advantages-
1)Simple & Cheap
2)Comfortable for Patient also for Home O2 Therapy.
3)Can be worn during eating or drinking
Disadvantages-
1)Drying&irritation of nasal cavity.
2)Unpredictable FiO2
3)Max FiO2 achieved is 40%.

27. NASOPHARYNGEAL
CATHETER
TYPE- Low Flow/Variable Performance/Low
Capacity
8-14 Fr,Soft Tube with several distal holes
Inserted upto soft uvula fold and then pulled
back slightly so that tip lies beyond posterior
nares above uvula.
Depth of insertion: Ala nasi to Tragus.
Oropharynx acts as a Anatomical reservoir
Catheter is alternated between nares every 8-
12 hours & Changed daily.

30. NASOPHARYNGEAL
CATHETER
FLOW RATE-
Upto 3 L/min- Conscious Pt.
Upto 6 L/min- Unconscious Pt.
FiO2-Upto 40%
Disavantage-
1.Unpredictable Fio2
2.Skin Irritation
3.Excess Secretions or Mucosal Inflammations
4.Less complaince due to Frequent catheter change

31. SIMPLE OXYGEN MASK
TYPES-Low Flow/Variable Performance
Marcy catteral mask
Small Capacity-For Paeds (10-100mL)
Medium Capacity-For Adults (100-250mL)
Plastic Reservoir fitted over Patients’s Nose&Mouth.
O2 collected in apparatus dead space at the end of
expiration is inahaled at the beginning of next breath.

32. SIMPLE OXYGEN MASK
Exhaled gases are vented out through holes on each side
of the mask which also serves as Room-Air Entrainment
Ports.
FLOW RATE- 5-10L/min
>Min Flow Rate:4L/min(To avoid Rebreathing)
>Max Flow Rate:10L/min(Increasing Flow beyond
10L/min won’t increase FiO2,
The excess gas will be vented out through Side Holes.

36. SIMPLE OXYGEN MASK
Flow rate FiO2
5-6L/min 40%
6-7L/min 50%
7-8L/min 60%
ADVANATGE- Quick and Easy to apply.
Disadvantage-1.Unpredictable FiO2
2.Not more than 50-60% FiO
3.Chances of CO2 ReBreathin

37. AEROSOL NEBULISER FACE
MASK
TYPES-Low flow/Varaible Performance
Mask with Large Side Holes attached by a large bore
tubing to a nebuliser.
Flow Rate- 5-10L/min
FiO2- Max upto 50%.

38. RESERVOIR FACE MASK
TYPE:Low Flow/Variable Performance/High Capacity
Provides Higher FiO2 as Reservoir bag is attached to Face
mask.
ADVANTAGE:
>Fast & Easy Setup
>Higher FiO2.
DISADVANTAGES:
>Not tolerated by Claustrophobic Patients.
>Rebreathing can occur if O2 flow is very low.

40. RESERVOIR FACE MASK
Partial Rebreathing FaceMask
Reservoir receives Fresh
Gas
+Exhaled Gas.
Potentially conserves
oxygen as O2 in exhaled
gas gets combined with
Fresh Gas flow.
Flow rate:6-10L/min
FiO2: 40-70%.
Non Rebreathing Face
Mask(with unidirectional
valve)
Not permit mixing of Fresh gas
with Exhaled gas.
Consists of 2 One Way Valve
>Over Reservoir bag-
Prevents entry of reservoir
gases.
>Over one of the side
ports-
Limits entrainment of
Room Air during Inspiration.
Flow Rate: Min. 10L/min
FiO2: 75-90% at 12-15L/min

43. HIGH FLOW SYSTEMS
TYPES- High Flow Fixed Performance Systems
It delivers O2 at flows that meet/exceeds Patient’s
inspiratory flow.
No Rebreathing
(CO2 gets washed out by Gas Flow which constanly
exceeds patient’s requirement.)
Flow Rate- 10-15L/min.

44. VENTURI MASK
A.k.a. HAFOE (High Airflow with Oxygen
Enrichment)
Venturi Effect is based on Bernoulli Principle
Pressure of Gas/Liquid is inversely proportional
to Velocity of gas/liquid in Laminar Flow.
When a fluid flows through a narrow
constriction,The fluid velocity must increase to
satisfy the equation of Continuity.
Hence,When a stream of Gas is pushed through
Narrow orifice,Pressure on outside of Stream
falls.

47. RI MASK
When oxygen under pressure is forced through a small jet
orifice entering the mask----a negative pressure is created.
This causes Room Air to be entrained into the Venturi Barrel.
FGF gets mixed with Room Air.
Hence this increases the overall FiO2 delivered to the patient.
The amount of room air which can be entrained into the venturi
mask will be decided by the width of entrainment port which is
pre-decided for each type of Venturi mask and they are
segregated by Colour coding system.
Due to High Flow rates,Excess gas flushes out expired CO2
through the holes on side of mask.(So there is no
Rebreathing/No increase in Dead Space).

48. • O2 enters at point A(100%)
• O2 flows to wider point B
through a narrow orifice
• Pressure at narrow point
decreases (venturi effect)
which pulls in room air
through the entrainment
port.
• This dilutes the Fio2 100%
with room air
• Fio2 can be calibrated by
varying aperture controlled
by coloured nozzle

49. VENTURI MASK
Variation in size of Entrainment Ports decides Fio2 &
Variation in Oxygen Flow decides Total Flow delivered.
Entrained Air Flow=
{O2 Flow*(1-FiO2)} / {FiO2-0.2}
Example- If FiO2 is 0.6 , O2 flow 10L/min
Then Entrained Room Air will be 10L/min.
Hence O2 FLOW:Entrained Room Air = 1:1

51. VENTURI MASK
Colour FiO2 O2 Flow Entrained
Air
Total Flow
Blue 0.24 2 51 53
White 0.28 3 41 45
Yellow 0.35 8 37 45
Red 0.40 10 32 42
Green 0.60 15 15 30

52. INDICATIONS
Pulm oedema
Pulm consolidation
ARDS
Inc shunt – COPD asthma
Unstable respiratory pattern
Inadequate ventilator efforts

53. ADVANTAGE
NO NEED FOR Air tight fit
Fio2 can be predicted and
is accurate
Fixed enrichment ratio
independent of Patient’s
venti pattern
No dead space
No rebreathing
Easy to use
DISADVANTAGE
Facial discomfort
Remove while eating
Fio2 may get increased if
enrichment ports are
closed by bedsheet or
sumthn

54. MANUAL RESUSCITATOR
Portable Manual Ventilating Device(AMBU)
INDICTAIONS-
1. Ventilation during Resuscitaion
2. Transport of Patient.
3. Administrating anaesthesia when anaesthesia
machine not available/Not Functioning.
Eg.-MRI,Field Situations

57. MANUAL RESUSCITATOR
TYPES
1. Laerdal Resuscitation Bag
2. AMBU Bag,Denmark.
3. Cardiff Infant Bag
4. Samson Blease Bag
5. Sanjivani Adult Resuscitator
6. The Air Viva Resuscitator

58. Laerdal Resuscitation
Bag
Samson Blease Bag

59. MANUAL RESUSCITATOR
SIZES
TYPE WEIGHT CAPACITY TIDAL
VOLUME
MAX.TV
THAT CAN
BE
DELIVERED.
ADULT >30KG 1600ml 600ML 1000ML
CHILD 7-30KG 500ML 350ML
NEONATE <7KG 20-50ML 205ML

60. AMBU
Artificial Mandatory Breathing Unit/Air Mask Bag Unit.

61. COMPLICATION OF OXYGEN
THERAPYPULMONARY
a. Progressive Hypercapnea
if respiratory drive is dependent on hypoxic stimulus
Higher FiO2 causes Hypoventilation which leads to Hypercarbia
Common in COPD pts – resp center is insensitive to hypercarbic drive
This can be prevented by controlling FiO2 to 24-30% in COPD
b. Absorption Atelectasis
When 100% O2 is given to a patient
O2 displaces N2.
Since O2 is more soluble and gets absorbed
O2 in airway gets absorbed causing alveolar collapse.
Changes are seen within 6mins of 100% Fio2
c. Drying and Crusting of Secretions
d. Nitrogen Narcosis (HBOT)

62. COMPLICATION OF OXYGEN
THERAPYCardiovascular
Cardiovasular Depression
HBOT has cardiac depressant action- mainly in pts with
increased sympathetic activity
Sudden correction of hypoxia- cuts of the symp overactivity-
sudeen drop in bp – circulatory collapse
Others-
a)Fire Hazards
b)Depression of Hematopoeisis
c)Oxygen Toxicity

63. OXYGEN TOXICITY
Introduction-
 Production of free radicals from oxyegn
molecule (eg.Superoxide ions, Hydrogen
Peroxide, Singlet Oxygen)
 Causing damage to Structures like
DNA,Lipids
,-SH Containing Proteins.
Measurement-Unit Pulmonary Toxic Dose
 <1425 UPTD-10% fall in vital capacity.
>2190 UPTD -20% fall in vital capacity.

64. OXYGEN TOXICITY
Pulmonary Toxicity: Lorren Smith Effect
 When O2 is given at pressures between
0.7-3 atm;
After 30 hrs exposure to Pio2 of 100pka
 Patient c/o Substernal Discomfort,Chest
Pain,Cough,Decreased
VC,RR,MV,Compliance,Frank ARDS.

65. CNS TOXICITY: Paul Bert Effect
 Occurs when O2 is given at 2atm pressure
 There is inactivation of –SH containing enzymes
which control GABA levels.
 Patient c/o Twitching of perioccular/perioral
muscles, Pupillary Dilataion,Visual
dazzle,Vertigo,Nausea,Numbness,Seizures.
 Rx: Gradual Withdrawal,Inhalation of room
Air,Anticonvulsant.

66. OXYGEN TOXICITY
Retrolental Fibroplasia.
 Occurs in Premature infants with
<30weeks gestation or <1200 gm
birth weight
 There is O2 induced Retinal
Vasoconstriction.
Retinopathy Of Prematurity