oxygen therapy

1. OXYGEN DELIVERY
SYSTEMS
PRESENTOR – DR. HITHA
MODERATOR – DR. DEEPTHI

2. OVERVIEW
◦ Administration of oxygen to children requires selection of
an oxygen delivery system that suits
-Child’s age
-Size
-Needs, clinical condition
-Therapeutic goals

3. OXYGEN TRANSPORT
◦ Dissolved in plasma (2%) & bound to Hb molecule in RBC
(98%)
◦ PaO2 - measure of dissolved oxygen
◦ Dynamic equilibrium - dissolved & haemoglobin-bound
O2
◦ Haemoglobin–oxygen dissociation curve

4. OXYGEN TRANSPORT (contd.)
◦ Haemoglobin - 4 oxygen molecules
◦ Oxygen content of haemoglobin - oxygen saturation
◦ Ratio between Hb carrying oxygen and total hb
◦ Oxygen saturation measured by ABG  SaO2
◦ Pulse oximetry - SpO2 (haemoglobin oxygen pulsed
saturation)

5. HAEMOGLOBIN–OXYGEN DISSOCIATION
CURVE
◦ Oxygen saturation of Hb (SpO2 or SaO2 ) to the PaO2
◦ At high PaO2 (i.e. in the lungs) oxygen will bind to Hb
◦ In tissues PaO2 decreases  Hb releases oxygen

6. HAEMOGLOBIN–OXYGEN DISSOCIATION
CURVE (contd.)

7. HAEMOGLOBIN–OXYGEN DISSOCIATION
CURVE (contd.)

8. HYPOXIA & HYPOXEMIA
◦ Hypoxaemia - low levels of oxygen in the blood
◦ Hypoxia - inadequate oxygen in tissues for normal cell
and organ function,
◦ Hypoxia results from hypoxaemia
◦ Hypoxaemia - lower respiratory tract, upper airway
obstruction, severe asthma, RDS , severe sepsis, heart
failure

9. GOAL OF OXYGEN THERAPY
- To maintain adequate tissue oxygenation while
minimizing cardiopulmonary work

10. CLINICAL OBJECTIVES
1. Correct documented or suspected hypoxemia
2. Decrease the symptoms associated with chronic
hypoxemia
3. Decrease the workload hypoxemia imposes on the
cardiopulmonary system

11. INDICATIONS
◦ Documented hypoxemia as evidenced by
◦ PaO2 < 60 mmHg or SpO2 < 90% on room air
◦ PaO2 or SpO2 below desirable range for a specific clinical
situation
◦ Acute care situations in which hypoxemia is suspected

12. ASSESSMENT
◦ The need for oxygen therapy should be assessed by
1. monitoring of ABG - PaO2, SpO2
2. clinical assessment findings

13. PaO2 AS AN INDICATOR FOR OXYGEN
THERAPY
◦ PaO2 : 80 – 100 mm Hg : Normal
60 – 80 mm Hg : cold, clammy
extremities
< 60 mm Hg : hypoxemia
< 40 mm Hg : mental deficiency
memory loss
< 30 mm Hg : bradycardia
cardiac arrest
PaO2 < 60 mm Hg is a strong indicator for oxygen therapy

14. SOURCES OF OXYGEN
◦ OXYGEN CYLINDERS
Operate at 1800-2400 psi
Need down regulating valve
Flow meter to manipulate flow rate
Cannot be directly connected

15. SOURCES OF OXYGEN (contd.)
OXYGEN CONCENTRATORS
Concentrators draw in air from the environment
Supply oxygen at a concentration of 90–96%
Safe, less expensive, reliable, cost-efficient source of oxygen
Convenient than oxygen cylinders
Low-resource settings

16. SOURCES OF OXYGEN (contd.)

17. SOURCES OF OXYGEN (contd.)
CENTRAL PIPED OXYGEN
System of copper pipes - a central source - located
outside the building
Liquid oxygen, high-pressure gaseous cylinders or a
large oxygen concentrator or a combination

18. SOURCES OF OXYGEN (contd.)
CENTRAL PIPED OXYGEN(contd.)
Pipeline systems supply oxygen at high pressure to
equipment such as anaesthetic machines and ventilators.
Merits – Reduces fire , handling and transporting heavy
cylinders
Demerit - high cost of installing

19. SOURCES OF OXYGEN (contd.)
CENTRAL PIPED OXYGEN(contd.)

20. METHODS OF
OXYGEN DELIVERY

21. OXYGEN DELIVERY SYSTEM
LOW FLOW
1.Nasal prongs
2. Simple face mask
3. Partial rebreathing
mask
4. Non rebreathing mask
HIGH FLOW
1.Venturi type mask
2. Hood box
3. High flow nasal
cannula
4. Bubble CPAP
5. Bag and mask
6. Tracheostomy

22. LOW FLOW SYSTEMS

23. LOW FLOW NASAL CANNULA

24. LOW FLOW NASAL CANNULA (contd.)
◦ Most common
◦ Lightweight , 2 soft prongs that fit in the nares
◦ Different sizes
◦ Standard flow rates - 0.5–1 L/min for neonates, 1–2 L/min
for infants, 1–4 L/min for older children.

25. LOW FLOW NASAL CANNULA(contd.)
INDICATIONS
Children who need oxygen concentrations 22% to 40%
ADVANTAGES
 Allows child to eat, talk, and cough without interrupting oxygen
delivery
No risk of gastric distension at standard flow rates
Humidification not required with standard oxygen flow

26. LOW FLOW NASAL CANNULA(contd.)
DISADVANTAGES
Slight risk of airway obstruction by mucus especially if a
high flow with no humidification
Nasal bleeding

27. LOW FLOW NASAL CANNULA(contd.)
FiO2
Oxygen flow rate
Relation between prong and nasal diameters
 Patient body weight

28. LOW FLOW NASAL CANNULA(contd.)
PEEP
Distal prong diameter
Oxygen flow
Body weight
1 L/min of O2 PEEP of about 5 cm H2O in premature infants

29. SIMPLE FACE MASK

30. SIMPLE FACE MASK (contd.)
◦ Mask sits on face and over mouth and nose - elastic
strap.
◦ Variety of sizes
◦ Minimum oxygen flow – 6L/minute
◦ FiO2 : 35- 50%

31. SIMPLE FACE MASK (contd.)
INDICATION:
Mild to moderate respiratory distress
Medium flow desired
CONTRAINDICATION :
Poor respiratory effort
Severe hypoxia
Apnoea

32. SIMPLE FACE MASK (contd.)
ADVANTAGE
Less expensive
DISADVANTAGE
Do not deliver high concentration of O2
Interferes with eating and talking

34. PARTIAL REBREATHING MASK

35. PARTIAL REBREATHING MASK (contd.)
◦ Simple face mask + reservoir bag
◦ Oxygen flow : 10-15L
◦ Can give Fio2 ranging 50-60 %
◦ Rebreathing of carbon dioxide is prevented if flow is
maintained at higher than child’s minute ventilation

36. PARTIAL REBREATHING MASK (contd.)
INDICATION
Relatively high oxygen requirement
CONTRAINDICATION
Poor respiratory effort
Severe hypoxia
Apnoea

37. PARTIAL REBREATHING MASK (contd.)
ADVANTAGE
Inspired gas not mixed with room air
DISADVANTAGE
Inconsistent FiO2 delivery
Monitor child for signs of hypercarbia
Interferes with eating and talking

38. NON REBREATHING MASK

39. NON REBREATHING MASK (contd.)
◦ Simple face mask + reservoir bag + one way valve into
exhalation port
◦ Oxygen flow into bag is adjusted to prevent collapse
◦ Flow : 10-15L, FiO2 : 65 – 95%
◦ 100 % Fio2 theoretically ; 80-90 % in practice due to leaks

40. NON REBREATHING MASK (contd.)
INDICATION
High oxygen requirement
CONTRAINDICATION
Poor respiratory effort
Severe hypoxia
Apnoea

41. NON REBREATHING MASK (contd.)
ADVANTAGE
High concentration oxygen delivery without intubation
DISADVANTAGE
Expensive
Non availability
Interferes with eating and talking

42. HIGH FLOW SYSTEMS

43. VENTURI TYPE MASK

44. VENTURI TYPE MASK (contd.)
◦ Reliable
◦ Provide controlled , low to moderate (25-60%)

45. VENTURI TYPE MASK (contd.)
INDICATION
 Desire to deliver exact amount of O2 conc
CONTRAINDICATION
Poor respiratory effort
Severe hypoxia
Apnoea

46. VENTURI TYPE MASK (contd.)
ADVANTAGE
Fine control of FiO2 at constant flow
DISADVANTAGE
Expensive
Cannot deliver high concentrations
Interferes with eating and talking
Humidification can alter oxygen concentration with this device
Inconsistent FIO2 delivery may be noted at higher concentrations

47. OXYGEN HOOD

48. OXYGEN HOOD (contd.)
◦ Clear plastic box covers infant’s head
◦ Well tolerated by infants and neonates
◦ Allows access to chest, trunk and extremities
◦ Flow – 5L-15L
◦ FiO2 : 30-90%

49. OXYGEN HOOD (contd.)
INDICATIONS
Neonates or infants who need oxygen
Provides high concentration of oxygen, FIO2 up to 90%
Minimum : 5 Litre
Flow of oxygen 10-15 L/ minute

50. OXYGEN HOOD (contd.)
ADVANTAGE :
High concentration
DISADVANTAGE :
Hypercarbia
Nasal cannula may be needed
Temperature – monitor
Creates moist environment

51. HIGH FLOW NASAL CANNULA

52. HFNC ( contd.)
◦ Newest technique of O2 delivery
◦ Heated ( to room body temp) and humidified
(supersaturated with water)
◦ Flow rate 1-2 L/kg- wide nasal prongs
◦ Minimal mucosal injury or discomfort

53. HFNC ( contd.)
◦ Provides positive pressure in nasopharynx  PEEP 
prevent collapse of alveoli
◦ Avoid intubation and mechanical ventilation
◦ FiO2 : 21 -100%

54. BUBBLE CPAP

55. BUBBLE CPAP (contd.)
◦ CPAP - delivery of mild air pressure to keep the airways
open
◦ Delivers PEEP with a variable amount of oxygen flow
◦ Spontaneously breathing patient
◦ Maintain lung volume during expiration.
◦ CPAP decreases atelectasis and respiratory fatigue

56. 1.Continuous gas flow into the circuit:
 Gas flow rate required to generate CPAP is usually 5–10
L/min, without additional oxygen (FiO2 = 0.21)
 Many require supplemental oxygen- via oxygen blender
BUBBLE CPAP (contd.)

57. 2. A nasal interface connecting the infant’s airway with
the circuit
Short nasal prongs are generally used to deliver nasal
CPAP
Fitted to minimize leakage of , and to reduce nasal
trauma
BUBBLE CPAP (contd.)

58. 3. An expiratory limb
Distal end submerged in water to generate EEP
The positive pressure is maintained by placing the far
end of the expiratory tubing in water
The pressure is adjusted by altering the depth of the tube
under the surface of the water
BUBBLE CPAP (contd.)

59. INDICATIONS
Infants with severe respiratory distress
 Hypoxaemia
BUBBLE CPAP (contd.)

60. SUMMARY
DEVICE FLOW FIO2
NASAL CANNULA 0.5- 2L 22- 40%
SIMPLE FACE MASK 6L-10L 35-50%
PARTIAL REBREATHING
MASK
10L 50-60%
NRBM 10L-15 L 65- 95%
VENTURI MASK 2L-15L 24-60%
OXYGEN HOOD 5L – 15L 30-90%
HFNC 1-2L /KG 21- 100%
BUBBLE CPAP 5-10L 21-100%

61. REFERENCES
◦ Uptodate
◦ Oxygen therapy for children – WHO update
◦ Kumar RM, Kabra SK, Singh M. Efficacy and acceptability of different modes of oxygen administration in
children: implications for a community hospital. J Trop Pediatr. 1997 Feb;43(1):47-9. doi:
10.1093/tropej/43.1.47. PMID: 9078829.
◦ Morley SL. Non-invasive ventilation in paediatric critical care. Paediatric respiratory reviews. 2016 Sep
1;20:24-31.

62. THANK YOU