|
Mode of O2
delivery |
Maximum flow
rate (litres/min |
FiO2 |
Other notable
features |
|
Nasal cannula
/ prongs |
5 |
·
1 litre/min flow rate-24%, ·
increases by 4% with every litre increase in
flow rate ·
6 litres/min flow rate-44%, |
·
Narrow-bored flexible tubes. ·
One end of the tube is attached to a graduated
oxygen flow meter, the other end is split into two nozzles that loosely fits
into the nostrils. ·
Beyond flow rates of 5 litres/min, the flow
becomes turbulent leading to dissipation of delivered oxygen at the entry
portal. |
|
Face mask
(simple) |
5-10 |
35-55% |
·
It is an expanded semi-rigid hollow enclosure
that fits over the nose and oral orifice. ·
Flow rates less than 5 litres/min are not
recommended because there is rebreathing of trapped expired air |
|
Venturi mask |
(blue-2,
white-4, orange-6, yellow-8, red-10 and green-15) |
24, 28, 31,
35, 40 and 60 % respectively |
·
Oxygen inlet to the face mask is fitted with
oxygen content regulators of varying capacity. ·
The FiO2 can therefore be tightly controlled
as per need of the patient |
|
NRBM |
10-15 |
Up to 100% |
·
The oxygen inlet to the mask is side-fitted
with an inflatable oxygen reservoir bag. ·
During inspiration, oxygen is sourced from the
inflowing oxygen as well as from the reservoir. |
|
(HFNC) |
Maximum rate-
70 litres/min |
Up to 100% |
·
electromechanical device that generates an
admixture of warm humidified air containing oxygen of desired concentration |
