9. INTRODUCTION
Humidification:
• It is the moistening of the air or gases we breathe.
This; is normally one of the functions of the
upper respiratory tract.
• Device:- Humidifier
10. INDICATION
1. When breathing through endotracheal or tracheostomy tubes
2. When breathing air to which gases have been added (0 2 masks)
3. When secretions are abnormally thick
11. WHEN BREATHING THROUGH
ENDOTRACHEAL OR TRACHEOSTOMY
TUBES
Dry air at lower than body temperature passing over secretions in the bronchial tree
extract the moisture from them causing crusts to be formed.
These crusts may partially block the trachea or main bronchus or occlude one of the
smaller airways.
They are very difficult to remove.
Ciliary action i diminished and eventually destroyed in the absence of adequate
humidification.
Artificial humidification is therefore essential for the; maintenance of adequate
ventilation.
12. WHEN BREATHING AIR TO WHICH
GASES HAVE BEEN ADDED (0 2 MASKS)
• Medical gases are completely dry and will require considerably humidification
• and it may be considered advantageous to the patient! to augment the natural
humidification process.
14. TYPES OF HUMIDIFIERS
Humidifiers
Suppliers
Ambient Temperature vapour supplier
Heated vapour supplier
Ambient Aerosol supplier
Heated aerosol supplier
Conservers of water Heat and Moisture exchanger or
condenser humidifier
15. AMBIENT TEMPERATURE VAPOUR SUPPLIER
• Gas is bubbled through room temperature water;
• if passed through a very fine sieve so that the
bubbles are very tiny then some useful
humidification can perhaps be obtained
16. HEATED VAPOUR SUPPLIER
• Gas is blown over a reservoir of heated sterile
water and absorbs water vapour which is then
inhaled by the patient.
• If the delivery tube is cold there is a temperature
drop as the gas passes along the tube and
condensation occurs.
• The humidifier should be positioned below the
level of the patient's airway to avoid flooding of
the airway by condensed water.
17. • Sealed (to prevent contamination) water traps should be included in the circuit to
allow regular emptying without interrupting ventilation.
• A heated delivery tube eliminates the problem of condensation and allows the gas
to be delivered at a desired temperature of 32-36° with a water content of 33-43
g/m3 (Hinds & Watson 1996).
•
• Humiditiers can be used for the spontaneously breathing patient or can be
incorporated into ventilator circuits including continuous positive] airway pressure
and non-invasive ventilation
18. AMBIENT AEROSOL SUPPLIER
• These produce a mist of liquid either by breaking up water entrained by a high
pressure gas on an anvil or
• generating the mist with a high speed spinning disc or an ultrasonic vibrating
crystal.
• Many of these devices are oxygen driven, and entrain room air (using a venturi) in
varying amounts according to the oxygen percentage (0 2%) required.
• The total gas flow varies with the entrainment, and they become rather noisy when
low 0 2 concentrations and hence high rates of air entrainment are used.
• The relative amount of vapour also falls at these high flows.
20. HEATED AEROSOL SUPPLIERS
• The water to be nebulised is heated, and in particular the
Bernouilli-type devices are often made to take a heating
element or ‘hot rod’.
• Thermal safety again is essential.
21. HEAT AND MOISTURE EXCHANGERS
(HMES)
• These heat and moisture exchangers
(HMEs), or condenser humidifiers, trap
expired heat and water in a mesh, and
return it to the fresh inspired gas.
• A heat and moisture exchanger or the
'Swedish nose' are lightweight disposable
devices and may be used in the intubated
patient either mechanically ventilated or
breathing spontaneously
22. • In the spontaneously breathing patient it is important to be aware of the slight
resistance that will increase the work of breathing.
• The humidifier acts in a similar way to the nasopharynx.
• The heat and moisture of the exhaled gas are retained either by condensation or by
absorption, and returned in the inhaled gas as it passes through the device.
• Heat and moisture exchangers are inefficient if there is a large air leak around an
uncuffed tracheostomy tube.
• do not provide adequate humidification for infants.
• If the secretions of a patient using a heat and moisture exchanger become
tenacious, a more effective form of humidification will be required
• The humidifier must be changed at least every 24 hours and immediately if it
becomes soiled with secretions.
23. REFERENCES
1. Cash's Textbook of Chest, Heart and Vascular Disorders for Physiotherapist
2. Physiotherapy for respiratory and cardiac problem by Jennifer A. Pryor.
24. This Photo by Unknown Author is licensed under CC BY