The document describes the components and uses of endotracheal tubes, which are curved plastic or latex tubes used for intubation to provide an airway for mechanical ventilation or respiratory support. It details the parts of the ET tube including the proximal end, central portion with markers, and distal end, as well as types, sizing, complications, and uses. The document also provides information on ambu bags, including their parts and mechanism for providing intermittent positive pressure ventilation.

1. ENDOTRACHEAL TUBE
(ET Tube)

3. • 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
comman)
 Transparent (easy visualization of blockage ETT
due to blood , pus , secretions

4. • 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

5. 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.

7. 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.

8. High volume Low volume
Low pressure cuff High pressure cuff

10. SIZE
• From 2mm to 16 mms (internal diameter )
 The size of the tube can be determined by –
internal diameter of ETT (mm) = age in years +4
4
 Roughly the diameter of the childs little finger is
the same as that required for the ETT
 The following table gives an idea abpout the size
of ETT in different age groups.

11. AGE GROUP SIZE OF ET TUBE
PREMATURE BABIES 2 TO 2.5
FULL TERM BABIES UPTO 2 3 TO 3.5
WEEKS
FROM 2 WEEKS TO 24 WEEKS 4 TO 4.5
FROM 6 MONTHS TO 12 4.5 TO 5
MONTHS
Then increase the size of the ET tube by 0.5
cms for every 6 months rise in age so that at
approximately 6 years of age size of the ET
tube to be used is approximately 8 mms

12. USES
 For Mechanical Ventilation
 For Intermittent Postive 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 diptheria
 In angioneurotic edema

13. 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.

14. AMBU BAG
• PARTS OF THE AMBU BAG
 PATIENT OUTLET (to which mask is attached )
 ONE-WAY VALVE UNIT (just proximal to
patient outlet )
 PRESSURE RELEASE VALVE
 Attachment site for manometer

16.  size : the size of the bag varies depending on
the volume ( ranges from 250 ml to 750 ml for
paediatric use)
 pressure release valves : are usually set to
release at pressure of 30-35cms of water
 at the end there are two inlets
 OXYGEN INLET : This inlet is attached to a
tube carrying oxygen from the source (central
oxygen line or oxygen cylinder )
 AIR INLET : if kept open the concentration of
02 is approx 40% FiO2. for the Fi02 to be near
90-100% , and oxygen reservoir should be
attached.

17. MECHANISM OF VENTILATION
 in the resting stage the ambu bag is filled with air
. On squeezing the bag to initiate ventilation the
one wave valve proximal to the patients outlet
opens resulting in release of air , stored in the
bag to the patient. On releasing the pressure the
bag gets re-inflated with air. The patients exhaled
air cannot re-enter the bag due to one wave
mechanism of the valve at the patient outlet.
USES : for giving intermittent positive pressure
ventilation