2. mechanical ventilator
• A mechanical ventilator is a positive- or
negative-pressure breathing device that can
maintain ventilation and oxygen delivery for a
prolonged period
3. Mechanical ventilation
• Mechanical ventilation The use of a ventilator
to move room air or oxygen-enriched air into
and out of the lungs mechanically to maintain
proper levels of oxygen and carbon dioxide in
the blood.
• Types of ventilators include negative-pressure
and positive-pressure ventilators. Various
ventilator modes are adjusted to the client’s
individual needs.
4. PURPOSE
• To maintain adequate ventilation
• To maintain desired fio2
• To maintain desired tidal volume
• To maintain a pattern airway
• To support the lung
• To Decrease work of breathing
• To Increase alveolar ventilation
• To Maintain ABG values within normal range
• To Improve distribution of inspired gases
5. Indications of mechanical ventilation
• Acute respiratory failure
• Apnoea or impending inability to breathe
• Airway Compromise – airway patency is in doubt
or patient may be at risk of losing patency
• Severe hypoxia
• Respiratory muscle fatigue
• Cardiac Insufficiency
• Neurological problems
• Therapeutic and prophylatic
• Acute lung injury
6. Clinical parameters
• Respiratory Rate ˃ 35/min
• Tidal volume <5ml/kg
• Vital capacity <(15ml/kg body wt)
• PaO2 ˃50mm of Hg with FiO2 ˃ 0.60
• PaCO2 ˃ 55mm of Hg with pH ˃7.25
7. Types
1. Pressure-cycled ventilator: The ventilator
pushes air into the lungs until a specific airway
pressure is reached; it is used for short periods,
as in the postanesthesia care unit.
2. Time-cycled ventilator: The ventilator pushes
air into the lungs until a preset time has elapsed;
it is used for the pediatric or neonatal client.
8. 3. Volume-cycled ventilator
a. The ventilator pushes air into the lungs until a
pre-set volume is delivered.
b. A constant tidal volume is delivered regardless
of the changing compliance of the lungs and
chest wall or the airway resistance in the client
or ventilator.
9. 4. Microprocessor ventilator
a. A computer or microprocessor is built into the
ventilator to allow continuous monitoring of
ventilatory functions, alarms, and client
parameters.
b. This type of ventilator is more responsive to
clients who have severe lung disease or require
prolonged weaning
10. Modes of ventilation
1. Controlled
a. The client receives a set tidal volume at a set rate.
b. Used for clients who cannot initiate respiratory
effort.
c. Least used mode; if the client attempts to initiate
a breath, the ventilator blocks the effort.
2. Assist-control
a. Most commonly used mode
b. Tidal volume and ventilatory rate are preset
on the ventilator
11. 3. Synchronized intermittent mandatory ventilation
(SIMV)
a. Similar to assist-control ventilation in that the
tidal volume and ventilatory rate are preset on the
ventilator.
b. Allows the client to breath spontaneously at her
or his own rate and tidal volume between the
ventilator breaths
c. Can be used as a primary ventilatory mode or as a
weaning mode.
d. When SIMV is used as a weaning mode, the
number of SIMV breaths is decreased gradually, and
the client gradually resumes spontaneous breathing
13. Controls and Settings
Tidal volume
• The volume of air that the client receives with
each breath.
Rate
• The number of ventilator breaths delivered per
minute.
Sighs
• The volumes of air that are 1.5 to 2 times the set
tidal volume, delivered 6 to 10 times per hour;
may be used to prevent atelectasis.
14. Fraction of inspired oxygen (FIO2)
• The oxygen concentration delivered to the
client; determined by the client’s condition and
ABG levels.
Peak airway inspiratory pressure
• The pressure needed by the ventilator to
deliver a set tidal volume at a given
compliance.
• Monitoring peak airway inspiratory pressure
reflects changes in compliance of the lungs
and resistance in the ventilator or client.
15. Continuous positive airway pressure
• The application of positive airway pressure
throughout the entire respiratory cycle for
spontaneously breathing clients.
• Keeps the alveoli open during inspiration and
prevents alveolar collapse; used primarily as a
weaning modality.
• No ventilator breaths are delivered, but the
ventilator delivers oxygen and provides
monitoring and an alarm system; the respiratory
pattern is determined by the client’s efforts.
16. Positive end-expiratory pressure (PEEP)
• Positive pressure is exerted during the
expiratory phase of ventilation, which
improves oxygenation by enhancing gas
exchange and preventing atelectasis.
• The need for PEEP indicates a severe gas
exchange disturbance.
• Higher amounts of PEEP (more than 15)
increase the chance of complications, such as
barotrauma tension pneumothorax.
17. Pressure support
The application of positive pressure on
inspiration that eases the workload of
breathing.
• May be used in combination with PEEP as a
weaning method.
• As the weaning process continues, the amount
of pressure applied to inspiration is gradually
decreased.
18. Causes of Ventilator Alarms
High-Pressure Alarm
• Increased secretions are in the airway.
• Wheezing or bronchospasm causes decreased airway
size.
• The endotracheal tube is displaced.
• The ventilator tube is obstructed because of water or a
kink in the tubing.
• Client coughs, gags, or bites on the oral endotracheal
tube.
• Client is anxious or fights the ventilator.
Low-Pressure Alarm
• Disconnection or leak in the ventilator or in the client’s
airway cuff occurs.
• The client stops spontaneous breathing.
19. Complications of ventilator
1. Hypotension caused by the application of
positive pressure, which increases intrathoracic
pressure and inhibits blood return to the heart
2. Respiratory complications such as
pneumothorax
or subcutaneous emphysema as a result of
positive pressure
3. Gastrointestinal alterations such as stress
ulcers
20. 4. Malnutrition if nutrition is not maintained
5. Infections
6. Muscular deconditioning
7. Ventilator dependence or inability to wean
8.Ventilator associated pneumonia
9.Baro trauma
21. Weaning:
Process of going from ventilator dependence
to spontaneous breathing
1. SIMV
a. The client breathes between the preset
breaths per minute rate of the ventilator.
b. The SIMV rate is decreased gradually until
the client is breathing on his or her own
without the use of the ventilator.
22. 2. T-piece
a. The client is taken off the ventilator and the
ventilator is replaced with a T-piece or
continuous positive airway pressure, which
delivers humidified oxygen.
b. The client is taken off the ventilator for short
periods initially and allowed to breathe
spontaneously.
c. Weaning progresses as the client is able to
tolerate progressively longer periods off the
ventilator.
23. 3. Pressure support
a. Pressure support is a predetermined pressure
set on the ventilator to assist the client in
respiratory effort.
b. As weaning continues, the amount of pressure
is decreased gradually.
c. With pressure support, pressure may be
maintained while the preset breaths per minute
of the ventilator gradually are decreased.
25. Nursing care
1. Assess vital signs, lung sounds, respiratory status,
and breathing patterns (the client will
never breathe at a rate lower than the rate set
on the ventilator).
2. Monitor skin color, particularly in the lips and
nail beds.
3. Monitor the chest for bilateral expansion.
4. Obtain pulse oximetry readings.
5. Monitor ABG results.
26. 6. Assess the need for suctioning and observe the
type, color, and amount of secretions.
7. Assess ventilator settings.
8. Assess the level of water in the humidifier and
the temperature of the humidification system
because extremes in temperature can damage the
mucosa in the airway.
9. Ensure that the alarms are set.
10. If a cause for an alarm cannot be determined,
ventilate the client manually with a resuscitation
bag until the problem is corrected.
27. 11. Empty the ventilator tubing when moisture
collects.
12. Turn the client at least every 2 hours or get
the client out of bed, as prescribed, to prevent
complications of immobility.
13. Have resuscitation equipment available at the
bedside.
14.Hyperventilate the patient before suctioning
15. Provide call bell to patient .
16.Provide note and pen to the patient to
communicate his needs.
