THIS IS VERY IMPORTANT FOR ALL HEALTH CARE PERSONNEL

1. MECHANICAL VENTILATION
Mr. Rahul k. Jaga
Assistant lecture
GCNS, GWALIOR

2. INTRODUCTION
Mechanical ventilation is a life saving
treatment to support patient that are unable to
ventilate and oxygenate on their own, the skill
require by health teams in a ventilation
equipment and proper management of patient
during their course of care.

3. What is Mechanical Ventilation?
• Mechanical ventilation is a form of artificial
respiration that uses a breathing machine
(Mechanical ventilator) to assist patients with
breathing. It is used when the lungs are not
functioning properly.

4. INDICATION
• Acute lungs injury (ARDS, trauma)
• Apnoea with respiratory arrest including cases
from intoxication
• COPD
• Acute respiratory acidosis with partial
pressure of CO2 >50 mmhg and PH <7.35,
which may be due to GBS, myasthenia Gravis,
spinal cord injury, or the effects of anesthesia
and muscles relaxant drugs.

5. Cont…
• Increased work of breathing as evidenced by
significant tachypnoea, retraction and other
physical sign of respiratory distress.
• Hypoxemia with arterial partial pressure of O2
with supplemental function of inspired O2
(FiO2) <55 mmHg.
• Hypotension including sepsis, shock, CHF
• Neurological disease such as muscular
dystrophy , amytrophic lateral sclerosis.

6. CONTRAINDICATION
• Untreated tension pneumothorax
• Medical futility

7. EQUIPMENT
• VENTILATOR MACHINE
• VENTI CIRCUIT
• MASK
• RESERVIOR

8. Indications for mechanical ventilation
• Continuous decrease in oxygenation (PaO2), an
increase in arterial carbon dioxide levels (PaCO2),
and a persistent acidosis (decreased pH),
• Conditions such as thoracic or abdominal surgery,
drug overdose, neuromuscular disorders, inhalation
injury, COPD, multiple traumas, shock, multisystem
failure, and coma all may lead to respiratory failure.

9. Criteria for institution of ventilatory
support:
Parameters Ventilation
indicated
Normal
range
Pulmonary function studies:
· Respiratory rate (breaths/min).
· Tidal volume (ml/kg body wt)
· Vital capacity (ml/kg body wt)
· Maximum Inspiratory Force (cm H2O)
> 35
< 5
< 15
<-20
10-20
5-7
65-75
75-100
Arterial blood Gases
· pH
· PaO2 (mmHg)
· PaCO2 (mmHg)
< 7.25
< 60
> 50
7.35-7.45
75-100
35-45

10. Parts of ventilator

11. Connection to ventilators:
• Face mask: In the resucitation and for minor
procedures under anaesthesia, a face mask is
often sufficient to achive a seal against air
leakge.

12. • Laryngeal mask airway: The laryngeal mask
airway causes less pain and coughing than a
tracheal tube.

13. • Tracheal intubation: A tube is inserted
through nose or mouth and advanced into the
trachea. In most cases tubes with inflatable
cuffs are used for protection against leakage
and aspiration.

14. • Oropharyngeal obturator airway: It is a tube
which is inserted into the oesophagus, past the
epiglottis.

15. • Cricothyrotomy: an airway inserted through
a surgical opening in the cricothyroid
membrane.

16. • Tracheostomy: A tracheostomy is a surgically
created passage into the trachea.

17. • Mouthpiece: less common interface, does not
provide protection against aspiration.

18. Classification of ventilators

19. Classification of ventilators
1. Negative-pressure Ventilator
2. Positive-pressure ventilators.

20. • Negative-Pressure Ventilators
Negative-pressure ventilators exert a negative
pressure on the external chest. Decreasing the
intrathoracic pressure during inspiration allows
air to flow into the lung, filling its volume.
Negative-pressure ventilators are simple to use
and do not require intubation. There are
several types of negative-pressure ventilators:
iron lung, body wrap, and chest cuirass.

22. • Positive-Pressure Ventilators
Positive-pressure ventilators inflate the lungs by
exerting positive pressure on the airway, similar to a
bellows mechanism, forcing the alveoli to expand
during inspiration. Expiration occurs passively.
Endotracheal intubation or tracheostomy is necessary
in most cases.
There are three types:
- Volume - cycled
- Pressure - cycled
- High frequency / special ventilation

23. A. Modes of volume ventilation:
1. Controlled Mechanical Ventilation (CMV)
2. Assist Control (AC)
3. Synchronized Intermittent Mandatory Ventilation
(SIMV)

24. 1. Controlled Mechanical Ventilation (CMV)
The ventilator provides a mechanical breath on a
preset timing. Patients respiratory efforts are
ignored.
Usually only used in an unconscious patient and
anesthetized patient.
The patients performs no WOB and cannot
adjust respirations to meet changing demands.

25. 2. Assist Control (AC)
In this mode the ventilator delivers a pre set tidal
volume at the pre set frequency, and then the patient
initiates a spontaneous breath.
The ventilator senses decrease in intrathoracic pressure
and delivers the preset tidal volume. Patient can
breath faster than preset rate but not slower.
Indications: Neuromuscular disorders, pulmonary
edema, acute respiratory failure.
Patient has potential for hypoventilation or
hyperventilation.

26. 3. Synchronized Intermittent Mandatory Ventilation
(SIMV)
The ventilator provides a preset mechanical breath per every
specified number of seconds (determined by dividing the
respiratory rate into 60 seconds- thus a respiratory rate of 12
results in a 5 second cycle time).
Within that cycle time the ventilator waits for the patient to
initiate breath using either pressure or flow sensor. When
the ventilator senses the first patients breathing attempt
within the cycle, it delivers the preset ventilator breath. If
the patient fails to initiates the breath, the ventilator delivers
the mechanical breath at the end of the breath cycle.
SIMV is frequently employed as a method of decreasing
ventilator support (weaning) by turning down the rate.

27. B. Mode of pressure ventilation:
1- Pressure-controlled ventilation (PCV)
2- Pressure-support ventilation (PSV)
3- Continuous positive airway pressure (CPAP)
4- Positive end expiratory pressure (PEEP)
5- Noninvasive bi-level positive airway pressure
ventilation (BiPAP)

28. 1- Pressure-controlled ventilation (PCV)
Ventilation is completely provided by the mechanical
ventilator with a preset tidal volume, respiratory rate
and oxygen concentration.
Ventilator totally controls the patient’s ventilation i.e.
the ventilator initiates and controls both the volume
delivered and the frequency of breath.
Client does not breathe spontaneously.
Client can not initiate breathe

29. 2- Pressure-support ventilation (PSV)
The patient breathes spontaneously while the ventilator
applies a pre-determined amount of positive pressure
to the airways upon inspiration.
Pressure support ventilation augments patient’s
spontaneous breaths with positive pressure boost
during inspiration i.e. assisting each spontaneous
inspiration.
Helps to overcome airway resistance and reducing the
work of breathing.

30. 3- Continuous positive airway pressure
(CPAP)
Constant positive airway pressure during spontaneous
breathing.
CPAP can be used for intubated and non intubated
patients.
It may be used as a weaning mode and for nocturnal
ventilation (nasal or mask CPAP)

31. 4- Positive end expiratory pressure (PEEP)
Positive pressure applied at the end of expiration during
mandatory ventilator breath
Positive end-expiratory pressure with positive-pressure
(machine) breaths.

32. 5-Noninvasive bi-level positive airway
pressure ventilation (BiPAP)
BiPAP is a noninvasive form of mechanical ventilation
provided by means of a nasal mask or nasal prongs, or a
full-face mask.
It allows to select two levels of positive-pressure support:
An inspiratory pressure support level (referred to as IPAP)
An expiratory pressure called EPAP (PEEP/CPAP level).

33. C. Special modes:
1. High frequency ventilation (HFV)
2. Non-invasive positive pressure ventilation (NIPPV)
3. Partial liquid ventilation (PLV)
4. Nitric oxide
5. Prone position
6. Extracorporeal membrane oxygenation

34. 1. High frequency ventilation (HFV)
The ventilation that occurs at rates significantly above
natural breathing (as high as 240-900 “breaths” per
minute).
Three principal types:
1. High frequency jet ventilation (HFJV)
2. High-frequency flow interruption (HFFI)
3. High-frequency oscillatory ventilation (HFOV)

35. 2. Non-invasive positive pressure ventilation
(NIPPV)
Non-invasive ventilation refers only to the patient
interface and not the mode of ventilation used; modes
may include spontaneous or control modes and may
be either pressure or volume modes.

36. 3. Partial liquid ventilation (PLV)
Currently, clinical trials are investigating the use of
Perflubron (liquid vent) in partial liquid ventilation
(PLV) for the patient with ARDS.
Perflubron is an inert biocompatible, clear odorless
liquid derived from organic compounds that has an
affinity for both oxygen and carbon dioxide and
surfactant like quality.

37. 4. Nitric oxide
A gaseous molecule synthesized intravascularly and participate
in regulation of pulmonary vascular tone. Inhibition of nitric
oxide production results in pulmonary constriction and
administration of continuous inhaled NO results in
pulmonary vasodilation.
5. Prone position
Repositioning of a patient from supine to lateral and to prone
position. In this position heart rests on sternum, away from
the lungs, contribution to an overall uniformity of pleural
pressure.
6. Extracorporeal membrane oxygenation
Extracorporeal membrane oxygenation is alternative form of
pulmonary support for the patient with severe respiratory
failure.

38. Adjustment on the ventilator
• The ventilator is adjusted so that the patient is
comfortable and “in sync” with machine.
• Minimal alteration of the normal
cardiovascular and pulmonary dynamics is
desired.
• If the volume of ventilator is adjusted
appropriately the patient arterial blood level
will be satisfactory and there will be no or
little cardiovascular compromise.

39. The following guidelines are
recommended
• Set the machine to deliver required tidal
volume (6-8 ml/kg)
• Adjust the machine to deliver lowest
concentration of the O2 to maintain normal
PaO2 (80-100 mmHg), the setting may be set
high and gradually reduced based on ABGs
result.
• Record peak inspiratory pressure

40. Cont.…
• Set mode (assist/control or SIMV) and rate
acc. To physician order.
• If patient is on assist / control mode, adjust
sensitivity so that the patient can trigger the
ventilator with the minimum effort (usually
2mmHg negative inspiratory force)
• Record minute volume and measure PaCO2,
PH after 20 minute for MV.

41. Cont..
• Adjust FiO2 and rate according to result of ABG to
provide normal value or those set by the physician.
• In case of sudden onset of confusion, agitation or
unexplained “bucking the ventilator” the pt. should be
assessed for hypoxemia and manually ventilated on
100% O2 with resuscication bag value mask.
• Pt. who are on controlled ventilation and have
spontaneous respiration may “fight or buck” the
ventilator, because they cannot synchronized their own
respiration with the machine cycle.

42. complications
handouts
Decrease cardiac out put
Barotrauma
Nosocomial pneumonia
Decreased renal perfusion
Increased intracranial pressure
Hepatic congestion worsening of intracardiac
shunts.

43. Other common potential problems
• Pamplets

44. Nursing management
• pamplets

45. ANY QUESTIONS???????