Mechanical ventilation involves using a machine to help a person breathe. It can be used to treat conditions that affect breathing. The document discusses mechanical ventilators, how they work, indications for their use, complications, modes of ventilation, and the nurse's role in caring for a patient on a ventilator. It provides details on monitoring the patient, maintaining the ventilator and circuits, positioning, nutrition, and preventing complications.
2. Ventilation
Ventilation: Ventilation or breathing is the process of
moving air into and out of the lungs.
Mechanical ventilation: It is a process of giving
artificial respiration through the device “Mechanical
ventilator”.
3. Mechanical ventilator
It is a device to
inflate the lungs
artificially by
positive pressure.
4. Goals of Mechanical Ventilation
Adjust alveolar ventilation
pH, PaCO2
Improve oxygenation
Assess with pulse oximetry
Decrease work of breathing
5. Indications for mechanical ventilation
Cardiac diseases:-
Cardiogenic shock.
Central Nervous system diseases:-
Cerebral trauma.
Cerebrovascular accident.
Spinal cord injury.
10. Negative-pressure ventilators
Negative pressure applied to
chest wall increases the volume
of the thoracic cage
Mimics spontaneous ventilation
Negative intrathoracic pressure
gradient causes air to enter lungs
No need for artificial airway
Used mainly for chronic care of
patients with neuromuscular
disorders
Examples: iron lung, pulmowrap,
chest cuirass
11. Positive-pressure ventilators
Intrathoracic pressure
remains positive throughout
respiration
Force oxygen into the
patients lungs through an
endotrechial or
tracheostomy tube to
initiate respiration.
Gas is distributed to non-
dependent, less-perfused
lung regions
12. Terms related to mechanical
ventilation
Respiratory rate (f): Number of breaths per minute (10 to 20 bpm).
Tidal volume (VT): Volume of air inhaled /exhaled during each respiratory
cycle ( 7 to 12 ml/kg).
Minute ventilation (VE): Volume of air expired per minute. (VE=VT x f;
6 to 8L/min).
Fraction of inspired oxygen(FIO2) - :amount of oxygen delivered to the
patient. It can range from 21% (room air) to 100%.
13. I:E Ratio - The inspiratory time compared to the
expiratory time; I + E = total cycle time. (1:2 or less).
Maximal Inspiratory pressure (MIP): Maximal
negative pressure generated during inhalation.(15
-20cmH2O)
Flow rate: Flow rate is the speed with which the tidal
volume is delivered. (40 to 100 L/min).
14. Cycling: what cycles, or changes, the ventilator
from one phase of the respiratory cycle to the
other. (volume, time, pressure, flow ).
Positive end expiratory pressure(PEEP): keeps the
air way open at the end of expiration ; 5 to 20 cms
of H2O.
15. Classification of PPV
Pressure cycled ventilators- ventilator pushes air
until a preset pressure is reached. It is used for
short periods such as in the post anesthesia care
unit and for respiratory therapy.
16. Volume- cycled ventilator: ventilators pushes air
into the lungs until preset volume is delivered.
Time-cycled ventilators: ventilators pushes air into
lung until a preset time has elapsed. It is used
primarily in pediatric and neonatal population.
17. Modes of Mechanical ventilation
Mode - how the machine will ventilate the patient
in relation to the patient's own respiratory efforts.
The manner or method of support provided by the
ventilator.
18. ASSIST CONTROL MODE(AC)
• Most commonly
• As a resting mode, in which ventilator takes over
the work of breathing for the client.
• Machine initiated and /patient initiated breaths.
• A preset tidal volume and respiratory rate are
delivered.
19. INTERMITTENT MANDATORY VENTILATION(IMV)
ventilator delivers a preset number of mechanical
breaths.
allows the client to breath spontaneously in
between with no assistance from the ventilator
and at varying tidal volume.
20. SYNCHRONIZED INTERMITTENT MANDATORY VENTILATION
(SIMV)
Delivers preset breaths that are synchronized
with the patient’s spontaneous breaths.
preferred mode of weaning.
21. INVERSE RATIO VENTILATION (IRV)
Normal inspiratory :expiratory ratio is reversed to
2:1 or greater (the maximum is 4:1).
Longer inspiratory time increases the amount of
air in the lungs at the end of expiration
Improves oxygenation by reexpanding collapsed
alveoli.
22. PRESSURE SUPPORT VENTILATION (PSV)
Preset pressure augments the patient's
spontaneous inspiration effort and decreases the
work of breathing
Patient completely controls the respiratory rate
and tidal volume.
23. CONTINUOUS POSITIVE AIRWAY PRESSURE (CPAP)
Keeps the alveoli open during inspiration and prevents
alveolar collapse during expiration.
Used in the spontaneous breathing patient.
Used as a method for weaning patients from
mechanical ventilation.
Improves gas exchange and improves oxygenation.
Normal range for CPAP is 5 to 15 cm of H2O.
25. Low pressure alarm
triggered by air leaks.
Causes
Patient disconnection
Circuit leaks -mainline connections to humidifiers,
filters
Exhaled valve leaks: leaking valves, improperly
connected valves
Airway leaks: inadequate cuff inflation, leak in pilot
balloon, rupture of tube /cuff
26. High airway pressure
Triggered when resistance to ventilation is high
Causes
Ventilator problems:
Inappropriate settings, excessive tidal volume, ventilator malfunction – rare
Circuit problems
Fluid pooling in circuit/ filter,kinking of circuit
Endotracheal tube obstruction
Due to sputum, kinking, biting
Increased airway resistance
Bronchospasm, decreased respiratory system compliance, decreased chest
wall compliance
27. Apnea alarms
Activated when no exhalation is detected for a selected
time period (e.g., 20 seconds)
causes
Patient apnea, disconnection, system leaks,
inadequate machine sensitivity,
Inappropriately set apnea parameters
Can be accompanied by low pressure / low minute
ventilation alarms
28. Complications of positive pressure
ventilation. (PPV)
Pneumothorax:Pleural pressure increases, and collapses
the lung, causing Pneumothorax.
Volu-pressure trauma/Barotrauma: the lung injury that
occurs when large tidal volumes are used to inflate non
compliant lungs (eg.ARDS). This results in alveolar
fracture and movement of proteins and fluid into the
alveolar spaces.
29. Alveolar hypoventilation: caused by inappropriate
ventilator setting, leakage of air from ventilator
tubing or around ET tube and tracheotomy cuff,
lung secretions or obstruction, and low ventilation
perfusion ratio.
30. Alveolar hyperventilation: Respiratory alkalosis
can occur if the respiratory rate and tidal volumes
are set too high.
Ventilator-associated Pneumonia: because ET or
tracheostomy tube bypasses normal upper air way
defenses.
31. Sodium and water imbalance: fluid retention
occurs after 48 to 72 hours of PPV. It is associated
with decreased urinary out put increased sodium
retention. Fluid balance changes is due to the
decreased cardiac output.
32. Neurologic system: Increased intrathoracic pressure
impedes venous drainage from the head. This
increases the cerebral blood volume and causes a
rise in intra cranial pressure.
Gastro intestinal system: the ventilated patient is at
the risk of developing stress ulcers and GI bleeding.
33. ROLE OF NURSE IN
CARE OF MECHANICALLY
VENTILATED PATIENT
34. Hand Hygiene
• Wash hands before Use sterlium or
direct contact. 40% of alcohol based
infections are hand rub in
transmitted by the between
hands of Hospital staff procedure or as
required.
35. Recording of vital signs:
• Record vital signs. {Assess for hypotension, tachycardia,
Tachypnoea }
• Observe respiratory pattern & Auscultate lung sounds.
• Observe for breathing pattern in relation to ventilatory cycle.
• Assess for changes in mental status and LOC.
• Continuous pulse oximetry.
• Observe ABG for abrupt changes or deterioration as required.
36. Endotracheal tube care:
• Introduce an oropharyngeal airway.
• Maintain inflation of the cuff at 15 to 20 mmHg.
• Institute Endotracheal suctioning as appropriate.
• Administer humidified oxygen before suctioning
to loosen secretions.
• Change Endotracheal tapes every 24 hours.
• Inspect the skin and oral mucosa.
38. • Stop feeding during 30 – 60 minutes before
suctioning & chest physiotherapy.
• Observe the type, color & amount of
secretion, notify the changes.
• Avoid drawing of arterial blood sample
immediately after suctioning.
• Watch for side effects: hypoxemia,
bradycardia, hypotension.
39. Oral hygiene:
• Provide careful oral hygiene
• Apply lubricant to lips to prevent drying, cracking
and excoriation.
• Rotate the ET tube from one corner of mouth to the
other side atleast every 24 hours.
40. Arterial Blood Gas analysis:
• ABG reflects oxygenation adequacy of gas
exchange in the lungs & Acid-base status.
• Avoid taking sample immediately after
suctioning, nebulisations and baging.
• While drawing blood prevent entry of air in
syringe.
• Send immediately ABG sample to laboratory..
41. Maintain Nutritional need
Basal energy expenditure calculation
[Harris Benedict equation]
Men : 66.47 + (13.75×W) + (5×H) - (6.76 ×A) Kcal/Day
Fem. : 65.51 + (9.56×W) + (1.58×H) - (4.68 ×A) Kcal/Day
[W=Weight of Pt., H=Height of Pt., A=Age of Pt.]
# High protein, High fat & Low carbohydrates diet can be
beneficial.
# Add mineral supplements to the diet especially magnesium &
phosphorus. These are essential for energy production &
respiratory muscle function.
42. Positioning:
• Turn and reposition the patient every 2nd
hourly.
• Positioning prevents complications such as
pneumonia and atelectasis.
43. Personal hygiene:
• Frequent oral hygiene must be done.
• Eye care to be given every 4th hourly to prevent
corneal ulcers and dryness of conjunctiva.
• Provide skin care.
• Provide catheter care using sterile technique.
44. Allaying anxiety & fear:
• Explain all the procedures to the patient &
relatives to win their confidence.
• Talk and clear the doubts of patient &
attainders. Never ignore there feelings.
• Use therapeutic touch.
• Encourage the family members to visit the
patient as per hospital policy.
45. Care of ventilator circuit:
• Keep the water level in humidifier in normal
limit.
• Humidification during mechanical ventilation
required to prevent hypothermia, inspissations'
of airway secretions, destruction of airway
epithelium & atelectasis.
• A heated humidifier should be set to deliver an
inspired gas temperature of 33 -/+ 2˚C.
• The temperature of inspired gas should not
exceed 37˚C at the airway threshold.
• Sterile water should be used only.
46. • Condensation from the patient circuit should be
considered infectious waste and should never be
drained back in to the humidification reservoir.
• Change the circuit when it is visibly soiled or
mechanically malfunctioning.
• Bacterial filters should not be used for more than 48
hours.
• Use universal precautions when involved in circuit
changes.
47. Care of ventilator alarms:
• Never Shut Alarms Off – Alarm system must be
activated and function at all time. It is acceptable
to silence alarms for a preset delay while
suctioning and during oxygen flush before
suctioning.
• If equipment failure is suspected and unable to
determine the cause of alarm, Manually
ventilate the patient with resuscitation bag until
the problem is corrected.
48. VENTILATOR CARE BUNDLE
Acc to IHI “bundle” is a group of evidence –based
care components for a given disease that ,when
executed together ,may result in better outcomes
than if implemented individually.
49. VENTILATOR CARE BUNDLE
It includes :
DVT prophylaxis(unfractioned heparin,elastic
stockings,pneumatic compression,elevation of
affected extrimity,gentle foot & leg exercise,fluid
administration)
GI prophylaxis(H2 blocker /proton pump inhibitor)
Head of bed elevated to 30-45
The goals of mechanical ventilation include: adjusting alveolar ventilation to bring pH and PaCO 2 within the patient’s normal range, improving oxygenation to acceptable levels given the age of the patient and disease process, and decreasing the work of breathing. Before we move on with our discussion of mechanical ventilation, we should take a look at how spontaneous breathing occurs.
Vital capacity – amount of air displaced by maximal exhalation. Minute ventilation -Volume of air expired per minute
Negative-pressure ventilation mimics spontaneous ventilation. A negative extrathoracic pressure applied to the chest wall increases the volume of the thoracic cage. This results in a negative intrathoracic pressure gradient and causes air to enter the lungs. One advantage of negative-pressure ventilation is that it requires no artificial airway. It is used mainly for chronic care of patients with neuromuscular disorders such as ALS, MS, etc. Some adult polio victims and kyphoscoliosis patients still use the iron lung. Other examples of negative-pressure ventilators are the pulmowrap and chest cuirass. Almost all ventilators currently being used in hospitals today are positive-pressure ventilators.
Combination of machine and spontaneous breath.mandatory breaths delivered when pt effort sensed.pt determine the TV and rate
used in the spontaneous breathing patient who may or may not be intubated. It can be administered also via face mask.
Let’s turn our focus to ventilator alarm management, including high and low airway pressure alarms, rate alarms, and volume alarms. Alarms warn the clinician about technical and patient conditions that can negatively impact the ventilator’s ability to provide support. Alarms can be audible and/or visual, depending on the severity of the alarm condition. Alarms can only provide warning if set appropriately. When a ventilator alarm is activated, the clinician needs to respond, identify the alarm parameter that has been violated, and institute corrective action. Since many different situations can cause an alarm condition, the clinician should employ a systematic approach to troubleshoot the problem. All clinicians need to be familiar with ventilator messages and alarms, and must be able to troubleshoot. If you can not readily identify the problem and the patient is in distress, disconnect the patient from the ventilator and provide manual ventilation.