PresentationPDF Available

What Are the Different Types of Mechanical Ventilation?

Authors:

Abstract

Mechanical ventilation is a treatment to help a person breathe when they find it difficult or are unable to breathe on their own. A mechanical ventilator pushes airflow into the patient's lungs to help them breathe. #DrRohitBhaskar #BhaskarHealth
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
VENTILATOR
MECHANICAL VENTILATION
PRESENTED BY
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
INDICATIONS:
1- Acute respiratory failure due to:
Mechanical failure, includes neuromuscular diseases as Myasthenia
Gravis, Guillain-Barré Syndrome, and Poliomyelitis (failure of the
normal respiratory neuromuscular system)
Musculoskeletal abnormalities, such as chest wall trauma (flail
chest)
Infectious diseases of the lung such as pneumonia, tuberculosis.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
2- Abnormalities of pulmonary gas exchange
as in:
Obstructive lung disease in the form of asthma,
chronic bronchitis or emphysema.
Conditions such as pulmonary edema, atelectasis,
pulmonary fibrosis.
Patients who has received general anesthesia as well
as post cardiac arrest patients often require
ventilatory support until they have recovered from the
effects of the anesthesia or the insult of an arrest.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
CRITERIA FOR INSTITUTION OF VENTILATORY
SUPPORT:
Normal range Ventilation
indicated
Parameters
10-20
5-7
65-75
75-100
> 35
< 5
< 15
<-20
A- Pulmonary function
studies:
Respiratory rate
(breaths/min).
Tidal volume (ml/kg
body wt)
Vital capacity (ml/kg
body wt)
Maximum Inspiratory
Force (cm HO2)
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
CRITERIA FOR INSTITUTION OF
VENTILATORY SUPPORT:
Normal rangeVentilation
indicated
Parameters
7.35-7.45
75-100
35-45
< 7.25
< 60
> 50
B- Arterial blood
Gases
PH
PaO2(mmHg)
PaCO2(mmHg)
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
PHASES OF VENTILATOR
I. Inspiratory Phase.
II. Cycling, or changeover, to expiration.
III. Expiratory Phase.
IV. Cycling to inspiration.
TYPES OF MECHANICAL
VENTILATORS:
Negative-pressure ventilators
Positive-pressure ventilators.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
NEGATIVE-PRESSURE VENTILATORS
Early negative-pressure ventilators were known as iron
lungs.
The patients body was encased in an iron cylinder and
negative pressure was generated .
The iron lung are still occasionally used today.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Intermittent short-term negative-pressure ventilation
is sometimes used in patients with chronic diseases.
The use of negative-pressure ventilators is restricted
in clinical practice, however, because they limit
positioning and movement and they lack adaptability
to large or small body torsos (chests) .
Our focus will be on the positive-pressure ventilators.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
POSITIVE-PRESSURE VENTILATORS
Positive-pressure ventilators deliver gas to the
patient under positive-pressure, during the
inspiratory phase.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
TYPES OF POSITIVE-PRESSURE
VENTILATORS
1- Volume Ventilators.
2- Pressure Ventilators
3- High-Frequency Ventilators
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
1- VOLUME VENTILATORS
The volume ventilator is commonly used in critical
care settings.
The basic principle of this ventilator is that a
designated volume of air is delivered with each
breath.
The amount of pressure required to deliver the set
volume depends on :-
- Patients lung compliance
- Patientventilator resistance factors.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Therefore, peak inspiratory pressure (PIP ) must be
monitored in volume modes because it varies from
breath to breath.
With this mode of ventilation, a respiratory rate,
inspiratory time, and tidal volume are selected for the
mechanical breaths.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
2- PRESSURE VENTILATORS
The use of pressure ventilators is increasing in critical
care units.
A typical pressure mode delivers a selected gas
pressure to the patient early in inspiration, and
sustains the pressure throughout the inspiratory
phase.
By meeting the patients inspiratory flow demand
throughout inspiration, patient effort is reduced and
comfort increased.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Although pressure is consistent with these modes,
volume is not.
Volume will change with changes in resistance or
compliance,
Therefore, exhaled tidal volume is the variable to
monitor closely.
With pressure modes, the pressure level to be
delivered is selected, and with some mode options
(i.e., pressure controlled [PC], described later), rate
and inspiratory time are preset as well.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
3- HIGH-FREQUENCY VENTILATORS
High-frequency ventilators use small tidal volumes (1 to 3
mL/kg) at frequencies greater than 100 breaths/minute.
The high-frequency ventilator accomplishes oxygenation by
the diffusion of oxygen and carbon dioxide from high to low
gradients of concentration.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
This diffusion movement is increased if the kinetic energy of
the gas molecules is increased.
A high-frequency ventilator would be used to achieve lower
peak ventilator pressures, thereby lowering the risk of
barotrauma.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
CLASSIFICATION OF POSITIVE-PRESSURE
VENTILATORS:
Ventilators are classified according to how the inspiratory
phase ends. The factor which terminates the inspiratory cycle
reflects the machine type.
They are classified as:
1- Pressure cycled ventilator
2- Volume cycled ventilator
3- Time cycled ventilator
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
1- VOLUME-CYCLED VENTILATOR
Inspiration is terminated after a preset tidal volume has been
delivered by the ventilator.
The ventilator delivers a preset tidal volume (VT), and inspiration
stops when the preset tidal volume is achieved.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
2- PRESSURE-CYCLED VENTILATOR
In which inspiration is terminated when a specific airway pressure
has been reached.
The ventilator delivers a preset pressure; once this pressure is
achieved, end inspiration occurs.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
3- TIME-CYCLED VENTILATOR
In which inspiration is terminated when a preset inspiratory
time, has elapsed.
Time cycled machines are not used in adult critical care
settings. They are used in pediatric intensive care areas.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
VENTILATOR MODE
The way the machine ventilates the patient
How much the patient will participate in his own ventilatory
pattern.
Each mode is different in determining how much work of
breathing the patient has to do.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
©2021 ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Modes of Mechanical Ventilation
Controlled Mandatory Ventilation (CMV)
Asst-Control Mandatory Ventilation (ACV)
Synchronized Intermittent Mandatory Ventilation (SIMV)
Positive Expiratory End Pressure(PEEP)
Continuous Positive Airway Pressure (CPAP)
Pressure Support Ventilation (PSV)
MODES OF MECHANICAL VENTILATION
A- Volume Modes
B- Pressure Modes
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
A- VOLUME MODES
1- Assist-control (A/C)
2- Synchronized intermittent
mandatory ventilation (SIMV)
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
1- ASSIST CONTROL MODE A/C
The ventilator provides the patient with a pre-set tidal
volume at a pre-set rate .
The patient may initiate a breath on his own, but the
ventilator assists by delivering a specified tidal volume
to the patient. Client can initiate breaths that are
delivered at the preset tidal volume.
Client can breathe at a higher rate than the preset
number of breaths/minute
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
The total respiratory rate is determined by the number
of spontaneous inspiration initiated by the patient
plus the number of breaths set on the ventilator.
In A/C mode, a mandatory (or control) rate is
selected.
If the patient wishes to breathe faster, he or she can
trigger the ventilator and receive a full-volume breath.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Often used as initial mode of ventilation
When the patient is too weak to perform the work of
breathing (e.g., when emerging from anesthesia).
Disadvantages:
Hyperventilation,
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
2- SYNCHRONIZED INTERMITTENT
MANDATORY VENTILATION (SIMV)
The ventilator provides the patient with a pre-set number of
breaths/minute at a specified tidal volume and FiO2.
In between the ventilator-delivered breaths, the patient is able
to breathe spontaneously at his own tidal volume and rate
with no assistance from the ventilator.
However, unlike the A/C mode, any breaths taken above the
set rate are spontaneous breaths taken through the ventilator
circuit.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
The tidal volume of these breaths can vary drastically
from the tidal volume set on the ventilator, because
the tidal volume is determined by the patients
spontaneous effort.
Adding pressure support during spontaneous breaths
can minimize the risk of increased work of breathing.
Ventilators breaths are synchronized with the patient
spontaneous breathe.
( no fighting)
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Used to wean the patient from the mechanical ventilator.
Weaning is accomplished by gradually lowering the set rate
and allowing the patient to assume more work
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
B- PRESSURE MODES
1- Pressure-controlled ventilation (PCV)
2- Pressure-support ventilation (PSV)
3- Continuous positive airway pressure
(CPAP)
4- Positive end expiratory pressure (PEEP)
5- Noninvasive bilevel positive airway pressure
ventilation (BiPAP)
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
1- CONTROL MODE (CM)
CONTINUOUS MANDATORY VENTILATION ( CMV)
Ventilation is completely provided by the mechanical ventilator
with a preset tidal volume, respiratory rate and oxygen
concentration
Ventilator totally controls the patients 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
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
2- PRESSURE-CONTROLLED
VENTILATION MODE ( PCV)
The PCV mode is used
If compliance is decreased and the risk of barotrauma is high.
It is used when the patient has persistent oxygenation
problems despite a high FiO2and high levels of PEEP.
The inspiratory pressure level, respiratory rate, and
inspiratoryexpiratory (I:E) ratio must be selected.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
2- PRESSURE-CONTROLLED
VENTILATION MODE ( PCV)
In pressure controlled ventilation the breathing gas flows under
constant pressure into the lungs during the selected inspiratory
time.
The flow is highest at the beginning of inspiration( i.e when the
volume is lowest in the lungs).
As the pressure is constant the flow is initially high and then
decreases with increasing filling of the lungs.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
ADVANTAGES OF PRESSURE
LIMITATIONS ARE:
1- Reduction of peak pressure and therefore the
risk of barotruma and tracheal injury.
2- Effective ventilation
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Tidal volume varies with compliance and airway
resistance and must be closely monitored.
Sedation and the use of neuromuscular blocking
agents are frequently indicated, because any patient
ventilator asynchrony usually results in profound
drops in the SaO2.
This is especially true when inverse ratios are used.
The unnaturalfeeling of this mode often requires
muscle relaxants to ensure patientventilator
synchrony.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Inverse ratio ventilation (IRV) mode reverses this ratio
so that inspiratory time is equal to, or longer than,
expiratory time (1:1 to 4:1).
Inverse I:E ratios are used in conjunction with
pressure control to improve oxygenation by
expanding stiff alveoli by using longer distending
times, thereby providing more opportunity for gas
exchange and preventing alveolar collapse.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
As expiratory time is decreased, one must monitor for
the development of hyperinflation or auto-PEEP.
Regional alveolar overdistension and
barotrauma may occur owing to excessive total
PEEP.
When the PCV mode is used, the mean airway and
intrathoracic pressures rise, potentially resulting in a
decrease in cardiac output and oxygen delivery.
Therefore, the patients hemodynamic status must be
monitored closely.
Used to limit plateau pressures that can cause
barotrauma & Severe ARDS
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
3- 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 patients
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.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Indicated for patients with small spontaneous tidal volume and
difficult to wean patients.
Patient must initiate all pressure support breaths.
Pressure support ventilation may be combined with other
modes such as
SIMV or used alone for a spontaneously breathing patient.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
The patients effort determines the rate, inspiratory
flow, and tidal volume.
In PSV mode, the inspired tidal volume and respiratory
rate must be monitored closely to detect changes in
lung compliance.
It is a mode used primarily for weaning from
mechanical ventilation.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
4- CONTINUOUS POSITIVE AIRWAY
PRESSURE (CPAP)
Constant positive airway pressure during spontaneous breathing
CPAP allows the nurse to observe the ability of the patient to breathe
spontaneously while still on the ventilator.
CPAP can be used for intubated and nonintubated patients.
It may be used as a weaning mode and for nocturnal ventilation
(nasal or mask CPAP)
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
5- 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.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
USES OF CPAP & PEEP
Prevent atelactasis or collapse of alveoli
Treat atelactasis or collapse of alveoli
Improve gas exchange & oxygenation
Treat hypoxemia refractory to oxygen therapy.(prevent oxygen
toxicity
Treat pulmonary edema ( pressure help expulsion of fluids from
alveoli
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
6- NONINVASIVE BILATERAL 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.
The system allows the clinician 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).
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
COMMON VENTILATOR SETTINGS
PARAMETERS/ CONTROLS
Fraction of inspired oxygen (FIO2)
Tidal Volume (VT)
Peak Flow/ Flow Rate
Respiratory Rate/ Breath Rate / Frequency ( F)
Minute Volume (VE)
I:E Ratio (Inspiration to Expiration Ratio)
Sigh
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
FRACTION OF INSPIRED OXYGEN (FIO2)
The percent of oxygen concentration that the patient
is receiving from the ventilator. (Between 21% &
100%)
(room air has 21% oxygen content).
Initially a patient is placed on a high level of FIO2
(60% or higher).
Subsequent changes in FIO2are based on ABGs and
the SaO2.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Adult patients the initial FiO2may be set at 100% until arterial
blood gases can document adequate oxygenation.
An FiO2 of 100% for an extended period of time can be
dangerous ( oxygen toxicity) but it can protect against
hypoxemia
For infants, and especially in premature infants, high levels of
FiO2(>60%) should be avoided.
Usually the FIO2is adjusted to maintain an SaO2 of greater
than 90% (roughly equivalent to a PaO2>60 mm Hg).
Oxygen toxicity is a concern when an FIO2of greater than
60% is required for more than 25 hours
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Signs and symptoms of oxygen toxicity :-
1- Flushed face
2- Dry cough
3- Dyspnea
4- Chest pain
5- Tightness of chest
6- Sore throat
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
TIDAL VOLUME (VT)
The volume of air delivered to a patient during a
ventilator breath.
The amount of air inspired and expired with each
breath.
Usual volume selected is between 5 to 15 ml/ kg
body weight)
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
In the volume ventilator, Tidal volumes of 10 to 15
mL/kg of body weight were traditionally used.
the large tidal volumes may lead to (volutrauma)
aggravate the damage inflicted on the lungs
For this reason, lower tidal volume targets (6 to 8
mL/kg) are now recommended.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
PEAK FLOW/ FLOW RATE
The speed of delivering air per unit of time, and is expressed
in liters per minute.
The higher the flow rate, the faster peak airway pressure is
reached and the shorter the inspiration;
The lower the flow rate, the longer the inspiration.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
RESPIRATORY RATE/ BREATH
RATE / FREQUENCY ( F)
The number of breaths the ventilator will
deliver/minute (10-16 b/m).
Total respiratory rate equals patient rate plus
ventilator rate.
The nurse double-checks the functioning of the
ventilator by observing the patients respiratory rate.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
For adult patients and older children:-
With COPD
A reduced tidal volume
A reduced respiratory rate
For infants and younger children:-
A small tidal volume
Higher respiratory rate
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
MINUTE VOLUME (VE)
The volume of expired air in one minute .
Respiratory rate times tidal volume equals minute
ventilation
VE = (VT x F)
In special cases, hypoventilation or hyperventilation
is desired
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
In a patient with head injury,
Respiratory alkalosis may be required to promote
cerebral vasoconstriction, with a resultant decrease in
ICP.
In this case, the tidal volume and respiratory rate are
increased
( hyperventilation) to achieve the desired alkalotic
pH by manipulating the PaCO2.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
In a patient with COPD
Baseline ABGs reflect an elevated PaCO2should not
hyperventilated. Instead, the goal should be
restoration of the baseline PaCO2.
These patients usually have a large carbonic acid
load, and lowering their carbon dioxide levels rapidly
may result in seizures.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
I:E RATIO (INSPIRATION TO
EXPIRATION RATIO):-
The ratio of inspiratory time to expiratory time
during a breath (Usually = 1:2)
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
SIGH
A deep breath.
A breath that has a greater volume than the tidal volume.
It provides hyperinflation and prevents atelectasis.
Sigh volume :------------------Usual volume is 1.5 2 times tidal volume.
Sigh rate/ frequency :---------Usual rate is 4 to 8 times an hour.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
PEAK AIRWAY PRESSURE:-
In adults if the peak airway pressure is persistently above 45
cmH2O, the risk of barotrauma is increased and efforts should
be made to try to reduce the peak airway pressure.
In infants and children it is unclear what level of peak pressure
may cause damage. In general, keeping peak pressures below
30 is desirable.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
PRESSURE LIMIT
On volume-cycled ventilators, the pressure limit dial
limits the highest pressure allowed in the ventilator
circuit.
Once the high pressure limit is reached, inspiration is
terminated.
Therefore, if the pressure limit is being constantly
reached, the designated tidal volume is not being
delivered to the patient.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
SENSITIVITY( TRIGGER SENSITIVITY)
The sensitivity function controls the amount of patient
effort needed to initiate an inspiration
Increasing the sensitivity (requiring less negative
force) decreases the amount of work the patient must
do to initiate a ventilator breath.
Decreasing the sensitivity increases the amount of
negative pressure that the patient needs to initiate
inspiration and increases the work of breathing.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
ENSURING HUMIDIFICATION AND
THERMOREGULATION
All air delivered by the ventilator passes through the water in
the humidifier, where it is warmed and saturated.
Humidifier temperatures should be kept close to body
temperature 35 ºC- 37ºC.
In some rare instances (severe hypothermia), the air
temperatures can be increased.
The humidifier should be checked for adequate water levels
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
An empty humidifier contributes to drying the airway,
often with resultant dried secretions, mucus plugging
and less ability to suction out secretions.
Humidifier should not be overfilled as this may
increase circuit resistance and interfere with
spontaneous breathing.
As air passes through the ventilator to the patient,
water condenses in the corrugated tubing. This
moisture is considered contaminated and must be
drained into a receptacle and not back into the sterile
humidifier.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
If the water is allowed to build up, resistance is
developed in the circuit and PEEP is generated. In
addition, if moisture accumulates near the
endotracheal tube, the patient can aspirate the water.
The nurse and respiratory therapist jointly are
responsible for preventing this condensation buildup.
The humidifier is an ideal medium for bacterial
growth.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
VENTILATOR ALARMS:-
Mechanical ventilators comprise audible and visual
alarm systems, which act as immediate warning
signals to altered ventilation.
Alarm systems can be categorized according to
volume and pressure (high and low).
High-pressure alarms warn of rising pressures.
Low-pressure alarms warn of disconnection of the
patient from the ventilator or circuit leaks.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
COMPLICATIONS
OF MECHANICAL VENTILATION:-
I- Airway Complications,
II-Mechanical complications,
III-Physiological Complications,
IV-Artificial Airway Complications.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
I- AIRWAY COMPLICATIONS
1- Aspiration
2- Decreased clearance of secretions
3- Nosocomial or ventilator-acquired
pneumonia
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
II- MECHANICAL COMPLICATIONS
1- Hypoventilation with atelectasis with respiratory
acidosis or hypoxemia.
2- Hyperventilation with hypocapnia and respiratory alkalosis
3- Barotrauma
a- Closed pneumothorax,
b- Tension pneumothorax,
c- Pneumomediastinum,
d- Subcutaneous emphysema.
4- Alarm turned off
5- Failure of alarms or ventilator
6- Inadequate nebulization or humidification
7- Overheated inspired air, resulting in hyperthermia
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
III- PHYSIOLOGICAL COMPLICATIONS
1- Fluid overload with humidified air and
sodium chloride (NaCl) retention
2- Depressed cardiac function and
hypotension
3- Stress ulcers
4- Paralytic ileus
5- Gastric distension
6- Starvation
7- Dyssynchronous breathing pattern
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
IV- ARTIFICIAL AIRWAY COMPLICATIONS
A- COMPLICATIONS RELATED TO
ENDOTRACHEAL TUBE:-
1- Tube kinked or plugged
2- Rupture of piriform sinus
3- Tracheal stenosis or tracheomalacia
4- Mainstem intubation with contralateral lung
atelectasis
5- Cuff failure
6- Sinusitis
7- Otitis media
8- Laryngeal edema
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
B- COMPLICATIONS RELATED TO
TRACHEOSTOMY TUBE:-
1- Acute hemorrhage at the site
2- Air embolism
3- Aspiration
4- Tracheal stenosis
5- Erosion into the innominate artery with exsanguination
6- Failure of the tracheostomy cuff
7- Laryngeal nerve damage
8- Obstruction of tracheostomy tube
9- Pneumothorax
10-Subcutaneous and mediastinal emphysema
11-Swallowing dysfunction
12-Tracheoesophageal fistula
13-Infection
14-Accidental decannulation with loss of airway
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
NURSING CARE OF PATIENTS ON
MECHANICAL VENTILATION
Assessment:
1- Assess the patient
2- Assess the artificial airway (tracheostomy
or endotracheal tube)
3- Assess the ventilator
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
NURSING INTERVENTIONS
1-Maintain airway patency & oxygenation
2- Promote comfort
3- Maintain fluid & electrolytes balance
4- Maintain nutritional state
5- Maintain urinary & bowel elimination
6- Maintain eye , mouth and cleanliness and integrity:-
7- Maintain mobility/ musculoskeletal function:-
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
NURSING INTERVENTIONS
8- Maintain safety:-
9- Provide psychological support
10-Facilitate communication
11-Provide psychological support & information to family
12-Responding to ventilator alarms /Troublshooting
ventilator alarms
13-Prevent nosocomial infection
14-Documentation
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
RESPONDING TO ALARMS
If an alarm sounds, respond immediately because the
problem could be serious.
Assess the patient first, while you silence the alarm.
If you can not quickly identify the problem, take the
patient off the ventilator and ventilate him with a
resuscitation bag connected to oxygen source until the
physician arrives.
A nurse or respiratory therapist must respond to every
ventilator alarm.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Alarms must never be ignored or
disarmed.
Ventilator malfunction is a potentially
serious problem. Nursing or respiratory
therapists perform ventilator checks every
2 to 4 hours, and recurrent alarms may
alert the clinician to the possibility of an
equipment-related issue.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
When device malfunction is suspected, a
second person manually ventilates the
patient while the nurse or therapist looks
for the cause.
If a problem cannot be promptly corrected
by ventilator adjustment, a different
machine is procured so the ventilator in
question can be taken out of service for
analysis and repair by technical staff.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
CAUSES OF VENTILATOR ALARMS
High pressure alarm
Increased secretions
Kinked ventilator tubing or endotracheal tube (ETT)
Patient biting the ETT
Water in the ventilator tubing.
ETT advanced into right mainstem bronchus.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Low pressure alarm
Disconnected tubing
A cuff leak
A hole in the tubing (ETT or ventilator tubing)
A leak in the humidifier
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Oxygen alarm
The oxygen supply is insufficient or is not
properly connected.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
High respiratory rate alarm
Episodes of tachypnea,
Anxiety,
Pain,
Hypoxia,
Fever.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
-
1- T-PIECE TRIAL
It consists of removing the patient from the ventilator
and having him / her breathe spontaneously on a T-
tube connected to oxygen source.
During T-piece weaning, periods of ventilator support
are alternated with spontaneous breathing.
The goal is to progressively increase the time spent
off the ventilator.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
2-SYNCHRONIZED INTERMITTENT MANDATORY
VENTILATION ( SIMV) WEANING
SIMV is the most common method of weaning.
It consists of gradually decreasing the number of
breaths delivered by the ventilator to allow the
patient to increase number of spontaneous breaths
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
3-CONTINUOUS POSITIVE AIRWAY PRESSURE (
CPAP) WEANING
When placed on CPAP, the patient does all the work
of breathing without the aid of a back up rate or tidal
volume.
No mandatory (ventilator-initiated) breaths are
delivered in this mode i.e. all ventilation is
spontaneously initiated by the patient.
Weaning by gradual decrease in pressure value
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
4- PRESSURE SUPPORT VENTILATION (PSV)
WEANING
The patient must initiate all pressure support breaths.
During weaning using the PSV mode the level of pressure
support is gradually decreased based on the patient
maintaining an adequate tidal volume (8 to 12 mL/kg) and a
respiratory rate of less than 25 breaths/minute.
PSV weaning is indicated for :-
-Difficult to wean patients
-Small spontaneous tidal volume.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
WEANING READINESS CRITERIA
Awake and alert
Hemodynamically stable, adequately resuscitated,
and not requiring vasoactive support
Arterial blood gases (ABGs) normalized or at
patients baseline
- PaCO2acceptable
- PH of 7.35 7.45
- PaO2> 60 mm Hg ,
- SaO2>92%
- FIO2≤40%
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Positive end-expiratory pressure (PEEP) 5 cm H2O
F < 25 / minute
Vt 5 ml / kg
VE 5- 10 L/m (f x Vt)
VC > 10-15 ml / kg
PEP (positive expiratory pressure) > - 20 cm H2O ( indicates
patients ability to take a deep breath & cough),
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
ROLE OF NURSE BEFORE WEANING:-
1- Ensure that indications for the implementation of Mechanical ventilation
have improved
2- Ensure that all factors that may interfere with successful weaning are
corrected:-
- Acid-base abnormalitie
- Fluid imbalance
- Electrolyte abnormalities
- Infection
- Fever
- Anemia
- Hyperglycemia
- Protein
- Sleep deprivation
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
ROLE OF NURSE BEFORE WEANING:-
3- Assess readiness for weaning
4- Ensure that the weaning criteria / parameters are
met.
5- Explain the process of weaning to the patient and offer
reassurance to the patient.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
ROLE OF NURSE DURING WEANING:-
1- Wean only during the day.
2- Remain with the patient during
initiation of weaning.
3- Instruct the patient to relax and breathe
normally.
4- Monitor the respiratory rate, vital signs,
ABGs, diaphoresis and use of accessory
muscles frequently.
If signs of fatigue or respiratory distress develop.
Discontinue weaning trials.
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
SIGNS OF WEANING INTOLERANCE CRITERIA
Diaphoresis
Dyspnea & Labored respiratory pattern
Increased anxiety ,Restlessness, Decrease in level of
consciousness
Dysrhythmia,Increase or decrease in heart rate of >
20 beats /min. or heart rate > 110b/m,Sustained
heart rate >20% higher or lower than baseline
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
Increase or decrease in blood pressure of > 20 mm Hg
Systolic blood pressure >180 mm Hg or <90 mm Hg
Increase in respiratory rate of > 10 above baseline or >
30
Sustained respiratory rate greater than 35
breaths/minute
Tidal volume ≤5 mL/kg, Sustained minute ventilation
<200 mL/kg/minute
SaO2 < 90%, PaO2 < 60 mmHg, decrease in PH of <
7.35.
Increase in PaCO2
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
ROLE OF NURSE AFTER WEANING
1- Ensure that extubation criteria are met
2- Decanulate or extubat
2- Documeantation
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
©2021 DR ROHIT BHASKAR PT HTTPS://WWW.PT-PEDIA.COM/
THANK YOU
ResearchGate has not been able to resolve any citations for this publication.
ResearchGate has not been able to resolve any references for this publication.