Mechanical Mechanical VentilationVentilation

Dr. Abdul-Monim BatihaDr. Abdul-Monim Batiha

Assistant ProfessorAssistant ProfessorCritical Care NursingCritical Care Nursing

• Mechanical Ventilation is Mechanical Ventilation is ventilation of the lungs by ventilation of the lungs by artificial means usually by a artificial means usually by a ventilator. ventilator.

• A ventilator delivers gas to the A ventilator delivers gas to the lungs with either negative or lungs with either negative or positive pressure.positive pressure.

PurposesPurposes::

• To maintain or improve To maintain or improve ventilation, & tissue ventilation, & tissue oxygenation.oxygenation.

• To decrease the work of To decrease the work of breathing & improve patientbreathing & improve patient’’s s comfort.comfort.

IndicationsIndications::

1- 1- Acute respiratory failure due to:Acute respiratory failure due to:

• Mechanical failureMechanical failure, includes neuromuscular , includes neuromuscular diseases as Myasthenia Gravis, Guillain-Barré diseases as Myasthenia Gravis, Guillain-Barré Syndrome, and Poliomyelitis (failure of the Syndrome, and Poliomyelitis (failure of the normal respiratory neuromuscular system)normal respiratory neuromuscular system)

• Musculoskeletal abnormalitiesMusculoskeletal abnormalities, such as chest wall , such as chest wall trauma (flail chest)trauma (flail chest)

• Infectious diseasesInfectious diseases of the lung such as pneumonia, of the lung such as pneumonia, tuberculosis.tuberculosis.

2-2- Abnormalities of pulmonary gas exchange Abnormalities of pulmonary gas exchange as in:as in:

• Obstructive lung diseaseObstructive lung disease in the form of in the form of asthma, chronic bronchitis or emphysema.asthma, chronic bronchitis or emphysema.

• Conditions such as pulmonary edema, Conditions such as pulmonary edema, atelectasis, pulmonary fibrosis.atelectasis, pulmonary fibrosis.

• Patients who has received Patients who has received general general anesthesiaanesthesia as well as as well as post cardiac arrestpost cardiac arrest patients often require ventilatory support patients often require ventilatory support until they have recovered from the effects until they have recovered from the effects of the anesthesia or the insult of an arrest.of the anesthesia or the insult of an arrest.

Criteria for institution of Criteria for institution of ventilatory supportventilatory support::

ParametersParameters Ventilation Ventilation indicatedindicated

Normal Normal rangerange

A- Pulmonary functionA- Pulmonary function

studiesstudies::

• Respiratory rate Respiratory rate

(breaths/min).(breaths/min).

• Tidal volume (ml/kgTidal volume (ml/kg

body wt)body wt)

• Vital capacity (ml/kg Vital capacity (ml/kg

body wt)body wt)

• Maximum InspiratoryMaximum Inspiratory

Force (cm HOForce (cm HO2) )

> >3535

< <55

< <1515

-<-<2020

10-2010-20

5-75-7

65-7565-75

75-10075-100

Criteria for institution of Criteria for institution of ventilatory supportventilatory support::

ParametersParametersVentilation Ventilation indicatedindicated

Normal Normal rangerange

B- Arterial bloodB- Arterial blood

GasesGases

• PHPH

• PaOPaO2 (mmHg) (mmHg)

• PaCOPaCO2 (mmHg) (mmHg)

< <7.257.25

< <6060

> >5050

7.35-7.457.35-7.45

75-10075-100

35-4535-45

Types of Mechanical Types of Mechanical ventilatorsventilators::

• Negative-pressure ventilators Negative-pressure ventilators

• Positive-pressure ventilators. Positive-pressure ventilators.

Negative-Pressure Negative-Pressure VentilatorsVentilators• Early negative-pressure Early negative-pressure

ventilators were known as ventilators were known as ““iron iron lungs.lungs.””

• The patientThe patient’’s body was encased in s body was encased in an iron cylinder and negative an iron cylinder and negative pressure was generated .pressure was generated .

• The iron lung are still occasionally The iron lung are still occasionally used today. used today.

• Intermittent short-term negative-Intermittent short-term negative-pressure ventilation is sometimes pressure ventilation is sometimes used in patients with chronic diseases. used in patients with chronic diseases.

• The use of negative-pressure The use of negative-pressure ventilators is restricted in clinical ventilators is restricted in clinical practice, however, because practice, however, because they limit they limit positioning and movement and they positioning and movement and they lack adaptability to large or small lack adaptability to large or small body torsos (chests) .body torsos (chests) .

• Our focus will be on the positive-Our focus will be on the positive-pressure ventilators.pressure ventilators.

Positive-pressure Positive-pressure ventilatorsventilators

• Positive-pressure ventilators Positive-pressure ventilators deliver gas to the patient under deliver gas to the patient under positive-pressure, during the positive-pressure, during the inspiratory phase.inspiratory phase.

Types of Positive-Pressure Types of Positive-Pressure VentilatorsVentilators

1- 1- Volume Ventilators.Volume Ventilators.

2-2- Pressure Ventilators Pressure Ventilators

3-3- High-Frequency Ventilators High-Frequency Ventilators

• The volume ventilator is The volume ventilator is commonly commonly usedused in critical care settings. in critical care settings.

• The basic principle of this ventilator is The basic principle of this ventilator is that that a designated volume of air is a designated volume of air is delivered with each breath.delivered with each breath.

• The amount of The amount of pressurepressure required to required to deliver the set volume deliver the set volume depends on :-depends on :-

- Patient- Patient’’s lung compliance s lung compliance - Patient- Patient––ventilator resistance ventilator resistance

factors. factors.

1-1- Volume Ventilators Volume Ventilators

• Therefore, Therefore, peak inspiratory peak inspiratory pressure pressure (PIP )(PIP ) must be monitored must be monitored in volume modes because it varies in volume modes because it varies from breath to breath. from breath to breath.

• With this mode of ventilation, a With this mode of ventilation, a respiratory rate, inspiratory time, respiratory rate, inspiratory time, and tidal volume are selected for and tidal volume are selected for the mechanical breaths.the mechanical breaths.

• The use of pressure ventilators The use of pressure ventilators is is increasing increasing in critical care units. in critical care units.

• A typical pressure mode A typical pressure mode delivers a delivers a selected gas pressure to the patient selected gas pressure to the patient early in inspiration, and sustains the early in inspiration, and sustains the pressure throughout the inspiratory pressure throughout the inspiratory phase. phase.

• By meeting the patientBy meeting the patient’’s inspiratory flow s inspiratory flow demand throughout inspiration, demand throughout inspiration, patient patient effort is reduced and comfort increased.effort is reduced and comfort increased.

2-2- Pressure Ventilators Pressure Ventilators

• Although Although pressure is consistentpressure is consistent with with these modes, volume is not. these modes, volume is not.

• Volume will change with changes in Volume will change with changes in resistance or compliance, resistance or compliance,

• Therefore, Therefore, exhaled tidal volume is the exhaled tidal volume is the variable to monitor closely. variable to monitor closely.

• With pressure modes, With pressure modes, the pressure the pressure level to be delivered is selected, and level to be delivered is selected, and with some mode optionswith some mode options (i.e., (i.e., pressure controlled [PC], described pressure controlled [PC], described later), later), rate and inspiratory time are rate and inspiratory time are preset as well.preset as well.

33 - -High-Frequency High-Frequency VentilatorsVentilators

• High-frequency ventilators High-frequency ventilators use use small tidal volumes (1 to 3 small tidal volumes (1 to 3 mL/kg) at frequencies greater mL/kg) at frequencies greater than 100 breaths/minute. than 100 breaths/minute.

• The high-frequency ventilator The high-frequency ventilator accomplishes oxygenation by the accomplishes oxygenation by the diffusion of oxygen and carbon diffusion of oxygen and carbon dioxide from high to low dioxide from high to low gradients of concentration.gradients of concentration.

• This diffusion movement is This diffusion movement is increased if the kinetic energy of increased if the kinetic energy of the gas molecules is increased.the gas molecules is increased.

• A high-frequency ventilator A high-frequency ventilator would be used would be used to achieve lower to achieve lower peak ventilator pressures, peak ventilator pressures, thereby lowering the risk of thereby lowering the risk of barotraumabarotrauma..

Classification of positive-Classification of positive-pressure ventilatorspressure ventilators::

• Ventilators are classified according to Ventilators are classified according to how the inspiratory phase ends.how the inspiratory phase ends. The The factor which terminates the inspiratory factor which terminates the inspiratory cycle reflects the machine type. cycle reflects the machine type.

• They are classified as:They are classified as:

1- 1- Pressure cycled Pressure cycled ventilatorventilator

2-2- Volume cycled Volume cycled ventilatorventilator

3- 3- Time cycled ventilatorTime cycled ventilator

11-- Volume-cycled Volume-cycled ventilatorventilator

• Inspiration is terminated after a Inspiration is terminated after a preset tidal volume has been preset tidal volume has been delivered by the ventilator. delivered by the ventilator.

• The ventilator delivers a preset The ventilator delivers a preset tidal volume (VT), and tidal volume (VT), and inspiration stops when the inspiration stops when the preset tidal volume is achieved.preset tidal volume is achieved.

22-- Pressure-cycled Pressure-cycled ventilatorventilator

• In which inspiration is In which inspiration is terminated when a specific terminated when a specific airway pressure has been airway pressure has been reached. reached.

• The ventilator delivers a preset The ventilator delivers a preset pressure; once this pressure is pressure; once this pressure is achieved, end inspiration occurs.achieved, end inspiration occurs.

33 - -Time-cycled ventilatorTime-cycled ventilator

• In which inspiration is In which inspiration is terminated when a preset terminated when a preset inspiratory time, has elapsed. inspiratory time, has elapsed.

• Time cycled machines are not Time cycled machines are not used in adult critical care used in adult critical care settings. They are settings. They are used in used in pediatric intensive care areas.pediatric intensive care areas.

Ventilator modeVentilator mode • The way the machine ventilates the The way the machine ventilates the

patient patient

• How much the patient will How much the patient will participate in his own ventilatory participate in his own ventilatory pattern. pattern.

• Each mode is different in Each mode is different in determining how much work of determining how much work of breathing the patient has to do.breathing the patient has to do.

Modes of Mechanical Modes of Mechanical VentilationVentilation

A- A- Volume ModesVolume Modes

B- B- Pressure ModesPressure Modes

A- Volume ModesA- Volume Modes

1- 1- Assist-control Assist-control (A/C)(A/C)

2- 2- Synchronized intermittent Synchronized intermittent

mandatory ventilation mandatory ventilation (SIMV)(SIMV)

1- Assist Control Mode 1- Assist Control Mode A/CA/C

• The ventilator provides the patient with The ventilator provides the patient with a pre-set tidal volume at a pre-set rate .a pre-set tidal volume at a pre-set rate .

• The patient may The patient may initiate a breath on his initiate a breath on his ownown, but the , but the ventilator assists by ventilator assists by delivering a specified tidal volume to delivering a specified tidal volume to the patient.the patient. Client can initiate breaths Client can initiate breaths that are delivered at the preset tidal that are delivered at the preset tidal volume.volume.

• Client can breathe at a higher rate than Client can breathe at a higher rate than the preset number of breaths/minutethe preset number of breaths/minute

• The The total respiratory ratetotal respiratory rate is is determined by determined by the number of the number of spontaneous inspiration initiated by spontaneous inspiration initiated by the patientthe patient plus plus the number of the number of breaths set on the ventilator.breaths set on the ventilator.

• In A/C mode, a mandatory (or In A/C mode, a mandatory (or ““controlcontrol””) rate is selected.) rate is selected.

• If the patient wishes to breathe If the patient wishes to breathe faster, he or she can faster, he or she can trigger the trigger the ventilator and receive a full-volume ventilator and receive a full-volume breath.breath.

• Often used as initial mode of Often used as initial mode of ventilationventilation

• When the patient is too weak to When the patient is too weak to perform the work of breathing perform the work of breathing (e.g., when emerging from (e.g., when emerging from anesthesia).anesthesia).

Disadvantages:Disadvantages:

• Hyperventilation, Hyperventilation,

22-- Synchronized Intermittent Synchronized Intermittent Mandatory Ventilation Mandatory Ventilation (SIMV)(SIMV)• The ventilator provides the patient with a The ventilator provides the patient with a

pre-set number of breaths/minute at a pre-set number of breaths/minute at a specified tidal volume and FiOspecified tidal volume and FiO2. .

• In between the ventilator-delivered breathsIn between the ventilator-delivered breaths, , the patient is able to the patient is able to breathe spontaneously breathe spontaneously at his own tidal volume and rateat his own tidal volume and rate with no with no assistance from the ventilator.assistance from the ventilator.

• However, unlike the A/C mode, However, unlike the A/C mode, any breaths any breaths taken above the set rate are spontaneous taken above the set rate are spontaneous breaths taken through the ventilator circuit.breaths taken through the ventilator circuit.

• The tidal volume of these breaths can The tidal volume of these breaths can vary drastically from the tidal volume vary drastically from the tidal volume set on the ventilatorset on the ventilator, because the tidal , because the tidal volume is determined by the volume is determined by the patientpatient’’s s spontaneous effort. spontaneous effort.

• Adding pressure supportAdding pressure support during during spontaneous breaths can spontaneous breaths can minimize the minimize the risk of increased work of breathing. risk of increased work of breathing.

• Ventilators breaths are Ventilators breaths are synchronizedsynchronized with the patient spontaneous breathe.with the patient spontaneous breathe.

( no fighting)( no fighting)

• Used to wean the patient from Used to wean the patient from the mechanical ventilator.the mechanical ventilator.

• WeaningWeaning is accomplished by is accomplished by gradually lowering the set rate gradually lowering the set rate and allowing the patient to and allowing the patient to assume more workassume more work

B- Pressure ModesB- Pressure Modes1-1- Pressure-controlled ventilation Pressure-controlled ventilation (PCV)(PCV) 2-2- Pressure-support ventilation Pressure-support ventilation (PSV)(PSV)

3-3- Continuous positive airway pressure Continuous positive airway pressure

(CPAP)(CPAP)

4- 4- Positive end expiratory pressure Positive end expiratory pressure (PEEP) (PEEP)

5-5- Noninvasive bilevel positive airway Noninvasive bilevel positive airway pressure ventilation pressure ventilation (BiPAP)(BiPAP)

1- Control Mode (CM)1- Control Mode (CM) Continuous Mandatory Continuous Mandatory VentilationVentilation ( CMV)( CMV)• Ventilation is completely provided by the Ventilation is completely provided by the

mechanical ventilator with mechanical ventilator with a preset tidal a preset tidal volume, respiratory rate and oxygen volume, respiratory rate and oxygen concentrationconcentration

• Ventilator Ventilator totally controls the patienttotally controls the patient’’s s ventilationventilation i.e. the ventilator initiates and i.e. the ventilator initiates and controls both the volume delivered and the controls both the volume delivered and the frequency of breath.frequency of breath.

• Client does not breathe spontaneously.Client does not breathe spontaneously.

• Client can not initiate breatheClient can not initiate breathe

22 - -Pressure-Controlled Pressure-Controlled Ventilation Mode Ventilation Mode ( PCV)( PCV)• The PCV mode is used The PCV mode is used

– If If compliance is decreasedcompliance is decreased and and the risk of the risk of barotrauma is high.barotrauma is high.

– It is used when the patient has It is used when the patient has persistent persistent oxygenation problemsoxygenation problems despite a high FiO despite a high FiO2 and high levels of PEEP. and high levels of PEEP.

• The inspiratory pressure level, respiratory The inspiratory pressure level, respiratory rate, and inspiratoryrate, and inspiratory––expiratory (I:E) ratio expiratory (I:E) ratio must be selected.must be selected.

22 - -Pressure-Controlled Pressure-Controlled Ventilation Mode Ventilation Mode ( PCV)( PCV)• In pressure controlled ventilation the In pressure controlled ventilation the breathing gas flows under constant breathing gas flows under constant pressure into the lungs during the pressure into the lungs during the selected inspiratory time.selected inspiratory time.

• The flow is highest at the beginning of The flow is highest at the beginning of inspiration( i.e when the volume is inspiration( i.e when the volume is lowest in the lungs).lowest in the lungs).

• As the pressure is constant the flow is As the pressure is constant the flow is initially high and then decreases with initially high and then decreases with increasing filling of the lungs.increasing filling of the lungs.

• Like volume controlled ventilation Like volume controlled ventilation PCV is time controlled.PCV is time controlled.

Advantages of pressure Advantages of pressure limitations arelimitations are::

• 1- reduction of peak pressure and 1- reduction of peak pressure and therefore the risk of barotruma and therefore the risk of barotruma and tracheal injury. tracheal injury.

• 2- effective ventilation.2- effective ventilation.

• Improve gas exchange Improve gas exchange

• Tidal volume varies with compliance and Tidal volume varies with compliance and airway resistance and must be closely airway resistance and must be closely monitoredmonitored. .

• Sedation and the use of neuromuscular Sedation and the use of neuromuscular blocking agentsblocking agents are frequently are frequently indicated, because any patientindicated, because any patient––ventilator asynchrony usually results in ventilator asynchrony usually results in profound drops in the SaOprofound drops in the SaO2. .

• This is especially true when inverse This is especially true when inverse ratios are used. The ratios are used. The ““unnaturalunnatural”” feeling feeling of this mode often requires muscle of this mode often requires muscle relaxants to ensure patientrelaxants to ensure patient––ventilator ventilator synchrony. synchrony.

• Inverse ratio ventilation (IRV) mode Inverse ratio ventilation (IRV) mode reverses this ratio so that reverses this ratio so that inspiratory inspiratory time is equal to, or longer than, time is equal to, or longer than, expiratory time (1:1 to 4:1). expiratory time (1:1 to 4:1).

• Inverse I:E ratios are used in Inverse I:E ratios are used in conjunction with pressure control conjunction with pressure control to to improve oxygenationimprove oxygenation by expanding by expanding stiff alveoli by using longer stiff alveoli by using longer distending times, thereby providing distending times, thereby providing more opportunity for gas exchange more opportunity for gas exchange and preventing alveolar collapse.and preventing alveolar collapse.

• As expiratory time is decreased, one As expiratory time is decreased, one must monitor for the development of must monitor for the development of hyperinflation or auto-PEEP. Regional hyperinflation or auto-PEEP. Regional alveolar overdistension andalveolar overdistension and

barotrauma may occur owing to barotrauma may occur owing to excessive total PEEP.excessive total PEEP.

• When the PCV mode is used, the mean When the PCV mode is used, the mean airway and intrathoracic pressures airway and intrathoracic pressures rise, potentially resulting in a decrease rise, potentially resulting in a decrease in cardiac output and oxygen delivery. in cardiac output and oxygen delivery. Therefore, Therefore, the patientthe patient’’s hemodynamic s hemodynamic status must be monitored closely.status must be monitored closely.

• Used to limit plateau pressures that Used to limit plateau pressures that can cause barotrauma & Severe ARDScan cause barotrauma & Severe ARDS

33 - -Pressure Support Ventilation Pressure Support Ventilation

( PSV)( PSV)• The patient breathes spontaneously The patient breathes spontaneously

while the ventilator while the ventilator applies a pre-applies a pre-determined amount of positive pressure determined amount of positive pressure to the airways upon inspiration.to the airways upon inspiration.

• Pressure support ventilation augments Pressure support ventilation augments patientpatient’’s spontaneous breaths with s spontaneous breaths with positive pressure boost during positive pressure boost during inspirationinspiration i.e. assisting each i.e. assisting each spontaneous inspiration.spontaneous inspiration.

• Helps to overcome airway resistance Helps to overcome airway resistance and and reducing the work of breathingreducing the work of breathing..

• Indicated for patients with Indicated for patients with small small spontaneous tidal volume and spontaneous tidal volume and difficult to wean patients.difficult to wean patients.

• Patient Patient must initiate all pressure must initiate all pressure support breaths.support breaths.

• Pressure support ventilation may Pressure support ventilation may be be combined with other modes combined with other modes such assuch as

SIMVSIMV or or used alone for a used alone for a spontaneously breathing patient.spontaneously breathing patient.

• The patientThe patient’’s effort determines the s effort determines the rate, inspiratory flow, and tidal rate, inspiratory flow, and tidal volume. volume.

• In PSV mode, In PSV mode, the inspired tidal the inspired tidal volume and respiratory rate must volume and respiratory rate must be monitored closelybe monitored closely to detect to detect changes in lung compliance. changes in lung compliance.

• It is a mode It is a mode used primarily for used primarily for weaning from mechanical weaning from mechanical ventilation.ventilation.

• Constant positive airway pressureConstant positive airway pressure during during spontaneous breathingspontaneous breathing

• CPAP allows the nurse to observe the ability of the CPAP allows the nurse to observe the ability of the patient to breathe spontaneously while still on the patient to breathe spontaneously while still on the ventilator.ventilator.

• CPAP can be used CPAP can be used for intubated and nonintubated for intubated and nonintubated patients.patients.

• It may be used as It may be used as a weaning modea weaning mode and for and for nocturnal nocturnal ventilationventilation (nasal or mask CPAP) (nasal or mask CPAP)

44 - -Continuous Positive Continuous Positive Airway Airway Pressure (CPAP) Pressure (CPAP)

55 - -Positive end expiratoryPositive end expiratory pressure (PEEP) pressure (PEEP)

• Positive pressure applied at the Positive pressure applied at the end of expiration during end of expiration during mandatory \ ventilator breathmandatory \ ventilator breath

• positive end-expiratory pressure positive end-expiratory pressure with positive-pressure (machine) with positive-pressure (machine) breaths. breaths.

Uses of CPAP & PEEPUses of CPAP & PEEP• Prevent atelactasis or collapse of Prevent atelactasis or collapse of

alveolialveoli

• Treat atelactasis or collapse of alveoliTreat atelactasis or collapse of alveoli • Improve gas exchange & oxygenation Improve gas exchange & oxygenation • Treat hypoxemia refractory to oxygen Treat hypoxemia refractory to oxygen

therapy.(prevent oxygen toxicitytherapy.(prevent oxygen toxicity

• Treat pulmonary edema ( pressure Treat pulmonary edema ( pressure help expulsion of fluids from alveoli help expulsion of fluids from alveoli

66 - -Noninvasive Bilateral Positive Noninvasive Bilateral Positive Airway Pressure Ventilation Airway Pressure Ventilation (BiPAP)(BiPAP)• BiPAP is a noninvasive form of BiPAP is a noninvasive form of

mechanical ventilation mechanical ventilation provided by provided by means of a nasal mask or nasal prongs, means of a nasal mask or nasal prongs, or a full-face mask.or a full-face mask.

• The system allows the clinician to select The system allows the clinician to select two levels of positive-pressure supporttwo levels of positive-pressure support::

• An inspiratory pressure support level An inspiratory pressure support level (referred to as IPAP) (referred to as IPAP)

• An expiratory pressure called EPAP An expiratory pressure called EPAP (PEEP/CPAP level). (PEEP/CPAP level).

Common Ventilator Common Ventilator SettingsSettings parameters/ controls parameters/ controls• Fraction of inspired oxygen (FIOFraction of inspired oxygen (FIO2))• Tidal Volume (VT)Tidal Volume (VT)• Peak Flow/ Flow RatePeak Flow/ Flow Rate• Respiratory Rate/ Breath Rate / Respiratory Rate/ Breath Rate /

Frequency ( F)Frequency ( F)• Minute Volume (VE)Minute Volume (VE)• I:E Ratio (Inspiration to I:E Ratio (Inspiration to

Expiration Ratio)Expiration Ratio)• SighSigh

● ●Fraction of inspired Fraction of inspired oxygen (FIOoxygen (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 FIO2 are

based on ABGs and the SaO2.

• In adult patients the initial FiO2 may 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 FIO2 is adjusted to maintain an SaO2 of greater than 90% (roughly equivalent to a PaO2 >60 mm Hg).

• Oxygen toxicity is a concern when an FIO2 of greater than 60% is required for more than 25 hours

Signs and symptoms of oxygen Signs and symptoms of oxygen toxicity :-toxicity :-

1-1- Flushed face Flushed face

2- 2- Dry coughDry cough

3-3- Dyspnea Dyspnea

4-4- Chest pain Chest pain

5-5- Tightness of chest Tightness of chest

6-6- Sore throat Sore throat

● ●Tidal Volume (VT)Tidal Volume (VT)• The volume of air delivered to a The volume of air delivered to a

patient during a ventilator breath. patient during a ventilator breath.

• The amount of air inspired and The amount of air inspired and expired with each breath. expired with each breath.

• Usual volume selected is between Usual volume selected is between 5 5 to 15 ml/ kg body weight)to 15 ml/ kg body weight)

• In the volume ventilator, Tidal In the volume ventilator, Tidal volumes of 10 to 15 mL/kg of body volumes of 10 to 15 mL/kg of body weight were traditionally used. weight were traditionally used.

• the large tidal volumes may lead to the large tidal volumes may lead to (volutrauma)(volutrauma) aggravate the damage aggravate the damage inflicted on the lungsinflicted on the lungs

• For this reason, lower tidal volume For this reason, lower tidal volume targets (6 to 8 mL/kg) are now targets (6 to 8 mL/kg) are now recommended.recommended.

● ●Peak Flow/ Flow RatePeak Flow/ Flow Rate• The speed of delivering air per unit The speed of delivering air per unit

of time, and is expressed in liters of time, and is expressed in liters per minute. per minute.

• The higher the flow rate, the faster The higher the flow rate, the faster peak airway pressure is reached peak airway pressure is reached and the shorter the inspiration;and the shorter the inspiration;

• The lower the flow rate, the longer The lower the flow rate, the longer

the inspiration.the inspiration.

● ●Respiratory Rate/ BreathRespiratory Rate/ Breath Rate / Frequency ( F)Rate / Frequency ( F)

• The number of breaths the ventilator The number of breaths the ventilator will deliver/minute will deliver/minute (10-16 b/m). (10-16 b/m).

• Total respiratory rate equals Total respiratory rate equals patient patient rate plus ventilator rate.rate plus ventilator rate.

• The nurse double-checks the The nurse double-checks the functioning of the ventilator by functioning of the ventilator by observing the patientobserving the patient’’s respiratory s respiratory rate.rate.

For adult patients and older For adult patients and older children:- children:-

With COPDWith COPD

• A reduced tidal volume A reduced tidal volume

• A reduced respiratory rateA reduced respiratory rate

For infants and younger children:-For infants and younger children:-

• A small tidal volumeA small tidal volume

• Higher respiratory rateHigher respiratory rate

● ●Minute Volume (VE)Minute Volume (VE)

• The volume of expired air in one The volume of expired air in one minute .minute .

• Respiratory rate times tidal Respiratory rate times tidal volume equals minute ventilation volume equals minute ventilation

VE = VE = (VT x F)(VT x F)

• In special cases, hypoventilation In special cases, hypoventilation

or hyperventilation is desired or hyperventilation is desired

In a patient with head injuryIn a patient with head injury, ,

• Respiratory alkalosis may be required Respiratory alkalosis may be required to promote cerebral vasoconstriction, to promote cerebral vasoconstriction, with a resultant decrease in ICP. with a resultant decrease in ICP.

• In this case, the tidal volume and In this case, the tidal volume and

respiratory rate are increased respiratory rate are increased ( hyperventilation) to achieve the ( hyperventilation) to achieve the

desired alkalotic pH by manipulating desired alkalotic pH by manipulating the PaCOthe PaCO2. .

In a patient with COPDIn a patient with COPD • Baseline ABGs reflect an elevated Baseline ABGs reflect an elevated

PaCOPaCO2 should not hyperventilated. should not hyperventilated. Instead, the goal should be Instead, the goal should be restoration of the baseline PaCOrestoration of the baseline PaCO2. .

• These patients usually have a large These patients usually have a large carbonic acid load, and lowering their carbonic acid load, and lowering their carbon dioxide levels rapidly may carbon dioxide levels rapidly may result in seizures. result in seizures.

● ●I:E Ratio (Inspiration toI:E Ratio (Inspiration to Expiration Ratio)Expiration Ratio)-:-:

• The ratio of inspiratory time to The ratio of inspiratory time to expiratory time during a breath expiratory time during a breath

(Usually (Usually = 1:2)= 1:2)

● ●SighSigh• A deep breath. A deep breath.

• A breath that has a greater volume than the A breath that has a greater volume than the tidal volume.tidal volume.

• It provides hyperinflation and prevents It provides hyperinflation and prevents atelectasis. atelectasis.

• Sigh volumeSigh volume ::------------------Usual volume is ------------------Usual volume is 1.5 1.5 ––2 times tidal volume.2 times tidal volume.

• Sigh rate/ frequency :Sigh rate/ frequency :---------Usual rate is 4 ---------Usual rate is 4 to 8 times an hour.to 8 times an hour.

● ●Peak Airway PressurePeak Airway Pressure-:-:

• In adultsIn adults if the peak airway pressure if the peak airway pressure is persistently is persistently above 45 cmHabove 45 cmH2O, the O, the risk of barotrauma is increasedrisk of barotrauma is increased and and efforts should be made to try to efforts should be made to try to reduce the peak airway pressure. reduce the peak airway pressure.

• In infants and childrenIn infants and children it is unclear it is unclear what level of peak pressure may what level of peak pressure may cause damage. cause damage. In general, keeping In general, keeping peak pressures below 30 is peak pressures below 30 is desirabledesirable. .

● ●Pressure LimitPressure Limit• On volume-cycled ventilators, the On volume-cycled ventilators, the

pressure limit dial pressure limit dial limits the highest limits the highest pressure allowed in the ventilator pressure allowed in the ventilator circuit.circuit.

• Once the high pressure limit is Once the high pressure limit is reached, inspiration is terminated.reached, inspiration is terminated.

• Therefore, if the pressure limit is Therefore, if the pressure limit is being constantly reached, being constantly reached, the the designated tidal volume is not being designated tidal volume is not being delivered to the patient. delivered to the patient.

● ●Sensitivity(Sensitivity(trigger trigger

SensitivitySensitivity))• The sensitivity function controls the The sensitivity function controls the

amount of patient effort needed to amount of patient effort needed to initiate an inspirationinitiate an inspiration

• Increasing the sensitivityIncreasing the sensitivity (requiring (requiring less negative force) less negative force) decreases the decreases the amount of workamount of work the patient must do to the patient must do to initiate a ventilator breath. initiate a ventilator breath.

• Decreasing the sensitivity increases Decreasing the sensitivity increases the amount of negative pressurethe amount of negative pressure that that the patient needs to initiate inspiration the patient needs to initiate inspiration and increases the work of breathing.and increases the work of breathing.

• The most common setting for The most common setting for pressure sensitivity are -1 to -2 cm pressure sensitivity are -1 to -2 cm HH22OO

• The more negative the number the The more negative the number the harder it to breath.harder it to breath.

Ensuring humidification and Ensuring humidification and thermoregulationthermoregulation• All air delivered by the ventilator passes All air delivered by the ventilator passes

through the water in the humidifier, where it through the water in the humidifier, where it is warmed and saturated. is warmed and saturated.

• Humidifier temperatures should be kept close Humidifier temperatures should be kept close to body temperature to body temperature 35 35 ººC- 37C- 37ººC.C.

• In some rare instances (severe hypothermia), In some rare instances (severe hypothermia), the air temperatures can be increased. the air temperatures can be increased.

• The humidifier should be The humidifier should be checked for checked for adequate water levelsadequate water levels

• An empty humidifier contributes to An empty humidifier contributes to drying the airway, often with drying the airway, often with resultant dried secretions, mucus resultant dried secretions, mucus plugging and less ability to suction plugging and less ability to suction out secretions.out secretions.

• Humidifier Humidifier should not be overfilledshould not be overfilled as as this may increase circuit resistance this may increase circuit resistance and interfere with spontaneous and interfere with spontaneous breathing.breathing.

• As air passes through the ventilator As air passes through the ventilator to the patient, to the patient, water condenses in water condenses in the corrugated tubingthe corrugated tubing. This moisture . This moisture is considered contaminatedis considered contaminated and and must must be drained into a receptacle and not be drained into a receptacle and not back into the sterile humidifier. back into the sterile humidifier.

• If the water is allowed to build up, If the water is allowed to build up, resistance is developed in the circuit resistance is developed in the circuit and PEEP is generated. In addition, if and PEEP is generated. In addition, if moisture accumulates near the moisture accumulates near the endotracheal tube, the patient can endotracheal tube, the patient can aspirate the water. aspirate the water.

• The nurse and respiratory therapist The nurse and respiratory therapist jointly are responsible for preventing jointly are responsible for preventing this condensation buildup. The this condensation buildup. The humidifier is an ideal medium for humidifier is an ideal medium for bacterial growth. bacterial growth.

Ventilator alarmsVentilator alarms-:-:• Mechanical ventilators comprise Mechanical ventilators comprise

audible and visual alarm systemsaudible and visual alarm systems, , which act as immediate warning which act as immediate warning signals to altered ventilation. signals to altered ventilation.

• Alarm systems can be categorized Alarm systems can be categorized according to volume and pressure according to volume and pressure (high and low). (high and low).

• High-pressure alarms warn of rising High-pressure alarms warn of rising pressures. pressures.

• Low-pressure alarms warn of Low-pressure alarms warn of disconnection of the patient from the disconnection of the patient from the ventilator or circuit leaks. ventilator or circuit leaks.

Complications Complications of Mechanical Ventilation:-of Mechanical Ventilation:-

I- I- Airway Complications,Airway Complications,

II-II- Mechanical complications, Mechanical complications,

III-III- Physiological Complications, Physiological Complications,

IV-IV- Artificial Airway Complications. Artificial Airway Complications.

I- Airway ComplicationsI- Airway Complications

1-1- Aspiration Aspiration

2- 2- Decreased clearance of Decreased clearance of secretionssecretions

3-3- Nosocomial or ventilator- Nosocomial or ventilator-acquiredacquired

pneumoniapneumonia

II- Mechanical II- Mechanical complicationscomplications1-1- Hypoventilation with atelectasis with Hypoventilation with atelectasis with

respiratoryrespiratory acidosis or hypoxemia.acidosis or hypoxemia.2- 2- Hyperventilation with hypocapnia and Hyperventilation with hypocapnia and

respiratory alkalosisrespiratory alkalosis3- 3- Barotrauma Barotrauma a- Closed pneumothorax, a- Closed pneumothorax, b- Tension pneumothorax, b- Tension pneumothorax, c- Pneumomediastinum, c- Pneumomediastinum, d- Subcutaneous emphysema.d- Subcutaneous emphysema.4-4- Alarm Alarm ““turned offturned off””5- 5- Failure of alarms or ventilatorFailure of alarms or ventilator6- 6- Inadequate nebulization or humidificationInadequate nebulization or humidification7-7- Overheated inspired air, resulting in Overheated inspired air, resulting in

hyperthermiahyperthermia

III- Physiological III- Physiological ComplicationsComplications1-1- Fluid overload with humidified air Fluid overload with humidified air

andand sodium chloride (NaCl) retentionsodium chloride (NaCl) retention2-2- Depressed cardiac function and Depressed cardiac function and hypotensionhypotension3- 3- Stress ulcersStress ulcers4- 4- Paralytic ileusParalytic ileus5-5- Gastric distension Gastric distension6-6- Starvation Starvation7-7- Dyssynchronous breathing pattern Dyssynchronous breathing pattern

IV- Artificial Airway ComplicationsIV- Artificial Airway ComplicationsA- Complications related toA- Complications related to Endotracheal TubeEndotracheal Tube-:-:

1-1- Tube kinked or plugged Tube kinked or plugged

2-2- Rupture of piriform sinus Rupture of piriform sinus

3-3- Tracheal stenosis or tracheomalacia Tracheal stenosis or tracheomalacia

4-4- Mainstem intubation with contralateral Mainstem intubation with contralateral ((located on or affecting the opposite side of thelocated on or affecting the opposite side of the

•lunglung) lung atelectasis) lung atelectasis

5-5- Cuff failure Cuff failure

6-6- Sinusitis Sinusitis

7- 7- Otitis mediaOtitis media

8-8- Laryngeal edema Laryngeal edema

B- Complications related toB- Complications related to Tracheostomy tube Tracheostomy tube-:-:

1-1- Acute hemorrhage at the site Acute hemorrhage at the site2-2- Air embolism Air embolism3-3- Aspiration Aspiration4- 4- Tracheal stenosisTracheal stenosis5-5- Erosion into the innominate artery with Erosion into the innominate artery with

exsanguinationexsanguination6- 6- Failure of the tracheostomy cuffFailure of the tracheostomy cuff7-7- Laryngeal nerve damage Laryngeal nerve damage8-8- Obstruction of tracheostomy tube Obstruction of tracheostomy tube9- 9- PneumothoraxPneumothorax10- 10- Subcutaneous and mediastinal emphysemaSubcutaneous and mediastinal emphysema11- 11- Swallowing dysfunctionSwallowing dysfunction12-12- Tracheoesophageal fistula Tracheoesophageal fistula13- 13- InfectionInfection14-14- Accidental decannulation with loss of airway Accidental decannulation with loss of airway

Nursing care of patients on Nursing care of patients on mechanical ventilationmechanical ventilation

Assessment:Assessment:

1-1- Assess the patient Assess the patient

2-2- Assess the artificial airway Assess the artificial airway (tracheostomy(tracheostomy

or endotracheal tube)or endotracheal tube)

3-3- Assess the ventilator Assess the ventilator

Nursing InterventionsNursing Interventions1-1-Maintain airway patency & Maintain airway patency &

oxygenationoxygenation2-2- Promote comfort Promote comfort3-3- Maintain fluid & electrolytes Maintain fluid & electrolytes

balancebalance4- 4- Maintain nutritional stateMaintain nutritional state5- 5- Maintain urinary & bowel Maintain urinary & bowel

eliminationelimination6-6- Maintain eye , mouth and Maintain eye , mouth and

cleanliness and integrity:-cleanliness and integrity:-7-7- Maintain mobility/ Maintain mobility/

musculoskeletal function:-musculoskeletal function:-

Nursing InterventionsNursing Interventions8-8- Maintain safety:- Maintain safety:-9- 9- Provide psychological supportProvide psychological support10-10- Facilitate communication Facilitate communication11- 11- Provide psychological support Provide psychological support

& information to family & information to family 12- 12- Responding to ventilator Responding to ventilator

alarms /Troublshootingalarms /Troublshooting ventilator alarmsventilator alarms13- 13- Prevent nosocomial infectionPrevent nosocomial infection14- 14- DocumentationDocumentation

Responding To AlarmsResponding To Alarms• If an alarm sounds, respond immediately If an alarm sounds, respond immediately

because the problem could be serious. because the problem could be serious.

• Assess the patient firstAssess the patient first, while you , while you silence silence the alarm.the alarm.

• If you can not quickly identify the problem, If you can not quickly identify the problem, take the patient off the ventilator and take the patient off the ventilator and ventilate him with a resuscitation bag ventilate him with a resuscitation bag connected to oxygen source until the connected to oxygen source until the physician arrives.physician arrives.

• A nurse or respiratory therapist must A nurse or respiratory therapist must respond to every ventilator alarm.respond to every ventilator alarm.

•Alarms must never be Alarms must never be ignored or disarmed.ignored or disarmed.

•Ventilator malfunction is a Ventilator malfunction is a

potentially serious problem.potentially serious problem. Nursing or respiratory Nursing or respiratory therapists perform ventilator therapists perform ventilator checks every 2 to 4 hours, checks every 2 to 4 hours, and recurrent alarms may and recurrent alarms may alert the clinician to the alert the clinician to the possibility of an equipment-possibility of an equipment-related issue. related issue.

•When device malfunction is When device malfunction is suspected, a second person suspected, a second person manually ventilates the manually ventilates the patientpatient while the nurse or while the nurse or therapist looks for the cause. therapist looks for the cause.

•If a problem cannot be If a problem cannot be promptly corrected by promptly corrected by ventilator adjustment, ventilator adjustment, a a different machinedifferent machine is procured is procured so the ventilator in question so the ventilator in question can be taken out of service for can be taken out of service for analysis and repair by analysis and repair by technical staff.technical staff.

Causes of Ventilator Causes of Ventilator AlarmsAlarms

High pressure alarmHigh pressure alarm

• Increased secretionsIncreased secretions• Kinked ventilator tubing or Kinked ventilator tubing or

endotracheal tube (ETT)endotracheal tube (ETT)• Patient biting the ETTPatient biting the ETT• Water in the ventilator tubing.Water in the ventilator tubing.• ETT advanced into right ETT advanced into right

mainstem bronchus.mainstem bronchus.

Low pressure alarmLow pressure alarm

• Disconnected tubingDisconnected tubing

• A cuff leakA cuff leak

• A hole in the tubing A hole in the tubing (ETT or (ETT or ventilator tubing)ventilator tubing)

• A leak in the humidifierA leak in the humidifier

Oxygen alarmOxygen alarm

• The oxygen supply is insufficient or is The oxygen supply is insufficient or is not properly connected.not properly connected.

High respiratory rate alarmHigh respiratory rate alarm

•Episodes of tachypnea,

•Anxiety,

•Pain,

•Hypoxia,

•Fever.

-

Apnea alarmApnea alarm

• During weaning, indicates that During weaning, indicates that the patient has a slow the patient has a slow Respiratory rate and a period of Respiratory rate and a period of apnea. apnea.

Temperature alarmTemperature alarm

• Overheating due to too low or Overheating due to too low or no gas flow.no gas flow.

• Improper water levelsImproper water levels

•

Methods of WeaningMethods of Weaning

1-1- T-piece trial, T-piece trial,

2-2- Continuous Positive Airway Pressure Continuous Positive Airway Pressure (CPAP) weaning,(CPAP) weaning,

3-3- Synchronized Intermittent Mandatory Synchronized Intermittent Mandatory Ventilation (SIMV) weaning,Ventilation (SIMV) weaning,

4-4- Pressure Support Ventilation (PSV) Pressure Support Ventilation (PSV) weaning.weaning.

11 - -T-Piece trialT-Piece trial

• It consists of It consists of removing the patient removing the patient from the ventilator and having him / from the ventilator and having him / her breathe spontaneously on a T-her breathe spontaneously on a T-tube connected to oxygen source. tube connected to oxygen source.

• During T-piece weaning, periods of During T-piece weaning, periods of ventilator support are alternated with ventilator support are alternated with spontaneous breathing.spontaneous breathing.

• The goal is The goal is to progressively increase to progressively increase the time spent off the ventilator.the time spent off the ventilator.

22--Synchronized Intermittent Synchronized Intermittent Mandatory Ventilation ( SIMV) Mandatory Ventilation ( SIMV) WeaningWeaning

• SIMV is the most common method of SIMV is the most common method of weaning. weaning.

• It consists of It consists of gradually decreasing gradually decreasing the number of breaths delivered by the number of breaths delivered by the ventilatorthe ventilator to allow the patient to to allow the patient to increase number of spontaneous increase number of spontaneous breathsbreaths

33--Continuous Positive Airway Continuous Positive Airway Pressure ( CPAP) WeaningPressure ( CPAP) Weaning

• When placed on CPAP, When placed on CPAP, the patient does the patient does all the work of breathing without the all the work of breathing without the aid of a back up rate or tidal volume.aid of a back up rate or tidal volume.

• No mandatory (ventilator-initiated) No mandatory (ventilator-initiated) breaths are delivered in this mode i.e. breaths are delivered in this mode i.e. all ventilation is spontaneously all ventilation is spontaneously initiated by the patient.initiated by the patient.

• Weaning by gradual decrease in Weaning by gradual decrease in pressure valuepressure value

44 - -Pressure Support Ventilation Pressure Support Ventilation (PSV) Weaning(PSV) Weaning• The patient must initiate all pressure The patient must initiate all pressure

support breaths. support breaths. • During weaning using the PSV mode During weaning using the PSV mode the the

level of pressure support is gradually level of pressure support is gradually decreaseddecreased based on the patient maintaining based on the patient maintaining an adequate tidal volume (8 to 12 mL/kg) an adequate tidal volume (8 to 12 mL/kg) and a respiratory rate of less than 25 and a respiratory rate of less than 25 breaths/minute. breaths/minute.

• PSV weaning is indicated for :-PSV weaning is indicated for :-

- - Difficult to wean Difficult to wean patientspatients - - Small spontaneous tidal volume.Small spontaneous tidal volume.

Weaning readiness CriteriaWeaning readiness Criteria • Awake and alertAwake and alert

• Hemodynamically stable, adequately Hemodynamically stable, adequately resuscitated, and not requiring resuscitated, and not requiring vasoactive supportvasoactive support

• Arterial blood gases (ABGs) normalized Arterial blood gases (ABGs) normalized or at patientor at patient’’s baselines baseline

- PaCO- PaCO2 acceptable acceptable - PH of 7.35 - PH of 7.35 –– 7.45 7.45 - PaO- PaO2 > 60 mm Hg > 60 mm Hg

, , - SaO- SaO2 >92% >92% - FIO- FIO2 ≤40% ≤40%

• Positive end-expiratory pressure Positive end-expiratory pressure (PEEP) ≤5 cm H(PEEP) ≤5 cm H2OO

• F < 25 / minuteF < 25 / minute

• Vt 5 ml / kg Vt 5 ml / kg

• VE 5- 10 L/m (f x Vt)VE 5- 10 L/m (f x Vt)

• VC > 10- 15 ml / kg VC > 10- 15 ml / kg

• PEP (positive expiratory PEP (positive expiratory pressure) > - 20 cm H2O pressure) > - 20 cm H2O ( indicates patient( indicates patient’’s ability to s ability to take a deep breath & cough),take a deep breath & cough),

• Chest x-ray reviewed for correctable Chest x-ray reviewed for correctable factors; treated as indicated,factors; treated as indicated,

• Major electrolytes within normal Major electrolytes within normal range,range,

• Hematocrit >25%,Hematocrit >25%,• Core temperature >36°C and <39°C,Core temperature >36°C and <39°C,• Adequate management of Adequate management of

pain/anxiety/agitation,pain/anxiety/agitation,• Adequate analgesia/ sedation Adequate analgesia/ sedation

(record scores on flow sheet),(record scores on flow sheet),• No residual neuromuscular No residual neuromuscular

blockade.blockade.

Role of nurse before Role of nurse before weaningweaning-:-:

1- Ensure that indications for the 1- Ensure that indications for the implementation of Mechanical ventilation implementation of Mechanical ventilation have improvedhave improved

2- Ensure that all factors that may interfere 2- Ensure that all factors that may interfere with successful weaning are corrected:-with successful weaning are corrected:-

- Acid-base abnormalitie - Acid-base abnormalitie - Fluid imbalance- Fluid imbalance - Electrolyte abnormalities- Electrolyte abnormalities - Infection- Infection

- Fever- Fever - Anemia - Anemia - Hyperglycemia- Hyperglycemia - Protein - Protein - Sleep deprivation- Sleep deprivation

Role of nurse before Role of nurse before weaningweaning-:-:

3- Assess readiness for weaning 3- Assess readiness for weaning 4- Ensure that the weaning criteria / 4- Ensure that the weaning criteria /

parameters are met.parameters are met.5- Explain the process of weaning to the 5- Explain the process of weaning to the

patient and offer reassurance to the patient and offer reassurance to the patient.patient.

6- Initiate weaning in the morning 6- Initiate weaning in the morning when the patient is rested.when the patient is rested.

7- Elevate the head of the bed & 7- Elevate the head of the bed & Place the patient uprightPlace the patient upright

8- Ensure a patent airway and 8- Ensure a patent airway and suction if necessary before a suction if necessary before a weaning trial,weaning trial,

9- Provide for rest period on 9- Provide for rest period on ventilator for 15 ventilator for 15 –– 20 minutes after 20 minutes after suctioning.suctioning.

10- Ensure patient10- Ensure patient’’s comfort & administer s comfort & administer pharmacological agents for comfort, such pharmacological agents for comfort, such

asas bronchodilators or sedatives as indicated.bronchodilators or sedatives as indicated. 11- Help the patient through some of the 11- Help the patient through some of the discomfort and apprehension. discomfort and apprehension.

12- Support and reassurance help the patient12- Support and reassurance help the patient through the discomfort and apprehension through the discomfort and apprehension as remains with the patient after initiationas remains with the patient after initiation of the weaning process. of the weaning process.

13- Evaluate and document the patient13- Evaluate and document the patient’’s s response to weaning.response to weaning.

Role of nurse during Role of nurse during weaningweaning-:-:

1-1- Wean only during the day. Wean only during the day.2-2- Remain with the patient during Remain with the patient during initiation of weaning.initiation of weaning.3-3- Instruct the patient to relax and breathe Instruct the patient to relax and breathe normally.normally.4-4- Monitor the respiratory rate, vital signs, Monitor the respiratory rate, vital signs, ABGs, diaphoresis and use of accessory ABGs, diaphoresis and use of accessory muscles frequently.muscles frequently.

If signs of fatigue or respiratory distress If signs of fatigue or respiratory distress develop. develop.

• Discontinue weaning trials.Discontinue weaning trials.

Signs of Weaning Intolerance Signs of Weaning Intolerance CriteriaCriteria• 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

• 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

Role of nurse after Role of nurse after weaningweaning

1- Ensure that extubation criteria 1- Ensure that extubation criteria areare

met .met .

2- Decanulate or extubat2- Decanulate or extubat

2- Documentation 2- Documentation

Good Good LuckLuck