introduction and defination project manegement

1. MECHANICAL VENTILATION
Introduction
(Practical aspect only)
Selam Tebeje (MD)
Anesthesiologist

2. • Definition
-any means in which devices or machines are
used to either assist or replace spontaneous
ventilation
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3. Indications for ventilation
• -inadequate ventilation
-inadequate oxygenation/intrinsic
-combination
-Cardiac insufficiency
Neurologic dysfunction
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4. Goals of ventilation
Reasonable:
-high PaO2
-Low PaCO2
Solve ventilatory problems.
Solve oxygenation problems
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5. Ventilator setting
• Nomenclatures and modes
-mode-pattern of ventilation are described by different
variable.
-variables
-Trigger
-control variable
-cycling variable
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6. Ventilator setting
• Trigger variable:
-how ventilator determines when to initiate a machine driven breath.
-time triggered
-for patients with no spontaneous ventilation.
-pressure triggered
-for patients with spontaneous ventilation.
-flow triggered
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7. Ventilator setting
Control variable:
-defines what aspect of inspiration is the primary variable controlled by
the ventilator
• pressure-fixed amount of airway pressure
• Volume controlled -volume is controlled and change in airway
resistance and lung and chest wall compliance will
result in change airway pressure.
(fixed amount of tidal volume no matter what)
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8. Ventilator setting
• Nomenclatures and modes:
• Types of breaths
Mandatory breath -source of trigger- ventilator
-time triggered
-level of support-full
Assisted breath -triggerd by patient (flow/pressure trigger)
-full/partial support
Spontaneous breath-not triggered no support
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9. Ventilator setting
• 5.common ventilator modes
1.A/C
2.SIMV
3.PCV
4.PSV
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10. Ventilator setting
• 1.A/C Mode :
-breaths –mandatory + assisted breaths-all once triggered are treated the
same ,with consistent TV
-trigger-time/pressure/flow
-control-flow/volume/pressure
-cycling -time
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11. Ventilator setting
• 1.A/C Mode
-advantages –guarantee a minimum MV
-low work of breathing
-Dis advantages -hyperventilation
-respiratory alkalosis
-auto PEEP
-low BP
-Indications –critically ill patients requiring full ventilatory support in whom
fluctuation in TV is undesirable
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12. Ventilator setting
• 2.SIMV Mode :
-+/- pressure support/assist.
-breaths -mandatory(synchronized) +assisted breaths .
-synchronized breaths
–trigger-pressure/flow
-control-flow/volume
-cycling-time
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13. Ventilator setting
• 2.SIMV Mode :
-advantages –guarantees minimum MV
-lower mean airway pressure than AC
-can provide a wide range respiratory support
-indications
–critically ill patients who are- hyperventilating
-prone to auto PEEP
-prone to high airway pressure
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14. Major difference between
AC
• RR in excess of mandatory breaths
will receive full support
• In patients with no spontaneous
breath AC=SIMV
SIMV
• RR in excess of mandatory breath
receive partial support/even may
not
may not receive support
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15. Ventilator setting
• 3.pressure control ventilation:
-Advantages
-prevents excessive airway pressure
-avoids regional alveolar over distension
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16. Ventilator setting
• 3.pressure control ventilation:
-dis advantages
-very uncomfortable
-requires deep sedation +/- paralysis
-unable minimum MV
-indications –patients with high risk of barotrauma
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17. Ventilator setting
• 4.pressure support ventilation:
-breaths –only spontaneous
-trigger –all by the patient –pressure /flow
-control-pressure
-cycling-flow
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18. Ventilator setting
• 4.pressure support ventilation:
-advantage –most confortable for awake conscious patient .
-disadvantages –patient must trigger each breaths .
-minimum MV can not guaranteed.
-associated with poorer quality sleep.
-does not provide full ventilatory support .
-indications –conscious patients prior to extubation.
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19. Ventilator setting
• 4.pressure support ventilation:
i.e -PSV( with PEEP)
-SIMV(with PEEP) with RR set to 0
• All are equivalent!!!!!!
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20. Ventilator setting
• parameters
-FiO2 –initially 100%
-PEEP-normal 3-5mmHg
-Respiratory rate-base on age
-Tidal volume-4-12ml/kg
-Minute ventilation-5-10L/min
-Inspiratory flow and pressure-peak <35mmHg
-I:E ratio-normal 1:2
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21. Monitoring the patient , alarm and
care
Monitoring;
-PR
-Bp
-EKG
-Pulseoximetry
-ETCO2
Ventilation: chest excursion and auscultation of breath sounds
Patency of the tube - suctioning of the endotracheal tube and oropharynx.
In put out put
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22. Indications for extubation
• General approaches
SIMV Weaning
Pressure Support Ventilation (PSV) Weaning
Spontaneous breathing trials should be acceptable
-minimal pressure support
-RSBI(RR/TV)<100
-adequate spontaneous TV>5ml
-Patent upper airway(leak test)
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23. THANK YOU
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