03 Ventilation

Medical Training- Ventilation Options -

For internal use only

© WEINMANN GERÄTE FÜR MEDIZIN GMBH+CO.KG, Author: S. El Diwany MEDUMAT Transport Product Presentation, June 2008 2

Objective of Presentation

• This presentation on ventilation gives the reader an overview of the available pressure and volume-controlled types of ventilation..

• The conventional processes, including setting options on the ventilators, are explained.

• The reader will also learn about the use of Non Invasive Ventilation (NIV) with MEDUMAT Transport.


Contents

• Functions and Physiological Goals of Ventilation• Ventilation Basics• Terminology• Assisted Ventilation Modes• Controlled Ventilation Modes

– Volume-controlled Ventilation

– Pressure-controlled Ventilation

• Non-Invasive Ventilation (NIV)


Oxygen or Ventilation ?


Ventilation Functions

• Influence gas exchange• Take over the work of respiration• The type of ventilation describes the changing relationship between patient and ventilator:

– Controlled: The device takes over the work of breathing.

– Augmented/ assisted/ supported: The work of breathing is shared by the device and patient.

– Spontaneous: The patient takes on the work of breathing.


Physiological Goals of Ventilation

• Alveolar ventilation• Arterial oxygenation• Increase of end-inspiratory and end-expiratory lung volume• Unloading respiratory musculature


Clinical Goals of Ventilation

• Treatment of hypoxemia• Treatment of respiratory acidosis • Treatment of dyspnea• Prevention/treatment of atelectasis• Treatment of respiratory muscle fatigue• Allow analgesic sedation and muscle relaxation• Reduction of systemic and/or myocardial oxygen need• Reduction of intracranial pressure• Stabilization of thoracic wall


VS CPAP

CPAP/ ASB CPPV

PSV SVV SPVNIV VC PC PCV

ASB BIPAP IPPV SIMV

BiLevel/ ASB PLV

PEEP


Spontaneous Breathing• Inspiration: Negative pressure• Expiration: Positive pressure


Ventilation - Terminology


Spontaneous Breathing vs. Ventilation

• Spontaneous breathing: Passive volume expansion of lungs effected by pulling of rib musculature and diaphragm

• Ventilation: Active volume expansion by introducing volume or ventilation pressure.


Ventilation Systems

•Terminology

•Assisted ventilation

•Controlled ventilation

•Volume-controlled

•Pressure-controlled

•Combinations


PEEP• Definition:

– Positive End Expiratory Pressure

– In controlled ventilation PEEP corresponds to CPAP of spontaneous breathing

– Advantages:• Decline in atelectasis• Higher volume per unit of pressure increase (predilation)

– Disadvantages:• Increase of maximum ventilation pressure• Impairment of venous blood backflow

• Application:– With every type of ventilation at least PEEP 5


Assisted Ventilation Modes

• CPAP mode increases respiratory pressure level to raise the Functional Residual Capacity (FRC).

• This mode is used only on patients with sufficient spontaneous breathing.

• Assisted Spontaneous Breathing (ASB) mode provides pressure support in cases of insufficient spontaneous breathing. The patient can breathe spontaneously without restriction, but gets support for his respiratory work from MEDUMAT Transport.


Supporting Mode (CPAP)• Continuous Positive Airway Pressure (CPAP)

• Supports the respiratory work of the patient• Respiratory rate, pattern and tidal volume are determined by patient• Respiratory work is made easier.


Assisted Spontaneous Breathing (ASB)

• Assisted spontaneous breathing• Pressure support of every breath of patient• Patient has to “trigger” the device• Can combine CPAP, BIPAP, SIMV

• Spontaneous breathing• CPAP / PEEP 10 cm

H2O• ASB 7 cm H2O


Controlled Ventilation

• Takes over all respiratory work of patient

• Determines tidal volume by ventilation modes of – pressure-controlled

– volume controlled

• Assisted modes (ASB/CPAP) can be combined


Volume vs. Pressure-controlled Ventilation

• Volume-controlled modes ensure tidal and Respiratory Minute Volume (RMV) with adherence to an upper pressure limit.

• Pressure-controlled modes maintain maximum ventilator pressures and have a more physiological character. There is no volume guarantee, which makes monitoring of tidal volume and RMV necessary.

• Supporting modes combine the advantages of both systems.


Volume-controlled Ventilation

• The inspiratory gas flow is maintained until a certain volume is reached. • Airway pressure is passive (danger of barotrauma).• Combination with pressure limit makes sense.• Initially areas with high compliance and low resistance are ventilated and

then plateau pressure is reached.



Settings: Respiratory Minute Volume (rate x tidal volume)Limit or control dimension: maximum airway pressure

Advantage: • Tidal volume is maintained

even when pulmonary mechanics change.

Disadvantage: • Danger of pressure-caused

damage to lungs when pulmonary mechanics deteriorate


Abbreviations in Volume-controlled Ventilation

IPPV: Intermittent Positive Pressure VentilationPLV: Pressure Limited VentilationCPPV: Continuous Positive Pressure Ventilation

(with set PEEP level)VC: Volume ControlSVV: Smart Volume Ventilation



• IPPV/CPPV– Intermittent Positive Pressure Ventilation– With PEEP = CPPV : Continuous Positive Pressure Ventilation– Corresponds to completely controlled ventilation– Time-controlled, constant volume, limited pressure


IPPV Settings

• Respiratory rate: Choice between 10 to 20 /minute• Tidal volume: 6 to 10 ml kg KG• I:E ratio: 1:1 or 1:1,7• Oxygen concentration: FiO2 0,3 – 1,0• Pressure limit: pMax 30 cm H2O• PEEP: 5 cm H2O• Inspiration segmentation (plateau)


Special Emergency Mode

• IPPV ventilation• Pre-set for

– Baby (10 kg)– Child (20 kg)– Adult (75 kg)


Special Emergency Mode


SIMV

• Synchronized Intermittent Mandatory Ventilation

• Patient is given a pre-set minimum number of breaths with a defined volume (see IPPV)• Combination of controlled ventilation, synchronized mechanical breaths triggered by the

patient, and spontaneous breathing• The patient may breathe independently (see CPAP-ASB) and direct the device. • Synchronized mechanical breaths are possible only within an “anticipated breath

window”.


SIMV Settings• Settings for IPPV/CPPV breaths

– Tidal volume 6 to 10ml kgKG– Respiratory rate: 4 to 10– I:E 1:1 – 1.7

• PEEP/CPAP 5 cm H2O• Setting for SIMV

– Trigger threshold (l/min) of patient 3 l/min

• Oxygen concentration: FiO2 0.3 – 1,0

• Pressure limit: pMax 30 cm H2O


SVV

• Smart Volume Ventilation• Weinmann‘s special mode of volume-controlled ventilation• All pressure-controlled ventilation modes can be set


Pressure-controlled Ventilation• Application of gas flow until a pre-set airway pressure is reached. • The pressure is maintained for a certain amount of time and then reduced again during expiration. • Tidal volume results from the ventilation pressure and the mechanical characteristics of the lungs. • Tidal volume and gas flow are dependent on the mechanical characteristics of the lungs. • Initially high and then decreased flow = decelerated flow


Pressure-controlled Ventilation

Settings:Airway pressure, respiratory rateLimit or control dimension: Tidal or respiratory minute volume

Advantage: • The optimum pressure range

can be set individually for each lung. The lung is protected and ventilator-induced lung damage can be avoided.

Disadvantage: • When respiratory mechanics

deteriorate, tidal volume decreases and with it the ventilation.

• Tidal volume has to be measured at end-expiratory point when pressure-controlled or non-volume constant ventilation is used.


Abbreviations in Pressure-controlled Ventilation Modes

PCV: Pressure Control Ventilationallows no spontaneous breathing by patient.

BIPAP: Biphasic Positive Airway Pressure ® BiLevel:Combination of timed change of two pressure levelsSPV: Smart Pressure Ventilation

Weinmann-specific platform for set up of pressure-controlled ventilation mode.


SPV

• Smart Pressure Ventilation• Weinmann’s special mode of pressure-controlled ventilation• All pressure-controlled ventilation modes can be set up• CPAP/ASB can be used only at the lower pressure level


Bi-level Ventilation

• Biphasic Positive Airway Pressure= ventilation with two pressure levels (also known as BI-level Positive Airway Pressure)

• Pressure and time-controlled ventilation mode• Volume is not constant !• State-of-the-art ventilation mode in Intensive Care Unit (ICU)


Bi-level

• Mode of Operation:

– Combination of CPAP and pressure-controlled ventilation

– Two (2) different pressure levels

– Spontaneous breathing at both levels is allowed at any time during ventilation

– ASB support is possible


Bi-Level: Settings

• Rate calculation:

– 60 sec. / targeted rate

– e.g., 10 rate = 6-second respiratory cycle

• Respiratory cycle:

– Set I:E via time selection

– e.g.: T1(Inspiration) 2 seconds / T2 (Expiration) 4 seconds

• Pressure level

– P1(high pressure/ inspiration)

– P2 (CPAP/PEEP/low pressure / expiration)


Combinations and Special Modes

ASB: Assisted Spontaneous BreathingBiLevel ASB: Each breath of the patient triggers a gas flow which

leads to the set inspiratory pressure level.

CPAP: Continuous Positive Airway PressureCPAP/ ASB Spontaneous breathing mode, maintains positive

pressure in airways during the entire spontaneousbreathing cycle + assisted spontaneous breathing


Ventilation Parameters

• Rate

• Pinsp Pressure

• PEEP

• Delta ASB

• Tidal volume

• Ratio Inspiration:Expiration I:E

• Minute volume

• Ramp

• FiO2

• Pmax

•Trigger


Non-Invasive Ventilation (NIV)

• For Non invasive Ventilation the patient is given a mask which, depending on type, covers the nose and mouth or the entire face or goes on the patient‘s head like a helmet.

• Basically all the ventilation modes used in invasive ventilation (via tube or tracheostoma) can be used in non-invasive ventilation.


Advantages of NIV

• Avoidance of intubation• Airways remain intact• Reduction in ventilator-induced pneumonia• Relaxation/sedation not required:

– Ø gastrointestinal atony– Ø weaning symptom

• Patient can communicate• Increase in mobility• Intermittent treatment as needed• Maintenance of glottal closure function


Indications and Contraindications of NIV

Indications:-Neuromuscular diseases (ALS, polio)-Mechanical disorders (kyphoskoliosis, etc.)-COPD-Pulmonary edema -Pneumonia-Weaning-ARDS

Contraindications:–Coma or amentia–Severe cooperation problems–Acute life-threatening hypoxia–Cardiac arrest–Hemodynamic instability–Increased risk of aspiration

• Swallowing disorders, ileus, GI bleeding, abdominal surgery (?)

–Obstruction in upper airways–Secretion retention


NIV Operational Principle- Unloading of respiratory pump

- Increase in intrathoracic pressure

- counteracts a pathological collapse of the alveolar sector

- Reduction in development of atelectasis and ventilation disorders

- Increase to FRC

- Decline in pulmonary shunt volume

- Improvement of pulmonary oxygen transfer

- Improvement in oxygenation


XAssessment of NIV in Clinical Use

• Criteria for success– Improvement in alveolar

ventilation (PaCO2 falls)

– Improvement in pulmonary gas exchange (SaO2 rises)

– Unloading of respiratory pump– Decrease in cardiac rate– Decrease in respiratory rate– Reduces agitation, angst– Reduction in dyspnea

• Cancellation criteria– Hypercapnia during NIV

– Hypoxemia with SaO2< 85%

– Acidosis (pH < 7,2)

– Rise in respiratory rate

• Dyspnea– Loss of consciousness

– Circulatory instability

– Increasing agitation, angst


Summary

• Every existent respiratory activity of the patient should be utilized !• The device should adjust to the patient – the patient should not adjust to the device !• Pressure and volume-controlled modes offer the best selection options and adaptation to patient needs.• Ventilation setup is one task; the monitoring of respiratory parameters is the second.

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03 Ventilation