Mechanical Ventilation Flashcards
Mechanical ventilators require a power source to function, and they can be classified based on the type of input power they use: pneumatic, electric, or a combination of both (pneumatic- electric).
Input
operate solely on compressed gas, typically oxygen or air. They do not require electricity to function, which makes them particularly useful in situations where electricity is not available or during transport.
Pneumatic
operate using electrical
power from a battery or an external power supply.
Electric
These ventilators use a combination of compressed gas (pneumatic) and electrical power.
Pneumatic-Electric
- refers to the method by which the ventilator generates the force needed to deliver breaths to the patient.
- include _____, _____, and _______, each offering distinct
advantages and working principles.
- Drive Mechanism
- pistons, bellows, microprocessors
- use a motor-driven piston to generate the pressure required to deliver gas to the patient’s lungs.
- use motor-driven piston for pressure generation.
Piston Driven
use a bellows to deliver breaths. The bellows is compressed by a ______ or __________, pushing the gas into the patient’s lungs.
- Bellow-Driven
- mechanical or pneumatic force
- use advanced electronic systems to control the ventilator’s functions. The microprocessor, a small computer within the ventilator, processes input data from sensors and adjusts the ventilator’s operation accordingly.
Microprocessors- Controlled
determines how the ventilator’s operations are regulated and adjusted to meet the patient’s respiratory needs.
Control circuit
Involves physical components such as ____, ____, and ____ to control the ventilator’s operation.
- Mechanical
- cam, levels, and springs
Utilizes compressed gas to operate the
ventilator. Pressure and flow are controlled by ____ and ______ within the system.
- Pneumatic
- valves and diaphragm
Utilizes the principles of fluid dynamics to control the ventilator’s functions. This involves no moving parts, relying instead on ____ and _____ to regulate the system.
- Fluidic
- fluid jets and streams
Employs electrical components like ____, ____, and switches to control the ventilator’s functions. These circuits provide the power necessary for mechanical movement within the ventilator.
- Electric
_ motors and solenoids
Involves advanced electronic components like ______, ______, and transistors to manage and control the ventilator’s operation. These circuits provide precise control and monitoring of ventilation parameters.
- Electronic
- sensors, microprocessors
- Refer to the parameters that control the transitions between the different phases of the respiratory cycle.
- What are the 4 distinct phases ?
- Phase Variables
- Trigger, control, cycle, expiration
- change form expiration to inspiration
- determines when the
ventilator switches from expiration to
inspiration. - determines when inspiration begins
- ensures that the ventilator delivers a breath either based on ______ or _______.
- Trigger
- Px’s effort or pre determined ventilatory settings.
The ventilator initiates
inspiration based on a set respiratory rate or time interval.
- initiates breaths on a set RR.
- it is commonly used in _______.
- Time trigger
- full controlled ventilation
- The ventilator initiates
inspiration when it detects a patient’s effort, causing a slight drop in airway pressure. - initiates breath when px generates small negative effort.
- commonly used in _________ or ______.
- Pressure Trigger
- spontaneous breathing modes or assist control ventilation
- The ventilator detects a change in the flow rate in the circuit and initiates inspiration.
- commonly use in ______ and is preferred over ________ due to its ________ and _______.
- Flow Trigger
- modern ventilators
- pressure trigger
- greater sensitivity and quicker response
- This trigger initiates inspiration based on a change in volume due to patient effort.
- it is less commonly used and typically found in _____.
- Volume Trigger
- older models of ventilator
it can be adjusted to make it easier/harder for the px to initiate a breath.
Trigger sensitivity
- it can cause auto-triggering, where the ventilator deliver breaths w/o the true patient effort. (ex: ______, ____, _____.
- Too sensitive
- due to motion, leaks, circuit noise
the patient may have to work harder to trigger a breath, which may lead to discomfort and increase work of breathing.
Not sensitive enough
- controls the inspiratory phase of the ventilatory cycle, including the delivery of gas to the patient.
Limit Phase Variable
- The ventilator limits the pressure during inspiration to a preset value, maintaining constant pressure but varying volume.
- Ex: _________ - a mode where pressure is the limiting factor.
Note: Pressure limit does not terminate the breath, it simply limits how high the pressure can go during inspiration.
- Pressure limit
- Pressure controlled ventilation
- The ventilator delivers a preset tidal volume during inspiration, maintaining consistent volume but allowing pressure to vary.
- Ex: _______
- Volume limit
- volume controlled ventilation
- The ventilator limits the flow rate during inspiration, affecting how quickly the tidal volume is delivered.
- Ex: ______
- Flow limit
- volume control mode
- inspiration lasts for a set period regardless of
pressure or volume. - the ventilator limits the duration of inspiration based on a preset time.
Ex:______
- Time Limit
Pressure controlled mode
- This phase variable determines when the ventilator switches from the inspiratory phase to the expiratory phase.
- determine when the inspiration ends
- change form inspiration to expiration.
Cycle Phase Variable
- The ventilator ends the inspiratory phase after a set time has elapsed.
- Clinical use in patients requiring control over inspiratory time, such as ________, where pressure control is critical.
Ex: ______
- Time cycled ventilation
- COPD
- Pressure controlled ventilation
- The ventilator ends inspiration after a preset tidal volume has been delivered.
- Clinical use in px who require precise control over tidal volume.
- _______ are already hyperinflated due to air trapping.
Ex: ______
- Volume Cycle ventilation
- COPD
- Volume controlled ventilation
- The ventilator ends
inspiration when a preset pressure is reached. - Clinical use: this may be used in situations where it is important to avoid high pressure. ex: ARDS- lungs are already stiff and fragile high pressure will cause ______.
Ex: ______
- Pressure cycled ventilation
- VILU/Barotrauma
- Pressure controlled ventilation
- The ventilator ends inspiration when the flow rate decreases to a preset percentage of the peak inspiratory flow.
- Clinical use___
Ex: ______
- Flow cycled ventilation
- Spontaneous breathing
- older form of pressure controlled ventilation
- This phase variable represents the expiratory phase, during which the ventilator allows the patient to exhale.
- refers to phase of respiratory cycle where air is expelled in the lungs.
Expiration
- ventilator determine how the ventilator delivers breaths to the patient.
- refers to the parameter that ventilator directly controls during the inspiratory phase
Control Variable
- The ventilator delivers a preset tidal volume to the patient during each breath, regardless of the pressure required to achieve that volume.
- Ex: mode:______
- Volume control
- VC-CMV
- The ventilator delivers breaths to achieve a
preset pressure, maintaining this pressure throughout inspiration.
Ex: Mode: _______
- Pressure control
- PC-CMV
- refers to the ventilator’s ability to regulate the flow rate of gas delivered to the patient during inspiration.
Ex: Mode: _____
- Flow Control
- VC mode
- the duration of inspiration is set, and the ventilator adjusts other parameters to achieve the desired outcome within this set time.
Ex: Mode: ______
- Time control
- HFOV
