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
