Mechanical Ventilator

The mechanical ventilation is one procedure that replaces the respiratory function of a person or helps you so that you can perform correctly. This artificial lung replaces or works in the act of inspiration and expiration ,favoring, thus, the arrival of oxygen to the body and the elimination of toxic substances such as CO2.

The ventilation can be invasive through an endotracheal tube (introduced from the nose or mouth) or a tracheostomy (hole in the trachea), and non-invasive, through different types of masks nasal, facial or buccal.

Total replacement: Controlled ventilation, the respirator provides all necessary work for breathing. indicated in severe respiratory failure or need for muscle relaxants. Activating the trigger and increasing the respiratory frequency is called controlled assisted ventilation

Partial substitution: The patient actively participates and performs part of the respiratory work (supportive pressure, CPAP)

Controlled Assisted Ventilation

Mode of total replacement of the ventilation in which all vents are mechanical type, and can operate as a controlled ventilation or as assisted ventilation

Can be applied with volume control (VCV, volume controlled ventilation) or pressure (PCV, pressure controlled ventilation).

The machine supplied in each ventilation the circulating volume or the inspiratory pressure presets

Controlled by volume (VCV): circulating volume, inspiratory flow, flow pattern, respiratory frequency and sensitivity.

Pressure controlled (PCV): inspiratory pressure, inspiratory time, respiratory rate and sensitivity.

Continuous Positive Pressure in the air way

This is a modality of spontaneous ventilation, in which the fan remains constant a default level of positive pressure during the whole cycle ventilator. The fan does not provide any mechanical cycle, so that it should not be considered as a true way of mechanical ventilation.

During the CPAP, the patient assumes the largest part of the work of breathing, since it generates its own inspiratory flow, its respiratory rate and its circulating volume, simulating in large measure the pattern of spontaneous ventilation

Design a prototype

To design a mechanical fan and understand its main operation is used:

a pressure sensor, solenoid valve, compressor

The function of the pressure sensor is to measure the air pressure that inspires the lungs and also to do the leak check

The main function of the air compressor is to make the simulation of the network of medical gases and exactly of oxygen

The electrovalve bidirectional allows you to make the process of inspiration and expiration of the patient in accordance with the established paramentros, since this opens and closes according to the time programmed by the user .

implemented code

Auto-test

• By means of a flat sequence structure was done initially the reading of the pressure sensor if the voltage recorded was lower than the established according to the characterization carried out previously, indicated leakage and furthermore this process generated a sensor calibratio

• The second sequence is to verify the correct use of the solenoid valve

• The third sequence is to verify the alarms that must be audible and visible

High Alarm:

sequence de 5 tones that repeats twice, pause, then repeats again

The color should be red indicating immediate attention

Activated when: There are leaks and breaths per minute of the patient are greater than 25 and less than 10

Medium Alarm

repeating sequence of 3 tones

the color should be yellow-medium, indicating prompt attention

Is activated when: the minute volume of the patient is greater than 10 L/min

Low alarm

1 tone, non repeating

the color should be yellow-low, indicating changes in the parameters of the patient

Is activated when the time of inspiration and expiration does not have the relation 1:2

Volume Controlled Mode

This mode is done by using a flat which allows the first moment to make the inspiration of the patient for this the compressor is turned on and the solenoid valve is activated generating that the pump is insufflate, for the expiration the solenoid valve is deactivated and Turn off the compressoThe time of inspiration and expiration is defined by the user as long as the relation 1:2 of I:E is considered

To calculate the tidal volume and the minute volume takes into account the parameters of the patient according to the following formula:

Ideal weight = height cm-100 ((age/10) x 0.9)

Tidal volume: Ideal weight x 6

Minute volume = volume tidal x RPM

CPAP

The continuous Positive Airway Pressure mode must permanently turn on the compressor and activate and deactivate the solenoid valve in such a way as to mantienga the pressure and the stable volume.