Design Fabrication and Control of AMBUlator

AMBU bag or Bag Valve Mask are often used after surgeries or operations to give mechanical ventilation to the patients. When surgeries are severe, patients often take 12-24 hours to respire on their own. These bags are manually pressed by either paramedic staff or patients' relatives which is q

Project Title

Design Fabrication and Control of AMBUlator

Project Area of Specialization

Mechatronics Engineering

Project Summary

AMBU bag or Bag Valve Mask are often used after surgeries or operations to give mechanical ventilation to the patients. When surgeries are severe, patients often take 12-24 hours to respire on their own. These bags are manually pressed by either paramedic staff or patients' relatives which is quite hectic procedure as AMBU bags are required to be pressed after a fixed time period to provide patients with continuous ventilation. And if the person fails to give the required breathing cycle it can cause the patient’s death.

            To avoid the tiring and unprecise process of pressing of AMBU bag, we aimed to automate the manual resuscitator which will be an easy, simple, and low-cost ventilation method with controlled parameters. Our main objective in this project is to develop a motorized mechanism that can press an adult AMBU bag. The control of critical ventilation parameters is important according to patient needs, such as:

•  Tidal Volume (V) = 0-450 ml
•  Respiratory Rate (RR) = 10-15 breathes/min
•  Inspiratory to Expiratory ratio (I/E ratio) = 1:2

We will provide Human Machine Interface (HMI) to Doctors and Paramedic staff for setting these critical parameters.

Project Objectives

To avoid the tiring and unprecise process of pressing the AMBU bags, we aimed to automate a manual resuscitator which will be an easy, simple, and low-cost ventilation method with controlled parameters. Our main objective in this project is to develop a motorized mechanism that can press an adult AMBU bag for providing mechanical ventilation. The control of critical ventilation parameters is important according to patient needs, such as:

•  Tidal Volume (V) = 0-450 ml
• Respiratory Rate (RR) = 10-15 breathes/min
•  Inspiratory to Expiratory ratio (I/E ratio) = 1:2

We will provide Human Machine Interface (HMI) to Doctors and Paramedic staff for setting these critical parameters.

Project Implementation Method

Project Implementation:

We have studied different research papers and articles related to this project to gain the domain knowledge and also to understand the work done in the past on AMBUlators. We have studied at least 8 research papers and all of them use different approaches to provide mechanical ventilation to the patients. Then we move toward the practical implementation of our project. We first implemented the Open Lung model of AMBUlator and it took us 4 months to complete. But testing shows that the model fails to press the AMBU bag and we have to shift towards the second model.

The second model uses rack and pinion to press the AMBU bag and convert rotational motion to linear motion. The motion is controlled by a Nema-23 stepper motor with a DM542 motor driver. There are three controllers used, Arduino Mega, UNO, and NANO. The Arduino Mega act as the master and NANO and UNO will act as a slave. The TFT LCD screen will be attached to Arduino Mega and shows the set parameters, graphs, and values provided to the patient. Arduino NANO will control the motor steps and rotation while Arduino UNO will control the sensors and limit switches. The model will be powered by WAPDA supply. The unit testing of sensors and integration testing will be performed in near future.

Benefits of the Project

Our product is a safety-critical system that involves Human Life, and will incorporate safety alarms. The alarms will indicate any choking or peak pressure, problems in either circuit or patient’s lungs, inaccurate volume delivery, and changes in respiratory rate. In case of either epidemic or pandemic like Covid 19, some people feel reluctant to admit their patients to hospitals and need their personal ventilators at home for mechanical ventilation. Our product will help them to provide ventilation and will be easy-to-use device. Also, the price will be affordable as compared to the available ventilators in hospitals.

We are looking forward to making this FYP a complete product that can be installed as a Pilot Unit in Hospitals. The death rate during surgeries and major operations can also be reduced if the mechanism can be made up to the ISO Standards of Health and Safety. If we can save the life of a single patient, it will be a huge honor for us.

Technical Details of Final Deliverable

Till now we have made two prototypes for our project. First prototype failed to press the AMBU bag to give the required output. We changed the mechanism to the second prototype and used linear motion to push the AMBU Bag and the mechanism successfully pressed the BVM.

We have controlled the direction and speed of the Stepper Motor to produce the breathing mechanism (12 breaths per minute) and integrated a pressure sensor (MPX5010GP) to measure the pressure in the lungs. We are trying to achieve the specific Pressure profile. On the basis of results from the motor and sensor, we are updating the revisions of the model. We have successfully achieved breaths per minute and I: E ratio by controlling the motor movement. Also integrated flow sensors to measure the volume of the air delivered. 

In the future, we will work on the measurement of Tidal Volume delivered to the lungs, feedback system from the patient, and sense respiration through muscle movement of lungs and diaphragm. We will improve the Interface of the Mechanism and will work on the Packaging of our product.

Final Deliverable of the Project

Hardware System

Core Industry

Medical

Other Industries

Manufacturing

Core Technology

Robotics

Other Technologies

3D/4D Printing

Sustainable Development Goals

Good Health and Well-Being for People

Required Resources

If you need this project, please contact me on contact@adikhanofficial.com