Almost every bed in a hospital has a manual resuscitator (Ambu-Bag) nearby; made available in the event of a rapid response or code where healthcare workers maintain oxygenation by squeezing the bag. Emerging international health situation threatens a huge shortage for ventilators which may not be available in short notice. Automating ambu-bag application appears to be the simplest strategy that satisfies the need for low-cost mechanical ventilation, with the ability to be rapidly manufactured in large quantities. However, doing this safely is not trivial.
Manual ambu-bag usage is a stop gap solution till ventilator is available for use. In worst case scenario where ventilators are in short supply, continuation of ambu-bag usage takes place. The design below is to address long term usage by simple automation. There are multiple scenarios in which respiratory support could be needed: patients can be awake or asleep, sedated or sedated & paralyzed, breathing spontaneously, weaning off of a vent, etc. Furthermore, changing clinical presentations with Acute respiratory distress syndrome (ARDS) require shifting minute ventilation (tidal volume x respiratory rate) to “lung-protective” strategies, which place patients at risk for things like auto-PEEP. Some of these situations are simpler than others, with the simplest being ventilating a sedated, paralyzed patient and at a minimum, a safe emergency ventilator could be used in such a situation to free-up a conventional ventilator.
Further, any low-cost ventilator system must take great care regarding providing clinicians with the ability to closely control and monitor tidal volume, inspiratory pressure, bpm, and I/E ratio and be able to provide additional support in the form of PEEP, PIP monitoring, filtration, and adaptation to individual patient parameters.
Versatile and easily adoptable
Multiple bag design helps in optimal usage of a single system to multiple patients during extended ventilation. A cam driven mechanism provides a longer reliability and lesser calibration efforts. The system is rugged and can run without manual intervention for sufficient period till a suitable system can be arranged. Fully equipped, this machine can help in attending four patients during a critical situation. The bags can be replaced for various needs such as pediatric and neonatal with minimal effort and time.
Almost all standard ambu-bags can be readily placed without any special training. Also, standard patient valves help in reduced inventory for the institution. Easily fitting into the healthcare environ, immediate patient isolation is facilitated.
Agile installation, cleaning and sterilization
The machine can be run with a standard wall socket at the bedside at 220V AC 3 phase (can be modified to single phase during regular production) current supply is easy to assemble and disassemble with minimal time and effort. An effective procedure for cleaning and sterilization can be designed to suit local practice. Oxygen can be given as input through a single port which divides to the 4 different ports for different ambu-bags and has individual valves.
300-700ml (with variable control- 4 settings)
21%, ~40% ~60%
On and Off – measurements not done
5cm of water and 20 cm of water
18 BPM (controllable from 12-25. Based on input can be made an option)
Ventilator is an important patient support device in specialty medical institutions while treating lung and heart deceases. We have conceived, quickly manufactured and tested a Cam operated four patient ventilator (only the operating mechanism is common while air supply and volume control are independent for each patient) which will be a crucial aid for treating Covid-19 infected cases with breathing difficulty. Sudden influx of patients due to this pandemic may overload the hospital space while availability of such device itself in question at the first place. Covid-19 the current virus spread is expected to create breathing dysfunctions and hence, a respiratory device which can serve particular needs would suffice for such patients. We took the initiative on learning government's indication on shortage of this crucial equipment while facing this worldwide pandemic. A lot of willing companies including
1.Jega Precision Drives,
2. Sambros Tex,
have been part of development process and are equipped to manufacture in large scale. Companies have shown interest in producing the same and we have shared the initial design which they could produce in their Chennai facility which might solve the local need. We assume, we will be able to quickly transfer technology and send critical components like PEEP valve, pneumatic components and drives by which the rest, fabrication and assembly, can take place at a very fast pace at their locations.
This was developed with support of
1. Raunak MDes IISc
2. Sanketh PhD IISc
3. Prithveen, Orthoone
4. Dr Ashraya, Eye Foundation
5. Engineers at ATATRI
In the next few days we are looking at testing the same with presence of doctors and health workers to understand and improve the system. Also we are looking forward to get certification from hospital administration and health department shortly.