GB2533850A

GB2533850A - Rapid inflator

Info

Publication number: GB2533850A
Application number: GB1519821.1A
Authority: GB
Inventors: John Saggers Christopher
Original assignee: MJS HEALTHCARE Ltd
Current assignee: MJS HEALTHCARE Ltd
Priority date: 2014-11-10
Filing date: 2015-11-10
Publication date: 2016-07-06
Anticipated expiration: 2035-11-10
Also published as: WO2016075452A1; GB201519821D0; EP3217941A1; GB2533850B; GB201419964D0

Abstract

A pressure cuff inflation system, such as for treatment of deep vein thrombosis (DVT), comprises an airflow circuit for inflating one or more pressure cuffs using an air compressor 20 in communication with a pressurised air reservoir 24 arranged to accumulate air pressurised by the compressor 20 for rapid discharge into air pressure cuffs via a distributor 22A with solenoid valve-controlled 22 outlet ports 23. A controller 27 and a reservoir pressure switch 28 provides primary control of the reservoir air pressure and the controller and solenoid valve 25 provides secondary control of the release of pressurised air from the reservoir into the said distributor. The incorporation of an air reservoir enables fast pressure rise time in the cuffs whilst using only a small, quiet, low power compressor to maintain pressure in the reservoir.

Description

RAPID INFLATOR

This invention relates generally to pressure cuffs, more specifically, this invention relates to a rapidly inflatable pressure cuff system useful in treatment of venous disease like deep vein thrombosis (DVT), Lymphedema and venous ulcers.

DVT arises from the development of blood clots in a vein and is also known as venous thrombosis. The condition can occur in the larger veins in the body, usually in the limbs and commonly in the legs. DVT is treated through the prescription of anticoagulant medicines or Rivarixoban which prevent blood clots from forming easily, invasive inferior vena cava (IVC) filters, and other non-invasive and non-medicinal treatments.

Non-invasive and non-medicinal such treatments include exercise, raising the affected limb or pressure cuffs.

Pressure cuffs are worn around the affected area(s) and when in use they apply pressure all around the limb thereby restricting the blood vessels and increasing blood pressure in that area. This increased blood pressure is advantageous as it promotes the better movement of blood. Some inactive pressure cuffs rely on their elasticity to compress the affected area whilst other active pressure cuffs rely on fluid pressure inside the cuff and a compressor to maintain that pressure. It is to this type of active pressure cuff that this invention is focused.

A fast pressure rise time in the cuff(s) is advantageous, but this is currently achieved through the use of relatively high powered compressors.

The disadvantages of a high power compressor are that they are large, heavy, inefficient, relatively costly and loud. A patient may need to be treated with compression cuff(s) for several hours at a time. Throughout the night while the patient is asleep, a high power compressor will therefore be difficult to manoeuvre to an area with which the patient is comfortable, will use a large amount of electricity and will disturb the patient and neighbouring patients with its noise.

A low power compressor on the other hand can be smaller, lighter, more efficient and quieter, however, a low power compressor will not provide the desired and optimal fast pressure rise in the cuff(s) and will therefore be inferior and contrary to current practice when designing rapidly inflatable pressure cuff(s) of this type.

It is therefore an aim of the present invention to provide an inflatable pressure cuff system that can use a low power compressor yet provide a fast pressure rise time in the cuff or cuffs to which the compressor is coupled.

The present invention describes a system that uses a pressurised air reservoir such as an air chamber separate from the pressure cuff(s) thereby providing a battery of rapidly releasable compressed air. A small, quiet, energy efficient compressor can therefore be used in such a system to pressurise and maintain this chamber to a pre-set level of pressure.

The essential components to make a functioning system are an air compressor whose outlet is connected to a pressurised air reservoir such as an air receiving tank, which in turn has two air outlets. The first outlet is connected to a pressure switch and the second outlet is the air feed to a primary valve such as a solenoid valve. From that valve outlet a pressure cuff is connected along with a pressure transducer for monitoring the pressure. Finally there is a Control PCB which monitors and controls the air flow.

The advantages are that the system can be made smaller, lighter, more efficient and quieter than rapid cuff inflator systems currently on the market. The pressurised store of air can also be released into the cuff(s) very quickly, thus giving a good therapy.

According to the present invention there is provided a pressure cuff inflation system comprising an airflow circuit for inflating one or more pressure cuffs, said circuit comprising an air compressor in communication with a pressurised air distributor having one or more outlet ports adapted to communicate with air pressure cuff(s) when fitted to said distributor, valve means for opening and closing the port(s) to receipt of pressurised air, a pressurised air reservoir arranged to accumulate air pressurised by said compressor and to discharge that pressurised air into the said pressurised air distributor, primary control means for controlling the pressure of air that accumulates within the reservoir and secondary control means for controlling release of pressurised air from the reservoir into the said distributor.

In a non-exclusive embodiment, there is provided a cuff inflation system as above wherein the reservoir is located in the airflow circuit between the compressor and the distributor.

In another further non-exclusive embodiment, there is provided a cuff inflation system according to either of the previous embodiments wherein a further valve means is provided in the airflow circuit between the reservoir and the distributor.

In yet another further embodiment, there is provided a cuff inflation system as above in which the primary control means comprises a pressure switch linked to the compressor to activate the compressor upon the pressure in the reservoir reaching a predetermined threshold.

In yet another further non-exclusive embodiment, there is provided a cuff inflation system as above wherein the compressor is linked to a controller that activates said secondary control means.

In a further embodiment relating to some or all of the features above, there is provided a cuff inflation system wherein the reservoir pressure switch is linked to said controller and/or to said secondary control means.

In order that the invention may be illustrated, more rapidly appreciated, and readily carried into effect by those skilled in the art, embodiments of the invention will now be described purely by way of non-limiting example only with reference to the accompanying drawings in which: Figure 1 is a simplified schematic of the layout of a pressure cuff system according to the prior art; and Figure 2 is a simplified schematic of the layout of a pressure cuff system according to the present invention.

Figure 1 demonstrates an already known and used therapeutic pressure cuff inflation system (1) comprising a relatively high power compressor (10), an air supply hose (11) connected to the compressor for supplying pressurised air to a manifold (11A), solenoid valves (12) for controlling the air flow to air outlets (13) in a communication with a pressure cuff or cuffs (not shown).

Figure 2 demonstrates a practical working embodiment of the invention comprising a system for rapidly delivering providing pressurised air to one or more therapeutic pressure cuffs (not shown). This improved rapid inflation system includes a relatively low power air compressor (20), an air supply hose (21), solenoid operated air valves (22) for controlling the air flow from a distribution manifold (22A) and air outlets (23) to a pressure cuff or cuffs (not shown). The embodiment also includes a pressurised chamber (24) for storing and rapidly releasing pressurised air, a primary air feed solenoid valve (25), data transfer cable (26), a compressor control means printed circuit board (PCB) (27), and a pressure switch (28). Although not shown, the solenoid operated air valves (22) are also linked to and controlled by the control means (27).

In one method for use, the low power compressor (20) fills the pressurised chamber (24) to a pre-determined pressure at which point the solenoid (s) (22) for controlling the air flow release the pressurised air into the cuff(s) (not shown) connected the pressurised air outlets (23) and the patient begins treatment. Pressurised air flow distribution and control is effected by the compressor control PCB (27) that controls the primary air fed solenoid valve (25) via the data transfer cable and commands the low power compressor (20) using data from the pressure switch (28).

Operation The Control PCB is connected to a power supply. There is a microcontroller on the PCB which monitors the pressure switch on the air tank and also reads the pressure in the cuff. Also there is a switch to turn on and off the compressor.

When the tank pressure is below the set pressure, e.g. 150mmHg, then the compressor is switched on and fills up the tank with pressurised air. A typical cycle time for the inflation and deflation of the cuff would be 60 seconds. The inflation cycle would be 15 seconds and the deflation 45 second and go up a pressure of 40mmHg.

At the start of the inflation cycle the Control PCB switches the air solenoid valve on, which allows air to pass from the tank into the cuff. During this process the pressure transducer is used to monitor the pressure in the cuff. As soon as the PCB senses that the pressure has reached 40mmHg it switches off the air solenoid valve. During this cycle the air tank pressure will have dropped and the compressor will be turned on to re-pressurise the tank as quickly as possible.

Once the inflation time has completed its 15 second cycle the air solenoid valve will vent the cuff to atmosphere for the next 45 seconds.

This cycle would repeat every 60 secs on a 24/7 basis.

Benefits It is widely accepted that the quicker the cuff can be inflated up to pressure the better the pulse of blood within the calf, and the present system can provide for rapid cuff inflation.

This process allows a very low output and thus quiet compressor to be used, instead of a large noisy compressor.

The economics are significantly reduced whilst the therapy is improved.

Claims

CLAIMS1. Pressure cuff inflation system comprising an airflow circuit for inflating one or more pressure cuffs, said circuit comprising an air compressor in communication with a pressurised air distributor having one or more outlet ports adapted to communicate with air pressure cuff(s) when fitted to said distributor, valve means for opening and closing the port(s) to receipt of pressurised air, a pressurised air reservoir arranged to accumulate air pressurised by said compressor and to discharge that pressurised air into the said pressurised air distributor, primary control means for controlling the pressure of air that accumulates within the reservoir and secondary control means for controlling release of pressurised air from the reservoir into the said distributor.
2. A system as claimed in claim 1 wherein the reservoir is located in the airflow circuit between the compressor and the distributor.
3. A system as claimed in 1 or 2 wherein a further valve means is provided in the airflow circuit between the reservoir and the distributor.
4. A system as claimed in any preceding claim in which the primary control means comprises a pressure switch linked to the compressor to activate the compressor upon the pressure in the reservoir reaching a predetermined threshold.
5. A system as claimed in any preceding claim wherein the compressor is linked to a controller that activates said secondary control means.
6. A system as claimed in claim 5 when dependent upon claim 4 wherein the reservoir pressure switch is linked to said controller and/or to said secondary control means.
7. A system as claimed in any preceding claim, substantially as herein described.
8. A system as claimed in any preceding claim, substantially as herein exemplified in any described embodiment.
9. A system as claimed in any preceding claim, substantially as herein illustrated in Figure 2 of the accompanying drawings.