WO2007115569A2

WO2007115569A2 - Supervision system for decubitus prevention

Info

Publication number: WO2007115569A2
Application number: PCT/DK2007/000165
Authority: WO
Inventors: Ole Ilum Christensen
Original assignee: INSPIRI APS
Current assignee: INSPIRI APS
Priority date: 2006-04-07
Filing date: 2007-03-30
Publication date: 2007-10-18
Anticipated expiration: 2008-10-07
Also published as: WO2007115569A3; DK200600501A

Abstract

The invention consists of an alarm system. The visual or acoustic alarm system consists of a pressure relief air cushion (figure B - 2b) mounted on a rest or wheel chair (figure B - 3). The air cushion is equipped with sensors (figure B - 4) for measuring pressure, temperature and humidity, including a control box (figure B - 5) for the regulation of the sensors in question. The cushion is divided into one or several sections (figure B - 6). The pressures (figure A - 9) of the sections are read in connection with a sitting-posture analysis (figure A - 8). In case of a variation of the pressures of the sections, the control box ensures the call of an alarm and regulation of pressures. A special model is connected to an electric pump (figure B - 7) and a PLC (figure C - 20). The electric pump alternates the pressures of the sections. Consequently, the chair has a massaging effect, and the blood circulation is increased. Furthermore, an air condition system (figure B - 21) is connected in another special design. The control box (figure B - 5) and the air condition system (figure B - 21) will call alarms and regulate the relative humidity around the sensors (figure B - 4b) and (figure B - 4c). This ensures optimum conditions for the well-being of the patient as well as optimum blood circulation. The invention is particularly suited for the prevention of pressure ulcers (decubitus ulcers) (photo 1- figure 1).

Description

Supervision system for decubitus prevention

The invention concerns an instrument and a method of alarming the external circumstances of a pressure or bedsore, before it starts (prevention) or after it has started (restoration). Pressure or bedsores - decubitus ulcers - break out on persons, (photo 1), who for a period of a disease or due to a permanent handicap have reduced locomotive or mobility power. The alarm call is visual or acoustic.

Due to his or her reduced mobility, the person in question is strongly attached to his or her bed, rest chair or wheel chair, (photo 2). A nursing person, doctor or nurse attends the patient for pressure ulcers and enters data in a medical record.

Caused by the patient's reduced mobility and the consequent reduced blood circulation, a significant risk of the possible formation of a pressure ulcer, decubitus ulcer, will arise. The sore results from the effect on the skin, due to pressure, friction, shear, humidity and heat.

The body liberates heat as a combination of evaporation, perspiration and heat conduction to the air by way of thermal radiation.

The evaporation of perspiration from the skin is reduced in case of a high humidity of the atmosphere, and the efforts made by the body in order to maintain an acceptable body temperature will become considerably hindered.

Likewise, if the atmosphere is just as warm as or even warmer than the skin at a high humidity of the atmosphere, the blood, which is taken to the surface of the body, cannot liberate heat by conduction to the surrounding air, and a situation called hyper-pyrexia will arise.

As a lot of blood has been conducted to the external surface of the body, relatively less blood will be conducted to active muscles, to the brain and to other internal organs. The physical strength is reduced, and tiredness will arise quicker than normally. Allergy and the mental capacity may also be affected. The emerged situation is called heatstroke or hyperthermia. "The US Environmental Protection Agency" quotes ASHRAE Standard 55 - 1992 "Thermal Conditions for Human Occupancy" for keeping the relative humidity between 30% and 60%, but below 50% in order to control dust mites.

In case of a high humidity of the atmosphere, perspiration is less effective, and consequently we feel warmer. At ambient air temperature, dry air feels colder, which results in discomfort, low productivity and a need for more heating.

In case of low blood circulation, the skin is more sensitive to mechanical effects such as pressure and shear.

Dependent on the relative size of the reduced mobility of the patient, and the consequent danger of generating pressure ulcers, a physical pressure relief aid is to be selected in order to prevent the generation of the sore, such as a mattress or a sitting cushion, Photo 3.

The sore is generated from the eye of the hurricane. Photo 4 and typically, it has 5 stages:

In the light of a risk assessment of the patient's reduced mobility, a pressure relief aid is to be chosen.

Presently, the Braden scale with values from 6 to 23 is the preferred risk assessment at hospitals and nursing centres.

The invention deals with pressure relief aids of the medium and high risk zones according to the Braden scale score 6 - 15 up to 18.

The pressure relief aids are mattresses or cushions filled with air, Photo 3, divided into one or several independent sections with cells filled with air.

Social costs for examinations, risk assessments and treatments as well as choices and purchases of pressure relief aids are very heavy and increasing. The risks of generating pressure ulcers at an average hospital are 30%. (Source: epuap). At European level, an organisation called European Pressure Ulcer Advisory Panel EUPAP (www.epuap.org^') has been founded in order to control and reduce the growing social costs. The organisation's intention is to exchange experiences and to develop new knowledge of treatment.

Description of the related art

The described field is subject to quite a number of invention activities.

It is a well-known fact that WO 2005/011555 Al has built-in power sensors, which measure a critical lowering of the patient in the cushion or the mattress.

A pump is to be activated in order to suspend the lowering, when the critical lowering occurs.

Also US 6, 154905 builds in a sensor in order to control the deformation of the cushion or mattress. When a foam stick has been deformed up to a fixed limit, an alarm signal is to be sent out.

US 2005/0022308 deals with a multiple layer mattress, which removes heat and humidity from the patient.

ROHO describes in details in WO 2006/116667 a "Proximity sensor", which can determine the distance of the patient from the sensor in connection with a fixed critical lowering.

An alarm will start, when the fixed critical lowering is exceeded, and a compressed-air tank adjusts the lowering.

The new idea of the present invention is the fact that it consists of a monitoring, alarming and curing system, constructed around a pressure relief aid. In order to ensure optimum blood circulation, the existing values of pressure (mbar), temperature (C) and relative humidity (%RF) of the geographical area with a risk of pressure ulcers, decubitus ulcers, are to be measured and adjusted.

Brief description of photos and drawings

Figure 1 shows pressure measuring at a sitting-posture analysis

Figure 2 shows a principle sketch of the alarm system

Figure 3 shows a system of alternating pressure

Photo 1 shows a patient with pressure ulcer

Photo 2 shows a wheel chair

Photo 3 shows a "snowball" air cushion

Photo 4 shows the eye of the hurricane of the pressure ulcer

Photo 5 shows a sitting-posture analysis

Photo 6 shows a pressure relief diagram

Photo 7 shows a prototype of the alarm system

Photo 8 shows a commercial design of the alarm system Written description of the best mode for carrying out the invention

The present invention deals with a pressure relief aid. The invention includes a sitting-posture analysis, (figure 1), with a subsequent pressure measuring of the sections of the pressure cushion (figure 1. 2a).

The pressure relief situation of the sitting-posture analysis is read by way of a pressure carpet, photo 5, and a personal computer with software (figure 3, 19) and is to be printed in a pressure relief diagram, photo 6.

A pressure relief cushion with measuring sensors is designed on the basis of the pressure relief diagram and the pressure measuring (figure A - 9) in order to solve the individual relief needs of the patient in question.

The cushion (figure 2, 2b) or, if necessary, more cushions are equipped with sensors (figure 2, 4).

In order to measure pressure, temperature or humidity, the sensors are connected to a Control-box (figure 2, 5)

The cushion (figure 2, 2b) is mounted on a rest or wheel chair, photo 2.

The control box (figure 2, 5) is also mounted on the rest or wheel chair.

Furthermore, an electric pump (figure 2, 7) is mounted on the rest or wheel chair. Some other form of energy may also operate the pump. A hand-powered pump is used in a special application.

By way of the pump (7) the control box controls that the pressures of the sections measured with the pressure sensor (figure 2, 4a), are in accordance with the pressure measurement (figure 1, 9) within a given range of tolerances, which has been determined during the sitting -posture analysis, (figure 1). If the pressure relief cushion is divided into several sections, the pressure is to be measured and controlled in each individual section.

In addition to the pressure control and the alarm for pressure changes, the control box gives alarms for changes of humidity and temperature, if the range of tolerances has differed.

Sensor (figure 2, 4a) measures pressure. Sensor (figure 2, 4b) measures temperature. Sensor (figure 2, 4c) measures humidity.

Changes of humidity will frequently occur in connection with incontinence and emission of heat.

According to the described, the invention consists of a system consisting of an air cushion (Figure 2, 2b), sensors (figure 2, 4) and a control box (figure 2. 5) for controlling the differences in pressure (figure 1, 9). In a special design, the pressure can be controlled by way of a hand pump.

In a preferred design, the monitoring system is additionally equipped with an electric pump (Figure 2, 7), which after the activation of a magnetic valve (figure 3, 10) is capable of supplying or removing air from the sections, in order that the pressure (figure 1 , 9) is increased or lowered respectively.

The monitoring system of another preferred design is equipped with an alternating pressure system, which from a PLC programme varies the pressures of the sections (figure 1, 9).

The varying and alternating pressures (figure 1, 9) of the sections have a massaging effect and contribute to an improved blood circulation and consequently, they have a curing effect.

In a user- friendly design of the alternating pressure system, the PLC is connected to a personal computer with software. Thus the hospital or the nursing staff can directly program a treatment of massage in accordance with the extent of the pressure ulcer over the five stages. According to the described, the invention consists of alarm and parameter control and regulation at three levels:

• An alarm system with manual air supply.

• An alarm system with automatic inlet or outlet of air.

• A system of alternating pressure with programmable inlet or outlet of alternating pressure, figure 3.

Furthermore, designs may be invented as a combination of the three systems in question.

The fundamental system, shown in figure 3, and a prototype, photo 7, consist of:

Cushion sections (figure 3, 6), equipped with sensors (figure 3, 4), pressure monitor (figure 3, 11), magnetic valve (figure 3, 10), valve block (figure 3, 13), safety valve (figure 3, 14), magnetic valve pressure (figure 3, 15), magnetic valve vacuum (figure 3, 16), filter (figure 3, 17), pump (figure 3, 7), PLC (figure 3, 20), display for reading values (figure 3, 18), personal computer with software for programming of alternating pressure (figure 3, 19).

Schematically the systems can be illustrated in the following way:

It may be connected to an air condition system (figure 2, 21) for control of pressure and temperature.

In a future model of the alarm system, each of the cells of the cushion sections will form its own controlled pressure section.

The individual cushion cells will be made of rubber, plastics or such materials as thermoplastic elastomers.

Claims

PATENT CLAIM

1 Monitoring, alarming and curing system characterised by the fact that it includes a pressure relief aid, air cushion or mattress with one or several sections.The pressure relief aid is equipped with sensors for measuring of present values of pressure (mbar), temperature (C), humidity (% RF) and a control box. The pressures of the sections are determined and measured in connection with a sitting- posture analysis. The control box gives the alarm for differences of the set values for pressure, temperature and humidity.

2 The alarm system in accordance with claim 1 is characterised by the fact that an electric pump controls automatically differences of the set pressures of the sections.

3 The alarm system in accordance with claim 1 and claim 2 is characterised by the fact that the electric pump is connected to a PLC, which is programmed for changing the pressures of the sections.

4 The alarm system in accordance with the previous claims is characterised by the fact that the PLC is connected to a personal computer with software for the programming of the changing pressures of the sections.

5 The alarm system in accordance with the previous claims is characterised by the fact that an air condition system controls presently set values of temperature and relative humidity.