Optimization and control of therapeutic equipment for brain hyperthermia treatment

Project Title

Optimization and control of therapeutic equipment for brain hyperthermia treatment

Project Area of Specialization Biomedical EngineeringProject Summary

We know that brain control the functions of various natural organs and components of human body.Hypothalamus is the part of brain that controls the body temperature and release hormones. It keeps up a homeostasis through thermoregulation. However, due to heat stroke and cardiac arrest which may carry the body to a neurotic state called hyperthermia. Depending on intensity of disease, the treatment is crucial and required an emergency treatment. Hyperthermia is an overheated state of body, where the center temperature raises 40oC. In hyperthermia there are dangers of disability of indispensable organs, obviousness, and trance like state in serious cases. The treatments primarily depend on pharmacology, but not suitable due to time delay because we require emergency treatment. In such circumstances, a physical cooling therapy may provide an appropriate treatment for this situation.

Wakamatsu et al.[1] performed many experiments over the hyperthermia therapy based on air and water-cooled blankets. The therapy was based on fuzzy-based algorithm using induced hyperthermia characteristics.

Gaohua and Kimura,[2] excludes the pathological parameters such as oxygen consumption rate, blood ?ow rate, and partial pressures of O2 and CO2. It is important to that the real body-temperature characteristics are nonlinear functions of a fore mentioned parameters and therefore are not truly represented by simpler ?rst-order models.

The components needed for control are controller and control valve. For best performance the controller designing should accurate.We use thermocouples for measuring temperature. Hard PVC (polyvinyl chloride) or ABS (acrylonitrile butadiene styrene) pipe is better than soft PVC to get required shape (in the form of helix). There are different configurations of orifices in tubes for throwing of cool air and use best geometry for this purpose. The best suited orifice for laminar flow among number of different options is rectangular orifice inclined at different angular positions to assist the exiting fluid. The incident flow on mannequin is corresponding to angular position of orifice. We will use rectangular geometry of orifices at different patches.

Project Objectives

The objectives for the development of this project are:

• Control compressed air flow using a pneumatic valve automatically than manually.
• Temperature Control of human body using feedback sensor,air flow circuit and controller
•  Choose the best material for helix shape heat exchanger coils with possibility of orifices design.
• Select the best geometry for orifices cut and working air flow.

Project Implementation Method

As we cannot use human body in project because of ethical constraint like OHRP. So we use a mannequin in place of human body and perform experiment on it by using thermal law and characteristics. We take dimension of this mannequin as length =1.7m and area =1.8m2. The cool air is approximately 26 ºC and the air velocity <2ms-1.

Mannequin’s temperature is raised (at 40 – 44 oC) by circulating hot working fluid in a body.

The hot working fluid will pass through mannequin’s core through different patches (each patch represents the specific part of mannequin’s body i.e., head, upper body, lower abdomen part and lower legs). In order to achieve uniform thermal gradient, the valves are controlled accordingly. Then this hot working fluid will be returned to the reservoir. Thus, a continuous supply of hot working fluid will increase the temperature of the mannequin’s core to induce hyperthermia characteristics.

Figure 1: Work flow

Now for lowering the temperature of mannequin there is a separate mechanism in which cool is distributed through network as shown below.

Figure 2: Work flow

Use thermocouples to measure the temperature of the mannequin. The value of temperature can be used as the feedback variable for control valve, in such a way that the control valve will adjust the internal openings according to the temperature of mannequin’s body. Once the mannequin’s body temperature is lowered to certain level by the spray of cool air, the valve will be shut off or spray the air slowly.

Temperature

Controller

Valve

Air

Figure 3: Work flow

Here we use the controller to control the valve, the controller take feedback from the valve of temperature and spray the cool air to decrease the temperature of mannequin according to required value. We can use any microcontroller for this purpose like Arduino, raspbery pi etc.

Temperature

Controller

Valve

Air

Benefits of the Project

Application of the Project:

• Cardiac Arrest.
• Cancer tumor.
• Brain Hemorrhage.
• Heat stroke.

Technical Details of Final Deliverable

Final Deliverable of the Project Hardware SystemCore Industry HealthOther Industries Medical Core Technology OthersOther TechnologiesSustainable Development GoalsRequired Resources

Controller