Garments That Help Doctors Monitor Your Health!
Clothes that tell the doctor just how healthy you are? This isn’t a scenario from 2050. Pretty soon, your wardrobe could well dictate what your doctor prescribes!

the health of some people requires continuous monitoring because of their delicate or critical condition, as well as for the academic value of understanding physiological behaviour. Such monitoring requires patients to be continually connected to instruments and hence remain stationed in one location, as remote monitoring of physiological parameters is not possible with the medical instruments in one location and the patient in another.
healthy_garmentsWireless monitors such as those for cardiac applications have been in use for quite some time, but monitoring body fluids like sweat and blood on a continuous basis is essential in some cases. The analysis of sweat helps in detecting pathological problems such as hyperhidrosis, glycemia, hyperthyroidism, etc, and physiological states such as extreme activity or menopause. The pH of sweat can be used to infer the activity levels of sportspersons, and metabolic states of diabetics and the obese. Monitoring blood will reveal the oxygen content and thereby result in an early detection of hypoxemia (a condition in which the oxygen content of blood is low). The healing process of a wound can be tracked by monitoring the C-reactive protein levels in the vicinity.

Scientists have now come out with innovative clothes that allow people to monitor body fluids such as blood and sweat. These novel garments come with biosensors (see box) that monitor these fluids.

Bio sensational!
Sensors have been used in clothes for some time. Examples include the use of heaters in ski boots, gloves and avalanche detectors. Biosensors operate on the principle of recording the change in electric potential, pH, colour, capacitance, reflectivity, etc Microsoft MCTS Training.

An innovative mix of hydrophilic and hydrophobic yarns suitably woven into the garment, functions like pumps and direct very small quantities of sweat to the sensors. The two layers of textile can serve as a capacitor. The sensor can use colorimetry to detect pH or voltammetry to detect the concentration of electrolytes like sodium, potassium, etc. Plastic optical fibres are woven into the part of the garment that covers the chest. These fibres increase the amount of light transmitted as well as reflected, and thereby the amount collected by the oximeter. Another advantage is that the measurement of oxygenation is best done over the chest rather than the fingertips and earlobes (where signals are not strong). The person is also comfortable as this is part of a regularly worn garment.

A hydrogel that changes its pH and refractive index in response to locally concentrated protein can be used to track the healing of wounds. Typically, when a wound heals, the concentration of C-reactive protein in the vicinity of the wound varies, effecting a change in pH. The hydrogel responds to this variation, which can be measured. This hydrogel can be made part of a sensor (about 0.2 cm2 in area) and woven into wound dressings and bandages. Of course, the recording of pH requires portable electronic equipment. This monitoring will be useful for patients suffering severe infection.

The Swiss Centre for Electronics and Microtechnology (CSEM) has been conducting research on developing garments into which textile-based biosensors can be woven/fitted and has completed three pilot projects titled, Wealthy, Biotex and Proetex in this field.

Challenges for biosensors
Although there is no doubting their convenience, there are a number of challenges that need to be overcome if biosensors in fabrics are to realise their potential. Some of the key ones are mentioned below Microsoft MCITP Certification.

Measurement of parameters: The average adult sweats about 500 to 700 ml/day under mild weather conditions. Depending on the environment (high humidity, inside a sauna) and activity (jogging or bicycling) the amount and rate of sweating can be higher. However, considering the average body surface area of about 1.7m2, the rate of sweat over an area is small. Also, this depends on the part of the body. This small quantity poses a big challenge while measuring the required parameters.

Additionally, how does one collect and transport the fluid from its source to the sensor? Does the sensor need an external source of power? How will the analysis be done in real-time? What is the mechanism to store the data? How will it be transmitted to the investigator and the wearer either as an alert to act upon or as a warning to take note of? These are just some of the questions that need to be answered.

Designing clothes: The garments fitted with these sensors should be fashionable and still retain their functional capabilities. The sensors should not impede the natural drape of different types of fabrics, nor the design and style of the garments.

Data collection: In any situation, the sensor only senses the state/signal/stimulus of a system. This signal must be translated into a measurable quantity using a transducer, then displayed, recorded, stored, processed and transformed into a parameter that accurately reflects the state of the system. In some situations, these parameters need to be further transmitted and processed (post-processing) into easily readable forms such as graphs and charts. IT plays a vital role in all these stages, except the translation of the signal using a transducer.

In the case of fabrics, these sensors have to be tiny and so cannot have adequate storage capacity. The measurements can be transmitted to a nearby source using Bluetooth (for short ranges) or Wi-Fi (for long ranges). There it can be stored and sent via GPS or Internet to any other location of choice. With the progress of technology, measured data may even be displayed on handheld devices, including cell phones and PDAs.

Notwithstanding all these challenges, the day is not too distant when data will be sent to the doctor who interprets them and remotely changes the dosage of the medication (as in the case of diabetic patients). Who knows, the next time you visit the doctors, they may ask you to wear a particular outfit on the days you have to take the tests. Whoever said that clothes make the man clearly had not reckoned that they would one day also help in making better prescriptions.