BACKGROUNDIn the past, the need to measure thehydration level of body was not that much severe as it is now, so nothingprominent was being present to check the water level in our body to avoiddehydration issues but with the passage of time as we feel a need to check ourhydration level to maintain required water level in our body different methodswere being introduced by different scientists. Among those few options arephysical signs and symptoms, plasma/serum osmolality, urinary parameters andsaliva osmolality. All of these techniques were more or less the invasivetechniques i.e. Plasma osmolality is one of the good one to measure thewater level in our body but requires an invasive blood sample and will notidentify extracellular dehydration (e.
g. diarrhea, diuretic administration etc.).Urinary marker is better with chronic fluid losses (e.g. prolonged fluid restriction)but has been shown to have poor diagnostic accuracy in elderly hospitalizedpatients.
Saliva may be an alternative in such a case to overcome thedifficulties being faced in above two cases but it also have some diagnostic accuracyissues which were being resolved by making them function altogether in anexpected way. As the time passes and different development intechnology takes place monitoring of important biological processes of thehuman body becomes one of the current concerns of personal medicine to ensurehealthy and long life expectancies. Excessive dehydration has negative impact onhealth and also causes physical problems. In this case body water could loss upto 2% of the weight and can increase the risk of heat stroke.
This can be a lotsevere for those working/competing in hot environments (i.e. athletes, fire fightersand military officers etc.).
Many techniques are available to assess the waterlevel of body as discussed above but it isn’t clear uptill now to identify thebest one. Blood osmolality is considered the best uptill now but it alsorequires an invasive method (i.e. blood sample). Due to the fact that nothingwas found to be the quickest and completely reliable method so the interesttowards non-invasive techniques starts to develop that would be fast, easy touse, inexpensive and accurate method to measure the exact hydration level ofthe body.
A lot of research has been done in this context to develop someeasy to use non-invasive methods of measuring water level. One of thenon-invasive method is determination of potassium content in urine (potassiumcontent has inverse relation with water level in the body). This method alsohave some difficulty as we require the sample to be tested to say anything aboutthe water level in the body, so the need arises to make something which can easilybe used by elderly through which they can get to know when they need a glass ofwater to remain hydrated. From this point of view, interest in wearable,portable and hand-held sensors to provide health monitoring functions has increasedin the last decades. INTRODUCTIONFor one’s body to work properly required level of water must bemaintained.
Dehydration occurs when the water level falls below the requiredlevel. It happens mostly when intake of water is less than the water depleting.Mostly young children, infants and older adults face this problem ofdehydration. Common causes of dehydration are sweating, headache, vomiting andconstipation.
Quantitative measurement of the water level in a body is a bitdifficult task and it can be related with the one’s working in hot environmentslike athletes, fire fighters etc. For avoiding any serious health problem amicro-sensor can be used on the skin that can give them an indication of lowwater level in their body.Few people might think that as soon as they feel thirsty they wouldtake some water and easily avoid the possibility of dehydration but this is notthe case because there might be a possibility of getting dehydrated beforehaving a thirst for water. And this issue is very severe in case of elderpatients. So, to maintain that required water level and avoid any criticalsituation we must utilize the dehydration sensors which detects the amount ofwater level through different means (PH, perspiration, dryness of body etc.) andwill let you know about your condition before going through excessive waterloss.By goingthrough several means of measuring water level, prototypes of different sensorswere being made by the researchers which includes wearable smart phone enabledwatch, dehydration detecting diaper pad, wrist worn sensor that uses tinyneedles, dehydration alerting urinal and a watch that measures dehydrationusing light. IMPORTANCEThe non-invasive methods kept a lot of importance in present worldfor measuring water level in a body because it can be used by the ones workingin hot environments.
One of the dehydration sensors i.e. Perspiration baseddehydration sensor is important in a way that as soon as the sweat comes incontact with the sensor it will generate an electrical signal and send it toactuator that will let us know the amount of water level in our body and willprotect us from dehydrating.If anyone (especially elderly patients) won’t be aware of the waterlevel condition and don’t drink excessive water to remain hydrated then thereare chances that they might get dehydrated and will suffer from short term effectsi.e. irritability, short term memory and headaches etc.
Along with these shortterm effects, dehydration also has some long term effects on kidney, heart function and gastrointestinal thatmajorly contributes to constipation, chronic heart disease and kidney disease.