Class: BE209
Group: R2
Members: Rajeev Siripurapu, Ankita Deshpande, Anya Litvak, Karen Rudo,  Nancy Huang,  Grant Arnold
Date: December, 2002

Full Text

Introduction:

The possible dangers of fever in infants are well known.  Because an infant’s immune system is still fragile and not fully developed, the effects of seemingly minor infections are magnified in a young child.  Many infections present themselves in infants as fevers without the traditional accompanying symptoms.  In a study conducted at the Tripler Army Medical Center, Honolulu, during a one-year period, 41% of febrile infants were confirmed to have a viral infection and 15% had a confirmed bacterial infection.  Urinary Tract Infections were the most common bacterial infections, occurring in 75% of those infants with confirmed bacterial infections.  However, in the majority of the UTI cases, the infants presented only with a fever and without the usual associated pyuria (the appearance of white blood cells in urine) . Another danger of high fever that is unique to infants is febrile convulsions.  In addition, there is preliminary evidence suggesting that, in a minority of cases, febrile seizures can possibly lead to hippocampal injury .
While most parents are aware of the dangers of fever in their infant, many do not know when their child’s elevated body temperature calls for no action, a dose of Tylenol, or a trip to the emergency room.  Thus, many parents might find helpful a device that would constantly monitor their infant’s temperature and alert them as to the medical danger associated with that temperature.  Furthermore, because febrile seizures are correlated with a sharp increase in body temperature, it is imperative for parents to have a device that can alert parents to a rapidly rising temperature.
An Electronic Temperature Monitor (ETM) that meets the aforementioned needs can be created using a window comparator circuit containing a thermistor.  By using a window comparator circuit, parents can see that their infant’s temperature is a) normal, b) slightly elevated, or c) critical. Thus, the device can serve as a guide to parents as to what action to take to remedy their sick child.
However, in order for this device to be an effective consumer product, it must meet certain criteria.  First, the ETM must be portable and function on a readily available power source such as a 9v battery.  Secondly, since it is a continuous monitoring device, the circuit must not drift, as drift will affect the accuracy of the determined temperatures and thus the accuracy of the device.  Thirdly, since the ETM would theoretically be attached to the underarm of the infant, there is possible exposure to the air in the room.  Thus, the device should not be affected by fluctuations in ambient temperature.  Finally, the rooms of most infants are equipped with several electronic devices that could produce error-causing electronic noise.  Such noise should not adversely affect the accuracy of the ETM.