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Saving Lives One Breath At A Time
In 1949, the bioengineer Basil Martin Wright joined the Medical Research Council pneumoconiosis unit at Llandough and was assigned the responsibility of inventing a medical instrument that would measure the lung function of asthma patients. The peak flow meter he patented was used for patients participating in large-scale studies and was not portable.  In 1970, a miniature version was developed. It became standard medical equipment in doctors’ offices and could be used by asthmatics to self-monitor their breathing. Three years ago, doctors and scientists began to question the accuracy and consistency of peak flow meter readings. A recent study shows there can be a 15% inaccuracy in readings across a variety of peak flows which is causing the medical field to now demand a standard calibrating system.

Before the invention of the pulse oximeter, doctors had to rely on the tinge of their patients’ flesh to determine the oxygen level of their patients’ blood.  If the skin color became a bluish tint, doctors knew their patients’ oxygen level was low indicating the patient was in trouble.   After Carl Matthes’ invention of the oximeter (ear probe) in 1935, doctors were able to continually observe the oxygen levels in their patients’ bodies in a non-invasive manner. Thirty-five years later, in 1970, Hewlett-Packard scientists found that an ear oximeter was much more precise if the ear tissue was heated to 41 C.  By 1974, Takuo Aoygai had figured out that oxygen saturation could be measured by sending light through the tissue.  In 1978, William New, MD, PhD invented the prototype for modern pulse oximetry.  He discovered that infrared and red light could be used to measure the color of the blood.  The more oxygen that is present, the redder the blood appears.  The latest breakthrough in pulse oximetry came last year when David Benaron, MD, a professor at Stanford University, significantly improved the device by enabling it to work even when a patient had no pulse. 

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