Reading your oxygen levels,

Pulse Oximeter is a Valuable Tool

In the old days, the only way to know what your oxygen levels were, was to draw an arterial blood sample, an invasive procedure. (Invasive means entry into the body by cut- ting or by inserting an instrument.) In 1935, a German physician developed the first ear oxygen saturation meter. Pulse oximetry was developed in 1972 and introduced for commercial distribution in 1981. Originally, it was used in the operating room to monitor oxygen levels. Its use expanded to the re- covery room, intensive care units, neonatal nurseries, physician offices and eventually to oxygen users themselves. In 2009, Nonin Medical (the name Nonin came from non- invasive) introduced the first Bluetooth- enabled oximeter, which allowed health clinicians to be able to monitor readings remotely.

There was quite a concern among pulmo- nary physicians about their patients having their own oximeter. Many felt that people would become obsessed with looking at their readings and they would be over- whelmed with calls every time there was a low measurement. Instead it has become a very valuable tool to involve the oxygen user in their own course of treatment.

The reading from your oximeter displays the percentage of blood’s hemoglobin that is loaded with oxygen. Normal ranges for people without pulmonary pathology are from 95 to 99 percent. It utilizes a processor and a pair of small light-emitting diodes. Oxygenated hemoglobin absorbs more infrared light and allows more red light to pass through. The reading is a result of the processor cal- culating the ratios of the light absorbed.

There are several things that can affect your readings:

  •  blood pressure can make it difficult for the sensor to pick up the blood flow.
  •  hands can cause the pulse oximeter to give inaccurate readings.
  •  you have anemia – low hemoglobin – your readings will be affected.
  • hemoglobin is a form of hemoglobin that does not carry oxygen. You normal- ly have 1% to 2% in this form. Higher levels would cause a pulse oximeter to have a reading of around 85 percent regardless of the actual oxygen satura- tion level. Higher percentages can be genetic or caused by exposure to certain chemicals and medications.
  • oximeter cannot distinguish the differences between carbon monoxide and oxygen on the hemoglobin molecule. If 20 percent of hemoglobin has carbon monoxide and 75 percent has oxygen, the reading would be 95 False readings will result in people with smoke inhalation, carbon monoxide poisoning, and heavy cigarette smoking.
  • polish, especially  purple  or  black polish, will make readings difficult.
  • right light   in   the   room   that   you are using the oximeter can affect readings.