___ reflects tissue oxygen tension and relies on a balance between oxygen supply and consumption
Transcutaneous Oximetry TcPO₂
Wound healing and amputation level determination is a capability of ____
Two limitations of Oximetry are___
the inability to keep the electrode fairly flat on the skin surface;
electrode placement must be on intact skin.
In Oximetry testing the patient position should be
supine, head slightly elevated, room warm.
What are the physical principles of Oximetry ____
An electrode heats the skin to 45℃;
blood flow increases---lipid layer in fatty tissue melts---More "O₂" escapes through skin, measured by sensor in electrode;
As "O₂" escapes, a chemical reaction occurs in electrolyte solution, located between skin and electrode surface;
Electrode converts chemical reaction to a "current" reading which is converted to a pO₂ reading in mmHg.
Describe the technique of Transcutaneous Oximetry TcPO₂ __
Skin is cleansed with alcohol wipe and air dried;
Airtight self-adhesive fixation ring is placed on the skin;
A few drops of electrolyte solution is put inside the ring;
The electrode/sensor is affixed to the fixation ring.
A reference reading (upper Lat chest) obtained first; followed by specific sites (eg near toes, BK, AK);
After manual calibration, it takes approx 15-20 min per site to obtain "pO₂" reading.
Oximetry interpretations vary with manufacturers, but generally healing should occur with a pO₂ reading of ____
70 - 80 mmHg
In oximetry, borderline healing is
30 - 40 mmHg
In oximetry, non healing (poor values) occurs with
10 -15 mmHg