Hematocrit monitor

Area of Science:

• Biomedical Engineering
• Optical Sensing
• Veterinary Medicine

Background:

• Accurate monitoring of hematocrit (Hct) is crucial in clinical settings, particularly during surgical procedures.
• Existing methods for Hct measurement can be invasive or time-consuming.
• Developing non-invasive optical methods for real-time Hct monitoring is an area of active research.

Purpose of the Study:

• To experimentally determine the optimal incident visible wavelength and light detector angle for maximal optical density change between Hct levels of 20% and 40%.
• To establish parameters for an effective fiberoptic biosensor for Hct monitoring.

Main Methods:

• Utilized a universal monochromator to select incident wavelengths in 8-nm increments across the visible spectrum.
• Employed a motorized shuttle for reproducible sample placement (20% and 40% Hct) between the light source and photodiode detector.
• Tested light detector angles of 30, 90, and 180 degrees relative to the incident beam.

Main Results:

• The greatest change in optical density between 20% and 40% Hct was observed at a wavelength of 624 nm.
• An optimal light detector angle of 90 degrees was identified, independent of sample cell or detector profiles.
• These parameters were successfully applied in a fiberoptic biosensor for Hct monitoring in dogs.

Conclusions:

• The study successfully identified optimal optical parameters (624 nm wavelength, 90-degree detector angle) for Hct measurement.
• These findings enable the development of a more accurate and efficient fiberoptic biosensor for Hct monitoring.
• The validated biosensor shows promise for real-time Hct tracking in canine surgical patients.