Method for evaluating skin hydration and fluid compartmentalization
There is provided a system and method for evaluating skin hydration and fluid compartmentalization. The system includes a microneedle array configured to extract fluid from an interstitial space and a pressure sensor configured to measure a pressure differential between the interstitial space and ambient pressure during extraction of the fluid. A processor coupled to the pressure sensor is configured to compute a hydration index based on the pressure differential. A display coupled to the processor is configured to display the hydration index.
1. A method for determining hydration comprising:
extracting fluid through microneedles inserted into skin;
determining the pressure gradient required to extract the fluid; and
determining a hydration index based on the pressure gradient.
2. The method of claim 1 , wherein the hydration index is representative of the hydration of the skin.
3. The method of claim 1 , wherein the hydration index is representative of the hydration of the body.
4. The method of claim 1 comprising combining a skin thickness value with the pressure gradient to determine the volume of a compartment of the skin.
5. The method of claim 1 comprising measuring blood specific analytes in the fluid to determine leakage from a vascular compartment.
6. The method of claim 5 wherein the blood specific analytes comprise albumin or other plasma proteins.
7. The method of claim 1 comprising measuring inflammation-specific analyte concentration.
8. The method of claim 1 comprising measuring intracellular-specific analyte concentrations to assess the contribution of intercellular fluid.
9. The method of claim 8 wherein the measuring intracellular-specific analyte concentration comprises measuring potassium concentration.
10. The method of claim 8 comprising quantifying the extent of cellular trauma in response to insertion of microneedles based on the contribution of intercellular fluid.
11. The method of claim 1 , wherein determining the hydration index based on the pressure gradient comprises determining whether the fluid has a positive pressure differential relative to ambient pressure.
12. The method of claim 1 , wherein determining the pressure gradient required to extract the fluid comprises measuring the amount of pressure required to extract the interstitial fluid.
13. The method of claim 12 , wherein determining the hydration index comprises correlating the measured pressure required to extract the interstitial fluid with a volume of free fluid in an interstitial space.
14. The method of claim 1 , wherein determining the pressure gradient required to extract the fluid comprises using a calibration factor to compensate for resistance of fluid flow caused by the microneedles.