Blood Gas Analysis and Analyzer(BME Lab 2) Palestine Polytechnic UniversityEngineering & Technology CollageElectrical &Computer DepartmentBiomedical Engineering ProgramBiomedical Eng Lab (II)
Blood Gas Analysis Blood gas analysis evaluates; how effectively the lungs are delivering oxygen to the blood and how efficiently they are eliminating carbon dioxide from it. how well the lungs and kidneys are interacting to maintain normal blood pH (acid-base balance).
Blood Gas Analysis Blood Gas Analyzer Measure the following Parameter pH Acid Degree PO2 Partial pressure of oxygen in blood PCO2 Partial pressure of carbon dioxide in blood cK Potassium Concentration NaSodium Concentration Glu Glucose Ct Bil Total Bilirubin
CO2 + H2O H2CO3 H+ + HCO3- pH Henderson-Hasselbalch Equation [H2O + CO2] [t x PCO2] [HCO3-] [H2CO3] pH = pKa + log [HCO3-] [0.03 x PCO2] pH = 6.1 + log 24 1.2 pH = 6.1 + log 1.3 20 1 pH = 6.1 + log pH = 7.4
pH PH value for Human Blood
PO2 PH value for Human Blood
pH • pH electrode is constructed of two half cells, which develop an electrical potential when connected together • Reference electrode maintains a constant potential and is bathed in KCl • Glass electrode (Sanz electrode) develops an electrical potential that is proportional to the amount of H+ present
Blood Gas Analyzer High O2 Low CO2 Microprocessor Calibrator Gas Low O2 High CO2 Display/Printer Water bath 37oC Standard Buffers High pH pH PO2 Low pH E1 E3 Pump Chamber V E4 E2 Sample Probe w PCO2 Reference for pH
A - pH sensor B - reference half-cell C - combination pH electrode (A + B) d - seal e - internal filling solution f - internal reference electrode g - external filling solution h - pH-sensitive glass membrane i - internal liquid junction j - external liquid junction k - fill hole Glass pH electrode
Blood Gas Analyzer BGA, BGE, BGA plus E Oximeter Tonometer Ion selective electrodes (ISE)
Oximeter CO-Oximeter % Carboxyhemoglobin % Oxyhemoglobin
A new dimension in non-invasive patient monitoring Continuous real-time CO2 partial pressure measurement combined with state-of-the-art pulse oximetry in a single non-invasive digital sensor.
Common Problems with Blood gas /PH analyzers includes 1-Out-of-date buffer solutions. 2-No calibration gas . 3-Poor Flushing . 4-Not taking the time to properly warm up the analyzer. 5- Bad electrode .