CLINICAL GAS ANALYZER

A NEED EXISTS TO DEVELOP A SMALLER, LIGHTER, MORE EFFICIENT, AND MORE RELIABLE CLINICAL GAS ANALYZER FOR RESPIRATORY AND ANESTHETIC GAS MONITORING. EXISTING LASER RAMAN-BASED INSTRUMENTATION USES A LARGE, HEAVY, AND EXTREMELY INEFFICIENT (0.1 PERCENT) ARGON ION LASER WITH AN INTRACAVITY GAS CELL THAT IS SUBJECT TO CONTAMINATION AND MISALIGNMENT. THE LONG-TERM OBJECTIVE OF THIS RESEARCH IS TO IMPLEMENT A SOLID-STATE LASER ALTERNATIVE TO THE EXISTING LASER AND AN EXTERNAL CAVITY GAS CELL THAT IS MUCH LESS SUSCEPTIBLE TO CONTAMINATION. SUCH A LASER IS SMALLER, LIGHTER, MUCH MORE EFFICIENT, AND HAS A LIFETIME GREATLY EXCEEDING THAT OF THE PRESENT LASER. THE SPECIFIC AIMS ARE TO: (1) BUILD A SINGLE-CHANNEL PROTOTYPE UTILIZING THE SOLID-STATE LASER, AN EXTRACAVITY GAS CELL, SELECTED SPECIFIC DIELECTRIC INTERFERENCE FILTERS FOR REJECTION OF THE ELASTIC SCATTERED LASER LIGHT AND TRANSMISSION OF GAS-SPECIFIC RAMAN LINES, AND SOLID-STATE PHOTODETECTORS; (2) EVALUATE THE PROTOTYPE FOR ACCURACY, LINEARITY, SENSITIVITY, PRECISION, STABILITY, AND INTERFERENCE BETWEEN VARIOUS ANESTHETIC AND RESPIRATORY GASES; (3) COMPARE THE MAXIMUM SIGNALS FOR PURE GASES TO THOSE CALCULATED ON THE BASIS OF A SYSTEM-MODELING EQUATION.