<p> Highlights of the 02 analyzer Reading assignments: Cairo’s pp. 234-240 Egan’s pp. i. The function of a 02 analyzer: to monitor the Fi02 of a 02 device. During mechanical ventilation of the adult this needs to be done 1-2x a day or with changes, in neonatal application 02 must be analyzed constantly and recorded with all charting. ii. Calibration of all analyzers </p><p> a. 02 analyzers require a Q 8-12 hour 2-point calibration </p><p> b. 02 analyzers are accurate +/- 2 % </p><p> c. Calibrate to room air [20.9%] then calibrate to 100%</p><p>We can hold the 02 probe to the room to get 21%, but high calibration involves placing the probe into a plastic bag filled with pure 02 and waiting till the analyzer stabilizes. If the high Fi02 is less than 98% or more than 101%, turn calibration control to 100%. iii. Types of 02 analyzers a. Galvanic cell 02 analyzer or polar graphic electrochemical principal i. As 02 molecules enter the chamber, 02 combines with water and electrons from the negative electrode [cathode] form Hydroxyl ions [OH-] </p><p> ii. These OH- migrates to the anode [positive electrode] </p><p> iii. The free electrode move through a current meter which measures the electrical current iv. Current of electricity is proportional to the P02 </p><p> v. Measures the P02 but display is in Fi02 </p><p> vi. While this is a fast 02 monitor the chemical is used up constantly. Keep it turned off when you aren’t using it. </p><p> vii. Is responsive to changes in PIP, PEEP and humidity </p><p> viii. Hudson, Miniox, Teledyne and Ohmeda are all brands of galvanic cell b. Paramagnetic 02 analyzer [no longer used] i. Pauling principle: 02 is attracted to a magnetic field and will line up north to south in a magnetic field more than N2 does </p><p> ii. This analyzer has a glass dumbbell filled with N2 suspended from a fine quartz line. </p><p> iii. The dumbbell is suspended over magnets </p><p> iv. As 02 enter the chamber, the dumbbell rotates as the 02 changes the magnetic field. </p><p> v. The dumbbell reflects a light onto scale to read the 02 </p><p> vi. Needs calibration for a new altitude & the gas must be dried with a chemical such as silica gel. </p><p> vii. It will not read moving gas </p><p> viii. Examples are the Beckman c. Wheatstone bridge: thermo-conductivity i. 02 cools off wire, because 02 has a larger mass than Nitrogen </p><p> ii. The current changes as the wire surrounded by 02 cools </p><p> iii. There are 4 resistors </p><p>1. Two in the sample chamber [02 enters here] </p><p>2. Two in the reference chamber [Nitrogen]</p><p> iv. As Fi02 varies the resistance changes </p><p> v. The differences between the sample chamber and the reference chambers’ resistances are recorded as Fi02 </p><p> vi. Examples are MIRA and OEM d. Polargraphic: Clark electrode i. Chemical reaction results in electron flow which is measured, very similar to the galvanic analyzer but this one generates electrons with a battery rather than the chemical</p><p> ii. Measures P02 not Fi02 iii. Responsive to changes in PIP and PEEP iv. Example is the Ohio</p>