Advanced Pulmonary Diagnostics - Blood Gas Analyzers, Co-Oximetry, CXR's

Each Hgb can hold how many O2 molecules?

4

What specifically makes up the Hbg molecule?

4 globin proteins and 1 heme group

In the standard PA x-ray, what proportion of the chest width should the heart shadow not exceed?

50%

What is the numerical isosebestic point?

548 nm

What is normal Oxyhemoglobin level?

94-100%

What does Hgb do?

Hgb is a protein molecule that carries O2 from the lungs to the tissues and CO2 rom the tissues back to the lungs; also carries CO and NO.

What is the CaO2 formula and normal value?

Hgb x 1.34 x SaO2 + PaO2 x .003 Normal = 20 vol%

Where is Hgb located?

In the red blood cells

_____ = 5-7 anterior ribs intersecting at the diaphragm in the mid-clavicular line.

Inspiration

Where does CO2 bind on Hgb?

CO2 binds on the globin protein chains.

In what disease process will the left and right hemidiaphragm often be flat instead of dome shaped?

COPD/emphysema

The most common reference half-cell for the pH system is the _____ _____.

Calomel cell

What is Hgb + CO2?

Carboxyhemoglobin

How does the PO2 (Clark) blood gas electrode measure oxygen?

Change in electrical current

What is the FIRST thing you should check on every x-ray?

Do I have the right patient?

When should the co-oximeter be calibrated?

Every 24 hours, when sample tubing is changed, when cuvette is disassembled or changed, or when suspicious readings

Normal predicted PaO2 depends on what 3 factors?

Fio2, age, barometric pressure

With ABG analysis, what is calculated?

HCO3

What is the most appropriate radiographic technique to confirm the presence of free pleural fluid?

Lateral decubitis projection

____ - ______ Chart - a chart illustrating the allowable limits of error in laboratory test performance, the limits being a defined deviation from the mean of a control serum - most commonly +2 standard deviations.

Levy-Jennings

______ = spinous process at midpoint between medial ends of the clavicle.

Rotation

What does RIP stand for regarding x-rays?

Rotation, Inspiration, Penetration

State Dalton's Law.

Total pressure in a gas mixture equals the sum of partial pressures that make up the mixture. The sum of the parts equals the whole of the pressures.

______ = 6 or more results are in an increasing or decreasing pattern.

Trends

A Clark (PO2) electrode reduces oxygen to OH- which allows us to measure oxygenation by?

consuming electrons and changing current

Trends can be caused by worn _______or ________ or reagents of electrodes.

equipment, contamination

What is the name of the hormone that triggers RBC production?

erythropoietin

What problem is indicated by rounding of the costophrenic angles seen on the PA or lateral chest x-ray?

excess pleural effusion

What is the production of RBC's called?

hematopoiesis or erythropoiesis

What causes a metabolic alkalosis?

hypokalemia, hypochloremia, NG suction, vommitting, diuretics, steroids

Functional hemoglobin refers to what variants?

oxyhemoglobin and reduced hemoglobin

A co-oximeter provides what data?

oxyhemoglobin, reduced hemoglobin, carboxyhemoglobin, total hemoglobin, percentage of all hemoglobins, and some calculate O2 content

When looking at a chest x-ray and you see a deep sulkus and a subclavian line, what would you suspect?

pneumothorax

Fractional hemoglobin refers to what variants?

reduced hemoglobin, oxyhemoglobin, methemoglobin, carboxyhemoglobin

What are the first 3 rules when looking at an x-ray?

right person, right date, right time

Concerning the carbonic acid equation, an addition of HCO3 would cause what?

shift to the left

What concept are co-oximeters based on?

spectrophotometry

How does the co-oximeter measure the amount of Hgb in sample of blood?

spectrophotometry; infrared and red lights

What causes a metabolic acidosis?

diarrhea, renal failure, ketoacidosis, lactic acidosis, toxins

Carboxyhemoglobin normal - non smokers = _______ - ______ Carboxyhemoglobin normal smokers = _______ - _______

1-10% 1-2%

Standard Deviations: 1. Allow ______ SD's for normal results 2. If > +/- 2 SD's is a ______ error 3. If < +/- 2 SD's is a _______ error 4. Run ______ quality controls for comparison

1. +/- 2 2. system 3. random 4. 10

Calibraton of ABG Analyzers: 1. Add ______ solution for pH system only 2. High and low _______ points are established 3. Calibration should be done every ______ minutes 4. Usually does ________

1. buffer 2. calibration 3. 30 4. automatically

Rank O2, CO2, CO according to Hgb Affinity.

1. CO - 210 x affinity of O2 2 CO2 - 20 times affinity of O2 3. O2

pH Electrode - Reference Electrode: 1. ______ cell made of ________ chloride paste 2. ______ cell made of ______/______ _______ cell.

1. Calomel, mercurous 2. Reference, silver/silver chloride

Quality Control: 1. Documented on the _____ - ______ chart to show deviations 2. Standard deviations show the difference in the _____ and how much that number ______ from the accepted number 3. Acceptable results are within _____SD's (standard deviations) 4. Controls to be done every ______ hours

1. Levy-Jennings 2. data, varies 3. 2 4. 24

Random Error: 1. _____ measurement out of range 2. Factors are sample _______, sample _______, and statistical _______ 3. Corrections are done by rerunning the _______ and repeating _______ on different instrument

1. One 2. contamination, mishandling, probability 3. control, analysis

Basic Components: 1. ______ interface 2. ______ chamber 3. ______ gas tanks 4. _______ containers 5. _______ container 6. ______

1. Operator 2. Measuring 3. Calibrating 4. Reagent 5. Waste 6. Results

Quality Control and Assurance Requirements - Assurance Requirements: 1. _______ = policies and procedures must be established and followed 2. _______ validation = new instruments must be tested for accuracy of measurement claims 3. _______ maintenance and function checks = check filters, membranes, buffers, etc.....for deterioration and expiration

1. Recordkeeping 2. Performance 3. Preventative

PCO2 - Severinghaus Electrode: PCO2 - Severinhaus Electrode: 1. Invented by John _______ in ______ 2. Is basically a ______ system that is modified to measure _______ 3. CO2 is proportional to ______

1. Severinghaus, 1958 2. pH, CO2 3. pH

What should an RT do if there are air bubbles in the ABG sample?

1. Tap or roll the sample gently to remove bubbles 2. Discard the sample and draw another one

pH Electrode or Sanz Electode: 1. _____ systems in one 2. ______ electrode 3. ______ electrode

1. Two 2. Reference 3. Measuring

Quality Control: 1. Documents the ______ of the blood gas 2. Random sampling of known ______ solutions and partial pressure of _______ gases 3. Determines ______ and _______ 4. _____ levels of mixtures assures testing done with wide range of variables

1. accuracy 2. buffer, dissolved 3. variations, errors 4. Three

Calibration of ABG Analyzers: 1. Assures clinical _______ 2. Compares the _______ devices with the known concentrations of _______; this is how we get _______ points 3. Uses gas mixture of _______, ______, and _______ 4. For pH system a _____ _____ is used

1. accuracy 2. measuring, gases; calibration 3. O2, CO2, N2 4. buffer solution

Determining Calibration Points with ABG Analyzers: 1. Must have _____ pressure 2. Subtract ______ ______ pressure 3. Gas mixtures of _____ O2, ______ CO2, and balance is _______. 4. Uses ______ law of partial pressures 5. Machine will calculate to _______ %.

1. barometric 2. water vapor 3. 5%, 20%, N2 4. Dalton's 5. +/- 5%

How the PCO2 - Severinghaus Electrode works: 1. Blood moves through a _____ _____ permeable membrane 2. _____ diffuse through this membrane into an ______ solution 3. Causes _______ ________ 4. What is the hydration reaction formula? 5. Carbon Dioxide + H2O = _______ ______ 6. Free _____ ions and _______ ions 7. The greater the _______, the more _______ ions are produced and the ______ the pH changes.

1. carbon dioxide 2. CO2 3. hydration reaction 4. CO2 + H2O = H2CO3 = H+HCO3 5. carbonic acid 6. H+, bicarb 7. PCO2, H+, greater

Calibration Errors: 1. Inaccurate gas _______ 2. Inaccurate ________ readings 3. Calibration gas flow too ____ or too ______ 4. ______buildup from insufficient cleaning 5. _______ buffers

1. concentrations 2. barometric 3. high, low 4. Protein 5. Contaminated

How the PO2 - Clark Electrode works: 1. Blood moves in to a ______ chamber 2. ______ diffuses through the permeable membrane 3. O2 diffuses until equilibrium between _______ and ______ solution 4. Oxygen drawn into the _______ 5. O2 combines with H2O and electrons to from ______ 6. Negative ions drawn into the ______ anode 7. They give up their _______ and become a measureable current 8. This current reflects the partial pressure of ______ in the blood.

1. cuvette 2. O2 3. plasma, electrolyte 4. cathode 5. OH- 6. positive 7. electrons 8. O2

PCO2 - Severinghaus Electrode: 1. Consists of two _______ cells 2. Made of ______/______ _______ 3. Has nylon spacer with ______ membrane that allows ______ buffer 4. The nylon space is permeable only to ______

1. half 2. silver/silver chloride 3. Teflon, bicarb 4. CO2

The pH (Sanz) electrode: 1. Measures _____ _____ concentration 2. Indirectly measures _____ ______ tension

1. hydrogen ion 2. carbon dioxide

What are the 3 separate electrodes?

1. pH - Sanz 2. PCO2 - Severinghaus 3. PO2 - Clark or Polargraphic

What sort of problems may occur with a portable AP chest x-ray?

1. patient not centered on the film 2. artificial shadows may be present on the film 3. poor radiographic exposure

PO2 - Clark Electrode: 1. AKA _________ electrode 2. Invented by _____ ______ in ______

1. polargraphic 2 Leland Clark, 1958

pH Electrode - Reference Electrode: 1. Provides constant _______ 2. Electromechanical reaction must be _______ 3. Electromechanical reaction must be _______ 4. The system must be _____

1. potential 2. reversible 3. reproducible 4. stable

How the pH - Sanz Electrode works: 1. Blood sample moves through _____ cell and around the _____ glass 2. pH glass is ______ to ______ ions 3. The changes on either side of the pH is measured on the _______ and the pH is determined

1. reference, pH 2. permeable, hydrogen 3. voltmeter

pH Electrode - Measuring Electrode: 1. Made of ______/______ _______ rod 2. Surrounded by solution with a constant pH of ______ 3. Enclosed in a ______ sensitive membrane

1. silver/silver chloride 2. 6.84 3. pH

PO2 - Clark Electrode: 1. Consists of a ______/______ ______ anode and a _______ cathode. 2. Tip covered with an ______ permeable polypropylene membrane

1. silver/silver chloride, platinum 2. oxygen

Temperature Control: 1. Temperature plays factor in gas _______ 2. Need to ______ for temperature 3. Remember _______ law? 4. Increased _______ will increase _______ 5. Decreased ______ will decrease _______

1. solubility 2. correct 3. Henry's 4. temperature, solubility 5. temperature, solubility

Normal Hgb males = _____ - ______ Normal Hgb females = _____ - _____

13-18 g/dl 12-16 g/dl

When does Fetal Hgb decline?

After 6 months of age. Fetal Hgb has a greater affinity for O2 than adult Hgb.

What does the acronym ABCDE stand for regarding x-rays?

Apices, Bones and soft tissue, Cardiac shadow, Diaphragm, Edge of image

Shifts and Trends are _______

BAD!!

______ error = TREND or abrupt SHIFT in data points outside statistical limits.

Bias

If there is mucus plugging, will you see an air bronchogram on an x-ray?

NO!

Where does O2 bind on Hbg?

O2 binds to the heme group and some is dissolved in the blood

What is Hgb combined with O2?

Oxyhemoglobin

What does the Severinghaus electrode measure?

PCO2

______ = spine visible behind the heart

Penetration

What is the isosebestic point?

Point that Hgb, HgbO2, COHgb absorb the same amount of light

What are the 2 names for carboxyhemoglobin?

Reduced hemoglobin or deoxyhemoglobin

Which blood gas analyzer uses a separate reference and measurement electrode?

Sanz (pH) electrode

_____ = when 6 or more data points suddenly move in a random pattern on same side of mean.

Shift

List common problems with a co-oximeter that can cause erroneous results?

air bubbles, high lipid content, IV dyes, incomplete hemolysis, blood clots, failure to program for FeHgb

What causes a respiratory acidosis?

airway obstruction, pulmonary edema, drug overdose, trauma

What causes a respiratory alkalosis?

anxiety, pain, head trauma, hypoxemia, acidosis

What findings on a chest x-ray film is most consistent with pulmonary edema seen with ARDS?

bilateral patchy infiltrates of edema

Where are the RBC's produced and what is their life span?

bone marrow, spleen, and liver and the life span is 120 days

On an x-ray what will show up as the most radiopaque?

bones