Diagnostic Testing Flashcards
Chest xray (CXR)
Standard for looking at anatomy of chest
Most common views = PA, Lateral
Static view
Should be able to see all 12 ribs
Purpose - looking for abnormalities, tracking progress
Mediastinum
A little wider than thoracic spine, where the heart is
Super wide could indicate aneurism
Alveolar pattern
Look fluffy with present changes in distal airways
Pulm edema or pneumonia is more fluffy in appearance
Bones and soft tissue CXR
Size, shape, symmetry
Width of IC spacing
Hemidiaphragms CXR
R v L differences
Costophrenic angle
Angle
Symmetry
Lat 10th rib to xypho-sternum
***Changes throughout breathing cycle
Mediastinum and Hila CXR
Width
Vasculature
Masses
Lung fields CXR
Density
Alveolar patterns
Interstitium
Pleura CXR
Should not normally be able to see
Heart CXR
Shape
Position
COPD or emphysema CXR
Widened IC spaces
Flattened hemi-diaphragms
Squared-off costophrenic angles
Rib angles approaching 90-degrees
CT scans
With contrast…
Done to show tissues with increased density proportionally to their vascularity
Used to look for pulmonary nodules
MRI
Magnetic field and radio waves to get the images
Looks at concentration of protons
Good for soft tissue or lymph nodes
Costly, but better to see soft tissue compared to CT scans
Pulmonary angiogram
Xrays to see where dye is going
Catheter through a vein moving towards heart chambers where dye is injected
You can see blockages
Bronchoscopy
Direct visualization of the bronchial trees through a scope
Infections
Malignancy
Biopsy
Clear secretions
V/Q scan
Inhale radioisotope
Inject radioisotope
Examine by xray… how areas of lung are being ventilated and perfused
Poor ventilation
May be airway obstruction
Poor perfusion
May be pulmonary embolism
Cytology
Looking at cells from area of body under a microscope
Can be done to determine what cells look like and to see infections
Hematology
WBC, RBC, platelets, Hb, Hematocrit
PTT - Partial Thromboplastin time (reflective of Heparin)
PT - Prothrombin time
INR - International Normalized Ratio
Low PCO2
Alveolar HYPERventilation
High PCO2
Alveolar HYPOventilation
PCO2 > 50
Respiratory failure
Extent of failure is determined by accompanying change in pH
More stable pH in CHRONIC condition
Kidneys hold onto bicarbonate to balance the body environment
Failure of pulmonary system to meet metabolic demands of the body
Combined metabolic and respiratory?
Metabolic can be combined
You can have both metabolic and respiratory situation
CANNOT have combined respiratory
Primary respiratory acute v chronic
If HCO3- is normal, there is NO compensation and is probably more acute
If HCO3- is abnormal, there IS compensation and is probably chronic
Can also look at difference between PCO2 and pH
Acute = change of 10 accompanied by 0.08 pH shift
Chronic = change of 10 accompanied by 0.03 pH shift
Base excess
Provides information about the non-respiratory component of pH
Determined by comparison of expected pH to reported pH
So if it is balanced and health, BE is 0
If acidotic…
Any aerobic activity will further lower the pH
Xray shades
Dark - rays go through body without being absorbed
Lighter - more rays are absorbed
Air - Dark, radioluscent
Fat - Dark gray
Muscle/other tissue - Lighter gray
Bone - White, radio opaque
