Pulmonary Diagnostic Procedures Flashcards
What are the 4 pulmonary diagnostic procedures?
- Chest imaging: radiographs, CT
- Bronchoscopy
- Blood Gas Analysis
- Ventilation/Perfusion Scan
What is the predominant diagnostic test to determine anatomic abnormalities and pathological processes in the chest
Chest Radiographs- provides a static view of the anatomy of the chest
-air: dark
-bone: white
Advantages to CT scan
-much more sensitive
-evaluates lungs, heart, mediastinum, pleura, chest, and abdomen
-localizes disease
-guidance of interventional procedures
-evaluates chest tube placement
Disadvantages of CT scan
-risk of transporting patient out of ICU
-significantly increased radiation
-risk of intravenous contrast
What test involves a narrow beam of x-rays moving across field of examination?
CT scan- primarily used for diagnosis of tumors vs calcifications or nodules
What are you able to visualize on a chest x-ray?
-bones and soft tissue
-mediastinum and trachea
-hilum (roots of pulmonary blood vessels and bronchi)
-lung fields
-silhouette sign
-specific lung lesions (abnormal density)
What is a bronchoscopy?
Flexible, fiber optic tube that is inserted through the mouth or nose for direct visualization of the airways
-it allows direct access of previously inaccessible areas within the tracheobronchial tree
Indications for a bronchoscopy
-tissue biopsy
-secretion sampling and removal
-bronchial lavage for tissue identification
Arterial blood gas analysis provides information of which levels in the blood?
-pH
-oxygen concentration
-carbon dioxide concentration
-bicarbonate
Blood ph levels
-Normal: 7.35-7.45
-Acidosis: <7.35
-Alkalosis: >7.45
Normal partial pressure of oxygen within arterial blood
The amount of oxygen that is bound of hemoglobin
-normal: 80-100 mmHg
-abnormal: < 80 mmHg
What is SpO2?
Peripheral oxygen saturation that may be measured by a pulse ox
-normal: >95-90%
Hypoxemia levels PaO2
-mild: 60-80 mmHg
-moderate: 40-60 mmHg
-severe: <40 mmHg
What does the partial pressure of carbon dioxide tell us?
The adequacy of alveolar ventilation
-normal: 35-45 mmHg
-abnormal: < 35 mmHg (hyperventilating), > 45 mmHg (hypo-ventilating)
*for every 10 mmHg increase in PaCO2, the pH should fall 0.7 units
Normal Bicarbonate (HCO3) levels
Normal: 22-26 mEq/L
-determines if the pt has an acid balance imbalance
Which two ways can Acidosis occur?
- low HCO3 produces metabolic acidosis
- high PaCO2 produces respiratory acidosis
Which two ways can Alkalosis occur?
- high HCO3 produces metabolic alkalosis
- low PaCO2 produces respiratory alkalosis
What compensation occurs with Respiratory acidosis?
The kidneys retain bicarbonate in an effort to increase the pH
What is the compensation that occurs with respiratory alkalosis?
the kidneys excrete more bicarbonate to try and decrease the pH
What is the compensation that occurs with metabolic acidosis?
Decrease carbon dioxide levels by hyperventilating (blowing off the excess CO2 to being pH back to normal)
What is the compensation that occurs with metabolic alkalosis?
Increase carbon dioxide by hypo-ventilation to bring pH back to normal
T/F there is a normal inverse relationship between pH and CO2
True
-if the relationship is maintained: the problem is respiratory in nature
-if the relationship is not maintained: the problem is metabolic in nature
How to determine the adequacy of alveolar ventilation?
Look at PaCO2!
<30 mmHg: alveolar hyperventilation
30-50 mmHg: adequate ventilation
>50 mmHg: ventilatory failure
Patient X presents with:
PH 7.14
PaCO2 72 mmHg
HCO3 23mEq/L
What can you say about the acid base balance of this patient?
Does the patient have respiratory or metabolic imbalance
pH: acidotic
PaCO2: very high
Respiratory Acidosis
Patient S has the following ABG values:
pH 7.0
PaCO2 = 75 mmHg
HCO3 = 22 mEq/L
Does the patient have respiratory or metabolic imbalance
pH: acidotic
PaCO2: very high
Respiratory acidosis
Patient PT has the following ABG values:
pH 7.54
PaCO2 = 30 mmHg
HCO3 = 39 mEq/L
Does the patient have respiratory or metabolic imbalance
pH: alkalotic
PaCO2: low
Respiratory Alkalosis? …. but why? lol
What is a pulmonary ventilation/perfusion (V/Q) scan?
Uses inhaled and injected radioactive material to measure ventilation and perfusion in all areas of the lungs
-done by scanning the pts lungs while the person inhales radioactive gas
-2 tests that can be performed separately or together
Results of a V/Q scan
-decreased uptake of radioisotope during a perfusion scan indicates a problem with blood flow
-decreases uptake of radioisotope during a ventilation scan may indicate reduced breathing and ventilation ability or airway obstruction
