AND ANSWERS
Three main causes for Hypoxemia: Answers: Hypoventilation
Ventilation/perfusion (V/Q) mismatch
DO2/VO2 imbalance
Intrapulmonary shunt: Answers: V/Q mismatch
Excessive blood flow in relation to ventilation
Ventilation without perfusion (pulmonary embolism)
Examples of shunting: Answers: Asthma - small airways restricted
Pulmonary edema - alveoli filled with fluid
Atelectasis - alveolar collapse
Pulmonary embolus
Too much oxygen has a negative inotropic effect on the heart: T/F Answers: True
Delivery Methods of oxygen: Answers: Nasal Cannula 1-6 (21 to 46%)
Face Mask 5-10L (40-60%)
Partial re-breather mask 5-7 (35 - 75%)
Non-rebreather mask 5-10L (40-100%)
Asthma Characteristics: Answers: Airway hyperactivity
Inflammation
Bronchial constriction
Lots of resistance
Treatment for Asthma: Answers: 1st Line Therapy: Bronchodilators!!!
Beta 2 agonist
Albuterol - onset < 5mins
, Side effects of Albuterol: Answers: Tachycardia
Tremors (stimulates Beta 2 receptors)
Hyperglycemia
Hypokalemia
Other asthma treatments: Answers: Anticholinergic Agents:
Atrovent
Only in combination with Beta 2 agonist (like albuterol)
Corticosteroids: Answers: Corticosteroids:
Reduces secondary airway inflammation & edema
Prevents relapse
Neither PO or IV is superior benefit not seen until 12 hours after therapy started
Mechanical Ventilation settings for asthma: Answers: Lower ventilation rate (allows more time for
exhalation)
Prolonged expiratory pause
Decrease minute ventilation
Lower tidal volume
COPD: Answers: Umbrella term for emphysema & chronic bronchitis
Constant airflow obstruction
SOB
Cough/sputum
Diagnosis for COPD: Answers: Pulmonary Function Test - FEV/FVC <70%
Normal: 80%
COPD - Emphysema Answers: Air trapping with chronic hyperinflation of lungs
Prolonged expiration
Elevated CVP
Enlarged right heart
COPD Treatment: Answers: Bronchodilators - some thought there may be limited benefit
Short course of corticosteroids - 7 to 10days Prednisone