1. CPAP Respiratory therapy EMT-B

2. CPAP Overview  Applies continuous pressure to airways to improve oxygenation.  Bridge device to improve oxygenation until underlying cause of the respiratory distress can be treated.

3. Primary Goal of CPAP  The primary goal of CPAP is to decrease the work of breathing so the patient doesn’t deteriorate, doesn’t require intubation—which is associated with increased mortality—and doesn’t suffer respiratory arrest.

4. C-PAP vs. PEEP  C-PAP non-invasive  ? PEEP for intubated patients  ? Terms used interchangeably

5. Control of Breathing  CO2 Level in Arterial Blood  ? Hypoxic Drive

6. Gas Exchange  Ventilation-allow oxygen to move from the air into the venous blood and carbon dioxide to move out.  Diffusion-Blood carries oxygen, carbon dioxide, and hydrogen ions between tissues and the lungs. The majority of CO 2 transported in the blood is dissolved in plasma  Perfusion-blood flow through the pulmonary arterioles.

7. Ventilation

8. Diffusion

9. Perfusion

10. Congestive Heart Failure  The primary cause of respiratory distress with heart failure is increased work of breathing. In heart failure, the heart cannot efficiently pump the blood delivered to it.

11. Congestive Heart Failure  The role of CPAP in the treatment of heart failure is twofold  1. The PEEP helps keep the alveoli open during exhalation, and inspiratory pressure helps to open additional alveoli, relieving the work of breathing; 2. The pressure generated by CPAP helps move fluid back into the vascular system.

12. Congestive Heart Failure  Pulmonary edema washes out surfactant  – Increased work of breathing to maintain open alveoli

13. COPD  Chronic Obstructive Pulmonary Disease  – Emphysema  – Chronic Bronchitis  – Asthma

14. Emphysema  Loss of elasticity of lung tissue  – Difficulty exhaling  Air trapping  CO2 retention  ? Break down of  alveolar walls  – Decrease surface area for gas exchange

16. Chronic Bronchitis  Chronic Inflammation of bronchiole tree with increased mucous production  ? Difficulty exhaling  – Air trapping  – CO2 retention

17. Asthma  Intermittent Bronchoconstriction Difficulty exhaling  – Air trapping  – CO2 retention

18. Physiological Benefits of C-PAP  Increase in alveolar pressure  – Stop fluid movement into alveoli  – Improves gas distribution  – Prevents alveolar collapse  – Improves re-expansion of alveoli  Reduces work of breathing  Reduces respiratory muscle fatigue

19. Physiological Benefits of C-PAP  Increases intrathoracic pressure  – Improves cardiac output to a point  – Too much PEEP decreases cardiac output  Decreases need for intubation and associated complications

20. Hazards/Complications of C-PAP  Airway  – Mask impairs access to patient’s airway  – C-PAP does not ventilate the patient  – Gastric distension / vomiting  Aerophagia (swallowing air) sensitive patients  – Gastric stapling  – Upper GI surgery

21. Hazards/Complications of C-PAP  Hypoxia  – Loss of oxygen supply  Empty oxygen tank  Disconnection of Oxy-PEEP from oxygen source  – Mask Leak  – Rebound hypoxia may be more severe  than initial hypoxia

22. Hazards/Complications of C-PAP  Hypotension  – Increased intrathoracic pressure causes  Decreased venous return  Decreased cardiac output  – Increased pulmonary pressure causes  Decreased blood flow through pulmonary vessels  Decreased cardiac output

23. Hazards/Complications of C-PAP  Patient Discomfort  – Requires patient cooperation to tolerate a  tightly fitting mask  Sensation of smothering or claustrophobia  – Use trial to introduce patient to device prior  to securing head strap  – Consider sedation for extreme anxiety with  orders from Medical Control

24. Procedure  Prepare Patient  – Position Stretcher at 45 degrees or higher  – Inform patient of procedure

25. Procedure  Mask Application  – Trial to introduce device  Explain patient will feel positive oxygen  pressure  – Hold mask gently on patient’s face  ensuring good seal  – Once patient accepts mask, secure mask  with straps  – Deflate mask as needed to get good seal

26. Procedure  On-Going Care / Monitoring  – Reassess at least every 5 minutes  Patient’s impression of difficulty breathing  Vital signs  Lung sounds  SpO2  – Observe for complications  Hypotension  Barotrauma  Worsening dyspnea

27. Procedure  If patient continues to have severe difficulty breathing after 5 minutes, consider increasing PEEP to 10 cm  H2O  – Systolic BP must be at least 90 mmHg  – CAREFULLY watch for complications of increased PEEP

28. Discontinuing C-PAP  C-PAP usually is not discontinued in the field High PEEP level may require weaning  Rebound hypoxia can be worse than initial hypoxia