Respiratory Reference
Oxygen Delivery Devices
| Device | Flow Rate (L/min) | FiO2 (%) |
|---|---|---|
| Nasal Cannula | 1–6 | 24–44 |
| Simple Mask | 5–8 | 40–60 |
| Venturi Mask | 4–12 | 24–50 |
| Non-Rebreather | 10–15 | 80–95 |
| High-Flow Nasal Cannula | Up to 60 | Variable |
| CPAP | — | Variable |
| BiPAP | — | Variable |
Normal Respiratory Values
| Parameter | Normal |
|---|---|
| Tidal Volume | 500 mL |
| Minute Ventilation | 6–8 L/min |
| Vital Capacity | ~4–5 L (adult) |
| FRC (Functional Residual Capacity) | ~2.5 L |
| Dead Space | ~150 mL |
| RR (Respiratory Rate) | 12–20 breaths/min |
Breath Sounds
| Sound | Location | Description | Associated With |
|---|---|---|---|
| Vesicular | Peripheral lung fields | Soft, low-pitched; inspiration > expiration | Normal |
| Bronchovesicular | Between scapulae, sternum | Medium pitch; equal inspiration/expiration | Normal |
| Bronchial | Over trachea | Loud, high-pitched; expiration > inspiration | Consolidation if over lung |
| Crackles (fine) | Bases | High-pitched; popping; end inspiration | Pulmonary edema, fibrosis |
| Crackles (coarse) | Bases | Low-pitched; bubbling | Secretions, pneumonia |
| Wheezes | Diffuse or localized | High-pitched; musical; expiration | Asthma, bronchospasm |
| Rhonchi | Large airways | Low-pitched; snoring; may clear with cough | Secretions |
| Stridor | Upper airway | High-pitched; inspiration | Airway obstruction |
| Pleural friction rub | Lateral chest | Grating; inspiration and expiration | Pleuritis |
Ventilator Settings
| Mode | Description |
|---|---|
| AC (Assist-Control) | Machine delivers set volume/rate; patient can trigger additional breaths |
| SIMV | Synchronized intermittent mandatory ventilation; allows spontaneous breaths between mandatory |
| PSV | Pressure support ventilation; patient triggers; machine assists with pressure |
| CPAP | Continuous positive airway pressure; spontaneous breathing with constant pressure |
| PEEP | Positive end-expiratory pressure; maintains alveolar recruitment |
Key parameters: FiO2, Tidal Volume, Rate, PEEP, I:E ratio
Chest Tubes
Placement: Pleural space (for pneumothorax, hemothorax, pleural effusion)
Drainage types: Serous (clear, pale yellow), Sanguineous (bloody), Serosanguineous (pink-tinged)
Troubleshooting: Air leak (check connections, bubbling in water seal); Dependent loops (keep tubing above chest level); Clamping (avoid unless ordered; risk of tension pneumothorax)
Expected drainage: 100–200 mL/hr first few hours post-op; decreasing over 24–48 hours; notify if >200 mL/hr or sudden increase
Suctioning
| Type | Catheter Size | Duration | Key Points |
|---|---|---|---|
| Oropharyngeal | Yankauer (rigid) | As needed | Mouth only; avoid gag reflex; no suction during insertion |
| Nasopharyngeal | 12–18 Fr (adult) | 10–15 seconds | Lubricate; measure ear to nose; intermittent suction |
| Endotracheal | ½ inner diameter of ETT | 10–15 seconds max | Pre-oxygenate; sterile; no suction during insertion; limit passes |