CXR interpretation, ECG basics, cardiac markers, and diagnostic procedures.
70 min estimated
Systematic CXR interpretation: use the mnemonic 'ABCDE' — Airways, Bones, Cardiac, Diaphragm/Drains/Devices, Everything else (lungs/pleura).
Key findings: - Consolidation: airspace opacity with air bronchograms → pneumonia, lung contusion, pulmonary edema - Atelectasis: volume loss, shift toward opacified area, elevated hemidiaphragm - Pneumothorax: visceral pleural line, absence of lung markings, mediastinal shift away (tension) - Pleural effusion: blunting of costophrenic angles, meniscus sign, >200 mL to see on PA CXR - Cardiomegaly: cardiothoracic ratio >0.5 on PA film - Pulmonary edema: bat-wing pattern, Kerley B lines, cephalization of vessels, increased cardiac silhouette
Clinical Tip
In tension pneumothorax, DO NOT wait for CXR if patient is hemodynamically compromised — decompress immediately with 14–16g needle in 2nd ICS midclavicular line.
RTs need to recognize life-threatening arrhythmias and common ECG findings in respiratory conditions.
Key arrhythmias: - V-fib: chaotic, no organized rhythm — defibrillate immediately - V-tach (pulseless): treat as V-fib; if pulse present, lidocaine/amiodarone - SVT: narrow complex, rate 150–250 — adenosine 6mg IV push - AV blocks: 3rd degree (complete) = atropine, pacing
Responsible conditions: - COPD: right axis deviation, P pulmonale, low voltage (hyperinflation) - PE: S1Q3T3, sinus tachycardia, right heart strain (RBBB, T-wave inversions V1–V4) - Hyperkalemia: peaked T waves, wide QRS, sine wave pattern — emergency - Hypoxia: tachycardia, ST changes, arrhythmias
Clinical Tip
In a vented patient with sudden bradycardia + hypoxia, assume the ET tube is in the wrong place until proven otherwise. Manually ventilate and reconfirm position.
Flexible bronchoscopy allows direct visualization of the airways to the level of subsegmental bronchi. Diagnostic indications: unexplained hemoptysis, unresolved infiltrate, suspected endobronchial lesion, airway foreign body, BAL for infection/malignancy workup.
BAL (bronchoalveolar lavage): instill and retrieve saline from distal airspace — sends for culture (>10⁴ CFU/mL diagnostic for pneumonia), cytology, cell count. Normal: >80% alveolar macrophages.
Therapeutic bronchoscopy: mucus plug removal (lobar atelectasis), foreign body retrieval, massive hemoptysis management (balloon tamponade, epinephrine), airway stenting.
Complications: hypoxemia, bronchospasm, laryngospasm, bleeding, pneumothorax, arrhythmias. Preoxygenate before procedure; monitor SpO2 continuously.
Clinical Tip
When using bronchoscopy for mucus plug in a vented patient, the scope diameter reduces effective ET tube diameter — ensure adequate ventilation around the scope.
CXR Interpretation in a Vented Patient
A vented patient suddenly deteriorates. CXR shows rightward tracheal deviation, absent left lung markings, and increased lucency on the left. SpO2 drops to 75% despite FiO2 1.0.
What does the CXR show and what is the immediate treatment?
Left tension pneumothorax. Immediate needle decompression: 14–16g needle into 2nd intercostal space, left midclavicular line, then chest tube.
Tracheal deviation AWAY from the affected side (right deviation = left-sided problem). Absent lung markings = no air in lung. This is a tension pneumothorax. Do not wait for additional imaging — needle decompress immediately, followed by chest tube insertion.
Arterial Blood Gas Interpretation
Master systematic ABG interpretation including primary disorders, compensation, and mixed disturbances.
Pulmonary Function Testing
Interpret spirometry, lung volumes, DLCO, and flow-volume loops with confidence.
Hemodynamic Monitoring
Understand pulmonary artery catheters, cardiac output, vascular resistance, and hemodynamic profiles.
Laboratory Values
CBC, BMP, CMP, coagulation studies, cultures, and critical lab values for respiratory care.