What is the next step for a patient with chest pain radiating to the right arm, hypoxemia (SpO2 88%), tachycardia (heart rate 102 bpm), and hypertension (BP 150/100)?

Emergency Management of Chest Pain with Hypoxemia, Tachycardia, and Hypertension

The immediate next step for this 65-year-old male patient with chest pain radiating to the right arm, hypoxemia (SpO2 88%), tachycardia (heart rate 102 bpm), and hypertension (BP 150/100) is to administer supplemental oxygen, obtain a 12-lead ECG within 10 minutes, establish IV access, administer aspirin, and provide pain relief while simultaneously monitoring vital signs.

Initial Assessment and Stabilization

• Administer supplemental oxygen immediately to correct hypoxemia (SpO2 88%), as oxygen therapy is indicated for patients with oxygen saturation below 90% 1, 2
• Obtain a 12-lead ECG within 10 minutes of first medical contact to determine if ST-segment elevation is present, which would indicate potential STEMI requiring immediate reperfusion therapy 1, 2
• Establish IV access and draw blood for cardiac biomarkers (troponin), complete blood count, and basic chemistry 2, 3
• Administer aspirin 160-325 mg orally if not contraindicated (no history of allergy or recent bleeding) 2, 3
• Place on continuous cardiac monitoring to detect arrhythmias and dynamic ischemic changes 1, 2

Pain Management and Initial Pharmacotherapy

• Administer sublingual nitroglycerin for pain relief, but use with caution due to tachycardia (102 bpm) which increases the risk of hypotension (monitor blood pressure closely) 4, 5
• Provide adequate analgesia with morphine sulfate if pain persists despite nitroglycerin 2, 3
• Consider beta-blockers (such as metoprolol) to address both tachycardia and hypertension if no contraindications exist 2, 3

Management Based on ECG Findings

If ST-segment elevation is present:

• Activate immediate reperfusion therapy protocol (primary PCI preferred if available within 120 minutes, otherwise thrombolysis) 1, 2
• Continue aspirin therapy and add additional antiplatelet agents as per STEMI protocol 1, 2
• Transfer directly to catheterization laboratory, bypassing emergency department if possible 1

If no ST-segment elevation:

• Continue aspirin therapy 1, 2
• Administer low molecular weight heparin or unfractionated heparin 1, 2
• Plan for early invasive strategy with coronary angiography if high-risk features are present 2, 3

Differential Diagnosis Considerations

• Acute coronary syndrome is the most likely diagnosis given the presentation of chest pain radiating to the arm with tachycardia and hypertension 1
• Consider aortic dissection, especially with chest pain described as "ripping" or "tearing" with hypertension 1
• Pulmonary embolism should be considered with hypoxemia and tachycardia 1
• Acute heart failure with pulmonary edema can present with hypoxemia, tachycardia, and hypertension 1

Admission and Monitoring

• Admit to a specialized coronary care unit or intensive care unit without delay 1
• Priority for CCU admission should be given to patients with severe continuing pain, ischemic ECG changes, positive troponin test, or hemodynamic abnormalities 1
• Monitor for recurrence of chest pain with repeat ECG if symptoms return 2, 3
• Obtain serial cardiac biomarkers (troponin) at 6-12 hours after initial presentation 2, 3

Important Pitfalls to Avoid

• Do not delay obtaining an ECG - it should be completed within 10 minutes of arrival 1, 2
• Do not administer nitroglycerin if systolic blood pressure is <90 mmHg or if there is severe tachycardia, as it may precipitate hypotension 4, 5
• Do not rely solely on pain severity to determine urgency, as severity is a poor predictor of imminent complications 3, 6
• Do not miss considering aortic dissection, which can present similarly to acute coronary syndrome, especially in hypertensive patients 1
• Be aware that hypoxemia with chest pain may indicate significant cardiac or pulmonary pathology requiring immediate intervention 7, 8