From the FDA Drug Label
2 DOSAGE & ADMINISTRATION
The usual initial antihypertensive oral dose of Amlodipine besylate tablets is 5 mg once daily, and the maximum dose is 10 mg once daily. The antihypertensive of choice for a patient with a suspicion of pulmonary thromboembolism (PTE) post total knee replacement (TKR) is Amlodipine, with a recommended initial dose of 5 mg once daily.
- The dose may be adjusted according to blood pressure goals.
- In general, wait 7 to 14 days between titration steps.
- Titrate more rapidly, however, if clinically warranted, provided the patient is assessed frequently 1 1.
From the Research
For a post-total knee replacement (TKR) patient with suspected pulmonary thromboembolism (PTE) who requires antihypertensive therapy, calcium channel blockers, particularly amlodipine, would be the preferred choice. This recommendation is based on the need to manage blood pressure while considering the potential interactions with anticoagulants and the pathophysiology of PTE. The choice of antihypertensive is crucial in this context, as it needs to balance the control of blood pressure with the potential risks and benefits in the setting of PTE. Key considerations include:
- Avoiding medications that could worsen hypoxemia or mask symptoms of hemodynamic instability.
- Selecting medications that have a favorable interaction profile with anticoagulants.
- Considering the impact of the medication on pulmonary arterial pressure.
Given these considerations, calcium channel blockers like amlodipine are advantageous because they do not significantly interact with anticoagulants and can help reduce pulmonary arterial pressure, which is beneficial in patients with pulmonary embolism 2, 3. Start with amlodipine 5mg once daily, titrating up to 10mg if needed. It's also important to avoid beta-blockers as they may worsen hypoxemia by inhibiting compensatory tachycardia and could mask symptoms of hemodynamic instability in PTE. ACE inhibitors and ARBs are generally acceptable alternatives but monitor renal function closely, especially if the patient is on contrast for PTE diagnosis or has hemodynamic compromise 4. Diuretics should be used cautiously as dehydration could worsen the hypercoagulable state. Regular monitoring of blood pressure, renal function, and electrolytes is essential, particularly during the acute phase of PTE management 5.