What to do for a 90-year-old patient with a dry cough on perindopril (angiotensin-converting enzyme inhibitor) and atelectasis on chest X-ray (CXR)?

Management of Dry Cough in a 90-Year-Old Patient on Perindopril with Atelectasis

For a 90-year-old patient with dry cough on perindopril and atelectasis on chest X-ray, discontinue the ACE inhibitor and switch to an angiotensin receptor blocker (ARB) as the most effective treatment approach. 1, 2

ACE Inhibitor-Induced Cough

• Perindopril, like other ACE inhibitors, commonly causes a dry, persistent cough as a side effect in approximately 10-20% of patients 2
• The diagnosis of ACE inhibitor-induced cough is confirmed by resolution of the cough after discontinuation of the medication, typically within 1-4 weeks (though it may take up to 3 months in some cases) 1
• ACE inhibitor-induced cough is caused by the accumulation of bradykinin and substance P, which stimulates cough receptors 3
• The only uniformly effective treatment for ACE inhibitor-induced cough is discontinuation of the ACE inhibitor 1

Management Strategy

Primary Intervention

• Discontinue perindopril immediately regardless of the temporal relationship between the onset of cough and initiation of ACE inhibitor therapy 1
• Switch to an angiotensin receptor blocker (ARB) as the preferred alternative since ARBs have a similar mechanism of action but do not affect bradykinin metabolism 2, 3
• For a 90-year-old patient, start with a low-dose ARB such as losartan 25mg once daily or telmisartan 40mg once daily 2, 3
• Monitor blood pressure, renal function, and potassium levels within 1-2 weeks after switching medications 3

Addressing Atelectasis

• Atelectasis (collapsed and non-aerated region of lung parenchyma) may be exacerbated by the dry cough and requires separate management 4
• Examine for air-bronchograms on chest X-ray to determine whether proximal or distal airway obstruction is involved 5
• Consider chest physiotherapy and postural drainage to help clear secretions and re-expand collapsed lung tissue 4, 5
• If mucous plugging is suspected, bronchodilator therapy may be helpful 4
• For persistent atelectasis not responding to conservative measures, bronchoscopy may be necessary to remove mucous plugs 4, 5

Monitoring and Follow-up

• After switching from perindopril to an ARB, expect resolution of cough within 1-4 weeks 1, 2
• Pay particular attention to postural blood pressure changes in this elderly patient 3
• Monitor for adequate blood pressure control, as the goal should be appropriate for a 90-year-old patient 1
• If blood pressure control is inadequate on the initial ARB dose, the dose can be titrated upward (e.g., losartan to 50mg daily or telmisartan to 80mg daily) 2, 3
• Follow up with repeat chest imaging to assess resolution of atelectasis after cough improvement 5

Important Considerations for Elderly Patients

• Start with lower doses of ARBs in elderly patients and titrate slowly to avoid adverse effects 2
• Be vigilant for potential side effects of ARBs including hypotension, hyperkalemia, and worsening renal function 3
• Although rare, angioedema has been reported with ARBs in patients who previously experienced angioedema with ACE inhibitors 3
• If ARBs are not tolerated, consider a calcium channel blocker as an alternative antihypertensive medication 2

By discontinuing perindopril and switching to an appropriate ARB, the patient's dry cough should resolve, which will also help improve the atelectasis by eliminating the persistent irritation to the airways.