From the Guidelines
For a patient with impaired kidney function (eGFR 38, creatinine 1.35) and elevated blood pressure (178/64), I recommend starting with an Angiotensin II Receptor Blocker (ARB) as the first-line antihypertensive medication, given its benefits in patients with chronic renal disease and potential to reduce morbidity and mortality 1. The patient's presentation with a cough and impaired renal function requires careful consideration of potential medication interactions and side effects.
- The use of ARBs is supported by the 2016 ACC/AHA/HFSA focused update on new pharmacological therapy for heart failure, which recommends the use of ARBs to reduce morbidity and mortality in patients with prior or current symptoms of chronic HFrEF who are intolerant to ACE inhibitors due to cough or angioedema 1.
- The British Hypertension Society guidelines for hypertension management also suggest that ARBs may be beneficial in chronic renal failure, but should be used with caution and close supervision in patients with established and significant renal impairment 1.
- When initiating ARB therapy, it is essential to check renal function and electrolytes, start with a low dose, and titrate upward as needed, while monitoring for potential side effects such as hypotension and renal insufficiency 1.
- The patient's cough may be related to an ACE inhibitor medication, if they are taking one for blood pressure, and further evaluation is needed if the cough persists or worsens.
- Ensuring adequate hydration is crucial, unless fluid restriction has been recommended for their kidney condition.
- For the cough, guaifenesin (Mucinex) 400-600 mg every 12 hours or dextromethorphan (Robitussin DM) 10-20 mg every 4 hours can be considered as first-line options, as they are generally safe with moderate kidney impairment 1.
From the Research
Patient Presentation
The patient presents with a cough, impaired renal function (eGFR 38), high blood pressure (178/64 mmHg), elevated blood urea nitrogen (BUN) of 24, creatinine level of 1.35, and low carbon dioxide (CO2) level of 19.
Medication Considerations
- The patient's renal insufficiency requires careful consideration of medication dosages and potential interactions 2.
- Angiotensin-converting enzyme (ACE) inhibitors may be beneficial for patients with renal insufficiency, but they can cause cough, which is present in this patient 2, 3, 4.
- Alternative options, such as angiotensin II receptor blockers (ARBs), may be preferred due to their similar renoprotective effects and lower incidence of cough 5, 4.
- Calcium channel blockers may also be beneficial, especially when combined with ARBs, due to their potential renoprotective effects and ability to reduce the incidence of cough 5, 6, 3.
- Diuretics, such as thiazide or loop diuretics, may be necessary to manage volume expansion and hypertension, but require careful dosing to avoid hypovolemia, hyponatremia, and hypokalemia 2, 6.
Potential Treatment Options
- ARB-based combination therapy, such as telmisartan with hydrochlorothiazide or amlodipine, may be a suitable option for this patient 5.
- Calcium channel blockers, such as amlodipine, may be used in combination with ARBs or as an alternative to ACE inhibitors 5, 6, 3.
- Close monitoring of the patient's renal function, blood pressure, and electrolyte levels is necessary to adjust medication dosages and minimize potential adverse effects 2, 6.