Should a patient with normal blood pressure, being discharged after a total knee arthroplasty (TKA), continue taking their current antihypertensive medications, including Aldactazide (spironolactone), Amlodipine, and Valsartan, or should they be held and provided with blood pressure parameters for monitoring?

Post-TKA Discharge: Continue Antihypertensive Medications

Continue all three antihypertensive medications (Aldactazide, amlodipine, and valsartan) at discharge without holding them, as the current blood pressure of 111/66 mmHg is acceptable and does not warrant medication discontinuation in a post-surgical patient. 1

Rationale for Continuing Medications

In patients with compensated cardiovascular status undergoing non-cardiac surgery, it is reasonable to continue guideline-directed medical therapy (GDMT) in the perioperative period unless contraindicated, to reduce the risk of worsening heart failure or hypertensive rebound. 1

• The 2024 AHA/ACC perioperative guidelines specifically recommend continuing antihypertensive medications postoperatively, as delaying resumption of preoperative ACE inhibitors/ARBs has been associated with increased 30-day mortality risk in propensity-matched cohort studies. 1

• Chronically taken oral antihypertensive medications should be restarted as soon as clinically reasonable to avoid complications from postoperative hypertension, including myocardial ischemia, acute decompensated heart failure, cerebral ischemia, and dysrhythmias. 1

• A blood pressure of 111/66 mmHg is not considered hypotensive in the postoperative setting—the threshold for concern is typically a mean arterial pressure (MAP) <60-65 mmHg or systolic blood pressure <90 mmHg. 1

Why Not to Hold These Medications

• Oral GDMT should not be withheld for mild or transient reductions in blood pressure, as demonstrated in multiple heart failure trials where patients with systolic blood pressure <110 mmHg still tolerated and benefited from continued therapy. 1

• In the PARADIGM-HF trial, patients with lower systolic blood pressure on sacubitril-valsartan had the same tolerance and relative benefit compared with patients with higher blood pressure. 1

• Discontinuation of ACE inhibitors/ARBs among hospitalized patients has been associated with higher rates of post-discharge mortality and readmission in the Get With The Guidelines-Heart Failure registry. 1

• Continuation of spironolactone (the active component in Aldactazide) among hospitalized patients was associated with lower 30-day mortality and heart failure rehospitalization in the COACH study. 1

Blood Pressure Parameters for Monitoring

Rather than holding medications, provide blood pressure parameters for nursing staff to monitor and contact you if:

• Systolic blood pressure drops below 90 mmHg 1
• Mean arterial pressure falls below 60-65 mmHg 1
• Patient develops symptomatic hypotension (lightheadedness, dizziness, syncope) 2
• Patient shows signs of end-organ hypoperfusion (altered mental status, decreased urine output, cool extremities)

Specific Medication Considerations

Valsartan (ARB):

• The FDA label indicates that low blood pressure can occur, especially when starting treatment or in volume-depleted patients, but does not recommend routine discontinuation for asymptomatic mild hypotension. 2
• Monitor for symptomatic hypotension, particularly if the patient is volume-depleted from surgical fluid shifts or inadequate oral intake. 2

Amlodipine (Calcium Channel Blocker):

• Provides complementary vasodilation and has demonstrated cardiovascular protection when combined with ARBs. 3, 4
• The combination of amlodipine and valsartan is well-established for blood pressure control with favorable tolerability. 5, 6

Aldactazide (Spironolactone + Hydrochlorothiazide):

• Monitor serum potassium and renal function, as the combination of spironolactone with valsartan increases hyperkalemia risk. 2
• The diuretic component may require dose adjustment if the patient becomes volume-depleted, but should not be routinely held. 1

Critical Monitoring Points

• Check serum potassium and creatinine within 1-4 weeks post-discharge, as the combination of spironolactone and valsartan increases risk of hyperkalemia and acute kidney injury. 2

• Ensure adequate oral hydration before discharge, as volume depletion combined with these medications can precipitate symptomatic hypotension. 2

• Avoid NSAIDs for post-surgical pain control if possible, as they can attenuate the antihypertensive effect and worsen renal function when combined with ARBs and diuretics. 2

Common Pitfall to Avoid

Do not intensify antihypertensive therapy at hospital discharge based on a single elevated reading, as a nonrandomized propensity-matched cohort study showed this practice increased 30-day risk of readmission and serious complications in older adults with hypertension. 1