How should hypertension (HTN) be managed in an adult patient with acute kidney injury (AKI) and a history of chronic kidney disease (CKD)?

Hypertension Management in Acute Kidney Injury with Chronic Kidney Disease

In patients with AKI and underlying CKD, immediately discontinue ACE inhibitors, ARBs, NSAIDs, and diuretics, initiate volume resuscitation with isotonic crystalloids, and once euvolemic, target BP <130/80 mmHg using non-RAAS blocking agents such as dihydropyridine calcium channel blockers. 1

Immediate Medication Management

Stop all nephrotoxic and RAAS-blocking medications immediately:

• Discontinue ACE inhibitors and ARBs as they worsen AKI and cause hyperkalemia, particularly in volume-depleted states 1
• Stop all NSAIDs immediately—they increase AKI risk more than twofold in volume-depleted patients 1
• Withdraw all diuretics to prevent exacerbation of prerenal AKI 1
• Systematically reassess all medications for nephrotoxicity and renovascular effects, as drug clearance is altered by decreased glomerular and tubular function 2

Volume Resuscitation Strategy

Prioritize hemodynamic stabilization before BP control:

• Use isotonic crystalloids (normal saline or Ringer's lactate) as first-line therapy for volume expansion 1, 3
• Avoid starch-containing colloid solutions, which are associated with harm in AKI 1
• Aggressive fluid repletion in the early setting is beneficial, but monitor closely to avoid fluid overload which increases mortality and reduces kidney recovery 3
• Target mean arterial pressure >65 mmHg, though patients with preexisting hypertension may require higher perfusion pressure 4

Blood Pressure Targets During Acute Phase

Exercise caution with BP lowering during active AKI:

• The long-term goal of <130/80 mmHg for CKD patients should be approached cautiously during acute AKI 1
• Avoid aggressive BP reduction that could compromise renal perfusion—hypotension and hypovolemia worsen kidney injury 3
• Most patients who develop severe hypertension during hospitalization (SBP >180 or DBP >110 mmHg) may be harmed by IV antihypertensive treatment, with 18% developing AKI when treated versus 13% when not treated 5
• Any acute loss of kidney function during hospitalization independently increases mortality risk (odds ratio 1.05 per 10 mL/min decline in eGFR) 6

Antihypertensive Selection During AKI

Use agents that preserve renal perfusion:

• Dihydropyridine calcium channel blockers (amlodipine, nifedipine) are first-line agents for hypertensive patients with AKI 1
• Thiazide-like diuretics (chlorthalidone, indapamide) only after volume repletion is complete 1
• Avoid hydralazine in patients with advanced renal damage—it should be used with caution as it can affect renal function 7

Monitoring Parameters

Daily surveillance is essential:

• Monitor serum creatinine, electrolytes, urine output, and blood pressure daily 1
• Check basic metabolic profile within 2-4 weeks after any medication adjustments 2
• Assess for volume status, orthostatic hypotension, and symptoms of hypotension (fatigue, light-headedness) 2

Renal Replacement Therapy Indications

Initiate RRT when conservative management fails and any of the following develop:

• Severe oliguria/anuria
• Refractory hyperkalemia
• Severe metabolic acidosis
• Volume overload with pulmonary edema
• Uremic complications
• Stage 3 AKI (creatinine >3× baseline) failing to improve 1

Note that uncontrolled hypertension together with edema and pulmonary congestion are indications for dialysis initiation, though caution is needed to avoid hypotensive episodes during dialysis 8

Reintroduction of RAAS Blockade

Resume ACE inhibitor or ARB therapy for long-term management after AKI resolution if:

• Albuminuria ≥300 mg/day or ≥300 mg/g creatinine ratio is present
• CKD stage 3 or higher exists
• Diabetes with any degree of albuminuria is present 1

For patients with CKD and albuminuria ≥300 mg/d, ACE inhibitors are reasonable to slow kidney disease progression (Class IIa recommendation) 2

Long-Term Blood Pressure Management Post-AKI

Once AKI resolves and patient is euvolemic, target BP <130/80 mmHg:

• This target applies to all adults with hypertension and CKD (Class I recommendation, Level B evidence for SBP) 2
• For patients with albuminuria ≥30 mg/24 hours, some guidelines suggest targeting <120 mmHg using standardized office measurement 9
• For patients without albuminuria, maintain BP <140/90 mmHg 2, 9

Follow-Up Strategy

Structured monitoring prevents recurrent AKI:

• Monitor serum creatinine every 2-4 weeks for 6 months after discharge to detect recurrent AKI 1
• Evaluate kidney function at 3 months post-AKI to assess for resolution, new-onset CKD, or worsening of pre-existing CKD 1
• Once BP goal is achieved, laboratory monitoring and clinic follow-up should occur every 3-6 months 2

Common Pitfalls to Avoid

• Do not continue RAAS blockade during active AKI—the renoprotective benefits do not apply during acute injury and these agents worsen outcomes 1
• Do not aggressively lower BP before volume resuscitation—this compromises renal perfusion and worsens AKI 3, 4
• Do not assume all severe hypertension requires IV treatment—most patients may be harmed by aggressive IV antihypertensive therapy during hospitalization 5
• Do not use colloids for volume expansion—isotonic crystalloids are superior and safer 1, 3