What is the best treatment approach for a patient with severe Pulmonary Arterial Hypertension (PAH) who is desaturating, at risk of requiring intubation, and has worsening Acute Kidney Injury (AKI) due to over-diuresis?

Management of Severe Pulmonary Arterial Hypertension in Acute Decompensation with AKI

For a patient with severe PAH who is desaturating, at risk of requiring intubation, and has worsening AKI due to over-diuresis, continuous IV epoprostenol is the most appropriate immediate treatment. 1

Initial Assessment and Stabilization

• Oxygenation: Maintain oxygen saturation >90% at all times 1

  • Continue BiPAP support to avoid intubation
  • Supplemental oxygen as needed

• Volume Status: Carefully manage fluid balance considering competing priorities:

  • AKI from over-diuresis requires judicious fluid administration
  • Avoid excessive fluid which could worsen right heart failure
  • Consider invasive hemodynamic monitoring to guide management

Specific PAH Treatment

First-line Therapy:

• IV Epoprostenol (continuous infusion):
  • Start at low dose and titrate gradually based on clinical response
  • Epoprostenol has demonstrated survival benefit in severe PAH 1
  • Provides rapid pulmonary vasodilation, improving oxygenation and right heart function
  • Only therapy for PAH proven to prolong survival in randomized controlled trials 1

Rationale for Epoprostenol:

1. Severity of presentation (desaturation, BiPAP requirement, impending respiratory failure)
2. Demonstrated mortality benefit in severe PAH (WHO Class III/IV)
3. Rapid onset of action compared to oral therapies
4. Improves hemodynamics and cardiac output 1

Management of AKI

• Hold diuretics temporarily to allow renal recovery
• Cautious fluid administration guided by hemodynamic parameters
• Monitor renal function, electrolytes, and volume status closely
• Consider low-dose inotropic support if needed for right heart function while maintaining renal perfusion

Avoiding Common Pitfalls

1. Do not continue aggressive diuresis despite AKI
2. Do not use calcium channel blockers empirically - only appropriate for vasoreactive patients (approximately 10% of PAH patients) 1
3. Do not delay prostacyclin therapy while attempting oral medications in this critically ill patient
4. Do not administer excessive fluids which could worsen right heart failure and pulmonary edema

Additional Supportive Measures

• Anticoagulation with warfarin (target INR 1.5-2.5) unless contraindicated 1
• Consider low-dose digoxin if evidence of right heart failure with low cardiac output 1
• Aggressive treatment of any respiratory infections 1

Consideration for Advanced Therapies

If the patient fails to improve with optimal medical management:

• Consider atrial septostomy as a palliative procedure or bridge to transplantation 1
• Evaluate for lung or heart-lung transplantation eligibility

Follow-up and Monitoring

• Serial assessment of functional status
• Hemodynamic monitoring to guide therapy
• Careful monitoring of renal function as AKI improves
• Consideration of combination therapy once stabilized

This critically ill patient requires immediate intervention with IV epoprostenol, which has the strongest evidence for improving survival in severe PAH, while carefully managing the competing priorities of respiratory failure and acute kidney injury.