Flash pulmonary edema

Background

  • Differentiate this from acute CHF exacerbation or hypotensive cardiogenic shock, which does not display sympathetic overdrive
  • Pts can decompensate rapidly, so rapid intervention required.
  • Pts are generally more fluid depleted despite "wet" lungs, so don't give diuretics
  • Usually hx of poorly controlled HTN
    • Acute afterload increase causes pulmonary edema and poor peripheral perfusion
    • Sympathetic surge occurs as a result of decreased systemic perfusion
    • Afterload further increases and pt rapidly decompensates

Clinical Presentation

  • Rales, crackles
  • SBP > 180 mmHg
  • Tachycardic

Differential Diagnosis

Pulmonary Edema Types

Pulmonary capillary wedge pressure <18 mmHg differentiates noncardiogenic from cardiogenic pulmonary edema[1]

Diagnostic Evaluation

Evaluation

  • Largely a clinical diagnosis

Work-up

  • CBC
  • CMP
  • BNP
  • Cardiac enzymes
  • CXR

Management

  • Key is to vasodilate arterial side, while maintaining oxygenation
  • BiPAP with PEEP of 8 mmHg
  • Titrate PEEP quickly to 12
  • High dose nitroglycerin over 2 min (at these doses, NTG has vasodilation > venodilation[2])
    • Goal BP at the pt's norm
    • Load 800 mcg over 2 min (may start at 100 mcg/min, then titrate rapidly to 400 mcg/min for 2 min)
    • Then start maintenance at 100 mcg/min, titrate up as needed
  • Give fluids to avoid decreasing BP too much (pts are likely more dehydrated that overloaded)
  • However, after critical parts under control, assess for volume overload
  • Consider captopril 12.5 - 25 mg SL for continuation of afterload reduction[3]
  • Wean CPAP after sustained BP at pt's norm[4]
    • Decrease FiO2 to 40%
    • Wean PEEP down 2 cmH2O q10 min
    • At 5 cmH2O, trial of NC

Disposition

  • Admit

See Also

References

  1. Clark SB, Soos MP. Noncardiogenic Pulmonary Edema. In: StatPearls. Treasure Island (FL): StatPearls Publishing; October 1, 2020.
  2. Haber et al. Bolus intravenous nitroglycerin predominantly reduces afterload in patients with excessive arterial elastance. J Am Coll Cardiol. 1993;22(1):251-257.
  3. Hamilton RJ, Carter WA, Gallagher JE. Rapid Improvement of acute pulmonary edema with sublingual captopril. Acad Emerg Med 1996; 3: 205-12.
  4. Weingart, S. When to wean the CPAP in SCAPE. Oct 2011. http://emcrit.org/blogpost/when-to-wean-cpap-scape/