Flash pulmonary edema

Background

• Presentation:
  • Rales, crackles
  • SBP > 180 mmHg
  • Tachycardic
• Differentiate this from acute CHF exacerbation or hypotensive cardiogenic shock, which does not display sympathetic overdrive
• Must act quick, as pt can decompensate within 5-10 minutes
• Pts are generally more fluid depleted despite "wet" lungs, so don't give furosemide
• 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

Management

• Key is to vasodilate arterial side, while maintaining oxygenation

1. • BiPAP with PEEP of 8 mmHg
   • Titrate PEEP quickly to 12
   • High dose nitroglycerin over 2 min (at these doses, NTG has vasodilation > venodilation)
   1. • 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
   • Wean CPAP after sustained BP at pt's norm
   1. • Decrease FiO2 to 40%
      • Wean PEEP down 2 cmH2O q10 min
      • At 5 cmH2O, trial of NC

References

• Weingart, S. EMCrit Podcast 1-Sympathetic Crashing Acute Pulmonary Edema. April 2009. http://emcrit.org/podcasts/scape/.