View source for Flash pulmonary edema

==Background==
*Also known as "sympathetic crashing acute pulmonary edema" (SCAPE)
*Different from acute [[CHF]] exacerbation or hypotensive [[cardiogenic shock]], which do not have sympathetic overdrive
*Patients can decompensate rapidly, so rapid intervention required
*Patients are generally more fluid depleted despite "wet" lungs, so do ''not'' give diuretics
*Usually history of poorly controlled [[hypertension]]
**Acute afterload increase causes [[pulmonary edema]] and poor peripheral perfusion
**Sympathetic surge occurs as a result of decreased systemic perfusion
**Afterload further increases and patient rapidly decompensates

==Clinical Features==
[[File:Elevated JVP.jpg|thumb|Marked jugular venous distension (arrow).]]
[[File:PedalEdema.jpg|thumb|Pitting pedal edema]]
*Rales, crackles
*[[Hypertensive emergency|SBP >180 mmHg]]
*[[Tachycardia]]
*[[Tachypnea]]

==Differential Diagnosis==
{{Pulmonary edema types}}

==Evaluation==
[[File:PulmEdema.png|thumb|Pulmonary edema with small pleural effusions on both sides.]]
[[File:Kerley-B-Linien.jpg|thumb|Kerley B lines in acute cardiac decompensation. The short, horizontal lines can be found everywhere in the right lung.]]
===Workup===
*CBC (rule out anemia)
*Chem
*[[ECG]]
*[[CXR]] - '''signs of pulmonary congestion may not show for hours after acute flash pulmonary edema, so normal CXR is frequently seen'''
**Cephalization
**Interstitial edema
**Pulmonary venous congestion
**[[Pleural effusion]]
**Alveolar edema 
**Cardiomegaly
*[[Troponin]]
*[[Echocardiography]]
**Bedside to assess [[Cardiac ultrasound|global function]], [[Ultrasound: lungs|B lines]], [[IVC ultrasound|assessment of IVC]]
**Formal TTE/TEE
*Consider [[arterial line]] monitoring for titration of NTG

{{BNP value}}
{{Lung ultrasound pulmonary edema}}

==Management==
[[File:Starling.jpg|thumbnail|Goal in heart failure management is to reduce preload (EDV), to reach higher SV on Frank Starling curve.]]
''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, [[nitroglycerin]] has vasodilation > venodilation<ref>Haber et al. Bolus intravenous nitroglycerin predominantly reduces afterload in patients with excessive arterial elastance. J Am Coll Cardiol. 1993;22(1):251-257.</ref>)
**Goal BP at the patient'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
**NOTE: it takes time to set up [[nitroglycerin]] drip, so consider SL [[nitroglycerin]] in interim
***0.4mg tab during 5 min = ~80 mcg/min (2 tabs = ~160 mcg/min, etc.)
***Difficult to titrate if giving more than 1-2 tabs
*Patients are likely more dehydrated that overloaded but should be recurrently volume assessed
*Consider [[captopril]] 12.5 - 25mg SL for continuation of afterload reduction<ref>Hamilton RJ, Carter WA, Gallagher JE.  Rapid Improvement of acute pulmonary edema with sublingual captopril.  Acad Emerg Med 1996; 3: 205-12.</ref>
*Wean CPAP after sustained BP at patient's baseline
**Decrease FiO2 to 40%
**Wean PEEP down 2 cm H2O q10 min
**At 5 cmH2O, trial of NC

===Other Interventions===
*[[Furosemide]]
**Targets kidneys which are poorly perfused in BOTH hypotension and catecholamine surge
**Consider waiting until BiPAP and [[nitroglycerin]] control hypertension first
*[[Nitroprusside]], alternative when insufficient response to NTG
**Start 0.5 mcg/kg/min, titrate to blood pressure
**Max 10 mcg/kg/min for x10 min
**Cyanide toxicity risk increases proportionately with infusion rate as well as length of time<ref>GlobalRPH. Nitroprusside (Nipride®). http://www.globalrph.com/nitroprusside_dilution.htm</ref>
*If intubation required, consider [[delayed sequence intubation]]

==Disposition==
*Admit

==See Also==
*[[Pulmonary edema]]
*[[CHF]]

==External Links==
*[http://emcrit.org/podcasts/scape/ EMCrit Podcast - Sympathetic Crashing Acute Pulmonary Edema]
*[http://emcrit.org/blogpost/when-to-wean-cpap-scape/ EMCrit Podcast - When to wean the CPAP in SCAPE]
*[http://emergencymedicinecases.com/episode-4-acute-congestive-heart-failure/ Emergency Medicine Cases Podcast - Acute Congestive Heart Failure]

==References==
<references/>

[[Category:Pulmonary]]
[[Category:Critical_Care]]