Naloxone (Narcan) Induced Pulmonary Edema John Cunha, DO, FACOEP Holy Cross Hospital Oakland Park EMS Medical Director

Naloxone (Narcan) Use Used to reverse the respiratory depression effects of opioids Dosed from 0.4mg-4mg per dose depending on the patient’s response Given in small doses until patient’s respiratory rate increases

Naloxone (Narcan) Major Side-effects Hypertension Ventricular arrhythmias Cardiac arrest Seizures Pulmonary edema

Flash Pulmonary Edema Extremely rare event First reported in anesthetized lab animals Seems to be related to higher doses of Narcan given and rapidity of reversal IV infusion may be more likely to precipitate rapid reversal and side-effects

Flash Pulmonary Edema-SIGNS Sudden dropping O2 sat Tachypnea Hypertension (could be followed by hypotension) Feeling of Shortness of Breath Rales throughout lung fields

Flash Pulmonary Edema-WHY? In opiate dependent patients, naloxone causes catecholamine (epinephrine) release leading to pulmonary edema The mechanisms for the increase in epinephrine following the administration of naloxone include its direct antagonizing effects on mu-opioid receptors Sudden overwhelming drug withdrawal symptoms-causing “Fight or Flight”

Flash Pulmonary Edema-WHY? Increases in plasma concentrations of epinephrine by 30-fold—“Fight or Flight” HUGE Increases in Cardiac Output Increases in blood pressure and heart rate The above hemodynamic effects appeared to be more pronounced if the baseline PCO2 was elevated (Patients with longer downtime)

Flash Pulmonary Edema-WHY? In the lung tissue epinephrine leads to leaking of pulmonary capillaries This leads to accumulation of pulmonary fluid (Rales on auscultation) May also be related to the release of histamine within the lung tissue Secondary to the epi or the opioid itself This is the edema

Flash Pulmonary Edema-SIGNS Sudden dropping O2 sat Tachypnea Hypertension (could be followed by hypotension) Feeling of Shortness of Breath Rales throughout lung fields

What to do??? Ensure adequate oxygenation and ventilation Give narcan in small frequent doses until respiratory depression is reversed High flow oxygen Nitroglycerin 0.4mg SL if no hypotension (repeat per protocol) Lasix 20 mg IV if no hypotension (If available) Administer CPAP with 10 cm H2O PEEP (medical procedure 4.12) Intubate if necessary

SOURCES http://www.ebmconsult.com/articles/mechanism-naloxone-related-pulmonary-edema-opiate-opioid-overdose-reversal Florida Regional Common EMS Protocols Chest, Oct. 2007, Vol. 132, No. 4 http://journal.publications.chestnet.org/article.aspx?articleid=1094181