Our region recently changed our guideline for Nitro SL administration in pulmonary edema from 0.4 mg SL every 3-5 minutes as needed to 0.4-0.8 mg SL every 3-5 minutes as needed.
A new study, Prehospital High-dose Sublingual Nitroglycerin Rarely Causes Hypotension in the forthcoming October 2013 edition of Prehospital and Disaster Medicine adds more support for guidelines allowing paramedics to use high dose SL nitro when faced with patients in respiratory distress due to heart failure with hypertension.
In 2011 the New York State Western Regional Emergency Medical Advisory Council issued a new guideline allowing paramedics to give multiple Nitro SL tablets to patients in CHF, including up to 3 tabs (1.2 mg) for patients with systolic BP >200 mm Hg.
Here is the guideline:
Over a six month study period 100 patients received high doses (0.8 mg or higher) of NTG. 68% received two tabs simultaneously (0.8). 31% received three tabs (1.2) at one time. One patient received 4 (whoops) at one time.
Only 3 patients suffered post administration hypotension. All three, who had recieved two tabs, had an improvement in their breathing and all three had their hypotension resolve without further intervention.
The study’s bottom line – high dose nitro in the form of multiple SL tablets appears to be a safe treatment in the prehospital environment.
See also- NTG and the Hero Medic
Check out Rogue Medic’s comments on high-dose nitro.