The authors of the article are discussing the cardiac complications of cyanide toxicity. The study takes place in France where hydroxocobalamin is the mainstay of cyanide toxicity treatment. Hydroxocobalamin was only recently approved in the US for this indication. Prior to this, sodium thiosulfate was the mainstay of therapy (the nitrates are also included in the kits used in the US that contain sodium thiosulfate, however they are generally contraindicated in smoke inhalation patients).

Sodium thiosulfate's main drawback is its delayed onset of action, about 1.5 hours. Thus, hydroxocobalamin's approval for this indication (short onset of action, work's by scavenging CN- molecules, forming cyanocobalamin which is excreted in the urine) seems to bring the U.S. up to speed to what is being done already in many European countries. Now, to get to the good stuff. The article discusses the cardiac complications of 161 patients who were exposed to cyanide, and their treatment with hydroxocobalamin.

The Pearls I gathered from the article were:

1. Cardiac complications are EXCEEDINGLY common in cyanide toxicity (all but 26 of the 161 patients) and ranged from cardiac arrest (asystole and VF) to ST changes, bundle branch blocks, SVT, and sinus tachycardia.
2. Get an EKG on victims of significant smoke inhalation. In the patients who did not have any of the above EKG abnormalities, cyanide toxicity was not present.
3. Give hydroxocobalamin to victims of structure fires who present in cardiac arrest. There are obviously many other causes of cardiac arrest in this population (ie traumatic injuries, carbon monoxide, etc). But, it has a relatively benign side effect profile. And, there was a trend towards improved survival with increasing doses of hydroxocobalamin (read this part of the article carefully, its not a slam dunk by any means, but something to think about).
4. Give hydroxocobalamin to patients with significant EKG abormalities but who are not in cardiac arrest. For example, SVT, VTach, significant sinus tach, new conduction delays, or ST changes. According to the article, all of these improved with this medication.
5. The dose of this medication is typically 5 grams, but this can be repeated. And I would have a low threshhold for repeating it quickly given the trend towards improved outcome with doses between 5 and 10 grams, particularly in very ill patients.
6. I am not a toxicologist, or even an attending for that matter, so take my words with a grain of salt. 

The above are just a new way I will approach victims of structure fires, smoke inhalation, etc, who potentially are exposed to CN-. These are typically young, healthy patients and we have a chance to intervene. So, consider giving it empirically and immediately in the very ill or arresting patient. Get and EKG. Get an ABG.