Review of: Weber JM, Tataris KL, Hoffman JD, et al. Can nebulized naloxone be used safely and effectively by emergency medical services for suspected opioid overdose? Prehosp Emerg Care. 2012.16(2):289—92.
The Science
This is a preliminary retrospective analysis of consecutive cases of naloxone administration via a nebulizer by the Chicago Fire Department. Investigators abstracted information from EMS electronic patient care reports, which included standard demographic information and clinical data (vitals, paramedic impression, etc.). Cases of suspected opioid overdoses (ODs), altered mental status and respiratory depression were included in the analysis–totaling 105. Twenty-four patients were excluded from analysis because they didn’t meet entry criteria into the study. Investigators found that more than 80% of all patients receiving nebulized naloxone had at least some response to it. Their conclusion is that nebulized naloxone is a safe and effective means to administer naloxone to patients with suspected opioid overdoses.
Doc Wesley: One of the largest safety concerns I have for EMS providers is exposure to blood-borne pathogens. I had a high-risk needle stick in my early career when HIV/AIDS was universally fatal. Even with the retrovirals available today it just isn’t worth the risk if you can avoid it.
When it comes to caring for the suspected opiate OD, many services routinely establish vascular access and titrate naloxone. Unfortunately, some of these patients come out swinging and care becomes more complicated.
Intranasal naloxone has been shown to be effective, but this still requires you to get close to a pair of biting teeth. My experience is that the sleeping OD patient doesn’t breathe much through their nose, and it’s often so full of mucous that it impairs absorption of the drug.
These authors report their experience with a novel means of administering naloxone. There are several benefits. The first is that the patient can be provided oxygen, and their mouth is covered if they start spitting. In addition, the authors report that a third of the patients had complete response while half had a partial response. Finally, in no case was rescue airway management required, and there were no adverse events.
I’m going to look into putting this into my service’s toolbox.
Medic Marshall: I think this is a nice, straightforward study that attempts to improve our safety in the field by avoiding procedures that put providers at risk for exposure to all the bad bugs that are out there. In that regard, I think it’s great. But I’m a bit apprehensive to say we all need to start administering nebulized naloxone to patients who are breathing and are suspected opioid ODs. This is not a fault of the literature; this is clearly a preliminary report, but let’s examine what isn’t very clear.
First off, the investigators break out the cases by suspected opioid overdose, altered mental status, and respiratory depression. The problem that I see here is the potential for bias introduced into the study, in that all patients should be receiving naloxone for suspected opioid overdoses, meaning patients with altered mental status and respiratory depression actually fall into the suspected opioid overdose category. Unless I’m misinterpreting the results, the potential effect this has on the study is actually demonstrating a “less than effective” outcome.
When examining the outcomes of the responses, they’re clearly subjective. This makes interpretation difficult in that “complete” and “partial” responses aren’t clearly defined. Furthermore, 20 patients had “no response” at all to the treatment, with no explanation regarding the suspected cause. This makes me wonder what was so different about this population of patients from those that did respond. Investigators also note that 11 patients received “rescue treatment”–IV naloxone–which nine of the 11 responded to. But where did these patients come from? Were they in the “partial response” group? Were they in the “no response” group? Again, it’s difficult to ascertain this information from the data provided.
Additionally, the study design doesn’t really provide a definitive conclusion to their objective. As there was no mention of injury or exposure to the medics–something they might think about reporting in a future paper on this topic–we can only assume that naloxone was safely administered. And I’m still not entirely convinced on the claim of effectiveness. If the authors really wanted to examine safety and effectiveness of this treatment, I would suggest a prospective double-blind control trial where the administration method of naloxone is randomized to IV or nebulized and the other method is normal saline.
At the end of the day, I wouldn’t fault anyone for taking on this new method, but I would caution anyone from expecting any serious benefits.
Abstract
Background: EMS traditionally administer naloxone using a needle. Needleless naloxone may be easier when intravenous (IV) access is difficult and may decrease occupational blood-borne exposure in this high-risk population. Several studies have examined intranasal naloxone, but nebulized naloxone as an alternative needleless route has not been examined in the prehospital setting.
Objective: We sought to determine whether nebulized naloxone can be used safely and effectively by prehospital providers for patients with suspected opioid overdose.
Methods: We performed a retrospective analysis of all consecutive cases administered nebulized naloxone from January 1 to June 30, 2010, by the Chicago Fire Department. All clinical data were entered in real time into a structured EMS database and data abstraction was performed in a systematic manner. Included were cases of suspected opioid overdose, altered mental status and respiratory depression; excluded were cases where nebulized naloxone was given for opioid-triggered asthma and cases with incomplete outcome data. The primary outcome was patient response to nebulized naloxone. Secondary outcomes included need for rescue naloxone (IV or intramuscular), need for assisted ventilation and adverse antidote events. Kappa interrater reliability was calculated and study data were analyzed using descriptive statistics.
Results: Out of 129 cases, 105 met the inclusion criteria. Of these, 23 (22%) had complete response, 62 (59%) had partial response and 20 (19%) had no response. Eleven cases (10%) received rescue naloxone, no case required assisted ventilation and no adverse events occurred. The kappa score was 0.993.
Conclusion: Nebulized naloxone is a safe and effective needleless alternative for prehospital treatment of suspected opioid overdose in patients with spontaneous respirations.
