LAUSR

We appreciate Willman et al.’s thoughtful systematic review regarding the necessity of observing patients following naloxone administration for heroin overdose. Based on the available literature, the authors appropriately conclude that death is unlikely to occur in patients who refuse transport following successful reversal with naloxone [1]. However, as noted, relying on medical examiner records may systematically underestimate the patient’s true risk by neglecting serious non-death adverse events and deaths that occur in other jurisdictions. They further conclude that based on the results of a study by Christenson et al. that patients who are transported can be safely discharged from the Emergency Department after one hour of observation if they are able to mobilize as usual, have normal vital signs, and a GCS of 15 [2]. While we agree that adverse events were rarely identified in these studies, we caution against using these data to justify a shortened observation period at this time. The prediction tool reported by Christenson et al. was derived from subjects who received intravenous or subcutaneous naloxone for opioid toxicity between May 1997 and May 1998 and has not been externally validated [2]. The true composition of what patients think is heroin is often not known by patients or providers, and the presence of contaminants like carfentanil, U-47700, and other synthetic opioids calls into question the validity of using this assessment tool after a reported heroin overdose. These synthetic agents have durations of action that are unknown or that are significantly longer than heroin in animal models [3]. Although the effects of naloxone typically last for 45minutes, they can persist beyond 60minutes [4]. Furthermore, the proliferation of 2mg intranasal naloxone use by citizens and non-paramedic first responders may also impact these findings [5]. We recommend validating this tool in the current climate of synthetic opioid contamination and wide-spread intranasal naloxone use before generalizing a one hour observation period for all patients who receive naloxone after presumed heroin overdose. Providers should consider these limitations while balancing the sometimes difficult issues of patient safety and patient autonomy.