Abstract
To the Editor:
We express our gratitude for the insightful comments and the additional discussion 1 generated by our article titled “Time to Reconsider Analgesia in Mass Casualty Incidents.” 2 We strongly believe that we can improve the early access of analgesia to mass casualty incident (MCI) victims. Our article focuses on analgesia in the initial phase of mass casualty events, when the number of victims overwhelms normally available resources. In this phase, the priority is triage and identification of severely injured patients who may benefit from life-saving treatment and/or evacuation.
Simple tools such as fentanyl lozenges and methoxyflurane inhalers may allow for early analgesia in MCI settings. However, we purposely omitted regional anesthesia for the same reason we suggested that IV (intravenous) analgesia was inadequate, as cannulation and titration prove to be excessively time- and resource-consuming in the very early phase of an MCI. While regional anesthesia is indeed a very effective analgesic option, it requires both time and a very specific skillset only available to anesthesiologists and some emergency medicine physicians to be safely and adequately performed. In the very early phases of an MCI, resources are often scarce, and committing highly skilled personnel to provide regional anesthesia could be an inadequate allocation of valuable resources. However, in later stages, when resources become plentiful, regional anesthesia is invaluable in providing high-quality analgesia. This is especially true for victims of entrapment or patients who require amputations. High-profile disasters such as the 2010 earthquake in Haiti have shown that regional anesthesia can be implemented in disaster zones with great results. 3 Regional anesthesia has also been successfully used in austere and remote environments and has even been recommended as an effective means of analgesia in the 2014 update of the Wilderness Medical Society practice guidelines for the treatment of acute pain in remote environments. 4 As you stated, prehospital regional anesthesia has been used for many years, and its feasibility and effectiveness are undeniable. There is even evidence that it may be superior to analgo-sedation for the reduction of dislocated extremity injuries. 5 The risk of local anesthetic systemic toxicity (LAST) is low, and the use of ultrasound has been instrumental in further reducing the incidence of this serious complication. 6 Given the widespread availability of cheap portable ultrasound machines, it seems judicious to provide regional anesthesia using an ultrasound-guided technique rather than a landmark and/or nerve-stimulator-guided technique. Other tools, such as mobile apps to calculate maximal local anesthetic dose may increase safety. 7
In the aftermath of a disaster, regional anesthesia is essential to provide quality postoperative pain control, especially in patients who have undergone amputations, as this reduces the incidence of phantom and chronic pain. 8 Chest wall blocks such as the erector spinae block (ESP) or the serratus anterior plane block are easy to deliver and provide quality analgesia for chest injuries with associated rib fractures. 9 These blocks can either be done as a single shot or using a catheter-based approach for prolonged analgesia and provide an alternative to epidural analgesia, especially in patients with unilateral injuries. Chest wall blocks allow patients to mobilize and cough, and ultimately help reduce respiratory complications.10,11
In conclusion, providing good-quality analgesia to patients in MCIs is essential. While not appropriate for the very early stage of an MCI, regional anesthesia provides excellent, long-lasting analgesia and can even be delivered in the prehospital setting when sufficient resources are available. Providing regional anesthesia to patients not only allows for effective pain control but also offers medium to long-term benefits, such as reducing the occurrence of respiratory complications and the incidence of chronic pain. Strategies to provide regional anesthesia after MCIs must be planned accordingly.