1. Implementation of an EMS-based naloxone distribution program: A qualitative evaluation. Ager EE, Purington EK, Purdy MH, et al. JACEP Open 2024; published on-line, full text available at: https://doi.org/10.1002/emp2.13300
2. Intraosseous or Intravenous Vascular Access for Out-of-Hospital Cardiac Arrest. Vallentin MF, Granfeldt A, Klittgaard TL, et al. N Engl J Med 2024; published on-line ahead of print DOI: 10.1056/NEJMoa2407616.
3. Time Savings and Safety of EMS Administration of Antibiotics for Open Fractures. Muniza AD, Gregorio DJ, Studebaker SA, et al. Prehosp Emerg Care 2024;28(8):1046-1052
4. Barriers and Enablers in Prehospital Pediatric Analgesia. Tsao HS, Sutcliffe T, Wang C, Vargas SE, Day C, Brown LL. Prehosp Emerg Care 2024: published on-line ahead of print. https://doi.org/10.1080/10903127.2024.2431586
International Prehospital Medicine Institute Literature Review, December 2024
1. Implementation of an EMS-based naloxone distribution program: A qualitative evaluation. Ager EE, Purington EK, Purdy MH, et al. JACEP Open 2024; published on-line, full text available at: https://doi.org/10.1002/emp2.13300
Drug overdoses are a leading cause of death in the United States, with opioids contributing to over 75% of overdose fatalities in 2021. Naloxone has, for many years, been the go-to medication for suspected opiate overdoses. However, time to administration is of the utmost importance. For many years, only paramedics could administer naloxone slowly. As the opioid crisis worsened, first responders of all levels were trained and equipped to administer the medication. In the last decade, training was created for the lay public to administer naloxone in suspected overdoses with variable success. In recent years, leave-behind naloxone (LBN) programs have been established in many EMS systems.
The authors of this study investigated the attitudes and experiences of both EMS providers and people who use drugs (PWUD involved in LBH naloxone programs. Semi-structured telephone interviews were conducted with personnel from a single EMS agency in the Washtenaw/Livingston County medical control authority to explore factors influencing the distribution of naloxone at opioid overdose scenes. Full-time paramedics were recruited via purposive sampling, with 60 employed at the time. An agency supervisor invited paramedics through an email with study details and consent forms. Research assistants contacted interested participants for interviews. Interviews, lasting 15-20 minutes, began with obtaining consent and included open-ended questions on participants’ attitudes toward naloxone programs, training received, and challenges faced during overdose responses. Paramedics also discussed their interest in further training on naloxone, harm reduction, and addiction.
Structured telephone interviews were conducted with individuals with lived experience of substance use to evaluate their attitudes toward receiving naloxone training from EMS personnel. Participants were sampled from a Washtenaw County substance use recovery residence and recruited through in-person invitations by the residence’s Clinical Director. To ensure accessibility, interviews were conducted via the residence’s landline telephone. Interviews began with obtaining verbal consent and proceeded with participants reflecting on their experiences with drug overdoses, including interactions with pre-hospital responders when 911 was called. The interviews concluded by exploring participants’ opinions on receiving overdose education from EMS personnel.
Out of 23 EMS participants, 18 had distributed LBN, with most agreeing that EMS agencies should implement such programs. Barriers to distribution included forgetting, patient acuity, patients refusing, and liability concerns. Facilitators included having a clear protocol, easily accessible kits, and a minimal documentation burden. Most participants expressed interest in receiving harm reduction education. Two EMS providers expressed concern that this type of program served to encourage drug use and that they could be held liable if the medication was administered incorrectly. Among the 11 PWUD participants, 8 reported recent involvement in an opioid overdose. The majority supported LBN and felt comfortable receiving naloxone training from EMS.
The authors note study limitations relating to size and single-agency selection. They also note that EMS personnel participation bias is secondary to voluntary participation in the study. This may have led to participation from providers with a positive interest in the program. Another limitation is the selection of PWUD from a residential treatment center as opposed to those in the general community. A selection bias is easily seen as those who are enrolled in treatment facilities generally have a more vested interest in treatment than those in the general community, especially those who may be unhoused.
The authors concluded that EMS personnel and PWUD overall strongly supported EMS-based naloxone distribution. Several modifiable barriers to the success of these programs were identified and warrant further investigation. EMS and harm reduction communities should advocate for expanding LBN programs across the United States. Programs like LBH naloxone combined with onsite education may augment other programs within the community.
2. Intraosseous or Intravenous Vascular Access for Out-of-Hospital Cardiac Arrest. Vallentin MF, Granfeldt A, Klittgaard TL, et al. N Engl J Med 2024; published on-line ahead of print DOI: 10.1056/NEJMoa2407616.
Out-of-hospital cardiac arrest is a common encounter for the prehospital provider, with an estimated 4 million events occurring annually worldwide. Resuscitation guidelines for patients in cardiac arrest recommend epinephrine for patients with a non-shockable rhythm (asystole or pulseless electrical activity) and epinephrine in combination with amiodarone or lidocaine in patients with a shockable rhythm (ventricular fibrillation or pulseless ventricular tachycardia). Vascular access must be obtained prior to administration of these drugs to the patient in cardiac arrest. The two options for vascular access are intravenous (IV) or intraosseous (IO). International guidelines recommend the establishment of IV access for the initial attempts at vascular access, although the data to support this recommendation is limited.
This study, called the Intraosseous Vascular Access during Out-of-Hospital Cardiac Arrest (IVIO) trial, is an attempt to determine which route of administration (IV vs IO) results in a higher return of spontaneous circulation (ROSC). The study took place in all five EMS regions of Denmark, with a study population of 5.9 million people. Prehospital cardiac arrests in Denmark a typically attended by an ambulance unit and a physician-manned unit. The physician may terminate resuscitation efforts on-scene.
The study population was any patient 18 years of age or older in cardiac arrest and requiring vascular access. Exclusion criteria included a suspected traumatic cause of the cardiac arrest, functioning vascular access already in place at the time of randomization in the trial, and previous enrollment in the trial. The patient was randomized on-scene by a provider opening an opaque, sealed envelope. The patients were randomly assigned in a 1:1 ratio to undergo either IO (EZ-IO) or IV (Venflon Pro Safety) access. Patients who were randomly assigned the IO route were further randomized to receive either humeral or tibial access in a 1:1 ratio. The main comparison in the trial was IV vs IO, with humeral vs tibial access as a secondary comparison. The primary outcome was sustained ROSC, defined as a palpable pulse or other signs of circulation without the further need for chest compressions for at least 20 minutes. Secondary outcome measures were survival at 30 days and survival at 30 days with a favorable neurologic outcome.
A total of 1479 patients were eligible for inclusion in the primary analysis; 731 received IO access and 748 received IV access. The mean age of the patients was 69 +/- 15 years and 70% were men. Most of the cardiac arrests occurred at home (81%) with an initial non-shockable rhythm in 77% of patients. Of the enrolled patients, 44 (6%) randomized to IO and 25 (3%) randomized to IV access never underwent any attempt at vascular access due to early termination of resuscitation (78%) or an early ROSC (22%). Access was obtained in the first or second attempt in 92% of the IO group and 80% of the IV group. The time to first successful vascular access was similar among the two groups, as was the time to the first dose of epinephrine. ROSC (the primary outcome) occurred in 221 IO patients (30%) and in 214 IV patients (29%). At 30 days, 85 IO patients (12%) and 75 IV patients (10%) were alive. The number of patients who were alive at 30 days with a favorable neurologic outcome was 67 in the IO group (9%) and 59 in the IV group (8%). Adverse events (extravasation, compartment syndrome, osteomyelitis, bone fracture, necrosis, or phlebitis) from both access techniques were not noted.
For the 731 patients in the IO group, 361 were randomly selected for humeral access and 370 to tibial access. The incidence of successful first or second attempt access was 90% among the humeral group and 93% among the tibial group. ROSC occurred in 108 (30%) of humeral access patients and 113 (31%) of tibial access patients. CT scans were obtained in 32 humeral patients and 35 tibial access patients. The catheter was considered correctly positioned in the bone marrow in 23 (71%) humeral access patients and in all 35 (100%) tibial access patients. Half of the patients in the humeral access group had catheters that were bent at the time of CT as compared to 11% of patients in the tibial group.
There are several limitations to this study. It was powered for an analysis of ROSC, not for more patient-centered outcomes such as long-term survival. While they did include this in the study, the sample size would need to be much larger to note any true effect. It was not a randomized study, so clinicians were aware of the randomization assignments for their patient. The results may not be generalizable to other EMS systems with different levels of experience or equipment. Lastly, the authors reported that first pass IO was more successful than first pass IV (85% vs 65%) yet the time to medication administration was the same. This should have a detailed explanation for this finding.
This study demonstrates no significant difference in ROSC between IO and IV access in adults with out-of-hospital medical cardiac arrest. It is a well-designed study published in a highly regarded journal and its results should prompt consideration for protocol redesign to include IO access as an option for primary vascular access in these patients.
3. Time Savings and Safety of EMS Administration of Antibiotics for Open Fractures. Muniza AD, Gregorio DJ, Studebaker SA, et al. Prehosp Emerg Care 2024;28(8):1046-1052
Leading trauma care organizations recommend early administration of antibiotics to prevent infection associated with trauma. With regards to open fractures, the American College of Surgeons (ACS) recommends that antibiotics be given to all patients with open fractures within one hour of arrival at an emergency department. The British Orthopedic Association Standard for Trauma (BOAST) reduces that time standard to antibiotics within one hour of injury, not arrival at a hospital. Previous studies reveal that even ACS trauma centers have challenges in meeting the one-hour benchmark (47%). The Committee for Tactical Combat Casualty Care long ago empowered the warrior medic to begin antibiotic prophylaxis at the point and time of injury. This study examined whether or not administering antibiotic prophylaxis for open fractures in civilian EMS programs will reduce the time to antibiotic prophylaxis and therefore infection rates and if antibiotic therapy by paramedics safe or will it result in high rates of anaphylaxis or allergic reactions?
This is a retrospective observational study that the Dell Medical School at the University of Texas’ institutional review board determined was exempt from review. De-identified data were obtained for calendar years 2019-2022 via the ESO Collaborative, a 2,000-member collaborative of EMS agencies that volunteer their electronic health record (EHR) data for research. The collaborative also has access to bidirectional data linking EMS EHR’s to hospital discharge diagnosis.
Patients were first culled for International Classification of Disease 10th Edition (ICD 10) code for open extremity fractures. Patients less than nine years of age were excluded along with patients who did not encounter EMS as a 9-1-1 emergency. Lastly, patients were split into two groups: those that did not (11,737) and those that did (523) receive prehospital antibiotics. For patients that received prehospital antibiotics, cefazolin was used most frequently (88.3%) followed by ceftriaxone (10.7%).
The median time from dispatch of the EMS unit to initiation of prehospital antibiotics was 31 minutes (24-41). Almost all patients that received prehospital antibiotics received them within 60 minutes of EMS dispatch (96.6%). Greater than twenty-five percent of the patients that received prehospital antibiotics experienced prehospital times greater than one hour. Without prehospital antibiotics, that subset of patients would not have received antibiotic prophylaxis within the BOAST recommendation of antibiotics within 60 minutes of injury. The authors report a median time saved of 15 minutes (8-22) by prehospital antibiotic administration. It was also noted that the patients that received antibiotics group experienced a five minute longer scene time interval than the other cohort.
Epinephrine administration was used as a marker for presumed anaphylaxis and diphenhydramine for an allergic reaction. No patients in the prehospital antibiotic group received epinephrine. Only one patient in that group received diphenhydramine. In the no-prehospital antibiotic group, three patients received epinephrine and seven were given diphenhydramine.
ICD-10 codes for infections were also assessed for each cohort group. Five patients (1.0%) that received prehospital antibiotics were coded with ICD-10 infection codes. One hundred fifty-nine patients (1.4%) in the did not receive prehospital antibiotics group were coded as having infections. The authors state that their study was not designed or powered (12,000 participants per cohort) to detect a statistically significant difference in infection rates.
There were limitations to this work. The first being its retrospective observational design. The ESO collaborative may underrepresent rural EMS systems where prehospital antibiotics could potentially be beneficial in reducing time of injury to time of antibiotic administration. Lastly, time savings was based on the robust assumption that IV antibiotics would be administered soon after arrival at an emergency department. In addition, the use of ICD-10 codes to look for infection may have identified infections that were unrelated to the open fractures.
Prehospital providers empowered to administer prehospital antibiotics in this paper were able to do so safely for patients with open fractures. Their median time of doing this was 15 minutes prior to arrival at the emergency department. Almost all of the patients that received prehospital antibiotics (99%) received them within 60 minutes of EMS dispatch. Unfortunately, the study design was not sufficiently powered to determine a statistically significant difference in infection rates. This study, like many others, shows that an intervention can be safely and quickly performed in the prehospital setting but not whether or not it makes a difference to the patient’s clinical outcome.
4. Barriers and Enablers in Prehospital Pediatric Analgesia. Tsao HS, Sutcliffe T, Wang C, Vargas SE, Day C, Brown LL. Prehosp Emerg Care 2024: published on-line ahead of print. https://doi.org/10.1080/10903127.2024.2431586
Approximately 5-10% of EMS transports in the United States involve pediatric patients. Pediatric patients are a vulnerable population for unrecognized pain and under treatment of that pain. Data from the National Emergency Medical Services Information System suggest that less than 20% of children, under the age of 15 years, transported by EMS for fractures, burns or penetrating injuries received pain medication by EMS. That percentage decreased to 6.4% in the less than 3 years of age group. Untreated pain in children often leads to increased anxiety, decreasing pain tolerances and increased fear of medical interactions.
Across EMS there are common enablers and barriers to providing analgesia to the pediatric population. Provider barriers include the inability to accurately assess pain, increased patient pain and agitation gaining IV access to administer pain medications, fear of anaphylaxis from pain medications, provider unfamiliarity treating pediatrics and pain medications, the feeling that hospital care of pain is optimal over field care and lastly, not wanting to gain attention from EMS authority figures. Provider enablers include the belief that the pediatric patient population should receive analgesia for painful injuries, pediatric specific analgesia and care education, support from agency leadership, positive interactions with on-line medical control and the widespread availability of assistive guides.
The state of Rhode Island directs patient care via a standardized statewide protocol system. At the time of this study (2020) Rhode Island had 4,882 licensed prehospital providers (5 emergency medical responders, 2,032 EMTs, 3 AEMTs, 2,301 AEMT-Cardiacs and 541 paramedics). It is worth noting that by state law, every Rhode Island licensed ambulance service must have a Pediatric Emergency Care coordinator (PECC). By statewide treatment protocols, both Rhode Island Paramedics and “Cardiac Techs” (AEMT-C) are authorized to administer intranasal (IN) or intravenous (IV) fentanyl for pediatric pain management with the assistance of a pediatric dosing guide. Paramedics are further authorized to administer IV or IM ketorolac for mild or moderate pain and IV/IM/IN ketamine for severe pain.
The authors of this Rhode Island Hospital institutional review board approved focus group study attempted to identify additional enablers and barriers to pediatric analgesia by prehospital providers. Participants were Rhode Island licensed prehospital providers and they were interviewed during two focus group video conferences. Each focus group session lasted approximately 60 minutes. The trained facilitator for the focus groups was not an EMS clinician. A research assistant “scribe” sat in on each session and took notes. The facilitator-initiated conversation via open ended questions focusing on scenarios where pediatric patients were transported in pain, decision making factors relating to treating pediatric pain, available pain management assessment tools, patient family reactions, personal opinions about current pediatric protocols and available tools and educational opportunities to learn about pain management for children.
Sixteen prehospital providers participated in one of two focus groups (2 EMTs, 5 AEMT-Cs and 5 Paramedics). All were white and overwhelmingly male (2 F, 14 M). The mean number for years of experience was 20 years. Two of the participants were PECCs. The focus groups identified three common themes; “Lack of Experience with Pediatric Patients Among EMS Clinicians”, “Medical Control is a Helpful Resource … But with Limits” and “Training is Important, But Not a Substitute for Experience”.
From these themes, the authors identified new or additional enablers and barriers to pediatric analgesia. The enablers included longer transport times and EMS provider comfort with the use of IN medication administration (from frequent use of IN Narcan for opiate overdose reversal). The barriers were rough riding ambulances making it difficult to establish an IV for medication administration, lack of knowledge about available EMS medications, lack of real-world training for pediatric encounters, difficulty with pediatric weight estimation and lack of education on pediatric analgesic medication safety profiles.
Limitations of this study included the use of a virtual platform to conduct the two focus group meetings, the use of only Rhode Island based providers which limits participant and patient demographics, and not convening additional focus groups using different qualitative methods to gather data. The small number of participants may also be a limitation.
Pediatric patient transports can be anxiety inducing for both the EMS provider and the patient. While there is no substitute for clinical experience with pediatrics to gain confidence in their care, quality education and high-fidelity simulation using actual patient scenarios may increase provider confidence in providing care to one of our most vulnerable populations. Part of that confidence in care should include pain assessment and management for children. All providers should be familiar with what options are available for them to provide to ease patient pain and suffering. EMS leaders and managers should engage with their providers to avail them of the education and resources needed to confidently meet the needs of pediatric patients, including analgesia.
