Prehospital Pericardiocentesis Using a Pneumothorax Needle.

Case: We discuss a patient with a penetrating knife wound to the chest who lost pulses from cardiac tamponade. Prehospital ultrasound was able to quickly identify the tamponade and a pericardiocentesis was performed using a Simplified Pneumothorax Emergency Air Release (SPEARTM) Needle (North American Rescue, LLC, USA) with subsequent return of spontaneous circulation. Discussion: Penetrating chest trauma carries significant morbidity and mortality. In traumatic cardiac arrest due to a penetrating mechanism, it is paramount that the patient be transported to a trauma center as quickly as possible. Prehospital pericardiocentesis is a potential life-saving intervention.

The Hennepin Ketamine Study Investigators' Reply.

We read with interest the recent editorial, "The Hennepin Ketamine Study," by Dr. Samuel Stratton commenting on the research ethics, methodology, and the current public controversy surrounding this study.1 As researchers and investigators of this study, we strongly agree that prospective clinical research in the prehospital environment is necessary to advance the science of Emergency Medical Services (EMS) and emergency medicine. We also agree that accomplishing this is challenging as the prehospital environment often encounters patient populations who cannot provide meaningful informed consent due to their emergent conditions. To ensure that fellow emergency medicine researchers understand the facts of our work so they may plan future studies, and to address some of the questions and concerns in Dr. Stratton's editorial, the lay press, and in social media,2 we would like to call attention to some inaccuracies in Dr. Stratton's editorial, and to the lay media stories on which it appears to be based.Ho JD, Cole JB, Klein LR, Olives TD, Driver BE, Moore JC, Nystrom PC, Arens AM, Simpson NS, Hick JL, Chavez RA, Lynch WL, Miner JR. The Hennepin Ketamine Study investigators' reply. Prehosp Disaster Med. 2019;34(2):111-113.

A brief assessment of capacity to consent instrument in acutely intoxicated emergency department patients.

OBJECTIVE: The aim of this study was to determine to what extent acute alcohol intoxication effects capacity to assent, consent, or refuse research participation. METHODS: This was a prospective, observation study performed at our inner city, county hospital with >100,000 annual emergency department visits. Non-pregnant, English speaking patients older than 18 with evidence of acute alcohol intoxication were considered eligible. After medical screening, a trained research associate presented the study version of the University of California, San Diego Brief Assessment of Capacity to Consent (UBACC) tool. The primary outcome was the number of patients able to correctly respond to all 10 questions. RESULTS: Of 642 screened patients, 415 patients were enrolled and completed the tool. The mean alcohol concentration was 227mg/dL (range 25-500mg/dL). Sixteen patients (3.9%) answered all 10 questions correctly; by definition of the UBACC, these patients were deemed to possess capacity to consent. Mean alcohol concentrations in the capacity group were lower than in those lacking capacity; 182mg/dL (SD 6.7) versus 229mg/dL, (SD 7.9). Of the 287 patients who were interviewed upon sobriety at discharge, 182 patients (63.4%) did not recall completing the questionnaire. CONCLUSIONS: While intoxicated emergency department patients are able to complete the questionnaire, the majority do not possess capacity to provide informed consent to research. A minority of participants remember involvement once they have achieved sobriety, exception from informed consent protocols are needed to perform emergency research in this population.

A prospective study of ketamine as primary therapy for prehospital profound agitation.

OBJECTIVE: We investigated the effectiveness of ketamine as a primary therapy for prehospital profound agitation. METHODS: This was a prospective observational study of patients receiving 5mg/kg of intramuscular ketamine for profound agitation, defined as a score of +4 on the Altered Mental Status Scale (AMSS), a validated ordinal scale of agitation from -4 (unresponsive) to +4 (most agitated). The primary outcome was time to adequate sedation (AMSS<+1). Secondary outcomes included need for additional sedatives, intubation frequency, complications associated with ketamine, and mortality. RESULTS: Forty-nine patients were enrolled. Median age was 29years (range 18-66); 76% (37/49) were male. Median time to adequate sedation was 4.2min (95% CI: 2.5-5.9, range 1-25min) and 90% (44/49) had adequate sedation prehospital. Seven patients (14%) received a second sedative prehospital. Intubation occurred in 57% (28/49) of patients. Mechanical ventilation lasted <24h in 82% (23/28) of patients, and <48h in 96% (27/28) of patients. A single physician intubated 36% (10/28) of the patients. Complications related to ketamine included hypersalivation (n=9, 18%), vomiting (n=3, 6%), and emergence reaction (n=2, 4%). One patient died from complications of septic shock on hospital day 29, likely unrelated to ketamine. CONCLUSIONS: In patients with prehospital profound agitation, ketamine provides rapid effective sedation when used as a primary therapy. Intubation was common but accompanied by a short duration of mechanical ventilation and appears to have been subject to individual physician practice variation.

Intubation of Profoundly Agitated Patients Treated with Prehospital Ketamine.

BACKGROUND: Profound agitation in the prehospital setting confers substantial risk to patients and providers. Optimal chemical sedation in this setting remains unclear. OBJECTIVE: The goal of this study was to describe intubation rates among profoundly agitated patients treated with prehospital ketamine and to characterize clinically significant outcomes of a prehospital ketamine protocol. METHODS: This was a retrospective cohort study of all patients who received prehospital ketamine, per a predefined protocol, for control of profound agitation and who subsequently were transported to an urban Level 1 trauma center from May 1, 2010 through August 31, 2013. Identified records were reviewed for basic ambulance run information, subject characteristics, ketamine dosing, and rate of intubation. Emergency Medical Services (EMS) ambulance run data were matched to hospital-based electronic medical records. Clinically significant outcomes are characterized, including unadjusted and adjusted rates of intubation. RESULTS: Overall, ketamine was administered 227 times in the prehospital setting with 135 cases meeting study criteria of use of ketamine for treatment of agitation. Endotracheal intubation was undertaken for 63% (85/135) of patients, including attempted prehospital intubation in four cases. Male gender and late night arrival were associated with intubation in univariate analyses (χ2=12.02; P=.001 and χ2=5.34; P=.021, respectively). Neither ketamine dose, co-administration of additional sedating medications, nor evidence of ethanol (ETOH) or sympathomimetic ingestion was associated with intubation. The association between intubation and both male gender and late night emergency department (ED) arrival persisted in multivariate analysis. Neither higher dose (>5mg/kg) ketamine nor co-administration of midazolam or haloperidol was associated with intubation in logistic regression modeling of the 120 subjects with weights recorded. Two deaths were observed. Post-hoc analysis of intubation rates suggested a high degree of provider-dependent variability. CONCLUSIONS: Prehospital ketamine is associated with a high rate of endotracheal intubation in profoundly agitated patients; however, ketamine dosing is not associated with intubation rate when adjusted for potential confounders. It is likely that factors not included in this analysis, including both provider comfort with post-ketamine patients and anticipated clinical course, play a role in the decision to intubate patients who receive prehospital ketamine. Olives TD , Nystrom PC , Cole JB , Dodd KW , Ho JD . Intubation of profoundly agitated patients treated with prehospital ketamine. Prehosp Disaster Med. 2016;31(6):593-602.

A prospective study of ketamine versus haloperidol for severe prehospital agitation.

CONTEXT: Ketamine is an emerging drug for the treatment of acute undifferentiated agitation in the prehospital environment, however no prospective comparative studies have evaluated its effectiveness or safety in this clinical setting. OBJECTIVE: We hypothesized 5 mg/kg of intramuscular ketamine would be superior to 10 mg of intramuscular haloperidol for severe prehospital agitation, with time to adequate sedation as the primary outcome measure. METHODS: This was a prospective open label study of all patients in an urban EMS system requiring chemical sedation for severe acute undifferentiated agitation that were subsequently transported to the EMS system's primary Emergency Department. All paramedics were trained in the Altered Mental Status Scale and prospectively recorded agitation scores on all patients. Two 6-month periods where either ketamine or haloperidol was the first-line therapy for severe agitation were prospectively compared primarily for time to adequate sedation. Secondary outcomes included laboratory data and adverse medication events. RESULTS: 146 subjects were enrolled; 64 received ketamine, 82 received haloperidol. Median time to adequate sedation for the ketamine group was 5 minutes (range 0.4-23) vs. 17 minutes (range 2-84) in the haloperidol group (difference 12 minutes, 95% CI 9-15). Complications occurred in 49% (27/55) of patients receiving ketamine vs. 5% (4/82) in the haloperidol group. Complications specific to the ketamine group included hypersalivation (21/56, 38%), emergence reaction (5/52, 10%), vomiting (5/57, 9%), and laryngospasm (3/55, 5%). Intubation was also significantly higher in the ketamine group; 39% of patients receiving ketamine were intubated vs. 4% of patients receiving haloperidol. CONCLUSIONS: Ketamine is superior to haloperidol in terms of time to adequate sedation for severe prehospital acute undifferentiated agitation, but is associated with more complications and a higher intubation rate.

The neurocognitive effects of simulated use-of-force scenarios.

While the physiologic effects of modern conducted electrical weapons (CEW) have been the subject of numerous studies, their effects on neurocognitive functioning, both short-term and long-term, are less well understood. It is also unclear how these effects compare to other use-of-force options or other arrest-related stressors. We compared the neurocognitive effects of an exposure to a TASER(®) (TASER International, Inc, Scottsdale, AZ) X26™ CEW to four other use-of-force scenarios during a training exercise using a well-established neurocognitive metric administered repeatedly over 1 h. Overall, we found that there was a decline in neurocognitive performance immediately post-scenario in all groups, but this effect was transient, of questionable clinical significance, and returned to baseline by 1 h post-scenario.

Markers of acidosis and stress in a sprint versus a conducted electrical weapon.

Both profound acidosis and catecholamine excess have been proposed as underlying physiologic derangements in subjects at high risk for arrest related death (ARD). In this study, the objective was to determine a level of physical exertion that is "equivalent" in terms of levels of acidosis and catecholamines to a "standard" TASER X26 exposure. Data were collected on subjects who underwent a 5-s TASER X26 exposure or a sprint of variable distances during a law enforcement training exercise. Our results show that levels of acidosis and catecholamines are less among subjects exposed to the TASER X26 than among subjects who sprinted 20 yards or more.

Successful management of excited delirium syndrome with prehospital ketamine: two case examples.

Excited delirium syndrome (ExDS) is a medical emergency usually presenting first in the prehospital environment. Untreated ExDS is associated with a high mortality rate and is gaining recognition within organized medicine as an emerging public safety problem. It is highly associated with male gender, middle age, chronic illicit stimulant abuse, and mental illness. Management of ExDS often begins in the field when first responders, law enforcement personnel, and emergency medical services (EMS) personnel respond to requests from witnesses who observe subjects exhibiting bizarre, agitated behavior. Although appropriate prehospital management of subjects with ExDS is still under study, there is increasing awareness of the danger of untreated ExDS, and the danger associated with the need for subject restraint, whether physical or chemical. We describe two ExDS patients who were successfully chemically restrained with ketamine in the prehospital environment, and who had good outcomes without complication. These are among the first case reports in the literature of ExDS survival without complication using this novel prehospital sedation management protocol. This strategy bears further study and surveillance by the prehospital care community for evaluation of side effects and unintended complications.

Prehospital chemical restraint of a noncommunicative autistic minor by law enforcement.

When responders are dealing with an agitated patient in the field, safety for all involved may sometimes only be accomplished with physical or chemical restraints. While experiences using chemical restraint in the prehospital setting are found in the medical literature, the use of this by law enforcement as a first-response restraint has not previously been described. We report a case of successful law enforcement-administered sedation of a noncommunicative, autistic, and violent minor using intramuscular droperidol and diphenhydramine. Although this case has some unique characteristics that allowed chemical restraint to be given by the law enforcement agency, it calls attention to some specific prehospital issues that need to be addressed when dealing with autistic patients with extreme agitation.