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.     

Ketamine for emergency sedation of agitated patients: A systematic review and meta-analysis

Prior studies suggest that ketamine is effective for acute agitation in the emergency department (ED) and prehospital settings. This systematic review and meta-analysis aims to evaluate the rate of sedation and need for airway management in patients given ketamine for management of acute agitation. Methods: We performed a systematic review of publications describing the use of ketamine to control agitation in the ED and prehospital settings. Studies were included if they included agitated patients, used ketamine to control agitation, occurred in the ED and prehospital setting and measured sedation status or need for airway management. Following data abstraction, a meta-analysis was performed to synthesize the rate of effective sedation and the need for airway management. Result: 13 studies met the inclusion criteria. 10 studies were conducted in the prehospital setting and 3 in the ED setting. The overall proportion of subjects receiving airway management across all 13 studies was 20% (95% CI = 0.0489–1.6505). The estimate of the proportion of subjects that achieved sedation was 85% (95% CI = 0.71–0.93). After synthesizing data from the four studies that compared ketamine to controls, ketamine was associated with increased rates of sedation (RR, 1.95 [CI, 0.47–8.1]) and increased need for intubation (RR, 2.44 [CI, 0.75–7.91]). The differences were not significant by random effects model.     

Laryngospasm and hypoxia after intramuscular administration of ketamine to a patient in excited delirium

An advanced life support emergency medical services (EMS) unit was dispatched with law enforcement to a report of a male patient with a possible overdose and psychiatric emergency. Police restrained the patient and cleared EMS into the scene. The patient was identified as having excited delirium, and ketamine was administered intramuscularly. Sedation was achieved and the patient was transported to the closest hospital. While in the emergency department, the patient developed laryngospasm and hypoxia. The airway obstruction was overcome with bag-valve-mask ventilation. Several minutes later, a second episode of laryngospasm occurred, which again responded to positive-pressure ventilation. At this point the airway was secured with an endotracheal tube. The patient was uneventfully extubated several hours later. This is the first report of laryngospam and hypoxia associated with prehospital administration of intramuscular ketamine to a patient with excited delirium.     

Laryngospasm and Hypoxia After Intramuscular Administration of Ketamine to a Patient in Excited Delirium

Abstract

An advanced life support emergency medical services (EMS) unit was dispatched with law enforcement to a report of a male patient with a possible overdose and psychiatric emergency. Police restrained the patient and cleared EMS into the scene. The patient was identified as having excited delirium, and ketamine was administered intramuscularly. Sedation was achieved and the patient was transported to the closest hospital. While in the emergency department, the patient developed laryngospasm and hypoxia. The airway obstruction was overcome with bag–valve–mask ventilation. Several minutes later, a second episode of laryngospasm occurred, which again responded to positive-pressure ventilation. At this point the airway was secured with an endotracheal tube. The patient was uneventfully extubated several hours later. This is the first report of laryngospam and hypoxia associated with prehospital administration of intramuscular ketamine to a patient with excited delirium.     

Hypoglycemia Emergencies: Factors Associated with Prehospital Care,Transportation Status,Emergency Department Disposition,and Cost

Objectives: The objectives of this study were to evaluate demographic/clinical characteristics and treatment/transportation decisions by emergency medical services (EMS) for patients with hypoglycemia and link EMS activations to patient disposition, outcomes, and costs to the emergency medical system. This evaluation was to identify potential areas where improvements in prehospital healthcare could be made. Methods: This was a retrospective analysis of the National Emergency Medical Services Information System (NEMSIS) registry and three national surveys: Nationwide Emergency Department Sample (NEDS), National Hospital Ambulatory Medical Care Survey (NHAMCS), and Medical Expenditure Panel Survey (MEPS) from 2013, to examine care of hypoglycemia from the prehospital and the emergency department (ED) perspectives. Results: The study estimated 270,945 hypoglycemia EMS incidents from the NEMSIS registry. Treatments were consistent with national guidelines (i.e., oral glucose, intravenous [IV] dextrose, or glucagon), and patients were more likely to be transported to the ED if the incident was in a rural setting or they had other chief concerns related to the pulmonary or cardiovascular system. Use of IV dextrose decreased the likelihood of transportation. Approximately 43% of patients were not transported from the scene. Data from the NEDS survey estimated 258,831 ED admissions for hypoglycemia, and 41% arrived by ambulance. The median ambulance expenditure was $664?±?98. From the ED, 74% were released. The average ED charge that did not lead to hospital admission was $3106?±?86. Increased odds of overnight admission included infection and acute renal failure. Conclusions: EMS activations for hypoglycemia are sizeable and yet a considerable proportion of patients are not transported to or are discharged from the ED. Seemingly, these events resolved and were not medically complex. It is possible that implementation and appropriate use of EMS treat-and-release protocols along with utilizing programs to educate patients on hypoglycemia risk factors and emergency preparedness could partially reduce the burden of hypoglycemia to the healthcare system.     

Ketamine versus ketamine pluses atropine for pediatric sedation: A meta-analysis

Objectives

The application of atropine for pediatric sedation in the emergency department remains controversial. Our objective was to perform a comprehensive review of the literature and assess the clinical indexes in groups with and without atropine use.

Diagnostic accuracy of prehospital electrocardiograms interpreted remotely by emergency physicians in myocardial infarction patients

BackgroundPrehospital 12‑lead electrocardiogram (ECG) is the most widely used screening tool for recognition of ST-segment elevation myocardial infarction (STEMI). However, prehospital diagnosis of STEMI based solely on ECGs can be challenging.ObjectivesTo evaluate the ability of emergency department (ED) physicians to accurately interpret prehospital 12‑lead ECGs from a remote location.MethodsAll suspected prehospital STEMI patients who were transported by EMS and underwent angiography between 2006 and 2014 were included. We reviewed prehospital ECGs and grouped them based on: 1) presence or absence of a culprit artery lesion following angiography; and 2) whether they met the 3rd Universal Definition of Myocardial Infarction. We also described characteristics of ECGs that were misinterpreted by ED physicians.ResultsA total of 625 suspected STEMI cases were reviewed. Following angiography, 94% (590/625) of patients were found having a culprit artery lesion, while 6% (35/625) did not. Among these 35 patients, 24 had ECGs that mimicked STEMI criteria and 9 had non-ischemic signs. Upon ECG reinterpretation, 92% (577/625) had standard STEMI criteria while 8% (48/625) did not. Among these 48 patients, 35 had ischemic signs ECGs and 13 did not. Characteristics of misinterpreted ECGs included pericarditis, early repolarization, STE > 1 mm (1‑lead only), and negative T-wave.ConclusionsRemote interpretation of prehospital 12‑lead ECGs by ED physicians was a useful diagnostic tool in this EMS system. Even if the rate of ECG misinterpretation is low, there is still room for ED physicians operating from a remote location to improve their ability to accurately diagnose STEMI patients.     

Potential time savings by prehospital administration of activated charcoal

Objective. Activated charcoal (AC) has been proven useful in many toxic ingestions. Theoretically, administration of AC in the prehospital environment could save valuable time in the treatment of patients who have sustained potentially toxic oral ingestions. The purpose of this study was to determine the frequency of prehospital AC administration and to identify time savings that could potentially result from field AC administration.

Methods. Adult patients with a chief complaint of toxic ingestion who had complete emergency medical services (EMS) and emergency department (ED) records and no medical treatment (gastric emptying, AC administration) prior to EMS arrival were eligible for inclusion. Data obtained from EMS and ED records included time of EMS departure from the scene, time of EMS arrival at the ED, and time of administration of AC in the ED. Since most EMS agencies in this system do not insert gastric tubes, patients requiring gastric tube placement for administration of AC were excluded.

Results. Twenty-nine of 117 (24.8%) adult patients received oral AC with no other intervention. None of the 117 patients received AC in the prehospital setting. The EMS transport time for these patients ranged from 5 to 43 minutes (mean 16.2 ± 9.7 minutes). The delay from ED arrival to AC administration ranged from 5 to 94 minutes (mean 48.8 ± 24.1 minutes), and was more than 60 minutes for 14 (48.2%) of the patients. The total time interval from scene departure to ED AC administration ranged from 17 to 111 minutes (mean 65.0 ± 25.9 minutes). Conclusions. In a selected subset of patients who tolerate oral AC, prehospital administration of AC could result in earlier and potentially more efficacious AC therapy. Prospective study of the benefits and feasibility of prehospital AC administration is indicated.     

Adjunctive Atropine Is Unnecessary during Ketamine Sedation in Children

Background:  The prophylactic coadministration of atropine or other anticholinergics during dissociative sedation has historically been considered mandatory to mitigate ketamine-associated hypersalivation. Emergency physicians (EPs) are known to omit this adjunct, so a prospective study to describe the safety profile of this practice was initiated.
Objectives:  To quantify the magnitude of excessive salivation, describe interventions for hypersalivation, and describe any associated airway complications.
Methods:  In this prospective observational study of emergency department (ED) pediatric patients receiving dissociative sedation, treating physicians rated excessive salivation on a 100-mm visual analog scale and recorded the frequency and nature of airway complications and interventions for hypersalivation.
Results:  Of 1,090 ketamine sedations during the 3-year study period, 947 (86.9%) were performed without adjunctive atropine. Treating physicians assigned the majority (92%) of these subjects salivation visual analog scale ratings of 0 mm, i.e., "none," and only 1.3% of ratings were ≥ 50 mm. Transient airway complications occurred in 3.2%, with just one (brief desaturation) felt related to hypersalivation (incidence 0.11%, 95% confidence interval = 0.003% to 0.59%). Interventions for hypersalivation (most commonly suctioning) occurred in 4.2%, with no occurrences of assisted ventilation or intubation.
Conclusions:  When adjunctive atropine is omitted during ketamine sedation in children, excessive salivation is uncommon, and associated airway complications are rare. Anticholinergic prophylaxis is not routinely necessary in this setting.     

The feasibility of a regional cardiac arrest receiving system

BACKGROUND: Patients suffering out-of-hospital cardiac arrest (OOHCA) are generally transported to the closest ED, presumably to expedite a hospital level of care and improve the chances of return for spontaneous circulation (ROSC) or provide post-resuscitative care for patients with prehospital ROSC. As hospital-based therapies for survivors of OOHCA are identified, such as hypothermia and emergency primary coronary interventions (PCI), certain hospitals may be designated as cardiac arrest receiving facilities. The safety of bypassing non-designated facilities with such a regional system is not known. OBJECTIVES: To explore the potential ED contribution in OOHCA victims without prehospital ROSC and document the relationship between transport time and outcome in patients with prehospital ROSC. METHODS: This was a prospective, observational study conducted in a large, urban EMS system over an 18-month period. Data were collected using the Utstein template for OOHCA. The incidence of prehospital ROSC was calculated for patients who were declared dead on scene, transported but died in the ED, died in the hospital, and survived to hospital discharge. The relationship between transport time and survival was also explored for patients with prehospital ROSC. RESULTS: A total of 1141 cardiac arrest patients were enrolled over the 18-month period. A strong association between prehospital ROSC and final disposition was observed (chi-square test for trend p<0.001). Only two patients who survived to hospital discharge did not have prehospital ROSC. Mean transport times were not significantly different for patients with prehospital ROSC who were declared dead in the ED (8.3min), died following hospital admission (7.8min), and survived to hospital discharge (8.5min). Outcomes in patients with prehospital ROSC who had shorter (7min or less) versus longer transport times were similar, and receiver-operator curve analysis indicated no predictive ability of transport time with regard to survival to hospital admission (area under the curve=0.52). CONCLUSIONS: In this primarily urban EMS system, the vast majority of survivors from OOHCA are resuscitated in the field. A relationship between transport time and survival to hospital admission or discharge was not observed. This supports the feasibility of developing a regional cardiac arrest system with designated receiving facilities.     

Accuracy of Paramedic Broselow Tape Use in the Prehospital Setting

Introduction. Previous literature has documented that prehospital 12-lead electrocardiography (ECG) decreases the time to reperfusion in patients with an acute ST-segment elevation myocardial infarction (STEMI). Objective. To compare time to ECG, time to angioplasty suite (laboratory), andtime to reperfusion in emergency medical services (EMS) STEMI patients, who received care through three different processes. Methods. The setting was a large suburban community teaching hospital with emergency department (ED)-initiated single-page acute myocardial infarction (AMI) team activation for STEMI patients. The population was STEMI patients transported by EMS from January 2003 to October 2005. Not all EMS agencies had prehospital 12-lead ECG capability. Paramedics interpret andverbally report clinical assessment andECG findings via radio. The AMI team is activated at the discretion of the emergency physician 1) before patient arrival to the ED based on EMS assessment, 2) after ED evaluation with EMS ECG, or 3) after ED evaluation andED ECG. Time intervals were calculated from ED arrival. To assess the impact of interventions on performance targets, we also report the proportion of patients who arrived in laboratory within 60 minutes andreperfusion within 90 minutes of arrival. Parametric andnonparametric statistics are used for analysis. Results. During the study period, there were 164 STEMI patients transported by EMS; mean age was 66.1 years, and56% were male. Of these, 93 (56.7%) had an EMS ECG and31 (33%) had AMI team activation before ED arrival. Mean time to laboratory for all patients was 49.8 ± 34.4 minutes andtime to reperfusion was 93.2 +/? 34.5 min. Patients with prearrival activation were transported to laboratory sooner (mean, 24.3 vs. 53. 4 minutes; p < 0.001) andreceived reperfusion sooner than all other patients (mean, 70.4 vs. 96.3 minutes; p = 0.007). More prearrival activation patients met performance targets to laboratory (96.7% vs. 73.7%; p = 0.009) andreperfusion (85.2% vs. 51.0%; p = 0.003). There was no difference in time to laboratory or to reperfusion for patients who received EMS ECG but no prearrival activation compared with those who received EMS transport alone. Conclusions. A minority of patients with EMS ECGs had prearrival AMI team activation. EMS ECGs combined with systems that activate hospital resources, but not EMS ECGs alone, decrease time to laboratory andreperfusion.     

F EW E MERGENCY M EDICAL S ERVICES P ATIENTS WITH L OWER-EXTREMITY F RACTURES R ECEIVE P REHOSPITAL A NALGESIA

Previous literature has identified prehospital pain management as an important emergency medical services (EMS) function, and few patients transported by EMS with musculoskeletal injuries receive prehospital analgesia (PA). Objectives. 1) To describe the frequency with which EMS patients with lower-extremity and hip fracture receive prehospital and emergency department (ED) analgesia; 2) to describe EMS and patient factors that may affect administration of PA to these patients; and 3) to describe the time interval between EMS and ED medication administrations. Methods. This was a four-month (April to July 2000) retrospective study of patients with a final hospital diagnosis of hip or lower-extremity fracture who were transported by EMS to a single suburban community hospital. Data including patient demographics, fracture type, EMS response, and treatment characteristics were abstracted from review of EMS and ED records. Patients who had ankle fractures, had multiple traumatic injuries, were under the age of 18 years, or did not have fractures were excluded. Results. One hundred twenty-four patients met inclusion criteria. A basic life support (BLS)-only response was provided to 20 (16.0%). Another 38 (38.4%) received an advanced life support (ALS) response and were triaged to BLS transport. Of all the patients, 22 (18.3%) received PA. Patients who received PA were younger (64.0 vs. 77.3 years, p < 0.001) and more likely to have a lower-extremity fracture other than a hip fracture (31.8% vs. 10.7%, p < 0.004). Of all patients, 113 (91.1%) received ED analgesia. Patients received analgesia from EMS almost 2.0 hours sooner that in the ED (mean 28.4 ± 36 min vs. 146 ± 74 min after EMS scene arrival, p < 0.001). Conclusion. A minority of the study group received PA. Older patients and patients with hip fracture are less likely to receive PA. It is unclear whether current EMS system design may adversely impact administration of PA. Further work is needed to clarify whether patient need or EMS practice patterns result in low rates of PA.     

Successful Management of Excited Delirium Syndrome with Prehospital Ketamine: Two Case Examples

Abstract

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.     

Factors Associated with Prehospital Delay for Acute Stroke in Ulsan, Korea

Background: Early hospital presentation is critical in the treatment of acute ischemic stroke with thrombolysis. Objectives: The aim of this study was to investigate the factors associated with prehospital delay in acute ischemic stroke. Methods: Data were retrospectively collected over a 1-year period from 247 acute ischemic stroke patients who presented to the emergency department (ED) within 7 days after symptom onset. To investigate the factors associated with prehospital delay, sociodemographic data, initial symptoms, risk factor, National Institutes of Stroke Scale in the ED, and use of emergency medical services (EMS) were evaluated. Univariate and multivariate analysis were used to evaluate delay factors. Results: Of 247 patients (mean age 64.4 ± 12.6 years, 149 male patients), the non-delay group (≤ 2 h after symptom onset) included 45 patients (mean age 60.0 ± 13.1 years, 31 male patients) and the delay group (> 2 h after symptom onset) included 202 patients (mean age 65.4 ± 12.3 years, 118 male patients). Advanced age (odds ratio [OR] 1.056, 95% confidence interval [CI] 1.024-1.089), no consciousness disturbance at symptom onset (OR 2.938, 95% CI 1.066-8.104), presentation to ED by self (OR 3.826, 95% CI 1.580-9.624), referral from other hospital (OR 16.787, 95% CI 5.445-51.750), and worsened symptoms at the ED compared to symptom onset (OR 7.708, 95% CI 1.557-38.151) were associated with a prehospital delay. Conclusion: Elderly patients with progressive symptom worsening had delayed arrival, but those who used EMS or had disturbed consciousness at symptom onset had early arrival.     

Validation of field assessment stroke triage for emergency destination for prehospital use in a rural EMS system

BackgroundField Assessment Stroke Triage for Emergency Destination (FAST-ED) is a simple and accurate prehospital stroke severity scale that has been shown to have comparable accuracy to the gold standard National Institutes of Health Stroke Scale (NIHSS) but requires further field validation for use by emergency medical services (EMS), particularly in rural systems. FAST-ED scores ≥4 are considered high probability for large vessel occlusion (LVO) strokes, while scores <4 are low to moderate probability for LVO. The objective of this study was to assess inter-rater reliability of the EMS FAST-ED (EMS) score to the emergency department FAST-ED (ED-MD) scores.MethodsEMS calculated FAST-ED scores prior to transport to the emergency department (ED) on patients with a positive prehospital stroke screen. EDMD calculated FAST-ED scores for the same patients upon arrival to the ED. Interrater reliability and test characteristics were calculated.ResultsA total of 95 patients were included in this study and 14 were subsequently diagnosed with an LVO. EMS assigned 34 patients (35.8%) a FAST-ED score of ≥4. EDMD assigned 25 patients (26.3%) a FAST-ED score of ≥4. Using the clinical cut-points of FAST-ED scores <4 and ≥ 4, a linearly weighted Cohen's kappa coefficient showed moderate interrater reliability when comparing EMS and EDMD scores (k_w 0.44, 95% CI 0.25–0.63). At ≥4, EMS FAST-ED scores had a sensitivity 0.48, specificity 0.75, PPV 0.62, NPV 0.62 for predicting an LVO, while EDMD FAST-ED scores had a sensitivity 0.36, specificity 0.82, PPV 0.64, NPV 0.60. Comparable receiver operator curve area under the curve values were obtained.ConclusionsEMS and EDMD FAST-ED scores were moderately comparable in a rural EMS system. Similar NPVs compared to EDMD suggest the use of FAST-ED as an appropriate screening tool for EMS to predict the probability of LVO in the prehospital setting and make destination determinations regarding primary transport to a thrombectomy-capable stroke center.     

Few emergency medical services patients with lower-extremity fractures receive prehospital analgesia

Previous literature has identified prehospital pain management as an important emergency medical services (EMS) function, and few patients transported by EMS with musculoskeletal injuries receive prehospital analgesia (PA). Objectives. 1) To describe the frequency with which EMS patients with lower-extremity and hip fracture receive prehospital and emergency department (ED) analgesia; 2) to describe EMS and patient factors that may affect administration of PA to these patients; and 3) to describe the time interval between EMS and ED medication administrations. Methods. This was a four-month (April to July 2000) retrospective study of patients with a final hospital diagnosis of hip or lower-extremity fracture who were transported by EMS to a single suburban community hospital. Data including patient demographics, fracture type, EMS response, and treatment characteristics were abstracted from review of EMS and ED records. Patients who had ankle fractures, had multiple traumatic injuries, were under the age of 18 years, or did not have fractures were excluded. Results. One hundred twenty-four patients met inclusion criteria. A basic life support (BLS)-only response was provided to 20 (16.0%). Another 38 (38.4%) received an advanced life support (ALS) response and were triaged to BLS transport. Of all the patients, 22 (18.3%) received PA. Patients who received PA were younger (64.0 vs. 77.3 years, p < 0.001) and more likely to have a lower-extremity fracture other than a hip fracture (31.8% vs. 10.7%, p < 0.004). Of all patients, 113 (91.1%) received ED analgesia. Patients received analgesia from EMS almost 2.0 hours sooner that in the ED (mean 28.4 ± 36 min vs. 146 ± 74 min after EMS scene arrival, p < 0.001). Conclusion. A minority of the study group received PA. Older patients and patients with hip fracture are less likely to receive PA. It is unclear whether current EMS system design may adversely impact administration of PA. Further work is needed to clarify whether patient need or EMS practice patterns result in low rates of PA. PREHOSPITAL EMERGENCY CARE 2002;6:406-410