Medic and Portable Pulse Oximeter Respiratory Rate Measurement Comparison to Waveform Capnography: A Prospective, Observational Study.

BACKGROUND: The second leading cause of preventable battlefield death involves airway management. Tactical combat casualty care (TCCC) guidelines emphasize combat casualty airway, breathing and respiratory evaluation, including respiratory rate (RR) measurement. The current standard of practice for the US Army medics is to measure the RR by manual counting. Manual counting methods are operator-dependent, and medics face situational stressors limiting accurate measurement of RR in combat settings. To date, no published studies evaluate alternate methods of RR measurement by medics. The purpose of this study is to compare RR assessment by medics against waveform capnography and commercial finger pulse oximeters with continuous plethysmography. MATERIALS AND METHODS: We conducted a prospective, observational study to compare Army medic RR assessments against plethysmography and waveform capnography RR. Assessments were performed prior to and following exertion at 30 and 60 seconds with both the pulse oximeter (NSN 6515-01-655-9412) and defibrillator monitor (NSN 6515-01-607-8629), followed by end-user surveys. RESULTS: Of the 40 medics enrolled over a 4-month period, most were male (85%), and reported between less than 5 years of military and medical experience. The mean manual RR reported by medics at rest did not significantly differ from waveform capnography (14.05 versus 13.98, p is equal to 0.523); however, mean manual RR reported by medics on post-exertional subjects was significantly lower than waveform capnography (25.62 versus 29.77, p is less than 0.001). Time to medic-obtained RR was slower than the pulse oximeter (NSN 6515-01-655-9412) both at rest (-7.37 seconds, p is less than 0.001) and at exertion (-6.50 seconds, p is less than 0.001). While the mean difference in RR between the pulse oximeter (NSN 6515-01-655-9412) and waveform capnography in models at rest at 30 seconds was statistically significant (-1.38, p is less than 0.001). There was no overall statistically significant differences in RR between the pulse oximeter (NSN 6515-01-655-9412) and waveform capnography in models at exertion at 30 seconds and at rest and exertion at 60 seconds. CONCLUSION: Resting RR measurement did not differ significantly; however, medic-obtained RR considerably deviated from both pulse oximeters and waveform capnography at elevated rates. Existing commercial pulse oximeters with RR plethysmography do not differ significantly from waveform capnography and should be investigated further for consideration in fielding across the force for RR assessment.

Can D-Dimer in Low-Risk Patients Exclude Aortic Dissection in the Emergency Department?

BACKGROUND: Aortic dissection (AD) is a challenging diagnosis associated with severe mortality. However, acute AD is a rare clinical entity and can be overevaluated in the emergency department. D-dimer, both alone and in combination with the Aortic Dissection Detection Risk Score (ADD-RS), has been studied as a tool to evaluate for AD. CLINICAL QUESTION: Can a negative D-dimer in low-risk patients exclude AD in the emergency department? EVIDENCE REVIEW: Retrieved studies included three systematic review and meta-analyses and two prospective cohort studies. D-dimer was found to be highly sensitive for acute AD, with a sensitivity of 98.0%. The ADD-RS was also highly sensitive (95.7%) for AD. Two meta-analyses reported a combination of a negative D-dimer and ADD-RS < 1 to have a pooled sensitivity of 99.9% and 100% for acute aortic syndrome. CONCLUSIONS: Neither D-dimer nor the ADD-RS alone provides adequate sensitivity to exclude acute AD. However, a negative D-dimer combined with an ADD-RS < 1 is likely sufficient to rule out AD. Even with these findings, physicians must place clinical judgment above laboratory testing or scoring systems when deciding whether to pursue a diagnosis of acute AD.

Comparing two doses of intramuscular ketorolac for treatment of acute musculoskeletal pain in a military emergency department.

STUDY OBJECTIVE: The goal of the study was to assess a low-dose versus a high-dose of intramuscular (IM) ketorolac for non-inferiority in adults with acute MSK pain in an emergency department (ED). METHODS: This was a single-blinded, randomized controlled, non-inferiority trial of adults presenting to an ED with a chief complaint of acute MSK pain. Patients were randomized to either a 15 mg or a 60 mg IM ketorolac dose. The primary outcome was the mean difference of change in pain from baseline to 60-min between the two groups as reported on a 100-mm (mm) visual analog scale (VAS). Secondary outcomes included the mean difference of change in VAS scores at 30-min and the incidence of reported adverse effects associated with the administration of ketorolac. RESULTS: One hundred ten patients were randomized with 55 in each group. The mean difference in pain between groups at 60-min (0.2 mm [95% CI -8.5-8.7]; p = .98) and 30 min (-1.7 mm [95% CI -8.5-5.1; p = .63) was less than the predetermined non-inferiority margin of 13 mm. There were no major adverse effects reported. Minor adverse effects were more frequent in the 60 mg group (n = 9; 16.4% vs. n = 1; 1.8%; p = .016) with burning at the injection site being the most commonly reported. CONCLUSIONS: A 15 mg dose of IM ketorolac was found to be non-inferior to a 60 mg dose for acute MSK pain in adults presenting to the ED. Discontinuing the practice of ordering 60 mg doses of IM ketorolac in place of a lower dose for acute MSK pain should be considered.

Oncologic Emergencies: Palliative Care in the Emergency Department Setting.

BACKGROUND: Palliative care is an essential component of emergency medicine, as many patients with terminal illness will present to the emergency department (ED) for symptomatic management at the end of life (EOL). OBJECTIVE: This narrative review evaluates palliative care in the ED, with a focus on the literature behind management of EOL symptoms, especially dyspnea and cancer-related pain. DISCUSSION: As the population ages, increasing numbers of patients present to the ED with severe EOL symptoms. An understanding of the role of palliative care in the ED is crucial to effectively communicating with these patients to determine their goals and provide medical care in line with their wishes. Beneficence, nonmaleficence, and patient autonomy are essential components of palliative care. Patients without medical decision-making capacity may have an advance directive, do not resuscitate or do not intubate order, or Portable Medical Orders for Life-Sustaining Treatment available to assist clinicians. Effective and empathetic communication with patients and families is vital to EOL care discussions. Two of the most common and distressing symptoms at the EOL are dyspnea and pain. The most effective treatment of EOL dyspnea is opioids, with literature showing little efficacy for other therapies. The most effective treatment for cancer-related pain is opioids, with expeditious pain control achievable with a rapid fentanyl titration. It is also important to address nausea, vomiting, and secretions, as these are common at the EOL. CONCLUSIONS: Emergency clinicians play a vital role in EOL patient care. Clear, empathetic communication and treatment of EOL symptoms are essential.

A 61-year-old Female with Right Upper Abdominal Pain.

CASE PRESENTATION: A 61-year-old female presented to the emergency department with right upper quadrant abdominal pain following a cholecystectomy 18 days prior. Computed tomography (CT) of her abdomen demonstrated a large abscess in her post-hepatic fossa. She was admitted to the general surgery service and received an image-guided percutaneous drain placement with interventional radiology with immediate return of purulent material. She was discharged home after a three-day hospital course with outpatient antibiotics and follow-up. DISCUSSION: Patients may have multiple complications following cholecystectomy, including infection, bleeding, biliary injury, bowel injury, or dropped stone. The emergency clinician must consider cholecystectomy complications including gallbladder fossa abscess in patients presenting with abdominal pain in the days to weeks following cholecystectomy, especially if they present with signs of sepsis. Critical actions include obtaining CT and/or ultrasonography, initiating broad spectrum antibiotics, and obtaining definitive source control by either surgery or interventional radiology.

Large Vessel Occlusion Stroke Secondary to Acute Aortic Dissection.

Aortic dissection carries a high mortality of up to 40% at the time of initial dissection and an additional 1% per hour the dissection is untreated. Patients with acute aortic dissection most commonly present with chest or back pain. Less frequently, it manifests without pain with predominant neurologic symptoms secondary to an acute stroke. We present the case of a 53-year-old male presenting with acute onset aphasia and right-sided weakness. Incidentally, CT angiography of his neck revealed a carotid artery dissection, which was found an extension of a Stanford type A acute aortic dissection resulting in a large vessel occlusion stroke. The patient's concomitant pathologies resulted in uncertainty as to the priority of management between the interventional neurology and cardiothoracic surgery services, ultimately resulting in the transfer of the patient to an aorta specialist at an outside facility. This case highlights several areas of difficulty in the management of patients with presenting with both large vessel occlusion stroke and acute aortic dissection and the need for consideration of acute aortic dissection in patients presenting with symptoms consistent with large vessel occlusion stroke. Optimal blood pressure control is unknown, as is the ideal timing of aortic repair and the potential for endovascular therapy for large vessel occlusion stroke in the setting of acute aortic dissection. Emergency physicians must rapidly engage with neurology, interventional neurology, and cardiothoracic surgery to determine appropriate interventions and timing of operative repair. The emergency physician must consider acute aortic dissection in patients presenting with signs and symptoms concerning for large vessel occlusion stroke, even if they have no complaint of chest pain, as administration of thrombolytics in these patients may be deadly.

An emergency medicine-focused review of malignant otitis externa.

INTRODUCTION: Malignant otitis externa (MOE) is a progressive infection of the external auditory canal (EAC). This disease is rare but has severe morbidity and mortality. OBJECTIVE: This narrative review provides an overview of malignant otitis externa for emergency clinicians. DISCUSSION: MOE is an invasive external ear infection that spreads to the temporal bone and can further progress to affect intracranial structures. Complications of advanced MOE include cranial nerve involvement, most commonly the facial nerve, and intracranial infections such as abscess and meningitis. The most common causative agent of MOE is Pseudomonas aeruginosa, but others include methicillin-resistant Staphylococcus aureus and fungi. Major risk factors for MOE include diabetes mellitus, immunosuppression, and advanced age. Red flags for MOE include severe otalgia (pain out of proportion to exam) or severe otorrhea, neurologic deficits (especially facial nerve involvement), previously diagnosed otitis externa not responsive to therapy, and patients with major risk factors for MOE. Examination may show purulent otorrhea or granulation tissue in the EAC, and culture of EAC drainage should be performed. Diagnosis is aided by computed tomography (CT) with intravenous contrast, which may demonstrate bony destruction of the temporal bone or skull base. When suspecting MOE, early consultation with an otolaryngologist is recommended and antibiotics with pseudomonal coverage are needed. Most patients with MOE will require admission to the hospital. CONCLUSIONS: MOE is a rare, yet deadly diagnosis that must be suspected when patients with immunocompromise, diabetes, or advanced age present with severe otalgia. Rapid diagnosis and treatment may prevent complications and improve outcomes.

55 year-old Female with Hematuria.

CASE PRESENTATION: A 55 year-old female presented to the emergency department with left sided abdominal pain and hematuria. Computed tomography scan of her abdomen and pelvis demonstrated a large left renal mass with extension into the left ureter, left renal vein, and inferior vena cava. She was admitted and treated for presumed renal cell carcinoma (RCC). DISCUSSION: RCC may present with abdominal or flank pain and hematuria, but more commonly presents with vague symptoms. RCC should be suspected in a patient presenting with hematuria and abdominal or flank pain, especially if vague symptoms such as fatigue or anorexia are also present.

A Case of Traumatic Aortic Transection Presenting With Hemorrhagic Shock.

BACKGROUND: Aortic transection, or aortic rupture, is a rare diagnosis in trauma patients and carries a high mortality. CASE REPORT: We present the case of a 61-year-old man presenting to a Level I trauma center after being struck by a motor vehicle, found to have an aortic transection. He was initially hypotensive and resuscitated with blood products due to concern for hemorrhagic shock. Aortic injury was suspected after chest x-ray study demonstrated a widened mediastinum. Traumatic thoracic aortic transection with pseudoaneurysm was diagnosed on computed tomography of the aorta, and the patient was taken to the operating room for thoracic endovascular repair of the aorta. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Diagnosis of aortic injury can be challenging, especially in trauma patients presenting with hypotension. Aortic injury must be suspected in patients presenting after a high-velocity mechanism injury. It is an uncommon cause of hemorrhagic shock in trauma patients and must be considered even if other traumatic injuries are identified, as it commonly occurs with other significant injuries. Although chest x-ray study can be useful, a negative chest x-ray study does not rule out aortic injury. Aortic injury is a time-sensitive diagnosis, and early identification is key to these patients surviving to receive definitive management in the operating room.

Emergency medicine misconceptions: Utility of routine coagulation panels in the emergency department setting.

BACKGROUND: Coagulation panels are ordered for a variety of conditions in the emergency department (ED). OBJECTIVE: This narrative review evaluates specific conditions for which a coagulation panel is commonly ordered but has limited utility in medical decision-making. DISCUSSION: Coagulation panels consist of partial thromboplastin time (PTT) or activated partial thromboplastin time (aPTT), prothrombin time (PT), and international normalized ratio (INR). These tests evaluate the coagulation pathway which leads to formation of a fibrin clot. The coagulation panel can monitor warfarin and heparin therapy, evaluate for vitamin K deficiency, evaluate for malnutrition or severe systemic disease, and assess hemostatic function in the setting of bleeding. The utility of coagulation testing in chest pain evaluation, routine perioperative assessment, prior to initiation of anticoagulation, and as screening for admitted patients is low, with little to no change in patient management based on results of these panels. Coagulation testing should be considered in systemically ill patients, those with a prior history of bleeding or family history of bleeding, patients on anticoagulation, or patients with active hemorrhage and signs of bleeding. Thromboelastography and rotational thromboelastometry offer more reliable measures of coagulation function. CONCLUSIONS: Little utility for coagulation assessment is present for the evaluation of chest pain, routine perioperative assessment, initiation of anticoagulation, and screening for admitted patients. However, coagulation panel assessment should be considered in patients with hemorrhage, patients on anticoagulation, and personal history or family history of bleeding.

An emergency medicine approach to troponin elevation due to causes other than occlusion myocardial infarction.

INTRODUCTION: Troponin is an integral component of the evaluation for acute coronary syndrome (ACS) and occlusion myocardial infarction (OMI). However, troponin may be elevated in conditions other than OMI. OBJECTIVE: This narrative review provides emergency clinicians with a focused evaluation of troponin elevation in patients with myocardial injury due to conditions other than OMI. DISCUSSION: ACS includes the diagnosis of myocardial infarction (MI), which incorporates assessment for elevated troponin. Troponin I and T are the most common biomarkers used in assessment of myocardial injury and may be released with myocyte injury and necrosis, myocyte apoptosis and cell turnover, and oxygen supply demand mismatch. Troponin elevation is a reflection of myocardial injury, and many conditions associated with critical illness may result in troponin elevation. These include cardiac and non-cardiac conditions. Cardiac conditions include heart failure, dysrhythmia, and dissection, while non-cardiac causes include pulmonary embolism, sepsis, stroke, and many others. Clinicians should consider the clinical context, patient symptoms, electrocardiogram, and ultrasound in their assessment of the patient with troponin elevation. In most cases, elevated troponin is a marker for poor outcomes including increased rates of mortality. CONCLUSIONS: Troponin can be elevated in many critical settings. The causes of troponin elevation include cardiac and non-cardiac conditions. Clinicians must consider the clinical context and other factors, as an inappropriate diagnosis of OMI may result in patient harm and misdiagnosis of another condition.

The Thunderclap Headache: Approach and Management in the Emergency Department.

BACKGROUND: A thunderclap headache (TCH) is a severe headache reaching at least 7 (out of 10) in intensity within 1 min of onset, and can be the presenting symptom of several conditions with potential for significant morbidity and mortality. OBJECTIVE OF THE REVIEW: This narrative review evaluates the various conditions that may present with TCH and proposes a diagnostic algorithm for patients with TCH. DISCUSSION: TCH is a symptom associated with several significant diseases. The most common diagnosed condition is subarachnoid hemorrhage (SAH). Other diagnoses include reversible cerebral vasoconstriction syndrome, cerebral venous thrombosis, cervical artery dissection, posterior reversible encephalopathy syndrome, spontaneous intracranial hypotension, and several others. Patients with TCH require history and physical examination, with a focus on the neurologic system, evaluating for these conditions, including SAH. Further testing often includes head computed tomography (CT) without contrast, CT angiography of the head and neck, and lumbar puncture. Evaluation must take into account history, examination, and the presence of any red flags or signs suggestive of a specific etiology. An algorithm is provided for guidance within this review incorporating these modalities. Management focuses on the specific diagnosis. If testing is negative for a serious condition and the patient improves, discharge home may be appropriate with follow-up. CONCLUSIONS: Patients presenting with TCH require diagnostic evaluation. History and examination are vital in assessing for risk factors for various conditions. Focused testing can assist with diagnosis, with management tailored to the specific diagnosis.

Clinical mimics: an emergency medicine focused review of pneumonia mimics.

Pneumonia is a common cause of morbidity and mortality in adults in the United States. While pneumonia classically presents with a fever, cough, and shortness of breath, the presentation can vary widely in adults. This review evaluates history and physical examination findings of pneumonia and several conditions that mimic pneumonia. Pneumonia is a potentially deadly disease. History and examination findings are variable in pneumonia, and many conditions mimic pneumonia. These conditions include pulmonary embolism, diffuse interstitial lung disease, endocarditis, vasculitis, diffuse alveolar hemorrhage, acute decompensated heart failure, tuberculosis, lung cancer, and acute respiratory distress syndrome. Emergency clinicians should assess the patient while resuscitation occurs. Early antibiotics and the diagnosis of pneumonia can improve outcomes. Key historical and physical examination findings may lead the clinician to consider other conditions that require immediate management. Using clinical evaluation and adjunctive imaging, these conditions can be diagnosed and treated. Knowledge of pneumonia mimics is vital for the care of patients with respiratory complaints. Pneumonia is common and may be deadly, and emergency clinicians must differentiate conditions that mimic pneumonia. Rapid evaluation and management may alleviate morbidity and mortality for each of these conditions. The history and physical examination, in addition to utilizing imaging modalities such as ultrasound and computed tomography, are vital in diagnosis of pneumonia mimics.

Prognosis of diffuse axonal injury with traumatic brain injury.

BACKGROUND: Determine the prognostic impact of magnetic resonance imaging (MRI)-defined diffuse axonal injury (DAI) after traumatic brain injury (TBI) on functional outcomes, quality of life, and 3-year mortality. METHODS: This retrospective single center cohort included adult trauma patients (age > 17 years) admitted from 2006 to 2012 with TBI. Inclusion criteria were positive head computed tomography with brain MRI within 2 weeks of admission. Exclusion criteria included penetrating TBI or prior neurologic condition. Separate ordinal logistic models assessed DAI's prognostic value for the following scores: (1) hospital-discharge Functional Independence Measure, (2) long-term Glasgow Outcome Scale-Extended, and (3) long-term Quality of Life after Brain Injury-Overall Scale. Cox proportional hazards modeling assessed DAI's prognostic value for 3-year survival. Covariates included age, sex, race, insurance status, Injury Severity Score, admission Glasgow Coma Scale Score, Marshall Head computed tomography Class, clinical DAI on MRI (Y/N), research-level anatomic DAI Grades I-III (I, cortical; II, corpus callosum; III, brainstem), ventilator days, time to follow commands, and time to long-term follow-up (for logistic models). RESULTS: Eligibility criteria was met by 311 patients, who had a median age of 40 years (interquartile range [IQR], 23-57 years), Injury Severity Score of 29 (IQR, 22-38), intensive care unit stay of 6 days (IQR, 2-11 days), and follow-up of 5 years (IQR, 3-6 years). Clinical DAI was present on 47% of MRIs. Among 300 readable MRIs, 56% of MRIs had anatomic DAI (25% Grade I, 18% Grade II, 13% Grade III). On regression, only clinical (not anatomic) DAI was predictive of a lower Functional Independence Measure score (odds ratio, 2.5; 95% confidence interval, 1.28-4.76], p = 0.007). Neither clinical nor anatomic DAI were related to survival, Glasgow Outcome Scale-Extended, or Quality of Life after Brain Injury-Overall Scale scores. CONCLUSION: In this longitudinal cohort, clinical evidence of DAI on MRI may only be useful for predicting short-term in-hospital functional outcome. Given no association of DAI and long-term TBI outcomes, providers should be cautious in attributing DAI to future neurologic function, quality of life, and/or survival. LEVEL OF EVIDENCE: Epidemiological, level III; Therapeutic, level IV.

Emergency Medicine Evaluation of Community-Acquired Pneumonia: History, Examination, Imaging and Laboratory Assessment, and Risk Scores.

BACKGROUND: Pneumonia is a common infection, accounting for approximately one million hospitalizations in the United States annually. This potentially life-threatening disease is commonly diagnosed based on history, physical examination, and chest radiograph. OBJECTIVE: To investigate emergency medicine evaluation of community-acquired pneumonia including history, physical examination, imaging, and the use of risk scores in patient assessment. DISCUSSION: Pneumonia is the number one cause of death from infectious disease. The condition is broken into several categories, the most common being community-acquired pneumonia. Diagnosis centers on history, physical examination, and chest radiograph. However, all are unreliable when used alone, and misdiagnosis occurs in up to one-third of patients. Chest radiograph has a sensitivity of 46-77%, and biomarkers including white blood cell count, procalcitonin, and C-reactive protein provide little benefit in diagnosis. Biomarkers may assist admitting teams, but require further study for use in the emergency department. Ultrasound has shown utility in correctly identifying pneumonia. Clinical gestalt demonstrates greater ability to diagnose pneumonia. Clinical scores including Pneumonia Severity Index (PSI); Confusion, blood Urea nitrogen, Respiratory rate, Blood pressure, age 65 score (CURB-65); and several others may be helpful for disposition, but should supplement, not replace, clinical judgment. Patient socioeconomic status must be considered in disposition decisions. CONCLUSION: The diagnosis of pneumonia requires clinical gestalt using a combination of history and physical examination. Chest radiograph may be negative, particularly in patients presenting early in disease course and elderly patients. Clinical scores can supplement clinical gestalt and assist in disposition when used appropriately.

The emergency medicine management of severe alcohol withdrawal.

INTRODUCTION: Alcohol use is widespread, and withdrawal symptoms are common after decreased alcohol intake. Severe alcohol withdrawal may manifest with delirium tremens, and new therapies may assist in management of this life-threatening condition. OBJECTIVE: To provide an evidence-based review of the emergency medicine management of alcohol withdrawal and delirium tremens. DISCUSSION: The underlying pathophysiology of alcohol withdrawal syndrome (AWS) is central nervous system hyperexcitation. Stages of withdrawal include initial withdrawal symptoms, hallucinations, seizures, and delirium tremens. Management focuses on early diagnosis, resuscitation, and providing medications with gamma-aminobutyric acid (GABA) receptor activity. Benzodiazepines with symptom-triggered therapy have been the predominant medication class utilized and should remain the first treatment option with rapid escalation of dosing. Treatment resistant withdrawal warrants the use of phenobarbital or propofol, both demonstrating efficacy in management. Propofol can be used as an induction agent to decrease the effects of withdrawal. Dexmedetomidine does not address the underlying pathophysiology but may reduce the need for intubation. Ketamine requires further study. Overall, benzodiazepines remain the cornerstone of treatment. Outpatient management of patients with minimal symptoms is possible. CONCLUSIONS: Alcohol withdrawal syndrome can result in significant morbidity and mortality. Physicians must rapidly diagnose these conditions while evaluating for other diseases. Benzodiazepines are the predominant medication class utilized, with adjunctive treatments including propofol or phenobarbital in patients with withdrawal resistant to benzodiazepines. Dexmedetomidine and ketamine require further study.