Factors Affecting Interfacility Transport Intervals in Stroke Patients Transferred for Endovascular Therapy.

OBJECTIVE: To describe interfacility transfer (IFT) intervals, transfer vehicle type, and levels of care in patients with large vessel occlusion (LVO) strokes transferred for emergent endovascular therapy (EVT). METHODS: We included all patients transferred by a single IFT agency in the state of Indiana from July 1, 2018 to December 1, 2020 to a comprehensive stroke center in Indianapolis for emergent EVT. Data were collected from the transfer center electronic medical records and matched to IFT and receiving hospital data. RESULTS: Two hundred eighty-eight patients were included, of which 150 (52.0%) received EVT. The median call-to-needle interval (from call to the transfer center to EVT needle puncture) was 155.5 minutes (IQR 135.8-195.3). The median resource activation interval (call to the transfer center to IFT deployment) was 16 minutes (IQR 10-27 minutes); the median IFT response interval (call to IFT to arrival of the transferring unit) was 34 minutes (IQR 25-43 minutes); the median pre-transfer interval (call to the transfer center until departure from the sending hospital) was 60.4 minutes (IQR 47.1-72.6); and the median sending hospital interval at bedside was 25 minutes (IQR 20-30 minutes). Most patients (197, 68.4%) were sent via critical care rotor. Only 61 (21.2%) required interventions other than tissue plasminogen administration, such as titration of actively transfusing medications (e.g., nicardipine, propofol) (37 of 61, 59.7%), or intubation or ventilator management (25 of 61, 40.3%). Patients sent via critical care rotor had longer sending hospital intervals (26 minutes, IQR 22-32, vs 19 minutes, IQR 16-25; p < 0.001) but shorter transfer intervals than those sent via critical care ground. CONCLUSIONS: At longer distances, rotor transport saved significant time specifically in the total IFT interval of patients with LVO strokes. Emphasizing processes to reduce the resource activation interval and the sending hospital interval may help reduce the overall time-to-EVT.

A Review of Bicarbonate Use in Common Clinical Scenarios.

BACKGROUND: The use of sodium bicarbonate to treat metabolic acidosis is intuitive, yet data suggest that not all patients benefit from this therapy. OBJECTIVE: In this narrative review, we describe the physiology behind commonly encountered nontoxicologic causes of metabolic acidosis, highlight potential harm from the indiscriminate administration of sodium bicarbonate in certain scenarios, and provide evidence-based recommendations to assist emergency physicians in the rational use of sodium bicarbonate. DISCUSSION: Sodium bicarbonate can be administered as a hypertonic push, as a resuscitation fluid, or as an infusion. Lactic acidosis and cardiac arrest are two common scenarios where there is limited benefit to routine use of sodium bicarbonate, although certain circumstances, such as patients with concomitant acute kidney injury and lactic acidosis may benefit from sodium bicarbonate. Patients with cardiac arrest secondary to sodium channel blockade or hyperkalemia also benefit from sodium bicarbonate therapy. Recent data suggest that the use of sodium bicarbonate in diabetic ketoacidosis does not confer improved patient outcomes and may cause harm in pediatric patients. Available evidence suggests that alkalinization of urine in rhabdomyolysis does not improve patient-centered outcomes. Finally, patients with a nongap acidosis benefit from sodium bicarbonate supplementation. CONCLUSIONS: Empiric use of sodium bicarbonate in patients with nontoxicologic causes of metabolic acidosis is not warranted and likely does not improve patient-centered outcomes, except in select scenarios. Emergency physicians should reserve use of this medication to conditions with clear benefit to patients.

Dispelling myths and misconceptions about the treatment of acute hyperkalemia.

Hyperkalemia represents a widespread and potentially lethal condition that affects millions of people across their lives. Despite the prevalence and severity of the condition, there are no consensus guidelines on the treatment of hyperkalemia or even a standard definition. Herein, we provide a succinct review of what we believe to be the most significant misconceptions encountered in the emergency care of hyperkalemia, examine current available literature, and discuss practical points on several modalities of hyperkalemia treatment. Additionally, we review the pathophysiology of the electrocardiographic effects of hyperkalemia and how intravenous calcium preparations can antagonize these effects. We conclude each section with recommendations to aid emergency physicians in making safe and efficacious choices for the treatment of acute hyperkalemia.

Validation of the NUE Rule to Predict Futile Resuscitation of Out-of-Hospital Cardiac Arrest.

AIM: We validated the NUE rule, using three criteria (Non-shockable initial rhythm, Unwitnessed arrest, Eighty years or older) to predict futile resuscitation of patients with out-of-hospital cardiac arrest (OHCA). METHODS: We performed a retrospective cohort analysis of all recorded OHCA in Marion County, Indiana, from January 1, 2014 to December 31, 2019. We described patient, arrest, and emergency medical services (EMS) response characteristics, and assessed the performance of the NUE rule in identifying patients unlikely to survive to hospital discharge. RESULTS: From 2014 to 2019, EMS responded to 4370 patients who sustained OHCA. We excluded 329 (7.5%) patients with incomplete data. Median patient age was 62 years (IQR 49 - 73), 1599 (39.6%) patients were female, and 1728 (42.8%) arrests were witnessed. The NUE rule identified 290 (7.2%) arrests, of whom none survived to hospital discharge. CONCLUSION: In external validation, the NUE rule (Non-shockable initial rhythm, Unwitnessed arrest, Eighty years or older) correctly identified 7.2% of OHCA patients unlikely to survive to hospital discharge. The NUE rule could be used in EMS protocols and policies to identify OHCA patients very unlikely to benefit from aggressive resuscitation.

Resuscitating Resuscitation: Advanced Therapies for Resistant Ventricular Dysrhythmias.

BACKGROUND: More than 640,000 combined in-hospital and out-of-hospital cardiac arrests occur annually in the United States. However, survival rates and meaningful neurologic recovery remain poor. Although "shockable" rhythms (i.e., ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT)) have the best outcomes, many of these ventricular dysrhythmias fail to return to a perfusing rhythm (resistant VF/VT), or recur shortly after they are resolved (recurrent VF/VT). OBJECTIVE: This review discusses 4 emerging therapies in the emergency department for treating these resistant or recurrent ventricular dysrhythmias: beta-blocker therapy, dual simultaneous external defibrillation, stellate ganglion blockade, and extracorporeal cardiopulmonary resuscitation. We discuss the underlying physiology of each therapy, review relevant literature, describe when these approaches should be considered, and provide evidence-based recommendations for these techniques. DISCUSSION: Esmolol may mitigate some of epinephrine's negative effects when used during resuscitation, improving both postresuscitation cardiac function and long-term survival. Dual simultaneous external defibrillation targets the region of the heart where ventricular fibrillation typically resumes and may apply a more efficient defibrillation across the heart, leading to higher rates of successful defibrillation. Stellate ganglion blocks, recently described in the emergency medicine literature, have been used to treat patients with recurrent VF/VT, resulting in significant dysrhythmia suppression. Finally, extracorporeal cardiopulmonary resuscitation is used to provide cardiopulmonary support while clinicians correct reversible causes of arrest, potentially resulting in improved survival and good neurologic functional outcomes. CONCLUSION: These emerging therapies do not represent standard practice; however, they may be considered in the appropriate clinical scenario when standard therapies are exhausted without success.

Demystifying Lactate in the Emergency Department.

The role of lactic acid and its conjugate base, lactate, has evolved during the past decade in the care of patients in the emergency department (ED). A recent national sepsis quality measure has led to increased use of serum lactate in the ED, but many causes for hyperlactatemia exist outside of sepsis. We provide a review of the biology of lactate production and metabolism, the many causes of hyperlactatemia, and evidence on its use as a marker in prognosis and resuscitation. Additionally, we review the evolving role of lactate in sepsis care. We provide recommendations to aid lactate interpretation in the ED and highlight areas for future research.

An Urban 9-1-1 System's Experience with Left Ventricular Assist Device Patients.

Background: Left ventricular assist devices (LVADs) are used with increasing frequency and left in place for longer periods of time. Prior publications have focused on the mechanics of troubleshooting the device itself. We aim to describe the epidemiology of LVAD patient presentations to emergency medical services (EMS), prehospital assessments and interventions, and hospital outcomes. Methods: This is a retrospective chart review of known LVAD patients that belong to a single academic center's heart failure program who activated the 9-1-1 system and were transported by an urban EMS system to one of the center's 2 emergency departments between January 2012 and December 2015. Identifying demographics were used to query the electronic medical record of the responding city fire agency and contracted transporting ambulance service. Two reviewers abstracted prehospital chief complaint, vital signs, assessments, and interventions. Emergency department and hospital outcomes were retrieved separately. Results: From January 2012 to December 2015, 15 LVAD patients were transported 16 times. The most common prehospital chief complaint was weakness (7/16), followed by chest pain (3/16). Of the 7 patients presenting with weakness, one was diagnosed with a stroke in the emergency department. Another patient was diagnosed with subarachnoid hemorrhage and expired during hospital admission. This was the only death in the cohort. The most common hospital diagnosis was GI bleed (3/16). The overall admission rate was 87.5% (14/16). Conclusions: EMS interactions with LVAD patients are infrequent but have high rates of admission and incidence of life-threatening diagnoses. The most common prehospital presenting symptoms were weakness and chest pain, and most prehospital interactions did not require LVAD-specific interventions. In addition to acquiring technical knowledge regarding LVADs, EMS providers should be aware of non-device-related complications including intracranial and GI bleeding and take this into account during their assessment.

The DAGMAR Score: D-dimer assay-guided moderation of adjusted risk. Improving specificity of the D-dimer for pulmonary embolism.

We generated a novel scoring system to improve the test characteristics of D-dimer in patients with suspected PE (pulmonary emboli). Electronic Medical Record data were retrospectively reviewed on Emergency Department (ED) patients 18 years or older for whom a D-dimer and imaging were ordered between June 4, 2012 and March 30, 2016. Symptoms (dyspnea, unilateral leg swelling, hemoptysis), age, vital signs, medical history (cancer, recent surgery, medications, history of deep vein thrombosis or PE, COPD, smoking), laboratory values (quantitative D-dimer, platelets, and mean platelet volume (MPV)), and imaging results (CT, VQ) were collected. Points were designated to factors that were significant in two multiple regression analyses, for PE or positive D-dimer. Points predictive of PE were designated positive values and points predictive of positive D-dimer, irrespective of presence of PE, were designated negative values. The DAGMAR (D-dimer Assay-Guided Moderation of Adjusted Risk) score was developed using age and platelet adjustment and points for factors associated with PE and elevated D-dimer. Of 8486 visits reviewed, 3523 were unique visits with imaging, yielding 2253 (26.5%) positive D-dimers. 3501 CT scans and 156 VQ scans were completed, detecting 198 PE. In our cohort, a DAGMAR Score < 2 equated to overall PE risk < 1.2%. Specificity improved (38% to 59%) without compromising sensitivity (94% to 96%). Use of the DAGMAR Score would have reduced CT scans from 2253 to 1556 and lead to fewer false negative results. By considering factors that affect D-dimer and also PE, we improved specificity without compromising sensitivity.

Use of the d-dimer for Detecting Pulmonary Embolism in the Emergency Department.

BACKGROUND: Assessment for pulmonary embolism (PE) in the emergency department (ED) remains complex, involving clinical decision tools, blood tests, and imaging. OBJECTIVE: Our objective was to examine the test characteristics of the high-sensitivity d-dimer for the diagnosis of PE at our institution and evaluate use of the d-dimer and factors associated with a falsely elevated d-dimer. METHODS: We retrospectively collected data on adult patients evaluated with a d-dimer and computed tomography (CT) pulmonary angiogram or ventilation perfusion scan at two EDs between June 4, 2012 and March 30, 2016. We collected symptoms (dyspnea, unilateral leg swelling, hemoptysis), vital signs, and medical and social history (cancer, recent surgery, medications, history of deep vein thrombosis or PE, chronic obstructive pulmonary disease, smoking). We calculated test characteristics, including sensitivity, specificity, and likelihood ratios for the assay using conventional threshold and with age adjustment, and performed a univariate analysis. RESULTS: We found 3523 unique visits with d-dimer and imaging, detecting 198 PE. Imaging was pursued on 1270 patients with negative d-dimers, revealing 9 false negatives, and d-dimer was sent on 596 patients for whom negative Pulmonary Embolism Rule-Out Criteria (PERC) were documented with 2% subsequent radiographic detection of PE. The d-dimer showed a sensitivity of 95.7% (95% confidence interval [CI] 91-98%), specificity of 40.0% (95% CI 38-42%), negative likelihood ratio of 0.11 (95% CI 0.06-0.21), and positive likelihood ratio of 1.59 (95% CI 1.53-1.66) for the radiographic detection of PE. With age adjustment, 347 of the 2253 CT scans that were pursued in patients older than 50 years with an elevated d-dimer could have been avoided without missing any additional PE. Many risk factors, such as age, history of PE, recent surgery, shortness of breath, tachycardia and hypoxia, elevated the d-dimer, regardless of the presence of PE. CONCLUSIONS: Many patients with negative d-dimer and PERC still received imaging. Our data support the use of age adjustment, and perhaps adjustment for other factors seen in patients evaluated for PE.

The "Flipped Classroom" Model for Teaching in the Intensive Care Unit.

INTRODUCTION: The intensive care unit (ICU) is a dynamic and complex learning environment. The wide range in trainee's experience, specialty training, fluctuations in patient acuity and volume, limitations in trainee duty hours, and additional responsibilities of the faculty contribute to the challenge in providing a consistent experience with traditional educational strategies. The "flipped classroom" is an educational model with the potential to improve the learning environment. In this paradigm, students gain exposure to new material outside class and then use class time to assimilate the knowledge through problem-solving exercises or discussion. The rationale and pedagogical foundations for the flipped classroom are reviewed, practical considerations are discussed, and an example of successful implementation is provided. METHODS: An education curriculum was devised and evaluated prospectively for teaching point-of-care echocardiography to residents rotating in the surgical ICU. RESULTS: Preintervention and postintervention scores of knowledge, confidence, perceived usefulness, and likelihood of use the skills improved for each module. The quality of the experience was rated highly for each of the sessions. CONCLUSION: The flipped classroom education curriculum has many advantages. This pilot study was well received, and learners showed improvement in all areas evaluated, across several demographic subgroups and self-identified learning styles.

The Association of Age With Short-Term and Long-Term Mortality in Adults Admitted to the Intensive Care Unit.

BACKGROUND: Based on the current literature, it is unclear whether advanced age itself leads to higher mortality in critically ill patients or whether it is due to the greater number of comorbidities in the elderly patients. We hypothesized that increasing age would increase the odds of short-term and long-term mortality after adjusting for baseline comorbidities in intensive care unit (ICU) patients. METHODS: We performed a retrospective cohort study of 57 160 adults admitted to any ICU over 5 years at 2 academic tertiary care centers. Patients were divided into age-groups, 18 to 39, 40 to 59, 60 to 79, and ≥80. The primary outcomes were 30-day and 365-day mortality. Results were analyzed with multivariate logistic regression adjusting for demographics and the Elixhauser-van Walraven Comorbidity Index. RESULTS: The adjusted 30-day mortality odds ratios (ORs) were 1.39 (95% confidence interval [CI]: 1.21-1.60), 2.00 (95% CI: 1.75-2.28), and 3.33 (95% CI: 2.90-3.82) for age-groups 40 to 59, 60 to 79, and ≥80, respectively, using the age-group 18 to 39 as the reference. The adjusted 365-day mortality ORs were 1.46 (95% CI: 1.32-1.61), 2.10 (95% CI: 1.91-2.31), and 2.96 (95% CI: 2.67-3.27). CONCLUSION: In critically ill patients, increasing age is associated with higher odds of short-term and long-term death after correcting for existing comorbidities.

Can Sarcopenia Quantified by Ultrasound of the Rectus Femoris Muscle Predict Adverse Outcome of Surgical Intensive Care Unit Patients as well as Frailty? A Prospective, Observational Cohort Study.

OBJECTIVE: To compare sarcopenia and frailty for outcome prediction in surgical intensive care unit (SICU) patients. BACKGROUND: Frailty has been associated with adverse outcomes and describes a status of muscle weakness and decreased physiological reserve leading to increased vulnerability to stressors. However, frailty assessment depends on patient cooperation. Sarcopenia can be quantified by ultrasound and the predictive value of sarcopenia at SICU admission for adverse outcome has not been defined. METHODS: We conducted a prospective, observational study of SICU patients. Sarcopenia was diagnosed by ultrasound measurement of rectus femoris cross-sectional area. Frailty was diagnosed by the Frailty Index Questionnaire based on 50 variables. Relationship between variables and outcomes was assessed by multivariable regression analysis NCT02270502. RESULTS: Sarcopenia and frailty were quantified in 102 patients and observed in 43.1% and 38.2%, respectively. Sarcopenia predicted adverse discharge disposition (discharge to nursing facility or in-hospital mortality, odds ratio 7.49; 95% confidence interval 1.47-38.24; P = 0.015) independent of important clinical covariates, as did frailty (odds ratio 8.01; 95% confidence interval 1.82-35.27; P = 0.006); predictive ability did not differ between sarcopenia and frailty prediction model, reflected by χ values of 21.74 versus 23.44, respectively, and a net reclassification improvement (NRI) of -0.02 (P = 0.87). Sarcopenia and frailty predicted hospital length of stay and the frailty model had a moderately better predictive accuracy for this outcome. CONCLUSIONS: Bedside diagnosis of sarcopenia by ultrasound predicts adverse discharge disposition in SICU patients equally well as frailty. Sarcopenia assessed by ultrasound may be utilized as rapid beside modality for risk stratification of critically ill patients.

Noise Levels in Surgical ICUs Are Consistently Above Recommended Standards.

OBJECTIVE: The equipment, monitor alarms, and acuity of patients in ICUs make it one of the loudest patient care areas in a hospital. Increased sound levels may contribute to worsened outcomes in these particularly vulnerable patients. Our objective was to determine whether ambient sound levels in surgical ICUs comply with recommendations established by the World Health Organization and Environmental Protection Agency, and whether implementation of an overnight "quiet time" intervention is associated with lower ambient sound levels. DESIGN: Prospective, observational cohort study. SETTING: Two comparable 18-bed, surgical ICUs in a large, teaching hospital. Only one ICU had a formal overnight quiet time policy at the start of the study period. MEASUREMENTS AND MAIN RESULTS: Sound levels were measured in 30-second blocks at preselected locations during the day and night over a period of 6 weeks using a simple, hand-held sound meter. All sound measurements in both units at all times exceeded recommended standards. Median minimum sound levels were lower at night in both units (50.8 and 50.3 vs 53.1 and 51.0 dB, p = 0.0003 and p = 0.009) and were similar between the two units (p = 0.52). The maximum overnight sound levels were statistically lower in the unit with the quiet time intervention implemented (62.5 vs 59.6 dB; p = 0.0040) and decreased overnight immediately after implementation of quiet time in the other unit (62.5 vs 56.1 dB; p < 0.0001). Maximum sound levels were lower inside patient rooms (52.2 vs 55.3 dB; p = 0.004), but minimum sound levels were similar (49.1 vs 49.2 dB; p = 0.23). Linear regression analysis showed that ICU census did not significantly influence sound levels. CONCLUSIONS: Ambient sound levels in the surgical ICUs were consistently above levels recommended by the World Health Organization and Environmental Protection Agency at all times. The use of a formal quiet time intervention was associated with a significant, but clinically irrelevant reduction in the median maximum sound level at night. Our results suggest that excessive ambient noise in the ICU is largely attributable to environmental factors, and behavior modifications are unlikely to have a meaningful impact. Future investigations, as well as hospital designs, should target interventions toward ubiquitous noise sources such as ventilation systems, which may not traditionally be associated with patient care.

Fatal pulmonary embolization after negative serial ultrasounds.

BACKGROUND: Isolated distal deep vein thrombosis (DVT) is not traditionally viewed as a potentially life-threatening condition. There are conflicting recommendations regarding its evaluation and treatment, and wide variability in clinical practice. The presentation of this case highlights the fatal potential of this condition. CASE REPORT: This is the report of a previously healthy young woman who presented to the emergency department with calf pain concerning for a DVT. She received two radiologist-performed duplex ultrasound examinations of the affected extremity, both of which were negative, but suffered a sudden cardiac arrest several hours after the second study. Autopsy attributed the death to DVT and pulmonary embolism. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case highlights the risk for fatal pulmonary embolization, even after normal serial ultrasound examinations to exclude DVT.

Disparities Exist in the Application of Low Tidal-volume Ventilation in the Emergency Department.

INTRODUCTION: Low tidal-volume ventilation (LTVV), defined as a maximum tidal volume of 8 milliliters per kilogram (mL/kg) of ideal body weight, is a key component of lung protective ventilation. Although emergency department (ED) initiation of LTVV has been associated with improved outcomes, disparities in LTVV application exist. In this study our aim was to evaluate whether rates of LTVV are associated with demographic and physical characteristics in the ED. METHODS: We conducted a retrospective observational cohort study using a dataset of patients who underwent mechanical ventilation at three EDs in two health systems from January 2016-June 2019. Demographic, mechanical ventilation, and outcome data including mortality and hospital-free days were abstracted by automatic query. A LTVV approach was defined as a tidal volume ≤8 mL/kg ideal body weight. We performed descriptive statistics and univariate analysis as indicated, and created a multivariate logistic regression model. RESULTS: Of 1,029 patients included in the study, 79.5% received LTVV. Tidal volumes of 400-500 mL were used in 81.9% of patients. Approximately 18% of patients had tidal volumes changed in the ED. Female gender (adjusted odds ratio [aOR] 4.17, P< 0.001), obesity (aOR 2.27, P< 0.001), and first-quartile height (aOR 12.2, P < 0.001) were associated with receiving non-LTVV in multivariate regression analysis. Hispanic ethnicity and female gender were associated with first quartile height (68.5%, 43.7%, P < 0.001 for all). Hispanic ethnicity was associated with receiving non-LTVV in univariate analysis (40.8% vs 23.0%, P < 0.001). This relationship did not persist in sensitivity analysis controlling for height, weight, gender, and body mass index. Patients who received LTVV in the ED had 2.1 more hospital-free days compared to those who did not (P = 0.040). No difference in mortality was observed. CONCLUSION: Emergency physicians use a narrow range of initial tidal volumes that may not meet lung-protective ventilation goals, with few corrections. Female gender, obesity, and first-quartile height are independently associated with receiving non-LTVV in the ED. Using LTVV in the ED was associated with 2.1 fewer hospital-free days. If confirmed in future studies, these findings have important implications for achieving quality improvement and health equality.

Impact of interhospital transfer on patients with Alzheimer's disease and other related dementias.

Older adults are often transferred from one emergency department (ED) to another hospital for speciality care, but little is known about whether those transfers positively impact patients, particularly those with Alzheimer's disease and other related dementias (ADRD). In this study we aimed to describe the impact of interhospital transfer on older adults with and without ADRD. In a retrospective review of electronic medical records, we collected data on demographics, insurance type, initial code status, intensive care, length of stay, specialist consult, procedure within 48 hours, and discharge disposition for older adults (≥65years). We included older adults with at least one ED visit, who were transferred to a tertiary care hospital. With logistic regression, we estimated odds of death, intensive care stay, or procedure within 48 hours by ADRD diagnosis. Patients with ADRD more often received a geriatrics (p < 0.001) or palliative care consult (p = 0.038). They were less likely to be full code at admission (p < 0.001) or to be discharged home (p < 0.001). Patients living with ADRD less often received intensive care or a procedure within 48 hours of transfer (odds ratio [OR] 1.87, 95% confidence interval [CI] 1.22-2.88). Patients with ADRD were less likely to receive intensive care unit admission or specialist procedures after transfer. Further study is indicated to comprehensively understand patient-centered outcomes.