Femoral Arterial Doppler Use During Active Cardiopulmonary Resuscitation.

STUDY OBJECTIVE: This study explored femoral arterial Doppler during active cardiopulmonary resuscitation (CPR) to identify and characterize the resumptions of cardiac activity without stopping CPR. METHODS: This was a proof-of-concept study exploring arterial Doppler during cardiac arrest. Patients in cardiac arrest undergoing active CPR were prospectively enrolled. Arterial Doppler of the common femoral artery was recorded during CPR and during pauses in CPR. CPR-induced arterial tracings and native cardiac-induced tracings were analyzed for rate and peak systolic velocity. Cardiac activity on echocardiogram during pause in CPR was classified as "absent," "disorganized," or "organized." Descriptive data and survival are presented as mean and 95% confidence intervals (CI), as well as sensitivity and specificity of Doppler during active CPR in detecting native cardiac pulsations. RESULTS: Sixteen patients with 48 paired Doppler recordings during active CPR, pause in CPR, and associated echocardiogram were enrolled. Native cardiac-induced tracings were visible during 39.6% of pauses in CPR (19 of 48) and during 18.8% of the periods of active CPR (9 of 48). Arterial pulsations were more frequently visualized with organized contractions by echocardiogram (10 of 14, 71%) than disorganized contractions (9 of 22, 41%). Arterial Doppler was 100% specific and 50% sensitive in detecting organized cardiac activity during active CPR. Patients with visible native cardiac pulsations during active CPR demonstrated 0% mortality compared with 67% mortality without visible arterial pulsations. CONCLUSION: Arterial Doppler tracings may identify the resumption of native cardiac activity during active CPR; however, more research is needed.

EFSUMB Clinical Practice Guidelines for Point-of-Care Ultrasound: Part One (Common Heart and Pulmonary Applications) SHORT VERSION.

OBJECTIVE: To evaluate the evidence and produce a summary and recommendations for the most common heart and lung point-of-care ultrasound (PoCUS). METHODS: We reviewed 10 clinical domains/questions related to common heart and lung applications of PoCUS. Following review of the evidence, a summary and recommendations were produced, including assigning levels of evidence (LoE) and grading of recommendation, assessment, development, and evaluation (GRADE). 38 international experts, the expert review group (ERG), were invited to review the evidence presented for each question. A level of agreement of over 75 % was required to progress to the next section. The ERG then reviewed and indicated their level of agreement of the summary and recommendation for each question (using a 5-point Likert scale), which was approved in the case of a level of agreement of greater than 75 %. A level of agreement was defined as a summary of "strongly agree" and "agree" on the Likert scale responses. FINDINGS AND RECOMMENDATIONS: One question achieved a strong consensus for an assigned LoE of 3 and a weak GRADE recommendation (question 1), the remaining 9 questions achieved broad agreement with an assigned LoE of 4 and a weak GRADE recommendation (question 2), three achieved an LoE of 3 with a weak GRADE recommendation (questions 3-5), three achieved an LoE of 3 with a strong GRADE recommendation (questions 6-8) and the remaining two were assigned an LoE of 2 with a strong GRADE recommendation (questions 9 and 10). CONCLUSION: These consensus-derived recommendations should aid clinical practice and highlight areas of further research for PoCUS in acute settings.

EFSUMB Clinical Practice Guidelines for Point-of-Care Ultrasound: Part One (Common Heart and Pulmonary Applications) LONG VERSION.

AIMS: To evaluate the evidence and produce a summary and recommendations for the most common heart and lung applications of point-of-care ultrasound (PoCUS). METHODS: We reviewed 10 clinical domains/questions related to common heart and lung applications of PoCUS. Following review of the evidence, a summary and recommendation were produced, including assignment of levels of evidence (LoE) and grading of the recommendation, assessment, development, and evaluation (GRADE). 38 international experts, the expert review group (ERG), were invited to review the evidence presented for each question. A level of agreement of over 75 % was required to progress to the next section. The ERG then reviewed and indicated their level of agreement regarding the summary and recommendation for each question (using a 5-point Likert scale), which was approved if a level of agreement of greater than 75 % was reached. A level of agreement was defined as a summary of "strongly agree" and "agree" on the Likert scale responses. FINDINGS AND RECOMMENDATIONS: One question achieved a strong consensus for an assigned LoE of 3 and a weak GRADE recommendation (question 1). The remaining 9 questions achieved broad agreement with one assigned an LoE of 4 and weak GRADE recommendation (question 2), three achieving an LoE of 3 with a weak GRADE recommendation (questions 3-5), three achieved an LoE of 3 with a strong GRADE recommendation (questions 6-8), and the remaining two were assigned an LoE of 2 with a strong GRADE recommendation (questions 9 and 10). CONCLUSION: These consensus-derived recommendations should aid clinical practice and highlight areas of further research for PoCUS in acute settings.

A Multicenter, Prospective Study Comparing Subxiphoid and Parasternal Views During Brief Echocardiography: Effect on Image Quality, Acquisition Time, and Visualized Anatomy.

BACKGROUND: Recent literature has suggested echocardiography (echo) may prolong pauses in chest compressions during cardiac arrest. OBJECTVES: We sought to determine the impact of the sonographic approach (subxiphoid [SX] vs. parasternal long [PSL]) on time to image completion, image quality, and visualization of cardiac anatomy during echo, as performed during Advanced Cardiac Life Support. METHODS: This was a multicenter, randomized controlled trial conducted at 29 emergency departments (EDs) assessing the time to image acquisition and image quality between SX and PSL views for echo. Patients were enrolled in the ED and imaged in a simulated cardiac arrest scenario. Clinicians experienced in echo performed both SX and PSL views, first view in random order. Image quality and time to image acquisition were recorded. Echos were evaluated for identification of cardiac landmarks. Data are presented as percentages or medians with interquartile ranges (IQRs). RESULTS: We obtained 6247 echo images, comprising 3124 SX views and 3123 PSL. Overall time to image acquisition was 9.0 s (IQR 6.7-14.1 s). Image acquisition was shorter using PSL (8.8 s, IQR 6.5-13.5 s) compared with SX (9.3 s, IQR 6.7-15.0 s). The image quality was better with the PSL view (3.86 vs. 3.54; p < 0.0001), twice as many SX images scoring in the worst quality category compared with PSL (8.6% vs. 3.7%). Imaging of the pericardium, cardiac chambers, and other anatomic landmarks was superior with PSL imaging. CONCLUSIONS: Echo was performed in < 10 s in > 50% of patients using either imaging technique. Imaging using PSL demonstrated improved image quality and improved identification of cardiac landmarks.

Abscess Incision and Drainage With or Without Ultrasonography: A Randomized Controlled Trial.

STUDY OBJECTIVE: We hypothesize that clinical failure rates will be lower in patients treated with point-of-care ultrasonography and incision and drainage compared with those who undergo incision and drainage after physical examination alone. METHODS: We performed a prospective randomized clinical trial of patients presenting with a soft tissue abscess at a large, academic emergency department. Patients presenting with an uncomplicated soft tissue abscess requiring incision and drainage were eligible for enrollment and randomized to treatment with or without point-of-care ultrasonography. The diagnosis of an abscess was by physical examination, bedside ultrasonography, or both. Patients randomized to the point-of-care ultrasonography group had an incision and drainage performed with bedside ultrasonographic imaging of the abscess. Patients randomized to the non-point-of-care ultrasonography group had an incision and drainage performed with physical examination alone. Comparison between groups was by comparing means with 95% confidence intervals. The primary outcome was failure of therapy at 10 days, defined as a repeated incision and drainage, following a per-protocol analysis. Multivariate analysis was performed to control for study variables. Our study was designed to detect a clinically important difference between groups, which we defined as a 13% difference. RESULTS: A total of 125 patients were enrolled, 63 randomized to the point-of-care ultrasonography group and 62 to physical examination alone. After loss to follow-up and misallocation, 54 patients in the ultrasonography group and 53 in the physical examination alone group were analyzed. The overall failure rate for all patients enrolled in the study was 10.3%. Patients who were evaluated with ultrasonography were less likely to fail therapy and have repeated incision and drainage, with a difference between groups of 13.3% (95% confidence interval 0.0% to 19.4%). Abscess locations were predominantly torso (21%), buttocks (21%), lower extremity (18%), and axilla or groin (16%). There was no difference in baseline characteristics between groups relative to abscess size, duration of symptoms before presentation, percentage with cellulitis, and treatment with antibiotics. CONCLUSION: Patients with soft tissue abscesses who were undergoing incision and drainage with point-of-care ultrasonography demonstrated less clinical failure compared with those treated without point-of-care ultrasonography.

Ultrasound-Guided Drainage for Pediatric Soft Tissue Abscesses Decreases Clinical Failure Rates Compared to Drainage Without Ultrasound: A Retrospective Study.

OBJECTIVES: Soft tissue abscesses are common in the pediatric emergency department (ED). Ultrasound (US) can be used to both diagnose soft tissue abscesses as well as guide drainage. We hypothesized that clinical failure rates would be less in pediatric patients with suspected skin abscesses when evaluated with US. METHODS: We performed a retrospective review of suspected pediatric skin abscesses at 4 EDs over a 22-month period. Cases were identified through electronic medical record descriptions, discharge diagnoses, and US database records. Data on US use, findings, and outcomes were abstracted to an electronic database. Comparisons between groups included US versus non-US (primary outcome) as well as surgical drainage vs nonsurgical drainage (secondary outcome). RESULTS: A total of 377 patients were seen with concern for a potential skin abscess; 141 patients (37.4%) underwent US imaging during their visit, and 239 (63.4%) underwent incision and drainage (I&D) during their ED stay: 90 with US and 149 without. The failure rate for patients evaluated with US was significantly lower than that for those evaluated without US (4.4% versus 15.6%; P < .005). Thirty-four (11.3%) of the 302 patients with a diagnosis of an abscess failed therapy: 19 (8.2%) after I&D and 15 (21.1%) after nonsurgical management. Failure after I&D was associated with a smaller abscess cavity on US imaging (17.2 versus 44.8 mm3 ; P < .05). CONCLUSIONS: The use of US for patients with a suspected skin abscess was associated with a reduction in the amount of clinical failure rates after both surgical drainage and nonsurgical therapy. Ultrasound should be used when evaluating or treating patients with abscesses.

Pulmonary effects of intravenous atropine induce ventilation perfusion mismatch.

Atropine is used for a number of medical conditions, predominantly for its cardiovascular effects. Cholinergic nerves that innervate pulmonary smooth muscle, glands, and vasculature may be affected by anticholinergic medications. We hypothesized that atropine causes alterations in pulmonary gas exchange. We conducted a prospective interventional study with detailed physiologic recordings in anesthetized, spontaneously breathing rats (n = 8). Animals breathing a normoxic gas mixture titrated to a partial arterial pressure of oxygen of 110-120 were exposed to an escalating dose of intravenous atropine (0.001, 0.01, 0.1, 5.0, and 20.0 mg/kg body mass). Arterial blood gas measurements were recorded every 2 min (×5) at baseline, and following each of the 5 doses of atropine. In addition, the animals regional pulmonary blood flow was measured using neutron-activated microspheres. Oxygenation decreased immediately following intravenous administration of atropine, despite a small increase in the volume of inspired air with no change in respiratory rate. Arterial blood gas analysis showed an increase in pulmonary dysfunction, characterized by a widening of the alveolar-arteriole gradient (p < 0.003 all groups except for the lowest dose of atropine). The microsphere data demonstrates an abrupt and marked heterogeneity of pulmonary blood flow following atropine treatment. In conclusion, atropine was found to decrease pulmonary gas exchange in a dose-dependent fashion in this rat model.

Sonoelastographic characteristics of abscess induration associated with therapy failure.

OBJECTIVES: Sonoelastography can visualize components of skin and soft tissue abscesses, including the abscess cavity and surrounding induration, related to the patient's response to the infection. We speculate that characteristics of the induration surrounding an abscess may predict which abscesses will eventually fail therapy. METHODS: We conducted a prospective trial of patients with a suspected skin abscess requiring surgical drainage who were enrolled from the emergency department of an urban tertiary care center. In this pilot study, all patients underwent incision and drainage for the suspected abscesses. Abscesses (n = 56) were imaged in orthogonal planes (long-axis and transverse to the body part) using B-mode sonography and elastography before incision and drainage. Telephone follow-up using a standardized questionnaire was performed 7 to 10 days after the initial drainage procedure to determine therapy failure. Physicians blinded to patient outcome analyzed the sonograms for predetermined image characteristics of the abscess induration. RESULTS: All patients underwent incision and drainage, but 16.1% of patients failed therapy. Asymmetry of the surrounding induration was associated with therapy failure. A higher percentage of patients who failed therapy had asymmetry (66%; 95% confidence interval, 35.1%-88.3%) versus those who were successfully treated (12.8%; 95% confidence interval, 5.6%-25.6%; P = .003). In all patients, the mean volumes ± SD of the abscess cavity and induration were 2.2 ± 3.7 and 19.9 ± 24.7 cm, respectively, with a mean volume ratio (induration to abscess cavity) of 31.9 to 1. CONCLUSIONS: We describe sonographic characteristics of the abscess induration imaged with sonoelastography that are associated with therapy failure. We found that patients with asymmetric induration visualized with sonoelastography have higher rates of therapy failure.

Clinical failure in abscess treatment: the role of ultrasound and incision and drainage.

PURPOSE: Skin and soft tissue abscesses are commonly treated in emergency departments (ED). The use of bedside ultrasound may improve patient outcomes. The primary objective of this study was to examine the relationship between ultrasound use and risk of treatment failure in ED patients treated for abscesses. METHODS: In this multi-center observational study, we reviewed medical records of adult patients evaluated for abscesses. Demographics, infection characteristics, treatments rendered, use of ultrasound (for diagnosis and/or treatment) and follow-up data were collected from electronic medical record review. Treatment failure, the primary outcome, was defined as any surgical intervention after the initial ED visit. Multivariable logistic regression tested whether incision and drainage utilizing ultrasound was associated with reduced treatment failure. RESULTS: We identified 609 patients diagnosed with abscesses over a 22-month period. Of them 75% were treated with incision and drainage, 55% had an ultrasound and 15% failed treatment. Multi-variable analysis demonstrated an 8% probability of failure with ultrasound plus incision and drainage, 14% with blind incision and drainage and 25% without incision and drainage. Individuals with incision and drainage performed were 50% less likely to fail treatment (RR 0.53, 95%CI 0.35-0.81) and 70% less likely to fail treatment (RR 0.30, 95%CI 0.18-0.51) with ultrasound and incision and drainage. CONCLUSIONS: The use of ultrasound in diagnosing and or/treating patients with abscesses in the ED is associated with decreased treatment failure risk when utilized with incision and drainage. Consideration of ultrasound use in other studies which assess treatment methods in relation to patient outcomes may be warranted.

RéSUMé : OBJECTIF: Les abcès de la peau et des tissus mous sont couramment traités dans les services d'urgence (SU). L'utilisation de l'échographie au chevet du patient peut améliorer les résultats des patients. L'objectif principal de cette étude était d'examiner la relation entre l'utilisation de l'échographie et le risque d'échec du traitement chez les patients des urgences traités pour des abcès. MéTHODES: Dans cette étude d'observation multicentrique, nous avons examiné les dossiers médicaux des patients adultes évalués pour les abcès. Les données démographiques, les caractéristiques de l'infection, les traitements rendus, l'utilisation de l'échographie (pour le diagnostic et/ou le traitement) et les données de suivi ont été recueillies à partir de l'examen des dossiers médicaux électroniques. L'échec du traitement, le critère de jugement principal, a été défini comme toute intervention chirurgicale après la visite initiale au service d'urgence. Une régression logistique multivariable a permis de vérifier si l'incision et le drainage par ultrasons étaient associés à une réduction de l'échec du traitement. RéSULTATS: Nous avons identifié 609 patients diagnostiqués avec des abcès sur une période de 22 mois. Parmi eux, 75 % ont été traités par incision et drainage, 55% ont eu une échographie et 15 % ont échoué le traitement. L'analyse multivariée a démontré une probabilité d'échec de 8 % avec échographie plus incision et drainage, 14 % avec incision et drainage aveugle et 25 % sans incision et drainage. Les personnes chez qui l'on a pratiqué une incision et un drainage avaient 50 % moins de risques d'échouer le traitement (RR 0,53, 95 % IC 0,35-0,81) et 70 % moins de risques d'échouer le traitement (RR 0,30, 95 % IC 0,18-0,51) avec l'échographie et l'incision et le drainage. CONCLUSIONS: L'utilisation de l'échographie pour le diagnostic et/ou le traitement des patients atteints d'abcès aux urgences est associée à une diminution du risque d'échec du traitement lorsqu'elle est utilisée avec l'incision et le drainage. Il peut être justifié d'envisager l'utilisation de l'échographie dans d'autres études qui évaluent les méthodes de traitement en fonction des résultats pour les patients.

Dengue Management in Triage using Ultrasound in children from Cambodia: a prospective cohort study.

BACKGROUND: Dengue is a mosquito-borne viral infection with increasing global prevalence. It is endemic in more than 100 countries, with a heavy burden in Asia. Ultrasound findings including gallbladder wall thickening, ascites, and pleural effusions secondary to plasma leakage have been described in dengue. We aimed to determine if the presence of point-of-care ultrasound findings early in suspected dengue could predict clinical worsening in ambulatory pediatric patients. METHODS: We did a prospective, single-blinded, observational cohort study at a children's hospital in Siem Reap, Cambodia during periods of dengue outbreak. Ambulatory patients were screened and children ages > 3 month and ≤ 16 years with suspected acute, non-severe dengue were enrolled. Subjects had chest and abdominal ultrasound exams. Independently, subjects were evaluated by a blinded physician who determined a treatment plan as per usual practice. Follow-up was conducted 7-10 days after the initial visit. Analysis of ultrasound findings was performed to determine their relationship with outcome measures including need for unplanned hospital visits or admissions. FINDINGS: A total of 2,186 children were screened during periods of national dengue outbreak in Cambodia in consecutive years 2018-2019, and 253 children met eligibility criteria. Results showed patients with gallbladder wall thickening (> 3·0 mm) who were discharged had a significantly more likely need for unplanned visit or hospitalization than those with normal gallbladder wall, 67% (95% CI 44 - 84) versus 17% (95% CI 12 - 24), p < 0.0001. Subjects with any abnormal ultrasound finding were more likely to be directly admitted versus discharged upon initial presentation, 62·2% (95% CI 46.1 - 76.0) versus 19.5% (95% CI 14.8 - 25.4), p < 0.0001. INTERPRETATION: Point-of-care ultrasound findings, particularly gallbladder wall thickening, in suspected early dengue can help predict disease progression in ambulatory patients. Ultrasound has potential to help guide management of suspected dengue patients and resource management during periods of dengue outbreak. FUNDING: Society for Academic Emergency Medicine Foundation.

A randomized controlled trial of incision and drainage versus ultrasonographically guided needle aspiration for skin abscesses and the effect of methicillin-resistant Staphylococcus aureus.

STUDY OBJECTIVE: The incidence of skin and soft tissue infections has increased dramatically during the last decade, in part because of increased prevalence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). Incision and drainage is considered the primary intervention; however, some clinicians prefer ultrasonographically guided needle aspiration because it represents a less invasive alternative. Our hypothesis is that ultrasonographically guided needle aspiration is equivalent to incision and drainage in treating simple skin and soft tissue abscesses. METHODS: This study was a nonblinded randomized controlled trial. Patients with uncomplicated superficial abscesses were randomized to incision and drainage with packing or ultrasonographically guided needle aspiration. Purulence obtained from the abscess was cultured to identify the causative organism. Bedside ultrasonography was performed pre- and postintervention to confirm the presence or absence of an abscess cavity. Patients were followed up at 48 hours (in person by a clinician) and on day 7 (telephone follow-up by research staff). The primary outcome was a combination of sonographic resolution and clinical resolution of the signs and symptoms of ongoing infection at day 7. The signs and symptoms of ongoing infection include increasing pain, erythema, and the presence of pus. Resolution was assessed with both sonographic resolution (day 0 and day 2) and improvement of clinical symptoms (day 2) and resolution of clinical symptoms (day 7) without further intervention. RESULTS: A total of 101 patients were enrolled, 54 incision and drainage and 47 ultrasonographically guided needle aspiration patients. At initial presentation, 60% (95% confidence interval [CI] 45% to 70%) of needle aspirations yielded little or no purulence, despite sonographic visualization of an abscess cavity and sonographic guidance during the procedure. The overall success of ultrasonographically guided needle aspiration was 26% (95% CI 18% to 44%) compared with 80% (95% CI 66% to 89%) success in patients randomized to incision and drainage. The difference between groups was 54% (95% CI 35% to 69%). Overall success of both incision and drainage and ultrasonographically guided needle aspiration was lower in patients with CA-MRSA. Patients with CA-MRSA (n=33) were less likely to receive successful drainage with needle aspiration (8% versus 55%) or incision and drainage (61% versus 89%). The difference for needle aspiration and incision and drainage was 47% (95% CI 15% to 57%) and 28% (95% CI 4% to 45%), respectively. CONCLUSION: Ultrasonographically guided needle aspiration is insufficient therapy for skin abscesses. The presence of CA-MRSA decreases the success of both incision and drainage and ultrasonographically guided needle aspiration.

Development and validation of a novel image quality rating scale for echocardiography during cardiac arrest.

OBJECTIVE: Research into echocardiography (echo) during cardiac arrest has suffered from methodological flaws that limit aggregation of findings. We developed and validated a novel image rating scale for qualitative analysis of echo images obtained during resuscitation. METHODS: A novel 5-point ordinal rating scale was developed and validated using recorded echo images from 145 consecutive cardiac arrest patients. Recorded echo images were reviewed in a blinded fashion by investigators experienced in cardiac arrest echo, and image quality was rated using this scale. Cardiac activity was subsequently classified as no activity, disorganized activity and organized activity. The primary outcome was inter-rater agreement using the image quality rating scale. Secondary outcome was the qualitative evaluation of the type of cardiac activity. RESULTS: A total of 235 ultrasounds were analyzed by study investigators using the image quality rating scale. The overall image quality agreement between reviewers using the scale was good with a weighted kappa of 0.65. Agreement for image quality in subxyphoid images was greater than in parasternal images (0.65-0.52). Echo analysis of cardiac activity showed no activity (33%), disorganized activity (18%), and organized activity (49%). Agreement was great for presence or absence of "cardiac activity" and "organized cardiac activity" with a kappa of 0.84 and 0.78. CONCLUSIONS: A novel image quality rating scale for echo during cardiac arrest demonstrates substantial agreement between reviewers. Agreement regarding the presence or absence, as well as the organization of cardiac activity was substantial.

Echocardiographic pre-pause imaging and identifying the acoustic window during CPR reduces CPR pause time during ACLS - A prospective Cohort Study.

OBJECTIVES: Pre-pause imaging during cardiopulmonary resuscitation (CPR) involves the acquisition of poor-quality, brief images immediately prior to stopping CPR to allow shorter, better-quality images during the pause. We hypothesize that pre-pause imaging is associated with a decrease in CPR pause length and shorter image acquisition time. METHODS: Prospective, interventional cohort study enrolling out-of-hospital (OOH) cardiac arrest patients. Pre-pause imaging involves pre-localizing of the approximate sonographic window during CPR to support subsequent fine tuning when CPR pauses. Physicians were educated on pre-pause imaging and data was recorded prior- and post- introduction of pre-pause imaging into American cardiac life support (ACLS). Timing of CPR pauses and identification of interventions and events during pause were recorded (e.g., intubation, defibrillation, multiple cardiac ultrasounds). Ultrasound (US) images were reviewed for image quality using a 5-point scale. Primary outcome was length of CPR pause with and without pre-pause imaging. Secondary outcome included US length. RESULTS: One hundred and forty five subjects presenting after OOH cardiac arrest were enrolled over 13 months, 70 during the baseline period prior to pre-pause imaging and 75 after pre-pause imaging was integrated into ACLS. Pre-pause imaging decreased CPR pause length from 28.3 s (95%CI 25.1-31.5) to 12.8 s (95%CI 11.9-13.7). US image acquisition time decreased with pre-pause imaging from 20.4 (95%CI 18.0-22.7) to 11.0 s (95%CI 10.1-11.8). US image quality was unchanged despite the decrease in image acquisition time. (3.0 (95%CI 2.8-3.2) vs 2.7 (95%CI 2.5-2.9)). Multivariate modeling showed that ultrasound did not prolong CPR pause length. CONCLUSION: Pre-pause imaging was associated with significant decrease in CPR pause length and US image acquisition time. Pre-pause imaging should be encouraged for any clinicians who use ultrasound during ACLS.

Comparison of outcomes between pulseless electrical activity by electrocardiography and pulseless myocardial activity by echocardiography in out-of-hospital cardiac arrest; secondary analysis from a large, prospective study.

OBJECTIVE: To measure prevalence of discordance between electrical activity recorded by electrocardiography (ECG) and myocardial activity visualized by echocardiography (echo) in patients presenting after cardiac arrest and to compare survival outcomes in cohorts defined by ECG and echo. METHODS: This is a secondary analysis of a previously published prospective study at twenty hospitals. Patients presenting after out-of-hospital arrest were included. The cardiac electrical activity was defined by ECG and contemporaneous myocardial activity was defined by bedside echo. Myocardial activity by echo was classified as myocardial asystole--the absence of myocardial movement, pulseless myocardial activity (PMA)--visible myocardial movement but no pulse, and myocardial fibrillation--visualized fibrillation. Primary outcome was the prevalence of discordance between electrical activity and myocardial activity. RESULTS: 793 patients and 1943 pauses in CPR were included. 28.6% of CPR pauses demonstrated a difference in electrical activity (ECG) and myocardial activity (echo), 5.0% with asystole (ECG) and PMA (echo), and 22.1% with PEA (ECG) and myocardial asystole (echo). Twenty-five percent of the 32 pauses in CPR with a shockable rhythm by echo demonstrated a non-shockable rhythm by ECG and were not defibrillated. Survival for patients with PMA (echo) was 29.1% (95%CI-23.9-34.9) compared to those with PEA (ECG) (21.4%, 95%CI-17.7-25.6). CONCLUSION: Patients in cardiac arrest commonly demonstrate different electrical (ECG) and myocardial activity (echo). Further research is needed to better define cardiac activity during cardiac arrest and to explore outcome between groups defined by electrical and myocardial activity.

Quantitative characterization of left ventricular function during pulseless electrical activity using echocardiography during out-of-hospital cardiac arrest.

BACKGROUND: Several prospective studies have demonstrated that the echocardiographic detection of any myocardial activity during PEA is strongly associated with higher rates of return of spontaneous circulation (ROSC). We hypothesized that PEA represents a spectrum of disease in which not only the presence of myocardial activity, but more specifically that the degree of left ventricular (LV) function would be a predictor of outcomes. The purpose of this study was to retrospectively assess the association between LV function and outcomes in patients with OHCA. MATERIALS AND METHODS: Using prospectively obtained data from an observational cohort of patients receiving focused echocardiography during cardiopulmonary resuscitation (CPR) in the Emergency Department (ED) setting, we analyzed 312 consecutive subjects with available echocardiography images with initial rhythm of PEA. We used left ventricular systolic fractional shortening (LVFS), a unidimensional echocardiographic parameter to perform the quantification of LV function during PEA. Regression analyses were performed independently to evaluate for relationships between LVFS and a primary outcome of ROSC and secondary outcome of survival to hospital admission. We analyzed LVFS both as a continuous variable and as a categorial variable using the quartiles and the median to perform multiple different comparisons and to illustrate the relationship of LVFS and outcomes of interest. We performed survival analysis using Cox proportional hazards model to evaluate the hazard corresponding to length of resuscitation. RESULTS: We found a positive association between LVFS and the primary outcome of ROSC (OR 1.04, 95%CI 1.01-1.08), but not with the secondary outcome of survival to hospital admission (OR 1.02, 95%CI 0.96-1.08). Given that the relationship was not linear and that we observed a threshold effect in the relationship between LVFS and outcomes, we performed an analysis using quartiles of LVFS. The predicted probability of ROSC was 75% for LVFS between 23.4-96% (fourth quartile) compared to 47% for LVFS between 0-4.7% (first quartile). The hazard of not achieving ROSC was significantly greater for subjects with LVFS below the median (13.1%) compared to the subgroup with LVFS greater than 13.1% (p < 0.05), with the separation of the survival curves occurring at approximately 40 min of resuscitation duration. CONCLUSIONS: Left ventricular function measured by LVFS is positively correlated with higher probability of ROSC and may be associated with higher chances of survival in patients with PEA arrest.

Tools for Measuring Clinical Ultrasound Competency: Recommendations From the Ultrasound Competency Work Group.

Competency in clinical ultrasound is essential to ensuring safe patient care. Competency in clinical ultrasound includes identifying when to perform a clinical ultrasound, performing the technical skills required for ultrasound image acquisition, accurately interpreting ultrasound images, and incorporating sonographic findings into clinical practice. In this concept paper, we discuss the advantages and limitations of existing tools to measure ultrasound competency. We propose strategies and future directions for assessing competency in clinical ultrasound.

Identification of congestive heart failure via respiratory variation of inferior vena cava diameter.

INTRODUCTION: Rapid diagnosis of volume overload in patients with suspected congestive heart failure (CHF) is necessary for the timely administration of therapeutic agents. We sought to use the measurement of respiratory variation of inferior vena cava (IVC) diameter as a diagnostic tool for identification of CHF in patients presenting with acute dyspnea. METHODS: The IVC was measured sonographically during a complete respiratory cycle of 46 patients meeting study criteria. Percentage of respiratory variation of IVC diameter was compared to the diagnosis of CHF or alternative diagnosis. RESULTS: Respiratory variation of IVC was smaller in patients with CHF (9.6%) than without CHF (46%) and showed good diagnostic accuracy with area under the receiver operating characteristic curve of 0.96. Receiver operating characteristic curve analysis showed optimum cutoff of 15% variation or less of IVC diameter with 92% sensitivity and 84% specificity for the diagnosis of CHF. CONCLUSION: Inferior vena cava ultrasound is a rapid, reliable means for identification of CHF in the acutely dyspneic patient.