Ten Influential Point-of-Care Ultrasound Papers: 2022 in Review.

Keeping up with the latest developments in the point-of-care ultrasound (POCUS) literature is challenging, as with any area of medicine. Our group of POCUS experts has selected 10 influential papers from the past 12 months and provided a short summary of each. We hope to provide emergency physicians, intensivists, and other acute care providers with a succinct update concerning some key areas of ultrasound interest.

Automated Seizure Detection in Patients with Cardiac Arrest: A Retrospective Review of Ceribell™ Rapid-EEG Recordings.

BACKGROUND: In patients with cardiac arrest who remain comatose after return of spontaneous circulation, seizures and other abnormalities on electroencephalogram (EEG) are common. Thus, guidelines recommend urgent initiation of EEG for the evaluation of seizures in this population. Point-of-care EEG systems, such as Ceribell™ Rapid Response EEG (Rapid-EEG), allow for prompt initiation of EEG monitoring, albeit through a reduced-channel montage. Rapid-EEG incorporates an automated seizure detection software (Clarity™) to measure seizure burden in real time and alert clinicians at the bedside when a high seizure burden, consistent with possible status epilepticus, is identified. External validation of Clarity is still needed. Our goal was to evaluate the real-world performance of Clarity for the detection of seizures and status epilepticus in a sample of patients with cardiac arrest. METHODS: This study was a retrospective review of Rapid-EEG recordings from all the patients who were admitted to the medical intensive care unit at Kent Hospital (Warwick, RI) between 6/1/2021 and 3/18/2022 for management after cardiac arrest and who underwent Rapid-EEG monitoring as part of their routine clinical care (n = 21). Board-certified epileptologists identified events that met criteria for seizures or status epilepticus, as per the 2021 American Clinical Neurophysiology Society's Standardized Critical Care EEG Terminology, and evaluated any seizure burden detections generated by Clarity. RESULTS: In this study, 4 of 21 patients with cardiac arrest (19.0%) who underwent Rapid-EEG monitoring had multiple electrographic seizures, and 2 of those patients (9.5%) had electrographic status epilepticus within the first 24 h of the study. None of these ictal abnormalities were detected by the Clarity seizure detection system. Clarity showed 0% seizure burden throughout the entirety of all four Rapid-EEG recordings, including the EEG pages that showed definite seizures or status epilepticus. CONCLUSIONS: The presence of frequent electrographic seizures and/or status epilepticus can go undetected by Clarity. Timely and careful review of all raw Rapid-EEG recordings by a qualified human EEG reader is necessary to guide clinical care, regardless of Clarity seizure burden measurements.

Ten Influential Point-of-Care Ultrasound Papers: 2021 in Review.

The ongoing rapid expansion of point-of-care ultrasound (POCUS) and its corresponding supporting literature leaves the frontline clinician in a difficult position when trying to keep abreast of the latest developments. Our group of POCUS experts has selected ten influential POCUS-related papers from the past twelve months and provided a short summary of each. Our aim is to give to emergency physicians, intensivists, and other acute care providers key information, helping them to keep up to date on rapidly evolving POCUS literature.

The Utility of Point-of-Care Ultrasound in the Pediatric Intensive Care Unit.

Objectives: Point of care ultrasound (POCUS) in adult critical care environments has become the standard of care in many hospitals. A robust literature shows its benefits for both diagnosis and delivery of care. The utility of POCUS in the pediatric intensive care unit (PICU), however, is understudied. This study describes in a series of PICU patients the clinical indications, protocols, findings and impact of pediatric POCUS on clinical management. Design: Retrospective analysis of 200 consecutive POCUS scans performed by a PICU physician. Patients: Pediatric critical care patients who required POCUS scans over a 15-month period. Setting: The pediatric and cardiac ICUs at a tertiary pediatric care center. Interventions: Performance of a POCUS scan by a pediatric critical care attending with advanced training in ultrasonography. Measurement and Main Results: A total of 200 POCUS scans comprised of one or more protocols (lung and pleura, cardiac, abdominal, or vascular diagnostic protocols) were performed on 155 patients over a 15-month period. The protocols used for each scan reflected the clinical question to be answered. These 200 scans included 133 thoracic protocols, 110 cardiac protocols, 77 abdominal protocols, and 4 vascular protocols. In this series, 42% of scans identified pathology that required a change in therapy, 26% confirmed pathology consistent with the ongoing plans for new therapy, and 32% identified pathology that did not result in initiation of a new therapy. Conclusions: POCUS performed by a trained pediatric intensivist provided useful clinical information to guide patient management.

Assessing Competence in Critical Care Echocardiography: Development and Initial Results of an Examination and Certification Processes.

OBJECTIVES: To describe the development and initial results of an examination and certification process assessing competence in critical care echocardiography. DESIGN: A test writing committee of content experts from eight professional societies invested in critical care echocardiography was convened, with the Executive Director representing the National Board of Echocardiography. Using an examination content outline, the writing committee was assigned topics relevant to their areas of expertise. The examination items underwent extensive review, editing, and discussion in several face-to-face meetings supervised by National Board of Medical Examiners editors and psychometricians. A separate certification committee was tasked with establishing criteria required to achieve National Board of Echocardiography certification in critical care echocardiography through detailed review of required supporting material submitted by candidates seeking to fulfill these criteria. SETTING: The writing committee met twice a year in person at the National Board of Medical Examiner office in Philadelphia, PA. SUBJECTS: Physicians enrolled in the examination of Special Competence in Critical Care Electrocardiography (CCEeXAM). MEASUREMENTS AND MAIN RESULTS: A total of 524 physicians sat for the examination, and 426 (81.3%) achieved a passing score. Of the examinees, 41% were anesthesiology trained, 33.2% had pulmonary/critical care background, and the majority had graduated training within the 10 years (91.6%). Most candidates work full-time at an academic hospital (46.9%). CONCLUSIONS: The CCEeXAM is designed to assess a knowledge base that is shared with echocardiologists in addition to that which is unique to critical care. The National Board of Echocardiography certification establishes that the physician has achieved the ability to independently perform and interpret critical care echocardiography at a standard recognized by critical care professional societies encompassing a wide spectrum of backgrounds. The interest shown and the success achieved on the CCEeXAM by practitioners of critical care echocardiography support the standards set by the National Board of Echocardiography for testamur status and certification in this imaging specialty area.

Reversal of Severe Multiorgan Failure Associated With Sickle Cell Crisis Using Plasma Exchange: A Case Series.

OBJECTIVE: Red blood cell exchange (RBCE) is the standard of care for patients with sickle cell disease (SCD) who present with severe vaso-occlusive crisis (VOC). However, subsets of these critically ill patients have progressive multiorgan failure (MOF) despite RBCE therapy. The purpose of this case series is to describe the use of plasma exchange (PLEX) for the treatment of SCD-related MOF that is refractory to RBCE. METHODS: A retrospective case review of patients with severe MOF from sickle cell crisis unresponsive to RBCE who underwent PLEX in a 14-bed adult medical intensive care unit (ICU) at a tertiary care university hospital over a 4-year time period. Key laboratory data including complete blood count, indices of hemolysis, and markers of organ failure were recorded before and after both RBCE and PLEX. RESULTS: Our primary objective is to evaluate the effectiveness of PLEX, in addition to RBCE, on organ dysfunction, laboratory indices, and mortality. Of the 7 patients, 6 survived. Of the patients who survived, all remained hemodynamically stable during PLEX sessions and showed both clinical and laboratory evidences of improvement in hemolysis and organ function. Average time from completion of first PLEX treatment to initial laboratory signs of organ failure reversal for patients who survived was 15.6 hours, the average length of stay in the ICU was 5.6 days, and the average total length of stay in the hospital was 14 days. CONCLUSIONS: Plasma exchange, in addition to RBCE, may be a novel synergistic treatment option to decrease risk of mortality in patients with refractory VOC and MOF.

Assessment of Diaphragm Function and Pleural Pressures During Thoracentesis.

BACKGROUND: This prospective observational study reports on diaphragm excursion, velocity of diaphragm contraction, and changes in pleural pressure that occur with thoracentesis. METHODS: Twenty-eight patients with pleural effusion underwent therapeutic thoracentesis. Diaphragm excursion and velocity of diaphragm contraction were measured with M-mode ultrasonography of the affected hemidiaphragm. Pleural pressure was measured at each aliquot of 250 mL of fluid removal. Fluid removal was continued until no more fluid could be withdrawn, unless there was evidence of nonexpandable lung defined as a pleural elastance greater > 14.5 cm H2O/L and/or ipsilateral anterior chest discomfort. RESULTS: Twenty-three patients had expandable lung, and five patients had nonexpandable lung. Velocity of diaphragm contraction (mean ± SD) increased from 1.5 ± 0.4 cm/s to 2.8 ± 0.4 cm/s pre-thoracentesis and post-thoracentesis, respectively (CI, 0.93-1.61; P < .001) in subjects with expandable lung. Velocity of diaphragm contraction (mean ± SD) increased from 2.0 ± 0.4 cm/s to 2.3 ± 0.4 cm/s pre-thoracentesis and post-thoracentesis (P = .45) in subjects with nonexpandable lung. Diaphragm excursion was significantly increased in subjects with expandable lung at the end of thoracentesis; diaphragm excursion did not increase to a significant extent in patients with nonexpandable lung. CONCLUSIONS: The velocity of diaphragm contraction and diaphragm excursion increased in association with fluid removal with thoracentesis in patients with expandable lung, whereas it did not significantly change in patients with nonexpandable lung. This may derive from improvement in loading conditions of the diaphragm in patients with expandable lung related to its preload and length-tension characteristics.

Ultrasound Billing for Intensivists.

Point-of-care ultrasonography is a key skill for the critical care clinician and is gaining widespread acceptance by clinicians in all areas of medicine. In addition to mastery of image acquisition, image interpretation, and clinical application, intensivists need to be adept with billing for their scanning activity. This article summarizes the requirements for documentation and image storage that must be met to obtain reimbursement for point-of-care ultrasonography services.

Feasibility, Safety, and Utility of Advanced Critical Care Transesophageal Echocardiography Performed by Pulmonary/Critical Care Fellows in a Medical ICU.

BACKGROUND: Competence in advanced critical care transesophageal echocardiography allows the intensivist to diagnose and manage cardiopulmonary failure when transthoracic echocardiography is not sufficient to answer the clinical question. This report describes the feasibility, safety, and utility of transesophageal echocardiography performed by pulmonary and critical care fellows in a medical ICU in critically ill patients who were mechanically ventilated. METHODS: This longitudinal descriptive study of advanced transesophageal echocardiography was performed in patients who were mechanically ventilated. The complications and clinical utility of the examinations were abstracted from review of the image set, the written report, and the patient chart. Influence on diagnosis was classified as confirming the initial clinical diagnosis or identification of a new or unanticipated finding. Therapeutic impact was categorized as no change in therapy resulting from the study findings or as change in therapy resulting from the study findings. RESULTS: The examination was feasible in all patients in whom it was attempted, and there were no complications of the procedure. New or actionable findings were identified in 43 (28%) studies, and 109 (72%) studies confirmed the initial clinical diagnosis. The findings resulted in a change in clinical management in 58 (38%) patients. CONCLUSIONS: Critical care transesophageal echocardiography is feasible, safe, and has clinical utility. It can be safely and effectively performed by fellows within the context of their critical care training with faculty supervision. Pulmonary critical care fellowship training programs should consider introducing critical care transesophageal echocardiography as a useful clinical tool.

Effectiveness of a Critical Care Ultrasonography Course.

BACKGROUND: Widespread use of critical care ultrasonography (CCUS) for the management of patients in the ICU requires an effective training program. The effectiveness of national and regional CCUS training courses is not known. This study describes a national-level, simulation-based, 3-day CCUS training program and evaluates its effectiveness. METHODS: Five consecutive CCUS courses, with a total of 363 people, were studied. The 3-day CCUS training program consisted of didactic lectures, ultrasonography interpretation sessions, and hands-on modules with live models. Thoracic, vascular, and abdominal ultrasonography were taught in addition to goal-directed echocardiography. Learners rotated between hands-on training and interpretation sessions. The teacher-to-learner ratio was 1:3 during hands-on training. Interpretation sessions were composed of interactive small groups that reviewed normal and abnormal ultrasonography images. Learners completed a video-based examination before and after completion of the courses. Hands-on image acquisition skills were tested at the completion of the course. RESULTS: Average scores on the pretest and posttest were 57% and 90%, respectively (P < .001). The average score on the hands-on test was 86%. Learners aged 20 to 39 years compared with learners ≥ 40 years old scored better on the pretest (64% vs 51%; P < 0.001), posttest (91% vs 88%; P < .010), and hands-on test (90% vs 82%; P < .001). CONCLUSIONS: Learners demonstrated a significant improvement in written test scores that assessed cognitive and image interpretation abilities. In addition, they demonstrated acquisition of practical skills as evidenced by high scores during hands-on testing. Further studies are needed to determine if a simulation-based CCUS course will translate into effective clinical practice and to measure the durability of training. This 3-day course is an effective method to train large groups of critical care clinicians in the skills requisite for CCUS (image acquisition and image interpretation).

A Whole-Body Approach to Point of Care Ultrasound.

Ultrasonography is an essential imaging modality in the ICU used to diagnose and guide the treatment of cardiopulmonary failure. Critical care ultrasonography requires that all image acquisition, image interpretation, and clinical applications of ultrasonography are personally performed by the critical care clinician at the point of care and that the information obtained is combined with the history, physical, and laboratory information. Point-of-care ultrasonography is often compartmentalized such that the clinician will focus on one body system while performing the critical care ultrasonography examination. We suggest a change from this compartmentalized approach to a systematic whole-body ultrasonography approach. The standard whole-body ultrasonography examination includes thoracic, cardiac, limited abdominal, and an evaluation for DVT. Other elements of ultrasonography are used when clinically indicated. Each of these elements is reviewed in this article and are accompanied by a link to pertinent cases from the Ultrasound Corner section of CHEST.

A Serious Adult Intraosseous Catheter Complication and Review of the Literature.

OBJECTIVE: Current guidelines recommend the use of intraosseous access when IV access is not readily attainable. The pediatric literature reports an excellent safety profile, whereas only small prospective studies exist in the adult literature. We report a case of vasopressor extravasation and threatened limb perfusion related to intraosseous access use and our management of the complication. We further report our subsequent systematic review of intraosseous access in the adult population. DATA SOURCES: Ovid Medline was searched from 1946 to January 2015. STUDY SELECTION: Articles pertaining to intraosseous access in the adult population (age greater than or equal to 14 years) were selected. Search terms were "infusion, intraosseous" (all subfields included), and intraosseous access" as key words. DATA EXTRACTION: One author conducted the initial literature review. All authors assessed the methodological quality of the studies and consensus was used to ensure studies met inclusion criteria. DATA SYNTHESIS: The case of vasopressor extravasation was successfully treated with pharmacologic interventions, which reversed the effects of the extravasated vasopressors: intraosseous phentolamine, topical nitroglycerin ointment, and intraarterial verapamil and nitroglycerin. Our systematic review of the adult literature found 2,332 instances of intraosseous insertion. A total of 2,106 intraosseous insertion attempts were made into either the tibia or the humerus; 192 were unsuccessful, with an overall success rate of 91%. Five insertions were associated with serious complications. A total of 226 insertion attempts were made into the sternum; 54 were unsuccessful, with an overall success rate of 76%. CONCLUSIONS: Intraosseous catheter insertion provides a means for rapid delivery of medications to the vascular compartment with a favorable safety profile. Our systematic literature review of adult intraosseous access demonstrates an excellent safety profile with serious complications occurring in 0.3% of attempts. We report an event of vasopressor extravasation that was potentially limb threatening. Therapy included local treatment and injection of intraarterial vasodilators. Intraosseous access complications should continue to be reported, so that the medical community will be better equipped to treat them as they arise.

Safety of peripheral intravenous administration of vasoactive medication.

BACKGROUND: Central venous access is commonly performed to administer vasoactive medication. The administration of vasoactive medication via peripheral intravenous access is a potential method of reducing the need for central venous access. The aim of this study was to evaluate the safety of vasoactive medication administered through peripheral intravenous access. METHODS: Over a 20-month period starting in September 2012, we monitored the use of vasoactive medication via peripheral intravenous access in an 18-bed medical intensive care unit. Norepinephrine, dopamine, and phenylephrine were all approved for use through peripheral intravenous access. RESULTS: A total of 734 patients (age 72 ± 15 years, male/female 398/336, SAPS II score 75 ± 15) received vasoactive medication via peripheral intravenous access 783 times. Vasoactive medication used was norepinephrine (n = 506), dopamine (n = 101), and phenylephrine (n = 176). The duration of vasoactive medication via peripheral intravenous access was 49 ± 22 hours. Extravasation of the peripheral intravenous access during administration of vasoactive medication occurred in 19 patients (2%) without any tissue injury following treatment, with local phentolamine injection and application of local nitroglycerin paste. There were 95 patients (13%) receiving vasoactive medication through peripheral intravenous access who eventually required central intravenous access. CONCLUSIONS: Administration of norepinephrine, dopamine, or phenylephrine by peripheral intravenous access was feasible and safe in this single-center medical intensive care unit. Extravasation from the peripheral intravenous line was uncommon, and phentolamine with nitroglycerin paste were effective in preventing local ischemic injury. Clinicians should not regard the use of vasoactive medication is an automatic indication for central venous access.