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.

Agitated Saline Contrast Injection in Patients with Severe Hypoxemia.

The use of agitated saline contrast (ASC) during echocardiographic examinations is a well-established practice, most commonly performed to identify atrial septal abnormalities in the context of stroke. In the intensive care unit, this technique may be employed to identify anatomic right-to-left shunts (either intracardiac or transpulmonary) that may be contributing to hypoxemic respiratory failure. This narrative review will describe the technique of ASC injection, summarize clinical scenarios where it may be useful, and review the strengths and limitations of the tool.

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.

The impact of different CPAP delivery approaches on nightly adherence and discontinuation rate in patients with obstructive sleep apnea.

STUDY OBJECTIVES: The impact of direct mail order sales of positive airway pressure (PAP) devices, accentuated by the coronavirus disease 2019 (COVID-19) pandemic, on PAP adherence in patients with obstructive sleep apnea remains unclear. In this study we compared the impact of different modes of continuous positive airway pressure delivery on adherence and daytime symptoms. We hypothesized that adherence would not be affected by remote PAP setup, aided by telehealth technology. METHODS: Three groups were studied: 1) standard group PAP setup (3-4 people); 2) direct home shipment of PAP, followed by telehealth interactions; 3) direct home shipment of PAP, during the COVID-19 pandemic where delivery choice was removed. Demographics, sleepiness, PAP data, and insurance information were also compared. RESULTS: A total of 666 patients were studied in 3 groups. 1) Standard group PAP setup had 225 patients and adherence with PAP (% of nights used more than 4 hours) was 65.3 ± 2.1%. 2) Direct home shipment of PAP group had 231 patients, and adherence was 54.2 ± 2.4%. 3) Direct mailed PAP units during the COVID-19 pandemic group had 210 patients, and adherence was 55.9 ± 2.5%. Adherence was lower in both groups receiving home shipments compared to those in groups in-center (analysis of variance, Tukey, P = .002). Discontinuation of PAP was less in the in-center group setup patients (χ2 = 10.938 P ≤ .001). CONCLUSIONS: Patients receiving direct home PAP shipments had lower adherence and were more likely to discontinue PAP compared to standard in-person setup. CITATION: Stanchina M, Lincoln J, Prenda S, et al. The impact of different CPAP delivery approaches on nightly adherence and discontinuation rate in patients with obstructive sleep apnea. J Clin Sleep Med. 2022;18(8):2023-2027.

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.

Hemoglobin Target and Transfusion Modality for Adult Patients With Sickle Cell Disease Acute Chest Syndrome.

BACKGROUND: Despite the importance of transfusion in treating sickle cell disease acute chest syndrome, the target hemoglobin and optimal modality for transfusion remain unknown. OBJECTIVES: To compare hospital length of stay (LOS) in intensive care unit (ICU) patients with acute chest syndrome transfused to hemoglobin ≥ 8 g/dL versus patients transfused to hemoglobin < 8 g/dL; and to compare hospital LOS in acute chest syndrome patients treated with and without exchange transfusion. METHODS: We performed a retrospective cohort study of all acute chest syndrome patients treated in the medical ICU at 2 tertiary care hospitals between January 2011 and August 2016 (n = 82). We compared median hospital LOS in patients transfused to hemoglobin ≥ 8 g/dL by the time of ICU transfer to the medical floor versus patients transfused to hemoglobin < 8 g/dL as well as patients who received exchange transfusion versus no exchange transfusion using Wilcoxon rank-sum tests. We modeled the association between hospital LOS and hemoglobin at ICU transfer to the medical floor using multivariable log-linear regression. RESULTS: Median hospital LOS was about half as long for patients transfused to hemoglobin ≥ 8 g/dL versus hemoglobin < 8 g/dL (8.0 versus 16.5 days, P = 0.008). There was no difference in LOS for patients treated with and without exchange transfusion. On average, a 1 g/dL increase in hemoglobin was associated with a 19.5% decrease (95% CI 10.8-28.2%) in LOS, controlling for possible confounding factors. CONCLUSIONS: Transfusion to a hemoglobin target ≥ 8 g/dL is associated with decreased hospital LOS in patients with acute chest syndrome. There was no difference in LOS between patients who received exchange transfusion and those who did not.

Risks and Benefits of Fluid Administration as Assessed by Ultrasound.

For patients in shock, decisions regarding administering or withholding IV fluids are both difficult and important. Although a strategy of relatively liberal fluid administration has traditionally been popular, recent trial results suggest that moving to a more fluid-restrictive approach may be prudent. The goal of this article was to outline how whole-body point-of-care ultrasound can help clarify both the possible benefits and the potential risks of fluid administration, aiding in the risk/benefit calculations that should always accompany fluid-related decisions.

Ultrasound Assessment of the Inferior Vena Cava for Fluid Responsiveness: Making the Case for Skepticism.

Determining whether a patient in shock is in a state of fluid responsiveness (FR) has long been the Holy Grail for clinicians who care for acutely ill patients. While various tools have been put forth as solutions to this important problem, ultrasound assessment of the inferior vena cava has received particular attention of late. Dozens of studies have examined its ability to determine whether a patient should receive volume expansion, and general enthusiasm has been strengthened by the fact that it is easy to perform and non-invasive, unlike many competing FR tests. A deeper examination of the technique, however, reveals important concerns regarding inaccuracies in measurement and a high prevalence of confounding factors. Furthermore, a detailed review of the evidence (small individual studies, multiple meta-analyses, and a single large trial) reveals that the tool performs poorly in general and is unlikely to be helpful at the bedside in circumstances where genuine clinical uncertainty exists.

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.

Point-of-care lung ultrasound patterns in late third-trimester gravidas with and without preeclampsia.

BACKGROUND: Transthoracic point-of-care ultrasonography of the lungs has become a standard technique in critical care medicine for the evaluation of patients with respiratory signs or symptoms but has not been well studied in pregnancy. OBJECTIVE: To compare lung ultrasound patterns in third-trimester gravidas with and without preeclampsia and assess interobserver agreement between 3 obstetrical providers and a physician expert in critical care lung ultrasound. STUDY DESIGN: This is a prospective observational study of 262 women with singleton pregnancies between 32 0/7 and 41 6/7 weeks' gestation. Lung ultrasound examinations were performed and interpreted by a team of obstetrical care providers and then interpreted by an expert in point-of-care lung ultrasound. The number of B-lines in each of the 4 lung fields, indicating the accumulation of fluid in the interstitial space and the alveoli, was evaluated. The primary outcome was a positive study for pulmonary interstitial edema, defined as an ultrasound study with 3 or more B-lines in 2 or more bilateral lung fields. The secondary outcome was a lung ultrasound study with 1 or 2 B-lines in 1 or more lung fields or 3 B-lines in 1 lung field. Interobserver agreement in lung ultrasound interpretation between obstetrical care providers and an expert in critical care point-of-care ultrasonography of the lung was assessed. RESULTS: Among healthy gravidas, no subject had a lung ultrasound examination positive for pulmonary interstitial edema. Notably, 2 patients with preeclampsia had positive lung ultrasound studies, and both had respiratory symptoms or signs of pulmonary edema. One or 2 B-lines or 3 B-lines in 1 lung field were identified in 11.4% of healthy gravidas and 18.6% of patients with preeclampsia. There was no difference in lung ultrasound patterns between healthy gravidas and those with preeclampsia. The obstetrical care providers and the lung ultrasound expert had a high proportion of agreement regarding the interpretation of negative lung ultrasound examinations. The 2 patients with clinical signs of pulmonary edema were judged to have positive studies by both the obstetrical team and the expert; however, the obstetrical team classified more studies as positive. CONCLUSION: Lung ultrasound patterns in women with preeclampsia without respiratory symptoms or clinical signs of pulmonary edema are similar to the lung ultrasound patterns of healthy gravidas. Point-of-care lung ultrasound can be used to evaluate third-trimester gravidas with preeclampsia and respiratory complaints or signs concerning for pulmonary edema. Formal training is important before the widespread adoption of point-of-care lung ultrasound by obstetrical healthcare providers.

Lung Ultrasound for Patients With Coronavirus Disease 2019 Pulmonary Disease.

Given the general utility of lung ultrasound for the evaluation of respiratory failure in acutely ill patients, it is logical to consider its specific advantages in coronavirus disease 2019-related pulmonary disease. The authors, representing the extensive experience of the North American and European coronavirus disease 2019 epicenters, present an ultrasound scanning protocol and report on the common associated ultrasound findings.