Monitoring the venous circulation: novel techniques and applications.

PURPOSE OF REVIEW: Venous pressure is an often-unrecognized cause of patient morbidity. However, bedside assessment of PV is challenging. We review the clinical significance of venous pressure measurement, existing techniques, and introduce the Venous Excess Ultrasound (VExUS) Score as a novel approach using doppler ultrasound to assess venous pressure. RECENT FINDINGS: Studies show clear associations between elevated venous pressure and adverse outcomes in critically ill patients. Current venous pressure measurement techniques include physical examination, right heart catheterization (RHC), two-dimensional ultrasound, and a variety of labor-intensive research-focused physiological maneuvers. Each of these techniques have specific shortcomings, limiting their clinical utility. To address these gaps, Beaubien-Souligny et al. introduced the VExUS Score, a novel doppler ultrasound-based method that integrates IVC diameter with doppler measurements of the hepatic, portal, and renal veins to generate a venous congestion assesment. Studies show strong correlations between VExUS score and RHC measurements, and well as an association between VExUS score and improvement in cardiorenal acute kidney injury, diuretic response, and fluid status shifts. However, studies in noncardiac populations have been small, heterogenous, and inconclusive. SUMMARY: Early studies evaluating the use of doppler ultrasound to assess venous congestion show promise, but further research is needed in diverse patient populations and clinical settings.

Reduced mortality associated with pulmonary embolism response team consultation for intermediate and high-risk pulmonary embolism: a retrospective cohort study.

BACKGROUND: The management of acute pulmonary embolism (PE) has become increasingly complex with the expansion of advanced therapeutic options, resulting in the development and widespread adoption of multidisciplinary Pulmonary Embolism Response Teams (PERTs). Much of the literature evaluating the impact of PERTs has been limited by pre- postimplementation study design, leading to confounding by changes in global practice patterns over time, and has yielded mixed results. To address this ambiguity, we conducted a retrospective cohort study to evaluate the impact of the distinct exposures of PERT availability and direct PERT consultation. METHODS: At a single tertiary center, we conducted propensity-matched analyses of hospitalized patients with intermediate or high-risk PE. To assess the impact of PERT availability, we evaluated the changes in 30-day mortality, hospital length of stay (HLOS), time to therapeutic anticoagulation (TAC), in-hospital bleeding complications, and use of advanced therapies between the two years preceding and following PERT implementation. To evaluate the impact of direct PERT consultation, we conducted the same analyses in the post-PERT era, comparing patients who did and did not receive PERT consultation. RESULTS: Six hundred eighty four patients were included, of which 315 were pre-PERT patients. Of the 367 postPERT patients, 201 received PERT consultation. For patients who received PERT consultation, we observed a significant reduction in 30-day mortality (5% vs 20%, OR 0.38, p = 0.0024), HLOS. (-5.4 days, p < 0.001), TAC (-0.25 h, p = 0.041), and in-hospital bleeding (OR 0.28, p = 0.011). These differences were not observed evaluating the impact of PERT presence in pre-vs postimplementation eras. CONCLUSIONS: We observed a significant reduction in 30-day mortality, hospital LOS, TAC, and in-hospital bleeding complications for patients who received PERT consultation without an observed difference in these metrics when comparing the pre- vs post-implementation eras. This suggests the benefits stem from direct PERT involvement rather than the mere existence of PERT. Our data supports that PERT consultation may provide benefit to patients with acute intermediate or high-risk PE and can be achieved without a concomitant increase in advanced therapies.

Reliability and reproducibility of the venous excess ultrasound (VExUS) score, a multi-site prospective study: validating a novel ultrasound technique for comprehensive assessment of venous congestion.

Though the novel venous excess ultrasound (VExUS) score is increasingly used as a noninvasive means of venous congestion measurement, the inter-rater reliability (IRR), inter-user reproducibility (IUR), and utility of concurrent ECG have not been evaluated. We conducted a multicenter study of the IRR, IUR, and utility of ECG for VExUS interpretation between four attending physicians of diverse specialties, reporting the Kappa statistic (KS) and Intraclass Correlation Coefficient (ICC) for IRR and IUR for scans with and without ECG. Eighty-four paired VExUS exams from 42 patients, 60 of which had a concurrent ECG tracing, were interpreted. They showed substantial IRR, with a KS of 0.71 and ICC of 0.83 for the overall VExUS grade (p < 0.001), and IUR, with a KS 0.63 and ICC of 0.8. There was greater agreement among images with an ECG tracing. These results suggest that ECG-augmented VExUS may be a reliable and reproducible measure interpretable by clinicians with diverse backgrounds.

Correlation between the VExUS score and right atrial pressure: a pilot prospective observational study.

Venous congestion is an under-recognized contributor to mortality in critically ill patients. Unfortunately, venous congestion is difficult to measure, and right heart catheterization (RHC) has been considered the most readily available means for measuring venous filling pressure. Recently, a novel "Venous Excess Ultrasound (VExUS)" score was developed to noninvasively quantify venous congestion using inferior vena cava (IVC) diameter and Doppler flow through the hepatic, portal, and renal veins. A preliminary retrospective study of post-cardiac surgery patients showed promising results, including a high positive-likelihood ratio of high VExUS grade for acute kidney injury. However, studies have not been reported in broader patient populations, and the relationship between VExUS and conventional measures of venous congestion is unknown. To address these gaps, we prospectively assessed the correlation of VExUS with right atrial pressure (RAP), with comparison to inferior vena cava (IVC) diameter. Patients undergoing RHC at Denver Health Medical Center underwent VExUS examination before their procedure. VExUS grades were assigned before RHC, blinding ultrasonographers to RHC outcomes. After controlling for age, sex, and common comorbidities, we observed a significant positive association between RAP and VExUS grade (P < 0.001, R2 = .68). VExUS had a favorable AUC for prediction of a RAP ≥ 12 mmHg (0.99, 95% CI 0.96-1) compared to IVC diameter (0.79, 95% CI 0.65-0.92). These results suggest a strong correlation between VExUS and RAP in a diverse patient population, and support future studies of VExUS as a tool to assess venous congestion and guide management in a spectrum of critical illnesses.

Increasing PrEP uptake and adherence among MSM and TW sex workers in Lima, Perú: what and whom do different patients trust?

In Perú, men who have sex with men (MSM) and transgender women (TW) suffer rates of HIV 50 times greater than the general population. MSM or TW sex workers (SWs) are at especially high risk. Daily oral pre-exposure prophylaxis (PrEP) effectively prevents HIV infection if patients adhere to a daily or on-demand regimen. Necessary levels of adoption and adherence require data-driven intervention strategies for these marginalized groups. We conducted qualitative content analysis of data obtained from focus groups (FGs) with MSM and TW SWs. Both groups expressed strong skepticism about the motives behind international drug trials, and the safety of participating in them. Important differences between MSM and TW groups' beliefs about trustworthy information as well as community and public institutions also emerged. MSM SWs were less trusting of information from other MSM SWs, and preferred to receive information from institutional medical sources, while TGW SWs preferred to receive information from other TGW SWs. Successful strategies to encourage PrEP uptake and adherence must address the distrust patients feel towards international and institutional actors by providing patients with tailored, reliable information from local and community sources that they trust.

Prospective Evaluation of Venous Excess Ultrasound for Estimation of Venous Congestion.

BACKGROUND: Venous excess ultrasound (VExUS) is a novel ultrasound technique previously reported as a noninvasive measure of venous congestion and predictor of cardiorenal acute kidney injury. RESEARCH QUESTION: Are there associations between VExUS grade and cardiac pressures measured by right heart catheterization (RHC) and cardiac biomarkers and clinical outcomes in patients undergoing RHC? STUDY DESIGN AND METHODS: We conducted a prospective cohort study at the Denver Health Medical Center from December 20, 2022, to March 25, 2023. All patients undergoing RHC underwent a blinded VExUS assessment prior to their procedure. Multivariable regressions were conducted to assess relationships between VExUS grade and cardiac pressures, biomarkers, and changes in weight among patients with heart failure, a proxy for diuretic success. Receiver operating characteristic curve and area under the curve (AUC) were derived for VExUS, inferior vena cava (IVC) diameter, and IVC collapsibility index (ICI) to predict right atrial pressure (RAP) > 10 and < 7 mm Hg. RESULTS: Among 81 patients, 45 of whom were inpatients, after adjusting for age, sex, and Charlson Comorbidity Index, there were significant relationships between VexUS grade of 2 (ß = 4.8; 95% CI, 2.6-7.1; P < .01) and 3 (ß = 11; 95% CI, 8.9-14; P < .01) and RAP, VExUS grade of 2 (ß = 6.8; 95% CI, 0.16-13; P = .045) and 3 (ß = 15; 95% CI, 7.3-22; P < .01) and mean pulmonary artery pressure, and VExUS grade of 2 (ß = 7.0; 95% CI, 3.9-10; P < .01) and 3 (ß = 13; 95% CI, 9.5-17; P < .01) and pulmonary capillary wedge pressure. AUC values for VExUS, IVC diameter, and ICI as predictors of RAP > 10 mm Hg were 0.9 (95% CI, 0.83-0.97), 0.77 (95% CI, 0.68-0.88), and 0.65 (95% CI, 0.52-0.78), respectively. AUC values for VExUS, IVC diameter, and ICI as predictors of RAP < 7 mm Hg were 0.79 (95% CI, 0.70-0.87), 0.74 (95% CI, 0.64-0.84), and 0.62 (95% CI, 0.49-0.76), respectively. In a subset of 23 patients with heart failure undergoing diuresis, there was a significant association between VExUS grade 3 and change in weight between time of RHC and discharge (P = .025). INTERPRETATION: Although more research is required, VExUS has the potential to increase diagnostic and therapeutic capabilities of physicians at the bedside and increase our understanding of the underappreciated problem of venous congestion.

Venous excess ultrasonography (VExUS) captures dynamic changes in volume status surrounding hemodialysis: A multicenter prospective observational study.

Background: The evaluation of volume status is essential to clinical decision-making, yet multiple studies have shown that physical exam does not reliably estimate a patient's intravascular volume. Venous excess ultrasound score (VExUS) is an emerging volume assessment tool that utilizes inferior vena cava (IVC) diameter and pulse-wave Doppler waveforms of the portal, hepatic and renal veins to evaluate venous congestion. A point-of-care ultrasound exam initially developed by Beaubein-Souligny et al., VExUS represents a reproducible, non-invasive and accurate means of assessing intravascular congestion. VExUS has recently been validated against RHC-the gold-standard of hemodynamic evaluation for volume assessment. While VExUS scores were shown to correlate with elevated cardiac filling pressures (i.e., right atrial pressure (RAP) and pulmonary capillary wedge pressure (PCWP)) at a static point in time, the ability of VExUS to capture dynamic changes in volume status has yet to be elucidated. We hypothesized that paired VExUS examinations performed before and after hemodialysis (HD) would reflect changes in venous congestion in a diverse patient population. Methods: Inpatients with end-stage renal disease undergoing intermittent HD were evaluated with transabdominal VExUS and lung ultrasonography before and following HD. Paired t-tests were conducted to assess differences between pre-HD and post-HD VExUS scores, B-line scores and dyspnea scores. Results: Fifty-six patients were screened for inclusion in this study. Ten were excluded due to insufficient image quality or incomplete exams, and forty-six patients (ninety-two paired ultrasound exams) were included in the final analysis. Paired t-test analysis of pre-HD and post-HD VExUS scores revealed a mean VExUS grade change of 0.82 (p<0.001) on a VExUS scale ranging from 0 to 4. The mean difference in B-line score following HD was 0.8 (p=0.001). There was no statistically significant difference in subjective dyspnea score (p=0.41). Conclusions: Large-volume fluid removal with HD was represented by changes in VExUS score, highlighting the utility of the VExUS exam to capture dynamic shifts in intravascular volume status. Future studies should evaluate change in VExUS grade with intravenous fluid or diuretic administration, with the ultimate goal of evaluating the capacity of a standardized bedside ultrasound protocol to guide inpatient volume optimization.

A Quality Improvement Approach to Modification of a Point-of-Care Ultrasound Curriculum.

Background: There is increasing emphasis on resident involvement in quality improvement (QI) efforts, yet resident engagement in QI has remained low for many reasons. Although QI methods are classically applied to clinical processes, there are many opportunities to incorporate QI principles into curricular design and implementation. Objective: Demonstrate the utility of QI methods when applied to curricular design and the implementation of a novel point-of-care ultrasound portfolio development and quality assurance program at a large internal medicine residency program. Methods: We applied foundational QI methods, including process mapping, plan-do-study-act (PDSA) cycles, time-trap identification, run-chart analysis, and qualitative interviews throughout the curricular design and implementation phases to rapidly identify areas for improvement and perform timely tests of change. Results: Fifty-one interns participated in the curriculum, submitting 731 images in the first trimester. Process mapping and submission review revealed that 29% of images were saved to the incorrect digital archive. Resident-reviewer interpretation concordance was present in 80.7% of submissions. In 95.2% of completed quality assurance cards, the same information was provided in the commentary feedback and the evaluator's checklists, representing a time trap. Interventions included restricting access to image archives and removing redundant fields from quality assurance cards. The time to feedback fell from 69.5 to 6.5 days, demonstrating nonrandom variation via run-chart analysis. Conclusion: This pilot study demonstrates the successful application of QI methods to a novel point-of-care ultrasound curriculum. The systematic use of these methodologies in curricular design and implementation allows expeditious curricular improvement. Emphasizing the relevance of QI methods to subject matter beyond clinical processes may increase resident engagement in QI efforts.

HIV Disease Dynamics and Markers of Inflammation and CNS Injury During Primary HIV Infection and Their Relationship to Cognitive Performance.

INTRODUCTION: Early systemic and central nervous system viral replication and inflammation may affect brain integrity in people with HIV, leading to chronic cognitive symptoms not fully reversed by antiretroviral therapy (ART). This study examined associations between cognitive performance and markers of CNS injury associated with acute HIV infection and ART. METHODS: HIV-infected MSM and transgender women (average age: 27 years and education: 13 years) enrolled within 100 days from the estimated date of detectable infection (EDDI). A cognitive performance (NP) protocol was administered at enrollment (before ART initiation) and every 24 weeks until week 192. An overall index of cognitive performance (NPZ) was created using local normative data. Blood (n = 87) and cerebrospinal fluid (CSF; n = 29) biomarkers of inflammation and neuronal injury were examined before ART initiation. Regression analyses assessed relationships between time since EDDI, pre-ART biomarkers, and NPZ. RESULTS: Adjusting for multiple comparisons, shorter time since EDDI was associated with higher pre-ART VL and multiple biomarkers in plasma and CSF. NPZ scores were within the normative range at baseline (NPZ = 0.52) and at each follow-up visit, with a modest increase through week 192. Plasma or CSF biomarkers were not correlated with NP scores at baseline or after ART. CONCLUSIONS: Biomarkers of CNS inflammation, immune activation, and neuronal injury peak early and then decline during acute HIV infection, confirming and extending results of other studies. Neither plasma nor CSF biomarkers during acute infection corresponded to NP scores before or after sustained ART in this cohort with few psychosocial risk factors for cognitive impairment.

Development of a Single-Institution Virtual Internal Medicine Subinternship With Near-Peer Teaching in Response to the COVID-19 Pandemic.

PROBLEM: In March 2020, medical students at the University of Washington School of Medicine were removed from clinical settings in response to the COVID-19 pandemic. As subinternships are required for graduation and an important way to prepare for internship, a virtual subinternship was created to include practical elements of in-person learning and to address limited teaching faculty from COVID-19 inpatient surges. APPROACH: A virtual, interactive subinternship was developed with case-based teaching sessions, communication and critical literature evaluation skill building, professional development, and creation of independent learning plans. Near-peer teachers (NPTs) were selected from graduating senior medical students who matched into internal medicine. In addition to teaching topics from the Clerkship Directors of Internal Medicine curriculum, NPTs engaged in course development, recruited teaching faculty, gathered feedback, and facilitated small groups. Participating students completed pre- and postcourse surveys. OUTCOMES: The 10 students (100%) enrolled in the course who completed both surveys indicated significant improvement in mean scores across 4 domains: evaluating medical literature (3.1/5 to 4.5/5; +1.4, P < .001); developing individual learning plans (3.6/5 to 4.7/5; +1.1, P = .001); perceived ability to efficiently evaluate patients with common internal medicine concerns (3.7/5 to 4.6/5; +0.9, P = .004); and formulating initial diagnostic and therapeutic plans (3.6/5 to 4.6/5; +1.0, P < .001). Themes extracted from open-ended responses included initial skepticism of an online format, the course exceeding expectations, and feeling prepared for internship. NEXT STEPS: Although a virtual subinternship lacks direct patient care, students reported improvement in all 4 domains studied. Future courses would benefit from greater use of simulation and role-playing scenarios for practical skills. The experience with NPTs was encouraging, aiding in the success of the subinternship. The role of NPTs should be cultivated to fill gaps in content delivery and enhance the development of students as educators.

Respiratory Mechanics in a Cohort of Critically Ill Subjects With COVID-19 Infection.

BACKGROUND: Patients with coronavirus disease 2019 (COVID-19) often develop acute hypoxemic respiratory failure and receive invasive mechanical ventilation. Much remains unknown about their respiratory mechanics, including the trajectories of pulmonary compliance and [Formula: see text]/[Formula: see text], the prognostic value of these parameters, and the effects of prone positioning. We described respiratory mechanics among subjects with COVID-19 who were intubated during the first month of hospitalization. METHODS: We included patients with COVID-19 who were mechanically ventilated between February and May 2020. Daily values of pulmonary compliance, [Formula: see text], [Formula: see text], and the use of prone positioning were abstracted from electronic medical records. The trends were analyzed separately over days 1-10 and days 1-35 of intubation, stratified by prone positioning use, survival, and initial [Formula: see text]/[Formula: see text]. RESULTS: Among 49 subjects on mechanical ventilation day 1, the mean compliance was 41 mL/cm H2O, decreasing to 25 mL/cm H2O by day 14, the median duration of mechanical ventilation. In contrast, the [Formula: see text]/[Formula: see text] on day 1 was similar to day 14. The overall mean compliance was greater among the non-survivors versus the survivors (27 mL/cm H2O vs 24 mL/cm H2O; P = .005), whereas [Formula: see text]/[Formula: see text] was higher among the survivors versus the non-survivors over days 1-10 (159 mm Hg vs 138 mm Hg; P = .002) and days 1-35 (175 mm Hg vs 153 mm Hg; P < .001). The subjects who underwent early prone positioning had lower compliance during days 1-10 (27 mL/cm H2O vs 33 mL/cm H2O; P < .001) and lower [Formula: see text]/[Formula: see text] values over days 1-10 (139.9 mm Hg vs 167.4 mm Hg; P < .001) versus those who did not undergo prone positioning. After day 21 of hospitalization, the average compliance of the subjects who had early prone positioning surpassed that of the subjects who did not have prone positioning. CONCLUSIONS: Respiratory mechanics of the subjects with COVID-19 who were on mechanical ventilation were characterized by persistently low respiratory system compliance and [Formula: see text]/[Formula: see text], similar to ARDS due to other etiologies. The [Formula: see text]/[Formula: see text] was more tightly associated with mortality than with compliance.

Emergency department characteristics and associations with intensive care admission among patients with coronavirus disease 2019.

OBJECTIVE: There have been few descriptions in the literature to date specifically examining initial coronavirus disease 2019 (COVID-19) patient presentation to the emergency department (ED) and the trajectory of patients who develop critical illness. Here we describe the ED presentation and outcomes of patients with COVID-19 presenting during our initial local surge. METHODS: This is a multicenter, retrospective cohort study using data extracted from the electronic health records at 3 hospitals within a single health system from March 1, 2020 to June 1, 2020. Patients were included in the study if they presented to an ED and had laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection during the study period. Data elements were extracted from the electronic health record electronically and by trained data abstractors and entered into a secure database. We used multivariable regression analysis to examine ED factors associated with the development of critical illness and mortality, with a primary outcome of ICU admission. RESULTS: A total of 330 patients with laboratory-confirmed SARS-CoV-2 infection were admitted during the study period. Of these, 112 (34%) were admitted to the ICU. Among these patients, 20% were female, 50% were White, the median age was 61 (interquartile range [IQR], 52-72), and the median body mass index (BMI) was 28.1 (IQR, 24.3-35.1). On univariable analysis, a doubling of lactate dehydrogenase (LDH) (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.40-6.27) or high-sensitivity C-reactive protein (hsCRP; OR, 1.32; 95% CI, 1.11-1.57) above the reference range or elevated troponin (OR, 12.1; 95% CI, 1.20-121.8) were associated with ICU admission. After adjusting for age, sex, and BMI, LDH was the best predictor of ICU admission (OR, 3.54; 95% CI, 2.12-5.90). Of the patients, 15% required invasive mechanical ventilation during their hospital course, and in-hospital mortality was 19%. CONCLUSIONS: Nearly one-third of ED patients who required hospitalization for COVID-19 were admitted to the ICU, 15% received invasive mechanical ventilation, and 19% died. Most patients who were admitted from the ED were tachypneic with elevated inflammatory markers, and the following factors were associated with ICU admission: elevated hsCRP, LDH, and troponin as well as lower oxygen saturation and increased respiratory rate.

Virtual Peer Teaching During the COVID-19 Pandemic.

Virtual peer teaching can be part of the solution to challenges in medical education during the pandemic. We developed an online clinician teacher elective, implemented virtual peer teaching throughout our curriculum, and believe it benefits students, peer teachers, and faculty. We plan to continue virtual peer teaching beyond the pandemic.

Metagenomic identification of active methanogens and methanotrophs in serpentinite springs of the Voltri Massif, Italy.

The production of hydrogen and methane by geochemical reactions associated with the serpentinization of ultramafic rocks can potentially support subsurface microbial ecosystems independent of the photosynthetic biosphere. Methanogenic and methanotrophic microorganisms are abundant in marine hydrothermal systems heavily influenced by serpentinization, but evidence for methane-cycling archaea and bacteria in continental serpentinite springs has been limited. This report provides metagenomic and experimental evidence for active methanogenesis and methanotrophy by microbial communities in serpentinite springs of the Voltri Massif, Italy. Methanogens belonging to family Methanobacteriaceae and methanotrophic bacteria belonging to family Methylococcaceae were heavily enriched in three ultrabasic springs (pH 12). Metagenomic data also suggest the potential for hydrogen oxidation, hydrogen production, carbon fixation, fermentation, and organic acid metabolism in the ultrabasic springs. The predicted metabolic capabilities are consistent with an active subsurface ecosystem supported by energy and carbon liberated by geochemical reactions within the serpentinite rocks of the Voltri Massif.