Doppler identified venous congestion in septic shock: protocol for an international, multi-centre prospective cohort study (Andromeda-VEXUS)

Critical Care Ultrasonography for Volume Management: A Systematic Review, Meta-Analysis, and Trial Sequential Analysis of Randomized Trials

OBJECTIVES

To determine the safety and efficacy of critical care ultrasonography (CCUS) guided volume management in acutely ill patients.

DATA SOURCES

We searched MEDLINE, Embase, Wiley CENTRAL, and unpublished sources from inception to February 6, 2024.

STUDY SELECTION

We included randomized controlled trials (RCTs) of acutely ill adult patients randomized to receive CCUS as compared with no CCUS to guide fluid management.

DATA EXTRACTION

Reviewers screened abstracts, full texts, and extracted data independently and in duplicate. We pooled data using a random-effects model, assessed the risk of bias using the modified Cochrane tool and assessed the certainty of evidence using the Grading Recommendations Assessment, Development, and Evaluation approach.

DATA SYNTHESIS

We included 17 RCTs (n = 1765 patients) in this review. Pooled analyses found that the use of CCUS for volume management in acutely ill patients may decrease mortality at the longest reported time period (relative risk [RR], 0.79; 95% CI, 0.67-0.95; low certainty) and decreases the fluid balance up to 72 hours after admission (mean difference [MD], 0.72 L lower; 95% CI, 1.5 L lower to 0.07 L higher; low certainty). CCUS had an uncertain effect on duration of mechanical ventilation (MD, 1.14 d fewer; 95% CI, 3.35 d fewer to 1.07 d more; very low certainty), ICU length of stay (LOS) (MD, 0.01 d fewer; 95% CI, 1.12 d fewer to 1.09 d more; very low certainty), the need for vasopressors (RR, 0.39; 95% CI, 0.10-1.62; very low certainty), acute kidney injury (AKI) (RR, 0.94; 95% CI, 0.32-2.72; very low certainty), and the need for renal replacement therapy (RRT) (RR, 0.79; 95% CI, 0.17-3.66; very low certainty).

CONCLUSIONS

In acutely ill adult patients, CCUS for the use of targeted volume management may reduce mortality and fluid balance up to 72 hours after admission. CCUS has an uncertain effect on ICU LOS, duration of mechanical ventilation, duration of vasopressor use, AKI, and the need for RRT. However, this evidence is limited by imprecision and indirectness.

Demonstration of Hepatic Vein Abnormalities Using Contrast-Enhanced Sonography in Liver Diseases

Contrast-enhanced US (CEUS) is now widely used to observe the hemodynamics of the liver. The CEUS diagnosis mainly consists of evaluating hepatic artery and portal vein flow changes in liver diseases, but it has not been widely used for the diagnosis of hepatic venous (HV) abnormalities in the clinical setting. For this background, this review tried to reconsider this problem. In short, observing HV CEUS findings, especially HV transit time, serves to largely narrow the differential diagnosis and increase the diagnostic confidence of the CEUS. However, diagnosing HV CEUS diagnosis in a wide range of liver diseases requires understanding of vascular anatomy of the upper abdomen and vascular structure of each disease. Additionally, interpreting CEUS findings of HCC should be prudent, because its drainage vessels change according to the histological progression, from the HV to the portal vein. Thus, the most important way of making use of the CEUS information is interpreting it in conjunction with the clinical data.

Evaluation of a modified venous excess ultrasound (VExUS) protocol for estimation of venous congestion: a cohort study

BACKGROUND

Understanding venous congestion is critical to the management of many illnesses, but assessing volume status can be challenging. The current gold standard for volume status assessment of right heart catheterization (RHC) is invasive, costly, and often unavailable. Venous Excess Ultrasound Score (VExUS) is a novel ultrasound protocol for to assessment of venous congestion using the inferior vena cava, hepatic, portal and renal veins. Though there is a much interest in the technique, the renal component of the exam is challenging to acquire. For this reason we aimed to see if a modified VExUS (mVExUS) excluding the kidney component performs similarly to traditional VExUS (tVExUS) for detecting elevated right atrial pressure (RAP) as measured by RHC.

METHODS

A consecutive cohort of 95 patients undergoing RHC had VExUS exams before the procedure. Researchers compared the performance of tVExUS, mVExUS, and inferior vena cava (IVC) diameter in predicting RAP > 12 mmHg.

RESULTS

The area under the curve (AUC) for detecting elevated RAP was similar for tVExUS (0.87) and mVExUS (0.85). Both methods achieved high sensitivity and specificity. Agreement between tVExUS and mVExUS scores was near-perfect (Cohen's Kappa = 0.85).

CONCLUSION

mVExUS may be as effective as tVExUS in identifying elevated RAP. This abbreviated version could improve efficiency and adoption of VExUS for assessing venous congestion. Further studies are needed in diverse patient populations.

VExUS: common misconceptions, clinical use and future directions

There has been a significant interest in venous congestion in recent years, among which the VExUS score has been prominent, both in clinical practice and research efforts. We have noted some recurrent misconceptions among clinicians which are also reflected in certain research efforts. Notably, the misguided attempt to correlate VExUS to volume status, which is only one of the factors influencing it, as well as attempts to re-interpret VExUS in the context of certain pathologies, which reflects a fundamental misunderstanding of its circulatory perspective. In this article we review the physiological basis of the VExUS assessment as a measure and marker of venous congestion from the organs' standpoint and its role as part of the emerging concept of fluid tolerance, in hopes to address these misconceptions for clinicians and for important further studies.

Point-of-Care Ultrasound: A Vital Tool for Anesthesiologists in the Perioperative and Critical Care Settings

Point-of-care ultrasound (POCUS) is an essential skill in various specialties like anesthesiology, critical care, and emergency medicine. Anesthesiologists utilize POCUS for quick diagnosis and procedural guidance in perioperative and critical care settings. Key applications include vascular ultrasound for challenging venous and arterial catheter placements, gastric ultrasound for aspiration risk assessment, airway ultrasound, diaphragm ultrasound, and lung ultrasound for respiratory assessment. Additional utilities of POCUS can include multi-organ POCUS evaluation for undifferentiated shock or cardiac arrest, ultrasound-guided central neuraxial and peripheral nerve blocks, focused cardiac ultrasound, and novel applications such as venous excess ultrasound. This review highlights these POCUS applications in perioperative and intensive care and summarizes the latest evidence of their accuracy and limitations.

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.

Hemodynamic Support in Sepsis

This review discusses recent evidence in managing sepsis-induced hemodynamic alterations and how it can be integrated with previous knowledge for actionable interventions in adult patients.

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.

Coexistence of a fluid responsive state and venous congestion signals in critically ill patients: a multicenter observational proof-of-concept study

BACKGROUND

Current recommendations support guiding fluid resuscitation through the assessment of fluid responsiveness. Recently, the concept of fluid tolerance and the prevention of venous congestion (VC) have emerged as relevant aspects to be considered to avoid potentially deleterious side effects of fluid resuscitation. However, there is paucity of data on the relationship of fluid responsiveness and VC. This study aims to compare the prevalence of venous congestion in fluid responsive and fluid unresponsive critically ill patients after intensive care (ICU) admission.

METHODS

Multicenter, prospective cross-sectional observational study conducted in three medical-surgical ICUs in Chile. Consecutive mechanically ventilated patients that required vasopressors and admitted < 24 h to ICU were included between November 2022 and June 2023. Patients were assessed simultaneously for fluid responsiveness and VC at a single timepoint. Fluid responsiveness status, VC signals such as central venous pressure, estimation of left ventricular filling pressures, lung, and abdominal ultrasound congestion indexes and relevant clinical data were collected.

RESULTS

Ninety patients were included. Median age was 63 [45-71] years old, and median SOFA score was 9 [7-11]. Thirty-eight percent of the patients were fluid responsive (FR+), while 62% were fluid unresponsive (FR-). The most prevalent diagnosis was sepsis (41%) followed by respiratory failure (22%). The prevalence of at least one VC signal was not significantly different between FR+ and FR- groups (53% vs. 57%, p = 0.69), as well as the proportion of patients with 2 or 3 VC signals (15% vs. 21%, p = 0.4). We found no association between fluid balance, CRT status, or diagnostic group and the presence of VC signals.

CONCLUSIONS

Venous congestion signals were prevalent in both fluid responsive and unresponsive critically ill patients. The presence of venous congestion was not associated with fluid balance or diagnostic group. Further studies should assess the clinical relevance of these results and their potential impact on resuscitation and monitoring practices.

Challenges in Septic Shock: From New Hemodynamics to Blood Purification Therapies

Sepsis and septic shock are associated with high mortality, with diagnosis and treatment remaining a challenge for clinicians. Their management classically encompasses hemodynamic resuscitation, antibiotic treatment, life support, and focus control; however, there are aspects that have changed. This narrative review highlights current and avant-garde methods of handling patients experiencing septic shock based on the experience of its authors and the best available evidence in a context of uncertainty. Following the first recommendation of the Surviving Sepsis Campaign guidelines, it is recommended that specific sepsis care performance improvement programs are implemented in hospitals, i.e., "Sepsis Code" programs, designed ad hoc, to achieve this goal. Regarding hemodynamics, the importance of perfusion and hemodynamic coherence stand out, which allow for the recognition of different phenotypes, determination of the ideal time for commencing vasopressor treatment, and the appropriate fluid therapy dosage. At present, this is not only important for the initial timing, but also for de-resuscitation, which involves the early weaning of support therapies, directed elimination of fluids, and fluid tolerance concept. Finally, regarding blood purification therapies, those aimed at eliminating endotoxins and cytokines are attractive in the early management of patients in septic shock.

Fluid Status Assessment in Critically Ill Patients with COVID-19: A Retrospective Cohort Study

Fluid status (FS) is a diagnostic challenge in critically ill patients with COVID-19. Here, we compared parameters related to FS derived from cumulative fluid balance (CFB), bioelectrical impedance analysis (BIA) and venous congestion assessed by ultrasound (VExUS) to predict mortality. We retrospectively reviewed the medical records of individuals with severe pneumonia due to COVID-19 between July and November 2021 in a single center. Comorbidities, demographic, clinical and laboratory data as well as results from CFB, BIA and VExUS measurements were collected on admission and weekly afterwards for two consecutive evaluations. Seventy-nine patients were included, of which eighteen (14.2%) died. Abnormalities of FS were only identified by BIA. Extracellular water/total body water ratio (ECW/TBW) > 0.394 (overhydrated) by BIA was a good predictor of mortality (AUC = 0.78, 95% CI: 0.067-0.89). Mortality risk was higher in overhydrated patients (OR: 6.2, 95% CI: 1.2-32.6, p = 0.02) and in persistently overhydrated patients (OR: 9.57, 95% CI: 1.18-77.5, p = 0.03) even after adjustment to age, serum albumin and acute kidney injury (AKI) in stages 2-3. Time to death was shorter in overhydrated patients (HR: 2.82, 95% CI: 1.05-7.5, log-rank test p = 0.03). Abnormalities in FS associated with mortality were only identified by BIA in critically ill patients with COVID-19.