The utility of point-of-care ultrasound in the assessment of volume status in acute and critically ill patients

Assessment of Fluid Responsiveness via Central Venous Ultrasound Measurement: A Network Meta-Analysis

Background: Ultrasonographic assessment of the diameters of various veins and their indices are among the most applied diagnostic tools for evaluating fluid responsiveness in clinical practice. Despite their widespread use, there is no definitive answer on which is preferable. Our study aimed to investigate the diagnostic accuracy of different venous diameters and their indices to assess fluid responsiveness. Methods: We conducted a systematic review and network meta-analysis, analyzing prospective studies evaluating the diagnostic accuracy of venous diameters (inferior vena cava [IVC], internal jugular vein [IJV], superior vena cava, and subclavian vena) and their indices for fluid responsiveness. Electronic databases were searched from inception until March 2024; this search was supplemented by snowballing methods. The risk of bias was evaluated with QUADAS-2, and evidence certainty was assessed using the GRADE approach. Nine prospective cohort studies (560 patients) were included. Results: The network meta-analysis revealed that the ΔCaval index exhibited a significant performance advantage over other "venous" test parameters. The caval index significantly outperformed IJV min/max and IVCmax. IJV index and IVCmin significantly outperformed IJVmin/max. The caval index was comparable to the IJV index. The caval index was comparable during mechanical ventilation and spontaneous breathing. Conclusions: In this meta-analysis, the ΔCaval index test showed higher diagnostic accuracy for fluid responsiveness compared with other venous tests. Caval and jugular indices displayed similar accuracy, and caval indices were consistent under mechanical ventilation and spontaneous breathing. Indices generally outperformed absolute values, except for IVCmin, which equaled the caval index in efficacy. This study was registered on the International Platform for Registered Protocols for Systematic Reviews and Meta-Analyses: INPLASY202430104.

Ultrasonographic Evaluation of Hypervolemic and Normovolemic Patients: A Comparison of Inferior Vena Cava, Subclavian Vein, Internal Jugular Vein, and Femoral Vein Diameters and Collapsibility Indices

Background and objective We aimed to determine the diameters and respiratory variability of the subclavian vein (SCV), internal jugular vein (IJV), and femoral vein (FV), which are more superficial and easier to visualize with point-of-care ultrasound (PoCUS) in the detection of volume overload, and to investigate whether they can be an alternative to analyzing an inferior vena cava (IVC) to determine volume load. Methodology We prospectively evaluated volume-overloaded and normovolemic patients admitted to the emergency department using PoCUS for six months. Inspiratory-expiratory diameters and collapsibility indices (CI) of IVC and SCV, IJV, and FV were evaluated. The correlation between IVC and SCV, IJV, and FV was analyzed. Results A total of 176 patients were included in the study, including 88 volume-overloaded patients in the study group and 88 normovolemic patients in the control group. The median values of the maximum and minimum diameters of the IVC, SCV, IJV, and FV in the study group were statistically higher compared to the control group. A moderate correlation was found between IVC and SCV, IVC and IJV, and IVC and FV for maximum diameters in all patients (p = 0.447, p = 0.515, and p = 450, respectively). There was a very weak correlation between the IVC-CI and the FV-CI in all patients (p = 0.160), and no correlation was found with the other veins. Conclusion The IVC-CI was not correlated with the SCV-CI, the IJV-CI, or the FV-CI in volume-overloaded patients; therefore, superficial venous vessels cannot be an alternative to the IVC.

Association of estimated plasma volume with new onset acute kidney injury in hospitalized COVID-19 patients

PURPOSE

To explore the association of estimated plasma volume (ePV) and plasma volume status (PVS) as surrogates of volume status with new-onset AKI and in-hospital mortality among hospitalized COVID-19 patients.

MATERIALS AND METHODS

We performed a retrospective multi-center study on COVID-19-related ARDS patients who were admitted to the Mayo Clinic Enterprise health system. Plasma volume was calculated using the formulae for ePV and PVS, and longitudinal analysis was performed to find the association of ePV and PVS with new-onset AKI during hospitalization as the primary outcome and in-hospital mortality as a secondary outcome.

RESULTS

Our analysis included 7616 COVID-19 patients with new-onset AKI occurring in 1365 (17.9%) and a mortality rate of 25.96% among them. A longitudinal multilevel multivariate analysis showed both ePV (OR 1.162; 95% CI 1.048-1.288, p=0.004) and PVS (OR 1.032; 95% CI 1.012-1.050, p=0.001) were independent predictors of new onset AKI. Higher PVS was independently associated with increased in-hospital mortality (OR 1.038, 95% CI 1.007-1.070, p=0.017), but not ePV (OR 0.868, 95% CI 0.740-1.018, p=0.082).

CONCLUSION

A higher PVS correlated with a higher incidence of new-onset AKI and worse outcomes in our cohort of hospitalized COVID-19 patients. Further large-scale and prospective studies are needed to understand its utility.

The role of point-of-care ultrasound to monitor response of fluid replacement therapy in pregnancy

Fluid management in obstetrical care is crucial because of the complex physiological conditions of pregnancy, which complicate clinical manifestations and fluid balance management. This expert review examined the use of point-of-care ultrasound to evaluate and monitor the response to fluid therapy in pregnant patients. Pregnancy induces substantial physiological changes, including increased cardiac output and glomerular filtration rate, decreased systemic vascular resistance, and decreased plasma oncotic pressure. Conditions, such as preeclampsia, further complicate fluid management because of decreased intravascular volume and increased capillary permeability. Traditional methods for assessing fluid volume status, such as physical examination and invasive monitoring, are often unreliable or inappropriate. Point-of-care ultrasound provides a noninvasive, rapid, and reliable means to assess fluid responsiveness, which is essential for managing fluid therapy in pregnant patients. This review details the various point-of-care ultrasound modalities used to measure dynamic changes in fluid status, focusing on the evaluation of the inferior vena cava, lung ultrasound, and left ventricular outflow tract. Inferior vena cava ultrasound in spontaneously breathing patients determines diameter variability, predicts fluid responsiveness, and is feasible even late in pregnancy. Lung ultrasound is crucial for detecting early signs of pulmonary edema before clinical symptoms arise and is more accurate than traditional radiography. The left ventricular outflow tract velocity time integral assesses stroke volume response to fluid challenges, providing a quantifiable measure of cardiac function, which is particularly beneficial in critical care settings where rapid and accurate fluid management is essential. This expert review synthesizes current evidence and practice guidelines, suggesting the integration of point-of-care ultrasound as a fundamental aspect of fluid management in obstetrics. It calls for ongoing research to enhance techniques and validate their use in broader clinical settings, aiming to improve outcomes for pregnant patients and their babies by preventing complications associated with both under- and overresuscitation.

Review: sepsis guidelines and core measure bundles

Sepsis is a major cause of mortality worldwide and is the third-leading cause of death in the United States. Sepsis is resource-intensive and requires prompt recognition and treatment to reduce mortality. The impact of sepsis is not only on in-hospital survival but extends into post-discharge quality of life and risk of re-admission. As the understanding of sepsis physiology evolved, so have the recommended screening tools and treatment protocol which challenge prior standards of care. There have been noteworthy efforts by the Surviving Sepsis Campaign, the Third International Consensus Definitions for Sepsis and the Centers for Medicare and Medicaid Services to establish core measure bundles. This review highlights both the 2021 SSC International Guidelines and the 2015 CMS Severe Sepsis/Septic Shock Core Measure Bundle, or SEP-1. Notably, the SEP-1 bundle was implemented as a value-based purchasing program, linking care of sepsis patients to financial incentives. The objective is to explore the most current evidence-based data to inform clinical practice while utilizing the available guidelines as a roadmap.

Point-of-Care Ultrasound in Critical Care Obstetrics: A Scoping Review of the Current Evidence

OBJECTIVES

To synthesize the current evidence of maternal point-of-care ultrasound (POCUS) in obstetrics. A scoping review was conducted using PubMed, Clinicaltrials.gov, and the Cochrane library from inception through October 2023.

METHODS

Studies were eligible for inclusion if they described the use of POCUS among obstetric or postpartum patients. Two authors independently screened all abstracts. Quantitative, qualitative, and mixed-methods studies were eligible for inclusion. Case reports of single cases, review articles, and expert opinion articles were excluded. Studies describing detailed maternal nonobstetric sonograms or maternal first trimester sonograms to confirm viability and rule out ectopic pregnancy were also excluded. Data were tabulated using Microsoft Excel and summarized using a narrative review and descriptive statistics.

RESULTS

A total of 689 publications were identified through the search strategy and 12 studies met the inclusion criteria. Nine studies evaluated the use of lung POCUS in obstetrics in different clinical scenarios. Lung ultrasound (LUS) findings in preeclampsia showed an excellent ability to detect pulmonary edema (area under the receiver operating characteristic 0.961) and findings were correlated with clinical evidence of respiratory distress (21 of 57 [37%] versus 14 of 109 [13%]; P = .001). Three studies evaluated abdominal POCUS, two of the inferior vena cava (IVC) to predict postspinal anesthesia hypotension (PSAH) and fluid receptivity and one to assess the rate of ascites in patients with preeclampsia. Patients with PSAH had higher IVC collapsibility (area under the curve = 0.950, P < .001) and, in patients with severe preeclampsia, there is a high rate of ascites (52%) associated with increased risk of adverse outcomes. There were no studies on the use of subjective cardiac POCUS.

CONCLUSION

POCUS use in the management of high-risk obstetrics has increased. LUS has been the most studied modality and appears to have a potential role in the setting of preeclampsia complicated by pulmonary edema. Cardiac and abdominal POCUS have not been well studied. Trials are needed to evaluate its clinical applicability, reliability, and technique standardization before widespread use.

Tactics of infusion therapy in patients with acute destructive pancreatitis: a narrative review

INTRODUCTION: Infusion therapy is the main method of correcting pathological changes that occur during the phase of “aseptic” inflammation in acute pancreatitis. OBJECTIVE: Summarize current data on infusion therapy regimens in patients with acute destructive pancreatitis, the advisability of using various infusion solutions and options for monitoring the effectiveness of therapy. MATERIALS AND METHODS: The study was carried out in accordance with international reporting requirements for reviews (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The search was carried out in the following Internet search engines Pubmed and Cochrane Controlled Clinical Trials Register. To select articles, a literature reference search method was also used. The search strategy did not include restrictions on language, article type, or date. RESULTS: The analysis of literature data revealed two approaches to infusion therapy. The initial interest in “aggressive (4 liters per day or more)” infusion therapy regimens in the first 24 hours of the disease has now been replaced by a trend towards less “aggressive” regimens due to the publication of works on the high incidence of various complications (progression of organ dysfunction, local complications). When considering the qualitative composition of infusion therapy, preference should certainly be given to crystalloids. Basic monitoring of infusion therapy should include non-invasive methods: heart rate, blood pressure, diuresis rate. CONCLUSIONS: The analysis demonstrated different approaches to the tactics of infusion therapy in this category of patients. further research into the effectiveness and safety of infusion therapy, taking into account the varying severity of acute pancreatitis, the possibility of the influence of the qualitative composition of the infusion on the course of this disease and the formation of recommendations for initial and maintenance infusion therapy based on the principles of personalized medicine.

The diagnostic accuracy of preoperative perfusion index as a predictor of postspinal anesthesia hypotension in parturients undergoing cesarean delivery: A prospective non-blinded observational study

BACKGROUND AND OBJECTIVES

Spinal anesthesia is the technique of choice for elective cesarean section with a prominent side effect of postspinal anesthesia hypotension (PSH). This needs an early prediction to avoid feto-maternal complication. This study aimed to assess the diagnostic accuracy of perfusion index (PI) and inferior vena cava collapsibility index (IVCCI) in the prediction of PSH.

MATERIAL AND METHODS

Thirty parturients of American Society of Anesthesiologists Physical Status (ASA-PS) 1 and two undergoing cesarean delivery participated in the study. IVCCI, PI, baseline systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), and heart rate (HR) were noted in the preoperative period. The fall of MBP by 20% from baseline or below 65 mm Hg was considered PSH. After spinal anesthesia, SBP, DBP, MBP, and HR were noted again for diagnosing PSH.

RESULTS

It did not show any statistical difference when comparing the PI between the PSH and non-PSH groups in both the PSH definition groups. IVCCI was significantly higher when PSH was considered MBP <65 mm Hg (P = 0.01). However, IVCCI was found to be statistically insignificant if PSH was considered a 20% reduction in baseline MBP. The correlation matrix between IVCCI and PI showed Pearson's r-value of 0.525, indicating a substantial relationship between the two (P = 0.003). Multivariate logistic regression analysis had shown that neither IVCCI nor PI was a good predictor of PSH in parturients for both definition groups for PSH.

CONCLUSION

Although there is a modest correlation between PI and IVCCI, both cannot be used to predict postspinal hypotension in parturients undergoing elective lower-segment cesarean section (LSCS).

Association of plasma volume status with outcomes in hospitalized Covid-19 ARDS patients: A retrospective multicenter observational study

PURPOSE

To evaluate the association of estimated plasma volume (ePV) and plasma volume status (PVS) on admission with the outcomes in COVID-19-related acute respiratory distress syndrome (ARDS) patients.

MATERIALS AND METHODS

We performed a retrospective multi-center study on COVID-19-related ARDS patients who were admitted to the Mayo Clinic Enterprise health system. Plasma volume was calculated using the formulae for ePV and PVS, and these variables were analyzed for correlation with patient outcomes.

RESULTS

Our analysis included 1298 patients with sequential organ failure assessment (SOFA) respiratory score ≥ 2 (PaO2/FIO2 ≤300 mmHg) and a mortality rate of 25.96%. A Cox proportional multivariate analysis showed PVS but not ePV as an independent correlation with 90-day mortality after adjusting for the covariates (HR: 1.015, 95% CI: 1.005-1.025, p = 0.002 and HR 1.054, 95% CI 0.958-1.159, p = 0.278 respectively).

CONCLUSION

A lower PVS on admission correlated with a greater chance of survival in COVID-19-related ARDS patients. The role of PVS in guiding fluid management should be investigated in future prospective studies.

Inferior vena cava ultrasound and other techniques for assessment of intravascular and extravascular volume: an update

Goals of volume management are to accurately assess intravascular and extravascular volume and predict response to volume administration, vasopressor support or volume removal. Data are reviewed that support the following: (i) Dynamic parameters reliably guide volume administration and may improve clinical outcomes compared with static parameters, but some are invasive or only validated with mechanical ventilation without spontaneous breathing. (ii) Ultrasound visualization of inferior vena cava (IVC) diameter variations with respiration reliably assesses intravascular volume and predicts volume responsiveness. (iii) Although physiology of IVC respiratory variations differs with mechanical ventilation and spontaneous breathing, the IVC collapsibility index (CI) and distensibility index are interconvertible. (iv) Prediction of volume responsiveness by IVC CI is comparable for mechanical ventilation and spontaneous breathing patients. (v) Respiratory variations of subclavian/proximal axillary and internal jugular veins by ultrasound are alternative sites, with comparable reliability. (vi) Data support clinical applicability of IVC CI to predict hypotension with anesthesia, guide ultrafiltration goals, predict dry weight, predict intra-dialytic hypotension and assess acute decompensated heart failure. (vii) IVC ultrasound may complement ultrasound of heart and lungs, and abdominal organs for venous congestion, for assessing and managing volume overload and deresuscitation, renal failure and shock. (viii) IVC ultrasound has limitations including inadequate visualization. Ultrasound data should always be interpreted in clinical context. Additional studies are required to further assess and validate the role of bedside ultrasonography in clinical care.

The Role of Ultrasonographic Inferior Vena Cava Measurement in the Volume-Based Classification of Patients With Hyponatremia

OBJECTIVES

To demonstrate the role of inferior vena cava (IVC) collapsibility in the assessment of volume status in hyponatremic critically ill patients in the emergency department (ED) with bedside IVC imaging and to predict volume status with response to fluid therapy.

METHODS

A prospective 110 hypotonic hyponatremic patients aged >18 years with a serum sodium level under 125 mEq/L and at least one symptom of hyponatremia, who presented or referred to the ED was conducted. Demographical, clinical, and laboratory characteristics with bedside measurement of IVC diameter of patients were recorded. Volume status was divided into 3 subgroups: hypovolemic-G1, euvolemic-G2, and hypervolemic-G3. An ED trainee with a certification to perform basic and advanced ultrasonography (USG) training carried out the USG examinations. A diagnostic algorithm approach was made according to the results.

RESULTS

Symptom severity was significantly greater in the hypervolemic group than the other groups (P = .009 and P = .034, respectively). Systolic blood pressure (SBP) and mean arterial pressure (MAP) were significantly lower in the hypovolemic group compared with the other groups (P < .001 and P = .003, respectively). There was a significant difference between the ultrasonographically measured IVC min, IVC max, and mean IVC values across the three volume-based groups (P < .001).

CONCLUSION

Considering the diversity of physical examination (PE) findings, with the highly heterogenous nature of hyponatremia, a new measurable algorithm can be developed on the basis of contemporary hyponatremic patient management guidelines.

Processing Ultrasound Scans of the Inferior Vena Cava: Techniques and Applications

The inferior vena cava (IVC) is the largest vein in the body. It returns deoxygenated blood to the heart from the tissues placed under the diaphragm. The size and dynamics of the IVC depend on the blood volume and right atrial pressure, which are important indicators of a patient's hydration and reflect possible pathological conditions. Ultrasound (US) assessment of the IVC is a promising technique for evaluating these conditions, because it is fast, non-invasive, inexpensive, and without side effects. However, the standard M-mode approach for measuring IVC diameter is prone to errors due to the vein movements during respiration. B-mode US produces two-dimensional images that better capture the IVC shape and size. In this review, we discuss the pros and cons of current IVC segmentation techniques for B-mode longitudinal and transverse views. We also explored several scenarios where automated IVC segmentation could improve medical diagnosis and prognosis.

Post-Cardiac Arrest Care

A structured approach to postcardiac arrest care is needed. Although immediate goals include obtaining a blood pressure reading and ECG immediately after return of spontaneous circulation, other more advanced goals include minimizing CNS injury, managing cardiovascular dysfunction, reducing systemic ischemic/reperfusion injury, and identifying and treating the underlying cause to the arrest. This article summarizes the current understanding of the hemodynamic, neurologic, and metabolic abnormalities encountered in postarrest patients.

Point of Care Ultrasound in Exotic Animal Emergency and Critical Care

Exotic pets are presented to veterinary clinics with increasing frequency for routine, urgent, and emergency needs. With these increased visits, owners' expectations for high-quality veterinary care are also increasing. Many presenting complaints of reptiles, birds, and small mammals can benefit from the use of point of care ultrasound (POCUS) to establish a minimum database, aid in triage, and help guide further diagnostics, treatment, and prognostic discussions with the owner. Hospitalized exotic patients can also have their progress tracked and better assessed with the aid of POCUS.

Intra-and inter-observer variability of point of care ultrasound measurements to evaluate hemodynamic parameters in healthy volunteers

BACKGROUND

Point-of-care ultrasound (POCUS) is a valuable tool for assessing the hemodynamic status of acute patients. Even though POCUS often uses a qualitative approach, quantitative measurements have potential advantages in evaluating hemodynamic status. Several quantitative ultrasound parameters can be used to assess the hemodynamic status and cardiac function. However, only limited data on the feasibility and reliability of the quantitative hemodynamic measurements in the point-of-care setting are available. This study investigated the intra- and inter-observer variability of PoCUS measurements of quantitative hemodynamic parameters in healthy volunteers.

METHODS

In this prospective observational study, three sonographers performed three repeated measurements of eight different hemodynamic parameters in healthy subjects. An expert panel of two experienced sonographers evaluated the images' quality. The repeatability (intra-observer variability) was determined by calculating the coefficient of variation (CV) between the separate measurements for each observer. The reproducibility (inter-observer variability) was assessed by determining the intra-class correlation coefficient (ICC).

RESULTS

32 subjects were included in this study, on whom, in total, 1502 images were obtained for analysis. All parameters were in a normal physiological range. Stroke volume (SV), cardiac output (CO), and inferior vena cava diameter (IVC-D) showed high repeatability (CV under 10%) and substantial reproducibility (ICC 0.61-0.80). The other parameters had only moderate repeatability and reproducibility.

CONCLUSIONS

We demonstrated good inter-observer reproducibility and good intra-observer repeatability for CO, SV and IVC-D taken in healthy subjects by emergency care physicians.

Norepinephrine May Exacerbate Septic Acute Kidney Injury: A Narrative Review

Sepsis, the most serious complication of infection, occurs when a cascade of potentially life-threatening inflammatory responses is triggered. Potentially life-threatening septic shock is a complication of sepsis that occurs when hemodynamic instability occurs. Septic shock may cause organ failure, most commonly involving the kidneys. The pathophysiology and hemodynamic mechanisms of acute kidney injury in the case of sepsis or septic shock remain to be elucidated, but previous studies have suggested multiple possible mechanisms or the interplay of multiple mechanisms. Norepinephrine is used as the first-line vasopressor in the management of septic shock. Studies have reported different hemodynamic effects of norepinephrine on renal circulation, with some suggesting that it could possibly exacerbate acute kidney injury caused by septic shock. This narrative review briefly covers the updates on sepsis and septic shock regarding definitions, statistics, diagnosis, and management, with an explanation of the putative pathophysiological mechanisms and hemodynamic changes, as well as updated evidence. Sepsis-associated acute kidney injury remains a major burden on the healthcare system. This review aims to improve the real-world clinical understanding of the possible adverse outcomes of norepinephrine use in sepsis-associated acute kidney injury.

Pre-anesthesia ultrasound monitoring of subclavian vein diameter changes induced by modified passive leg raising can predict the occurrence of hypotension after general anesthesia: a prospective observational study

BACKGROUND

Perioperative hypotension increases postoperative complication rates and prolongs postoperative recovery time. Whether Passive Leg Raising test (PLR) and Subclavian Vein Diameter (DSCV) can effectively predict post-anesthesia hypotension remains to be tested. This study aimed to identify specific predictors of General Anesthesia (GA)induced hypotension by measuring DSCV in the supine versus PLR position.

METHODS

A total of 110 patients who underwent elective gynecological laparoscopic surgery under general anesthesia, were enrolled in this study. Before anesthesia, DSCV and theCollapsibility Index of DSCV(DSCV-CI) were measured by ultrasound, and the difference in maximal values of DSCV between supine and PLR positions was calculated, expressed as ΔDSCV. Hypotension was defined as Mean Blood Pressure (MBP) below 60mmhg or more than 30% below the baseline. Patients were divided into two groups according to the presence (Group H) or absence (Group N) of postanesthesia hypotension. The area under the receiver operating characteristic curve (ROC) and logistic regression analyses were used to evaluate the predictability of DSCV and other parameters for predicting preincision hypotension.

RESULTS

Three patients were excluded due to unclear ultrasound scans, resulting in a total of 107 patients studied. Twenty-seven (25.2%) patients experienced hypotension. Area under the ROC curve of ΔDSCV was 0.75 (P < 0.001) with 95% confidence interval (0.63-0.87), while DSCV and DSCV-CI were less than 0.7. The odds ratio (OR)of ΔDSCV was 1.18 (P < 0.001, 95%CI 1.09-1.27) for predicting the development of hypotension. ΔDSCV is predictive of hypotension following induction of general anesthesia.

CONCLUSIONS

ΔDSCV has predictive value for hypotension after general anesthesia.

TRIAL REGISTRATION

The trial was registered in the Chinese Clinical Trial Registry on 04/10/2021.

Noninvasive cardiac output monitor to quantify hydration status in ischemic stroke patients: A feasibility study

BACKGROUND

Individuals who are dehydrated, volume contracted or both at the time of hospitalization for acute ischemic stroke have worse clinical outcomes than do individuals with optimal volume status. Currently, there is no gold standard method for measuring hydration status, except indirect markers of a volume contracted state (VCS) including elevated blood urea nitrogen (BUN)/creatinine ratio. We sought to test the feasibility and acceptability of a non-invasive cardiac output monitor (NICOM) for the measurement of hydration status in a group of hospitalized ischemic stroke patients, and explore the relationship with a common indirect laboratory-based measure of VCS.

METHODS

We performed a prospective observational feasibility study of hospitalized acute ischemic stroke patients. We collected hemodynamic parameters using the NICOM device before and after fluid auto-bolus via passive leg raise and BUN/creatinine ratio. Successful acquisition of relevant hemodynamic data was the primary objective of this study. We explored agreement between the NICOM results and BUN/creatinine ratio using Cohen's kappa statistic.

RESULTS

Thirty patients hospitalized with acute ischemic stroke were enrolled. We found that 29/30 patients tolerated assessment with NICOM. Hemodynamic data were collected in all 30 patients. Data capture took an average of 10 min(SD ± 112 s). Agreement between NICOM and BUN/creatinine ratio was 70%; (expected agreement 51%; kappa 0.38). Agreement was stronger in the cohort without history of diabetes (81% agreement, kappa 0.61).

CONCLUSIONS

NICOM assessment was feasible in hospitalized stroke patients. The identification of an objective, real-time measure of hydration status would be clinically useful, and could allow precise, goal-directed care.

Classification of clinically relevant intravascular volume status using point of care ultrasound and machine learning

Purpose

This is a foundational study in which multiorgan system point of care ultrasound (POCUS) and machine learning (ML) are used to mimic physician management decisions regarding the functional intravascular volume status (IVS) and need for diuretic therapy. We present this as an impactful use case of an application of ML in aided decision making for clinical practice. IVS represents complex physiologic interactions of the cardiac, renal, pulmonary, and other organ systems. In particular, we focus on vascular congestion and overload as an evolving concept in POCUS diagnosis and clinical relevance. It is critical for physicians to be able to evaluate IVS without disrupting workflow or exposing patients to unnecessary testing, radiation, or cost. This work utilized a small retrospective dataset as a feasibility test for ML binary classification of diuretic administration validated with clinical decision data. Future work will be directed toward artificial intelligence (AI) delivery at the bedside and assessment of the impact on patient-centered outcomes and physician workflow improvement.

Approach

We retrospectively reviewed and processed 1039 POCUS video clips, including cardiac, thoracic, and inferior vena cava (IVC) views. Multiorgan POCUS clips were correlated with clinical data extracted from the electronic health record and deidentified for algorithm training and validation. We implemented a two-stream three-dimensional (3D) deep learning approach that fuses heart and IVC data to perform binary classification of the need for diuretic use.

Results

Our proposed approach achieves high classification accuracy (84%) for the determination of diuretic use with 0.84 area under the receiver operating characteristic curve.

Conclusions

Our two-stream 3D deep neural network is able to classify POCUS video clips that match physicians' classification for or against diuretic use with high accuracy. This serves as a foundational step in the progress toward AI-aided diagnosis and AI implementation in the field of IVS evaluation by POCUS.

Assessment of prescribed vs. achieved fluid balance during continuous renal replacement therapy and mortality outcome

BACKGROUND

Fluid management during continuous renal replacement therapy (CRRT) requires accuracy in the prescription of desired patient fluid balance (FBGoal) and precision in the attainable patient fluid balance (FBAchieved). Herein, we examined the association of the gap between prescribed vs. achieved patient fluid balance during CRRT (%FBGap) with hospital mortality in critically ill patients.

METHODS

Cohort study of critically ill adults with acute kidney injury (AKI) requiring CRRT and a prescription of negative fluid balance (mean patient fluid balance goal of negative ≥0.5 liters per day). Fluid management parameters included: 1) NUF (net ultrafiltration rate); 2) FBGoal; 3) FBAchieved; and 4) FBGap (% gap of fluid balance achieved vs. goal), all adjusted by patient's weight (kg) and duration of CRRT (hours).

RESULTS

Data from 653 patients (median of 102.2 patient-hours of CRRT) were analyzed. Mean (SD) age was 56.7 (14.6) years and 61.9% were male. Hospital mortality rate was 64%. Despite FBGoal was similar in patients who died vs. survived, survivors achieved greater negative fluid balance during CRRT than non-survivors: median FBAchieved -0.25 [-0.52 to -0.05] vs. 0.06 [-0.26 to 0.62] ml/kg/h, p<0.001. Median NUF was lower in patients who died vs. survived: 1.06 [0.63-1.47] vs. 1.22 [0.82-1.69] ml/kg/h, p<0.001, and median %FBGap was higher in patients who died (112.8%, 61.5 to 165.7) vs. survived (64.2%, 30.5 to 91.8), p<0.001. In multivariable models, higher %FBGap was independently associated with increased risk of hospital mortality: aOR (95% CI) 1.01 (1.01-1.02), p<0.001. NUF was not associated with hospital mortality when adjusted by %FBGap and other clinical parameters: aOR 0.96 (0.72-1.28), p = 0.771.

CONCLUSIONS

Higher %FBGap was independently associated with an increased risk of hospital mortality in critically ill adults with AKI on CRRT in whom clinicians prescribed negative fluid balance via CRRT. %FBGap represents a novel quality indicator of CRRT delivery that could assist with operationalizing fluid management interventions during CRRT.

Hyponatremia in the emergency department

Hyponatremia, defined as a serum sodium <135 mmol/L, is frequently encountered in patients presenting to the emergency department. Symptoms are often unspecific and include a recent history of falls, weakness and vertigo. Common causes of hyponatremia include diuretics, heart failure as well as Syndrome of Inappropriate Antidiuresis (SIAD) and correct diagnosis can be challenging. Emergency treatment of hyponatremia should be guided by presence of symptoms and focus on distinguishing between acute and chronic hyponatremia.

[Hemodynamic Monitoring in the ICU: the More Invasive, the Better?]

Less invasive or even completely non-invasive haemodynamic monitoring technologies have evolved during the last decades. However, the invasive devices such as the pulmonary artery catheter and transpulmonary thermodilution technologies are still the clinical gold standard in terms of advanced haemodynamic monitoring, especially in the treatment of critically ill patients. The current data situation regarding the early use of continuous haemodynamic monitoring in this patient population, specifically flow-based variables such as stroke volume to prevent occult hypoperfusion, is overwhelming. However, the effective implementation of these technologies in daily clinical routine is remarkably low. Given the fact that perioperative morbidity and mortality are higher than anticipated, anaesthesiologists and intensivists are in charge to deal with this problem. The recent advances in minimally invasive and non-invasive haemodynamic monitoring technologies may facilitate a more widespread use in the operating theatre and in critical care patients. This review evaluates the significance of invasive, minimally- and non-invasive monitoring devices and their specific haemodynamic variables in this particular field of perioperative medicine.

Diagnostic Accuracy of Ultrasonographic Respiratory Variation in the Inferior Vena Cava, Subclavian Vein, Internal Jugular Vein, and Femoral Vein Diameter to Predict Fluid Responsiveness: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to investigate the ultrasonographic variation of the diameter of the inferior vena cava (IVC), internal jugular vein (IJV), subclavian vein (SCV), and femoral vein (FV) to predict fluid responsiveness in critically ill patients. Relevant articles were obtained by searching PubMed, EMBASE, and Cochrane databases (articles up to 21 October 2021). The number of true positives, false positives, false negatives, and true negatives for the index test to predict fluid responsiveness was collected. We used a hierarchical summary receiver operating characteristics model and bivariate model for meta-analysis. Finally, 30 studies comprising 1719 patients were included in this review. The ultrasonographic variation of the IVC showed a pooled sensitivity and specificity of 0.75 and 0.83, respectively. The area under the receiver operating characteristics curve was 0.86. In the subgroup analysis, there was no difference between patients on mechanical ventilation and those breathing spontaneously. In terms of the IJV, SCV, and FV, meta-analysis was not conducted due to the limited number of studies. The ultrasonographic measurement of the variation in diameter of the IVC has a favorable diagnostic accuracy for predicting fluid responsiveness in critically ill patients. However, there was insufficient evidence in terms of the IJV, SCV, and FV.

Accuracy of Clarius, Handheld Wireless Point-of-Care Ultrasound, in Evaluating Prostate Morphology and Volume Compared to Radical Prostatectomy Specimen Weight: Is There a Difference between Transabdominal vs Transrectal Approach?

Background: Prostate size estimation is a valuable clinical measure widely utilized in urology. This study evaluated the accuracy of preoperative transabdominal ultrasound (TAUS) compared to radical prostatectomy specimens and transrectal ultrasound (TRUS) in estimating prostate volume and identifying presence of median lobe, across different size groups, using the standard ellipsoid formula. The effect of median lobe on accuracy was also assessed. Materials and Methods: Ninety-eight men undergoing robot-assisted radical prostatectomy were enrolled in this study. Preoperative evaluation of prostate volume was done using measurements obtained from TAUS using the Clarius C3 handheld wireless point-of-care ultrasound (POCUS) and from TRUS Clarius EC7. Participants were grouped based on prostate size (<30, 30-60, and >60 g). Mean absolute percentage of error was used to evaluate accuracy. Mean percentage of error determined if there was an overestimation or underestimation. Correlation between each TAUS size group, true prostate weight and TRUS was assessed. Results: Irrespective of body mass index, TAUS accurately identified median lobe in all men. No statistically significant difference was found between specimen weight and TAUS prostate size for the >60 g group. Among this same group, a strong correlation was noted between specimen weight and TAUS prostate size (r = 0.911, p < 0.001). There was also a strong correlation between TAUS and TRUS measurements for this group (r = 0.950, p < 0.001). Presence of median lobe did not have an impact on measurement accuracy. Conclusions: Bedside handheld wireless POCUS provides rapid, inexpensive, noninvasive, and clinically accurate TAUS prostate assessments for larger prostates. Such features as identifying median lobes and measuring prostate volumes are valuable tools, whereas patient counseling on lower urinary tract symptoms, elevated prostate-specific antigen, and benign prostate hyperplasia are surgical options.

Point-of-Care Ultrasound in Acute Care Nephrology

The use of point-of-care ultrasound (POCUS) is rapidly increasing in nephrology. It provides the opportunity to obtain complementary information that is more accurate than the classic physical examination. One can quickly follow the physical examination with a systematic POCUS evaluation of the kidneys, ureter bladder, inferior vena cava, heart, and lungs, which can provide diagnostic information and an accurate assessment of the patient's hemodynamics and volume status. Moreover, because it is safe and relatively easy to perform, it can be performed in a repeated manner as often as necessary so that the physician can reassess the patient's hemodynamics and volume status and adjust their therapy accordingly, permitting a more personalized approach to patient care (rather than blindly following protocols), especially to patients in acute care nephrology. Despite these advantages, nephrologists have been slow to adopt this diagnostic modality, perhaps because of lack of expertise. This review will provide an overview of the most commonly used POCUS examinations performed by nephrologists in the acute care setting. Its aim is to spark interest in in POCUS and to lay the foundation for readers to pursue more advanced training so that POCUS becomes a readily available tool in your diagnostic arsenal.

Effectiveness of an educational program on improving healthcare providers' knowledge of acute stroke: A randomized block design study

BACKGROUND

Stroke is a time-sensitive neurological disease and a life-threatening medical condition. Providing timely management for stroke patients is a crucial issue in healthcare settings. The primary objective of this study is to evaluate the effectiveness of an evidence-based educational program on healthcare providers' (HCPs) overall knowledge of stroke.

METHODS

A randomized block design with post-test only was used. A total of 189 HCPs (physicians, registered nurses, and paramedics) involved with treating stroke patients in the emergency were recruited. Participants were randomly assigned to either the intervention or waiting list control group. A one-session, stroke educational program was offered to the HCPs followed by a post-test designed to assess knowledge about stroke.

RESULTS

A significant main effect on the profession type was found, with physicians having higher mean scores of stroke knowledge compared with nurses and paramedics (F [2, 183]=48.55, P<0.001). The implemented educational program had a positive effect on increasing the level of stroke knowledge among HCPs (F [1, 183]=43.31, P<0.001). The utilization of any evidence-based assessment tools for patients with suspected stroke was denied by 36% of the total sample.

CONCLUSIONS

The implemented intervention can increase HCP's knowledge regarding stroke. Stroke education should be considered as one of the essential requirements for professional development for all HCPs in the emergency.

Restricting Daily Chest Radiography in the Intensive Care Unit: Implementing Evidence-Based Medicine to Decrease Utilizationt

Purpose

In this study, the authors applied evidence-based medicine to decrease the utilization of routine chest radiography in adult intensive care units and used time-driven activity-based costing to demonstrate cost savings.

Methods

A multidisciplinary team was formed with representatives from radiology, surgery, internal medicine, and nursing. The process of performing a portable chest radiographic examination was mapped, and time trials were performed by the radiology technologists and radiology resident. This information was used to determine the cost of performing portable intensive care unit (ICU) chest radiographic studies. The clinical team changed resident education, ordering protocols, and workflows to discontinue the use of routine daily chest radiography, emphasizing that it should be ordered only in specific situations, such as on admission or after central line placement. In addition, as a balancing measure, the team tracked complications such as unplanned extubations and ventilator days.

Results

Changing ordering practices in the adult ICUs to align with established evidence-based guidelines resulted in a 37% decrease in the utilization of portable chest radiography between June and December, without a concomitant increase in unplanned extubations or ventilator days. In addition, a proportionate cost savings was realized, as demonstrated by the application of time-driven activity-based costing.

Conclusions

This performance improvement initiative successfully increased the value of care delivered to ICU patients by aligning institutional clinical practice with evidence-based medicine. This resulted in decreased utilization and the cost associated with delivering care without a concomitant increase in complications.

Point-of-care ultrasound to evaluate volume status in severe hyponatremia

A 51-year-old man was hospitalised for severe hyponatremia. Initial history and physical examination suggested hypovolemia, and he was treated with normal saline at 100 mL/hour. After several days, his hyponatremia failed to improve, and then worsened without resolution of presenting ataxia and fatigue. He had no new complaints including no cough or orthopnea. He had no jugular venous distention or oedema, and his lungs were clear to auscultation. Point-of-care ultrasound was used, revealing a distended inferior vena cava, pulmonary oedema and pleural effusion, suggesting hypervolemia. Based on ultrasound findings, we treated with 60 mg oral torsemide two times per day. Hyponatremia resolved without complication within 48 hours. In this case, physical examination failed to recognise volume status change from hypovolemic to hypervolemic, increasing hospitalisation and morbidity. The point-of-care ultrasound proved to be an accurate tool for proper volume evaluation, and may be used as an adjunct to physical examination for hyponatremic patients.

Effect of neutrophil CD64 for diagnosing sepsis in emergency department

BACKGROUND

The aim of this study is to investigate the diagnostic and prognostic value of neutrophil CD64 (nCD64) as a novel biomarker in sepsis patients.

METHODS

One hundred fifty-one adult patients diagnosed with sepsis and 20 age-matched healthy controls were enrolled in the study. Patients with sepsis were further subdivided into a sepsis group and a septic shock group. nCD64 expression, serum procalcitonin (PCT) level, C-reactive protein (CRP) level, and white blood cell (WBC) count were obtained for each patient, and Sequential Organ Failure Assessment (SOFA) scores were calculated.

RESULTS

nCD64 expression was higher in the sepsis group with confirmed infection than in the control group. The receiver operating characteristic (ROC) curve of nCD64 was higher than those of SOFA score, PCT, CRP and WBC for diagnosing infection. The area under the curve (AUC) of nCD64 combined with SOFA score was the highest for all parameters. The AUC of nCD64 for predicting 28-day mortality in sepsis was significantly higher than those of PCT, CRP, and WBC, but slightly lower than that of SOFA score. The AUC of nCD64 or PCT combined with SOFA score was significantly higher than that of any single parameter for predicting 28-day mortality.

CONCLUSION

nCD64 expression and SOFA score are valuable parameters for early diagnosis of infection and prognostic evaluation of sepsis patients.

Retrospective analysis of eFAST ultrasounds performed on trauma activations at an academic level-1 trauma center

BACKGROUND

Point-of-care ultrasound (POCUS) has become increasingly integrated into the practice of emergency medicine. A common application is the extended focused assessment with sonography in trauma (eFAST) exam. The American College of Emergency Physicians has guidelines regarding the scope of ultrasound in the emergency department and the appropriate documentation. The objective of this study was to conduct a review of performed, documented and billed eFAST ultrasounds on trauma activation patients.

METHODS

This was a retrospective review of all trauma activation patients during a 10-month period at an academic level-one trauma center. A list comparing all trauma activations was cross-referenced with a list of all billed eFAST scans. Medical records were reviewed to determine whether an eFAST was indicated, performed, and appropriately documented.

RESULTS

We found that 1,507 of 1,597 trauma patients had indications for eFAST, but 396 (27%) of these patients did not have a billed eFAST. Of these 396 patients, 87 (22%) had documentation in the provider note that an eFAST was performed but there was no separate procedure note. The remaining 309 (78%) did not have any documentation of the eFAST in the patient's chart although an eFAST was recorded and reviewed during ultrasound quality assurance.

CONCLUSION

A significant proportion of trauma patients had eFAST exams performed but were not documented or billed. Lack of documentation was multifactorial. Emergency ultrasound programs require appropriate reimbursement to support training, credentialing, equipment, quality assurance, and device maintenance. Our study demonstrates a significant absence of adequate documentation leading to potential revenue loss for an emergency ultrasound program.