Inferior Vena Cava Ultrasonography Research Articles

Assessing Fluid Responsiveness Using Noninvasive Hemodynamic Monitoring in Pediatric Shock: A Review

AbstractNoninvasive hemodynamic monitoring devices have been introduced to better quantify fluid responsiveness in pediatric shock; however, current evidence for their use is inconsistent. This review aims to examine available noninvasive hemodynamic monitoring techniques for assessing fluid responsiveness in children with shock. A comprehensive literature search was conducted using PubMed and Google Scholar, examining published studies until December 31, 2022. Articles were identified using initial keywords: [noninvasive] AND [fluid responsiveness]. Inclusion criteria included age 0 to 18, use of noninvasive techniques, and the emergency department (ED) or pediatric intensive care unit (PICU) settings. Abstracts, review papers, articles investigating intraoperative monitoring, and non-English studies were excluded. The methodological index for nonrandomized studies (MINORS) score was used to assess impact of study bias and all study components were aligned with Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Our review yielded 1,353 articles, 17 of which met our inclusion criteria, consisting of 618 patients. All were prospective observational studies performed in the ED (n = 3) and PICU (n = 14). Etiologies of shock were disclosed in 13/17 papers and consisted of patients in septic shock (38%), cardiogenic shock (29%), and hypovolemic shock (23%). Noninvasive hemodynamic monitors included transthoracic echocardiography (TTE) (n = 10), ultrasonic cardiac output monitor (USCOM) (n = 1), inferior vena cava ultrasonography (n = 2), noninvasive cardiac output monitoring (NICOM)/electrical cardiometry (n = 5), and >2 modalities (n = 1). To evaluate fluid responsiveness, most commonly examined parameters included stroke volume variation (n = 6), cardiac index (CI) (n = 6), aortic blood flow peak velocity (∆V peak) (n = 3), and change in stroke volume index (n = 3). CI increase >10% predicted fluid responsiveness by TTE in all ages; however, when using NICOM, this increase was only predictive in children >5 years old. Additionally, ∆SV of 10 to 13% using TTE and USCOM was deemed predictive, while no studies concluded distensibility index by transabdominal ultrasound to be significantly predictive. Few articles explore implications of noninvasive hemodynamic monitors in evaluating fluid responsiveness in pediatric shock, especially in the ED setting. Consensus about their utility remains unclear, reiterating the need for further investigations of efficacy, accuracy, and applicability of these techniques.

Correlation of Internal Jugular Vein Collapsibility With Central Venous Pressure in Patients With Liver Cirrhosis.

We aimed to compare internal jugular vein and inferior vena cava ultrasonography as predictors of central venous pressure in cirrhotic patients. We performed ultrasound assessments of the internal jugular vein (IJV) and the inferior vena cava and then invasively measured central venous pressure (CVP). We then compared their correlation with CVP and performed area under the receiver operating characteristic curves to determine which had best sensitivity and specificity. IJV cross-sectional area collapsibility index at 30° correlated better with CVP ( r = -0.56, P < 0.001), and an IJV AP-CI at 30° ≤ 24.8% was better at predicting a CVP ≥8 mm Hg, with 100% sensitivity and 97.1% specificity. Thus, IJV point-of-care ultrasound might be superior than inferior vena cava point-of-care ultrasound as a predictor of CVP in cirrhotic patients.

Imaging diagnosis of intravenous leiomyomatosis: an institutional experience

To review and summarise the clinical and imaging characteristics of intravenous leiomyomatosis (IVL), a rare smooth muscle tumour originating from the uterus. Twenty-seven patients with a histopathological diagnosis of IVL who underwent surgery were reviewed retrospectively. All patients underwent pelvic ultrasonography, inferior vena cava (IVC) ultrasonography, and echocardiography before surgery. Computed tomography (CT) with contrast enhancement was performed in patients with extrapelvic IVL. Some patients underwent pelvic magnetic resonance imaging (MRI). Mean age was 44.81 years. Clinical symptoms were non-specific. IVL was intrapelvic in seven patients and extrapelvic in 20. Preoperative pelvic ultrasonography missed the diagnosis in 85.7% of patients with intrapelvic IVL. Pelvic MRI was useful to evaluate the parauterine vessels. Incidence of cardiac involvement was 59.26%. Echocardiography showed a highly mobile sessile mass in the right atrium with moderate-to-low echogenicity that originates from the IVC. Ninety per cent of extrapelvic lesions showed unilateral growth. The most common growth pattern was via the right uterine vein-internal iliac vein-IVC pathway. The clinical symptoms of IVL are non-specific. For patients with intrapelvic IVL, early diagnosis is difficult. Pelvic ultrasound should focus on the parauterine vessels, the iliac and ovarian veins should be explored carefully. MRI has obvious advantages in evaluating parauterine vessel involvement, which is helpful for early diagnosis. For patients with extrapelvic IVL, CT should be performed before surgery as part of a comprehensive evaluation. IVC ultrasonography and echocardiography are recommended when IVL is highly suspected.

Integrated lung and inferior vena cava ultrasonography for dry weight assessment in pediatric patients on regular hemodialysis: A single center study

Integrated lung and inferior vena cava ultrasonography for dry weight assessment in pediatric patients on regular hemodialysis: A single center study

The use ofpreoperative inferior vena cava ultrasound to predict anaesthesia-induced hypotension: asystematic review.

Preoperative ultrasound assessment of inferior vena cava (IVC) diameter and the collapsi-bility index might identify patients with intravascular volume depletion. The purpose of this review was to gather the existing evidence to find out whether preoperative IVC ultrasound (IVCUS) derived parameters can reliably predict hypotension after spinal or general anaesthesia. PubMed was searched to identify research articles that addressed the role of IVC ultrasound in predicting hypotension after spinal and general anaesthesia in adult patients. We included 4 randomized control trials and 17 observational studies in our final review. Among these, 15 studies involved spinal anaesthesia and 6 studies involved general anaesthesia. Heterogeneity with respect to the patient populations under evaluation, definitions used for hypotension after anaesthesia, IVCUS assessment methods, and cut-off values for IVCUS-derived parameters to predict hypotension precluded pooled meta-analysis. The maximum and minimum reported sensitivity of the IVC collapsibility index (IVCCI) for predicting post-spinal hypotension was 84.6% and 58.8% respectively, while the maximum and minimum specificities were 93.1% and 23.5% respectively. For the prediction of hypotension after general anaesthesia induction, the reported ranges of sensitivity and specificity of IVCCI were 86.67% to 45.5% and 94.29% to 77.27%, respectively. Current literature on the predictive role of IVCUS for hypotension after anaesthesia is heterogeneous both in methodology and in results. Standardization of the definition of hypotension under anaesthesia, method of IVCUS assessment, and the cut-offs for IVC diameter and the collapsibility index for prediction of hypotension after anaesthesia are necessary for drawing clinically relevant conclusions.

Non-invasive assessment of volume status of children with edema due to steroid sensitive nephrotic syndrome using urinary indices and inferior venacava ultrasonography

Background: It is clinically difficult to assess the intravascular volume status of children with edema in nephrotic syndrome. This makes decision-making challenging, regarding the use of diuretics or albumin infusion in the management of edema. Ideally, hormonal assay and central venous pressure monitoring are accurate but difficult to do as these methods are invasive and expensive to be applied to every child presenting with edema of nephrotic syndrome. Hence, the need for reliable non-invasive investigations to assess the volume status of children with edema. Aims and Objectives: The aim of the study was to assess the volume status of children with edema due to steroid sensitive nephrotic syndrome using noninvasive methods such as urinary indices (Fractional excretion of sodium (FeNa) and urine Potasium index (K index)) and inferior venacava diameter (IVCD) by ultrasonography and to determine the association between them. Materials and Methods: In this analytical cross-sectional study, 82 subjects fitting the inclusion criteria were included in the study. FeNa, K index and IVCD were determined. The volume status was assessed and association between the three calculated (Fischer exact test). Results: Out of 82 children, 56.1%, 68.3%, and 63.5% based on FeNa, K index, and IVCD respectively were having hypervolemic volume status. There is a statistically significant association between FeNa and K index and between urinary indices and IVCD. Conclusion: The present study supports the overfill hypothesis of edema formation. IVCD like urinary indices is a non-invasive and reliable investigation to determine volume status in nephrotic child with edema.

The Value of Inferior Vena Cava Ultrasonography Administration for Hypovolemia Detection in Patients with Acute Kidney Injury Hospitalized in Intensive Care Unit.

The hypo-perfusion of the kidneys can lead to impairment in renal function and induce renal injury in case of delayed diagnosis and treatment. To date, laboratory markers are routinely used to determine the fluid volume status of the patients. The current study aims to evaluate the values of inferior vena cava (IVC) collapsibility index in hypovolemia diagnosis among critical patients admitted at the intensive care unit (ICU). This is a cross-sectional study performed on 67 patients admitted to the ICU due to acute kidney injury from May 2018 to October 2019. Hypovolemia was assessed assessing IVC collapsibility using ultrasonography. Laboratory data, including urine osmolality, urine-plasma creatinine ratio, sodium excretion fraction and urinary sodium level were checked. Afterward, IVC collapsibility index was measured for each patient using ultrasonography and the values of this index in accordance with the mentioned criteria was evaluated. Accordingly, reciever operating curve was depicted. There was no significant asosociation between IVC collapsibility index with fractional excretion of sodium (P = 0.69), urine Na (P = 0.93) and urine osmolality ([P = 0.09]), while urine: Plasma creatinie ration revealed a significant association with IVC collapsibility index at cut point of 40.5% with sensitivity and specificity of 96% and 44% (P = 0.017, area under the curve: 0.67, 95% confidence interval: 0.551-0.804), respectively. According to the findings of this study, IVC collapsibility detected via ultrasonography was not an appropriate index to figure out hypovolemia in ICU patients. Furthermore, detailed studies are recommended.

The Value of Noninvasive Continuous Cardiac Output Monitoring in Assessment of Hemodynamic Status in Critically Ill Children

Access to reliable, rapid, and continuous hemodynamic monitoring parameters is essential for early diagnosis and prompt treatment of hemodynamic disorders in critically ill children. The aim of this observational study was to compare the accuracy of continuous non-invasive cardiac output monitoring (NICCOMO) device data with transthoracic echocardiography (TTE) and inferior vena cava (IVC) ultrasound findings in assessing cardiac output (C.I), circulatory fluid adequacy, and finally Determination of hemodynamic status in patients with Critical conditions hospitalized in the Pediatric Intensive Care Unit (PICU). In this observational study, forty-four critically ill children that were admitted to PICU were evaluated. We used NICCOMO, TTE, and IVC ultrasonography at the same time in critical patients. The association between NICCOMO parameters and echocardiogram cardiac index and IVC quality in ultrasound is compared. The agreement between CI measured by TTE and NICCOMO was assessed using the Bland-Altman analysis method. NICCOMO is not a reliable instrument for determining CI in children with an unstable hemodynamic status. However, the parameters of this device are reliable in assessing the patient's hemodynamic status. Findings showed that 90% of patients in the normal hemodynamic state in NICCOMO have SVR. I in the normal range (P&lt;0.001), and all cases in hypervolemic state had volume overload IVC in ultrasonography analysis. Noninvasive continuous cardiac output monitoring could be used to estimate unstable patients’ hemodynamic status in the initial stages for making timely treatment-related decisions, but its use for accurate cardiac index measurement is not reliable in all cases.

Correlation of preoperative inferior vena cava diameter and inferior vena cava collapsibility index with preoperative fasting status, patient demography and general anaesthesia associated hypotension: A prospective, observational study.

A definitive cutoff of inferior venacava (IVC) diameter in expiration (dIVCmax) and inferior vena cava collapsibility index (IVCCI) for predicting general anaesthesia associated hypotension (GAAH) is not yet determined. Primary objective of this study was to determine the correlation of dIVCmax and IVCCI, with GAAH. Other objectives were to determine the correlation of these IVC parameters with preoperative fasting duration, temperature and humidity. The correlation of dIVCmax with patient demography was also studied. A total of 110 adult patients undergoing elective surgery under general anaesthesia were included in the study. IVC ultrasonography was done in the preoperative room, 20 to 30 minutes before shifting the patient to the operating room. Hypotension at (hypo@) 2 minutes and 10 minutes after administering vecuronium was recorded. Hundred and seven patients were analysed. A significant positive correlation was present between patient height and dIVCmax (r = 0.25, P = 0.009). Area under receiver operating characteristics curve was 0.595 (95% confidence interval (CI) 0.485-0.705) and 0.568 (95% CI 0.458-0.679) for dIVCmax and IVCCI for predicting hypo@2 min, with a diagnostic accuracy of 54% and 53%, respectively. dIVCmax ≤1.14 cm had a sensitivity of 31% and specificity of 87% in predicting GAAH. IVCCI ≥63.3% could predict GAAH with 31% sensitivity and 84% specificity. No significant correlation was found between preoperative IVC parameters and preoperative fasting or environmental factors. Both dIVCmax and IVCCI have poor diagnostic accuracy, with good specificity and low sensitivity in predicting GAAH. A steady formula for calculating baseline IVC diameter adjusted for patient demography is needed.

Inferior vena cava ultrasonography before general anesthesia cannot predict arterial hypotension in patients undergoing vascular surgery.

Intraoperative hypotension (IH) is an independent predictor of mortality. Some experts have suggested that ultrasound measurement of the inferior vena cava (IVC) in spontaneous ventilation can predict IH. To evaluate the capacity of ultrasound measures of IVC in spontaneous ventilation to predict episodes of IH after anaesthesia induction. We studied 55 high-risk cardiac patients undergoing vascular surgery. The maximum (dIVCmax) and minimum (dIVCmin) diameter of the IVC were measured and the collapsibility index CI = (dIVCmax-dIVCmin)/dIVCmax was calculated prior to anaesthesia induction. Three definitions of IH were used: systolic blood pressure (SBP) less than 100 mmHg, mean arterial pressure (MAP) less than 60 mmHg, and a decrease in MAP greater than or equal to 30% compared to baseline. There were no significant differences in dIVCmax or in CI between patients presenting IH after anaesthesia induction and those who did not. ROC curves for dIVCmax showed an area under the curve of 0.55 (0.39-0.70), 0.69 (0.48-0.90), and 0.57 (0.42-0.73) and ROC curves for the CI were 0.62 (0.47-0.78), 0.60 (0.41-0.78) and 0.62 (0.47-0.78) for the 3 definitions of IH (<100 mmHg, MAP < 60 mmHg, and MAP ≥30% baseline), respectively. Ultrasound measurements of IVC in spontaneous ventilation are not good predictors of IH after anaesthesia induction in these patients. The optimal cut-off points show low specificity and moderate sensitivity for predicting IH.

Inferior vena cava ultrasonography in the assessment of intravascular volume status and fluid responsiveness in the emergency department and intensive care unit: A critical analysis review

Rapid evaluation of intravascular volume status is vital; either excessive or limited fluid administration may result in adverse patient outcomes. In this narrative review, critical analysis of pertinent diagnostic accuracy studies is developed to delineate the role of inferior vena cava ultrasound measurements in the assessment of both intravascular volume status and fluid responsiveness in the emergency department and intensive care unit. In addition, limitations, and technical considerations of inferior vena cava ultrasound measurements as well as directions for future research are thoroughly discussed.

Inferior Vena Cava Edge Tracking Echocardiography: A Promising Tool with Applications in Multiple Clinical Settings.

Ultrasound (US)-based measurements of the inferior vena cava (IVC) diameter are widely used to estimate right atrial pressure (RAP) in a variety of clinical settings. However, the correlation with invasively measured RAP along with the reproducibility of US-based IVC measurements is modest at best. In the present manuscript, we discuss the limitations of the current technique to estimate RAP through IVC US assessment and present a new promising tool developed by our research group, the automated IVC edge-to-edge tracking system, which has the potential to improve RAP assessment by transforming the current categorical classification (low, normal, high RAP) in a continuous and precise RAP estimation technique. Finally, we critically evaluate all the clinical settings in which this new tool could improve current practice.

Ultrasonographic Inferior Vena Cava Measurement is More Sensitive Than Vital Sign Abnormalities for Identifying Moderate and Severe Hemorrhage.

Ultrasound inferior vena cava (IVC) diameter has been shown to decrease in response to hemorrhage. IVC diameter cut points to identify moderate and severe blood loss have not been established. This study sought to find ultrasound IVC diameter cut points to identify moderate and severe hemorrhage and assess the performance of these cut points vs. vital sign abnormalities. This is a secondary analysis of data from a study that described changes in vital signs and sonographic measurements of the IVC during a lower body negative pressure model of hemorrhage. Using receiver operator curve analyses, optimal cut points for identifying moderate and severe hemorrhage were identified. The ability of these cut points to identify hemorrhage in patients with no vital sign abnormalities was then assessed. In both long- and short-axis views, maximum and minimum IVC diameters (IVCmax and IVCmin) were significantly lower than baseline in severe blood loss. The optimal cut point for IVCmax in both axes was found to be ≤ 0.8 cm. This cut point is able to distinguish between no blood loss vs. moderate blood loss, and no blood loss vs. severe blood loss. The optimal cut point for IVCmin was variable between axes and blood loss severity. IVC diameter cut points obtained were able to identify hemorrhage in patients with no vital sign abnormalities. An ultrasound IVCmax of ≤ 0.8 cm may be useful in identifying moderate and severe hemorrhage before vital sign abnormalities are evident.

Can Inferior Vena Cava Diameter and Collapsibility Index Be a Predictor in Detecting Preoperative Intravascular Volume Change in Pediatric Patients?

Abstract Background: Inferior vena cava (IVC) ultrasound measurement is a reliable indicator used in the assessment of intravascular volume status. The aim of this study was to evaluate intravascular volume changes in pediatric patients by measuring the IVC diameter and collapsibility index (CI) in children whose oral feeding was restricted preoperatively. Material and Methods: From May 2018 to October 2018, a total of 55 pediatric patients who were scheduled for surgery were included in this prospective, observational, cohort study. Fasting and satiety IVC diameters and CIs of patients were determined by ultrasonographic evaluation twice: in the preoperative preliminary evaluation, when the patients were satiated, and before surgery, during a fasting period of 6–8 hours. Ultra-sonographic data were recorded and compared between fasting and satiety periods. Results: In the grey scale (B-mode), mean IVC diameter was significantly higher when the patients were satiated, compared to the measurements made just before surgery during the fasting period. In the M-mode, the mean IVC diameter was significantly higher only during the inspiratory phase when the patients were satiated, while during the expiratory phase it was detected to be statistically similar. Mean CI was significantly higher in the immediate preoperative period, compared to the assessment made when satiated. Conclusion: Preoperative ultrasound IVC diameter and CI measurement can be a practical and useful method for evaluating preoperative intravascular volume in children.

MO881LUNG ULTRASONOGRAPHY AND BIOIMPEDANCE IN ASSESSMENT OF VOLUME STATUS OF HEMODIALYSIS PATIENTS: A COMPARISON BETWEEN BOTH METHODS

Abstract Background and Aims Assessment of volume status is an important prognostic factor in hemodialysis (HD) patients. Several methods have been suggested to estimate it: bioimpedance analysis, brain natriuretic peptide levels (BNP) and lung and inferior vena cava (IVC) ultrasonography (US), which are emerging as a valuable technique in this field. Our aim was to evaluate effectiveness of lung US in assessment of volume status in chronic HD patients and compare it with the gold standard bioimpedance technique. Method Cross-sectional study of 58 prevalent HD patients. Several analytical data were analyzed, including BNP, albumin and sodium levels. Lung and IVC US were performed to assess the presence and distribution of B-lines and the diameter and respiratory collapsibility of IVC, respectively. Fresenius® body composition monitor (BCM) was the bioimpedance technique used. It defines hyperhydration as relative fluid overload (RFO) &amp;gt;15%. Both US and BCM were performed at the same day, immediately before the middle week HD session. Categorical variables are presented as frequencies and percentages, continuous variables as means and standard deviations, or medians and interquartile ranges (IQR) for variables with skewed distributions. Statistical analysis was performed using SPSS® version 25 for Windows. Results The average age was 75.3±1.6 years and 56.9% were male. The average time in HD was 36.6±4.1 months. Half of the patients (n=29) presented B-lines in lung US. The diameter of IVC was significantly higher in this group of patients, both inhaling (1.3±0.4 vs 0.9±0.4; p=0.001) and exhaling (2.0±0.4 vs 1.6±0.5; p&amp;lt;0.001). Similarly, most patients with B-lines at lung US presented collapsibility of IVC &amp;lt; 50% (n=25; 89.3%). Although not statistically significant, the RFO was higher in patients with presence of B-lines compared to those who did not present it (10.2±10.6% vs 5.4±6.9%; p=0.061). Considering the mean RFO value in patients with B-lines, we observed that its presence was significantly higher in patients with RFO &amp;gt; 10% compared to those with RFO &amp;lt; 10% (58.6% vs 31%; p=0.035). Besides, patients with RFO &amp;gt; 10% also presented higher BNP (9878±34646 pg/mL vs 3945±8634 pg/mL; p=0.009) and lower albumin levels (3.4±0.5 vs 3.7±0.4; p= 0.039) than other group. Conclusion Lung US seems to be a valuable tool to diagnose overhydration earlier than BCM, which currently defines hyperhydration as RFO &amp;gt;15%. In this study we verified that patients with lower levels of RFO (&amp;gt;10%) already presented signals of fluid overload, such as presence of B-lines at lung US, higher BNP and lower albumin levels. These findings support the benefit of lung US in guiding fluid removal and may change the practice in our HD unit to probe the ideal dry weight for chronic dialysis patients.

Prevention of Contrast-Induced Nephropathy by Inferior Vena Cava Ultrasonography-Guided Hydration in Chronic Heart Failure Patients

Introduction: Contrast-induced nephropathy (CIN) is a common complication resulting from the administration of contrast media. This study was designed to determine whether inferior vena cava (IVC) ultrasonography (IVCU)-guided hydration can reduce the risk of CIN in chronic heart failure patients undergoing coronary angiography or coronary angiography with percutaneous coronary intervention compared with standard hydration. Methods: This prospective clinical trial enrolled 207 chronic heart failure patients from February 2016 to November 2017, who were randomly assigned to either the IVCU-guided hydration group (n = 104) or the routine hydration group (n = 103). In the IVCU-guided group, the hydration infusion rate was set according to the IVC diameter determined by IVCU, while the control group received intravenous infusion of 0.9% saline at 0.5 mL/(kg·h). Serum Cr was measured before and 48–72 h after the procedure. All patients were followed up for 18 months. The incidence of nephropathy and major adverse cardiovascular or cerebrovascular events (MACCEs) was also compared between the 2 groups. Results: Statistically significant difference between the 2 groups regarding the occurrence of CIN was observed (12.5 vs. 29.1%, p = 0.004). The hydration volume of the IVCU-guided group was significantly higher than that of the routine group (p < 0.001). In addition, patients receiving IVCU-guided hydration had significantly lower risk of developing MACCEs than patients in the control group during the 18-month follow-up (14.4 vs. 27.2%, p = 0.027). Conclusion: Our findings support that IVCU-guided hydration is superior to standard hydration in prevention of CIN and may substantially reduce longtime composite major adverse events.

Abstract 14936: Prevention of Contrast-induced Nephropathy by Inferior Vena Cava Ultrasonography-guided Hydration in Chronic Heart Failure Patients

Introduction: Contrast-induced nephropathy (CIN) is a common complication resulting from the administration of contrast media. This study was designed to determine whether inferior vena cava ultrasonography (IVCU)-guided hydration can reduce the risk of CIN in chronic heart failure patients undergoing coronary angiography or coronary angiography with percutaneous coronary intervention (PCI) than standard hydration. Methods: This prospective clinical trial enrolled 207 chronic heart failure patients from February 2016 to November 2017, who were randomly assigned to either IVCU-guided hydration group (n = 104) or the routine hydration group (n = 103). In the IVCU-guided group, the hydration infusion rate was set according to inferior vena cava diameter (IVC-D) determined by IVCU; while the control group received intravenous infusion of 0.9% saline at 0.5 ml/((kg·h)). Serum creatinine (SCr) was measured before and 48-72 hours after procedure. All patients were followed up for 18 months. The incidence of nephropathy and major adverse cardiovascular or cerebrovascular events (MACCE) were also compared between two groups. Results: Statistically significant difference between two groups regarding the occurrence of CIN were observed (12.5% vs. 29.1%, p = 0.003); The hydration volume of the IVCU-guided group is significantly higher than routine group (p&lt;0.001). In addition, patients receiving IVCU-guided hydration had significantly lower risk of developing MACCE compared with patients in control group during 18 months follow-up (14.4% vs. 27.2%, p = 0.027). Conclusions: IVCU-guided hydration is superior to standard hydration in prevention of CIN and substantially reduce longtime composite major adverse events.

Development of a Deep Learning Network to Classify Inferior Vena Cava Collapse to Predict Fluid Responsiveness.

To create a deep learning algorithm capable of video classification, using a long short-term memory (LSTM) network, to analyze collapsibility of the inferior vena cava (IVC) to predict fluid responsiveness in critically ill patients. We used a data set of IVC ultrasound (US) videos to train the LSTM network. The data set was created from IVC US videos of spontaneously breathing critically ill patients undergoing intravenous fluid resuscitation as part of 2 prior prospective studies. We randomly selected 90% of the IVC videos to train the LSTM network and 10% of the videos to test the LSTM network's ability to predict fluid responsiveness. Fluid responsiveness was defined as a greater than 10% increase in the cardiac index after a 500-mL fluid bolus, as measured by bioreactance. We analyzed 211 videos from 175 critically ill patients: 191 to train the LSTM network and 20 to test it. Using standard data augmentation techniques, we increased our sample size from 191 to 3820 videos. Of the 175 patients, 91 (52%) were fluid responders. The LSTM network was able to predict fluid responsiveness moderately well, with an area under the receiver operating characteristic curve of 0.70 (95% confidence interval [CI], 0.43-1.00), a positive likelihood ratio of infinity, and a negative likelihood ratio of 0.3 (95% CI, 0.12-0.77). In comparison, point-of-care US experts using video review offline and manual diameter measurement via software caliper tools achieved an area under the receiver operating characteristic curve of 0.94 (95% CI, 0.83-0.99). We demonstrated that an LSTM network can be trained by using videos of IVC US to classify IVC collapse to predict fluid responsiveness. Our LSTM network performed moderately well given the small training cohort but worse than point-of-care US experts. Further training and testing of the LSTM network with a larger data sets is warranted.

Correlation of inferior vena cava diameter and collapsibility index with central venous pressure in shocked patients

Objective The aim was to determine the correlation of the caval index, inferior vena cava (IVC) diameter, and central venous pressure (CVP) in shocked patients in the emergency room. Background Assessment of intravascular volume is important in shocked patients. It can be measured through many techniques, among those include CVP, collapsibility index, and diameter of IVC. Patients and methods This was a prospective and cross-sectional study and included 100 patients treated at the Emergency Department of Menoufia University Hospital. They were selected according to certain inclusion and exclusion criteria with already inserted central venous catheter and were measured for CVP, and concomitantly the IVC diameter was measured with ultrasound using M-mode to measure the expiratory and inspiratory diameter and collapsibility index of the IVC, and then the patients were divided into three groups according to the CVP, with CVP less than 10, CVP 10–15 and CVP more than 15. Results Among the 100 patients enrolled, the median age was 56.01 ± 20.92 years. The correlation of the CVP measurement with the ultrasound IVC caval index was r= −0.911 (P < 0.001), with the expiratory IVC diameter was r = 0.703 (P < 0.001), and with the inspiratory IVC diameter was r = 0.875 (P < 0.001). The sensitivity and specificity of the caval index showed that the cutoff points were 50, 40, and 20 at CVP levels 10, 10–15, and 15 cm H2 O, respectively. Conclusion This study found that in shocked patients there is a good correlation between CVP and collapsibility index, as well as with inspiratory and expiratory diameter of IVC.

Role of Point-of-Care Lung and Inferior Vena Cava Ultrasound in Clinical Decisions for Patients Presenting to the Emergency Department With Symptoms of Acute Decompensated Heart Failure.

This prospective study was performed to evaluate the diagnostic role of point-of-care lung ultrasound (LUS) and inferior vena cava (IVC) ultrasound in patients with acute decompensated heart failure (ADHF). A prospective cohort study was conducted between January 2018 and November 2018 on patients with a diagnosis of ADHF in the emergency department (ED). On admission, LUS findings, inspiratory and expiratory IVC diameters, and the inferior vena cava collapsibility index (IVCCI) were obtained. After therapeutic interventions, third-hour changes in LUS and the IVC index and the treatment response were assessed. Eighty patients were enrolled. Forty-six (58%) patients had an ejection fraction (EF) greater than 40%, and 34 (42%) had an EF of less than 40%. Significant differences were detected between the admission and third-hour inspiratory IVC diameter, expiratory IVC diameter, and IVCCI (P = .001). There was no correlation between the EF and inspiratory IVC diameter (r = -0.03; P = .976), expiratory IVC diameter (r = -109; P = .336), or IVCCI (r = -0.72; P = .523) and between the B-type natriuretic peptide level and inspiratory IVC diameter (r = -0.58; P = .610), expiratory IVC diameter (r = -0.33; P = .774), or IVCCI (r = -0.78; P = .493) either. A comparison of admission and third-hour numbers of B-lines on LUS imaging showed a significant decrease in the number of B-lines in all zones at the end of 3 hours (P = .001). A significant difference existed between the hospitalized and discharged patients with respect to IVC diameters and number of B-lines. In the ED setting, an assessment of B-lines and measurement of IVC diameters are better markers than the B-type natriuretic peptide level, EF, or chest x-ray for diagnosis of ADHF and can be used to make decisions for hospitalization or discharge from the ED.