Maximum Inferior Vena Cava Diameter Research Articles

Lack of correlation between different congestion markers in acute decompensated heart failure

BackgroundHospitalizations for acute decompensated heart failure (ADHF) are commonly associated with congestion-related signs and symptoms. Objective and quantitative markers of congestion have been identified, but there is limited knowledge regarding the correlation between these markers.MethodsPatients hospitalized for ADHF irrespective of left ventricular ejection fraction were included in a prospective registry. Assessment of congestion markers (e.g., NT-proBNP, maximum inferior vena cava diameter, dyspnea using visual analogue scale, and a clinical congestion score) was performed systematically on admission and at discharge. Telephone interviews were performed to assess clinical events, i.e., all-cause death or readmission for cardiovascular cause, after discharge. Missing values were handled by multiple imputation.ResultsIn total, 130 patients were prospectively enrolled. Median length of hospitalization was 9 days (interquartile range 6 to 16). All congestion markers declined from admission to discharge (p < 0.001). No correlation between the congestion markers could be identified, neither on admission nor at discharge. The composite endpoint of all-cause death or readmission for cardiovascular cause occurred in 46.2% of patients. Only NT-proBNP at discharge was predictive for this outcome (hazard ratio 1.48, 95% confidence interval 1.15 to 1.90, p = 0.002).ConclusionNo correlation between quantitative congestion markers was observed. Only NT-proBNP at discharge was significantly associated with the composite endpoint of all-cause death or readmission for cardiovascular cause. Findings indicate that the studied congestion markers reflect different aspects of congestion.Graphical abstract

The Sonographic Measurement of the Inferior Vena Cava Diameter versus the Central Venous Pressure in Assessing Fluid Responsiveness in Patients after Coronary Artery Bypass Graft Surgery

Background: Fluid status assessment and management post coronary artery bypass grafting (CABG) is a clinical challenge. The study aimed to establish whether central venous pressure (CVP) and ultrasound measures of respiratory variability of inferior vena cava (IVC) diameter might predict fluid responsiveness in mechanically ventilated patients after CABG.&#x0D; Methods: This comparative study included 200 consecutive adult patients who underwent elective CABG. We recorded the following parameters: heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), central venous pressure (CVP), inferior vena cava maximum (IVCmax), and minimum (IVCmin) diameters, left ventricular ejection fraction (LVEF), and velocity-time integral in the left ventricular outflow tract (VTI-LVOT).&#x0D; Results: The age of the patients ranged from 45 to 71 years, and 147 were males (73.5%). Patients were grouped into fluid responders (n= 135), defined as stroke volume variation (SVV) of 15% or greater following fluid bolus administration, and fluid non-responders (n= 65), defined SVV of less than 15% following fluid bolus administration. There was no statistically significant difference between the groups regarding their CVP, maximum and minimum IVC diameters, inferior vena cava distensibility index (IVC-DI), and other markers of fluid responsiveness (p-value 0.47, 0.34, 0.59, and 0.64, respectively). There was a significant difference in SVV between fluid responders (18.33±2.767) and non-responders (10.95±1.940) (p-value &lt;0.001).&#x0D; Conclusion: Neither CVP nor sonographic measures of IVC diameter respiratory variability provided an accurate method to distinguish between fluid responders and non-responders in the early postoperative period after CABG.

IVC measurement for the noninvasive evaluation of central venous pressure.

Central venous pressure (CVP) is one of only a handful of variables that can be used to assess a patient's volume status to attempt to optimize stroke volume. The gold standard method for assessing CVP is though pulmonary artery catheterization, which is invasive and risks severe complications such as pneumothorax and cardiac conduction abnormalities. Current noninvasive methods for estimating CVP such as jugular venous pressure assessment are imperfect with wide inter-examiner variability. The inferior vena cava (IVC) is a highly compliant vessel that uniquely does not constrict in response to hypovolemia, making it an ideal, noninvasive surrogate for the estimation of CVP. A range of IVC indices including minimum and maximum IVC diameter and fraction of IVC collapse with inspiration (known as collapsibility index) have been studied with highly variable results that range from excellent to poor correlation between these values and CVP. Despite this inconsistency in findings, multiple schemes have been proposed to attempt to estimate CVP from IVC measurements, but when prospectively tested, none has been shown to be accurate. Since the most recent 2015 American Society of Echocardiography guidelines, multiple studies have identified unique ways of improving the accuracy of IVC measurement, which could translate into better CVP estimation. The goal of this review is to summarize the many, often conflicting studies that exist in this area, and provide recommendations for future studies based on our findings.

Can vena cava ultrasound-guided volume repletion prevent general induced hypotension in elderly patients? A mini-fluid challenge

BackgroundHypotension is often occurring after induction of general anesthesia (IGA) and can cause organ hypoperfusion and ischemia which associated with adverse outcomes in patients having both cardiac and non-cardiac surgery. Elderly patients are particularly more vulnerable and at increased risk to the depressant effect of anesthetic drugs. So, recognition and prevention of such event are of clinical importance. This study recruited patients aged above 60 years, with ASA physical status classification I-II-III who were scheduled for surgery under general anesthesia with the aim to assess the effectiveness of preoperative IVC ultrasonography in predicting hypotension which develops following IGA and its association with the volume status in elderly patients receiving general anesthesia, through measurements of the maximum inferior vena cava diameter (dIVCmax), minimum inferior vena cava diameter (dIVCmin), inferior vena cava collapsibility index (IVC-CI), and basal and post-induction mean arterial pressure (MAP).ResultsThirty-nine (44.3%) of the 88 patients developed hypotension after IGA, and it was significantly more in patients who did not receive preoperative fluid (p = 0.045). The cut-off for dIVCmax was found as 16.250 mm with the ROC analysis. Specificity and sensitivity for the cut-off value of 16.250 mm were calculated as 61.2% and 76.9%, respectively. The cut-off for IVC-CI was found as 33.600% with the ROC analysis. Specificity and sensitivity for the cut-off value of 33.600% were calculated as 68.7% and 87.2%, respectively.ConclusionsIVC ultrasonography may be helpful in the prediction of preoperative hypovolemia in elderly patients in the form of high IVC-CI and low dIVCmax. The incidence of hypotension was lower in patients who received fluid infusion before IGA.

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.

Correlation of Inferior Vena Cava diameter and IVC Collapsibility Index with Central Venous Pressure (CVP) in critically ill surgical patients

Introduction: Central Venous Pressure is a valuable parameter in the management of critically ill surgical patients in the ICU. Non-invasive methods to extrapolate the volume status of the patient can aid clinicians in expediting proper treatment. The objective of this study is to find a correlation between Inferior Vena cava (IVC) diameter and collapsibility index (CI) with Central venous pressure (CVP) in critically ill surgical patients. Methods: This cross-sectional study included 60 critically ill patients from September 2020 – 31st February 2021. We recorded the patient's age, sex, heart rate, blood pressure, CVP, volume status, IVC minimum, and maximum diameter. After taking consent and explaining the procedure to the patient, the maximum IVC anteroposterior diameter was noted at the end of inspiration and end of expiration in centimeters. IVC collapsibility index was calculated using the formula ([IVCdmax-IVCdmin]/IVCdmax*100%). Following this, the CVP of the patient was measured. Results: Among the patients evaluated, 32 were females. The mean age of the participants was 44.90 ± 15.76 years. The mean central venous pressure maintained was 11.10 ± 2.11cm H2O with an inferior vena cava collapsibility index of 29.69 ± 8.75. There was a negative correlation between CVP and IVC collapsibility index (%), which was statistically significant (r = -0.701, n = 60, p &lt; 0.01). A strong positive correlation between CVP and maximum IVC diameter (r = 0.712, n = 60, p &lt; 0.01) and minimum IVC diameter (r = 0.796, n = 60, p &lt; 0.01) was found. Conclusion: Inferior Vena Cava diameter and IVC Collapsibility Index can be used as a reliable substitute to central venous pressure to determine the patient's volume status.

Factors influencing inferior vena cava diameter and its respiratory variation: Simultaneous comparison with hemodynamic data

BackgroundUltrasound assessment of inferior vena cava (IVC) diameter and its respiratory variation is widely used to estimate right atrial pressure (RAP). Generally, the IVC distends as the RAP rises; however, there may be discrepancies between the values. Therefore, it is critical to recognize clinical factors other than RAP that may influence IVC measurements. MethodsWe obtained the IVC maximum diameter and IVC collapsibility index (IVCCI) simultaneously during right-heart catheterization in 71 consecutive patients. Then, we assessed various clinical and hemodynamic factors to elucidate the independent determinants of IVC measurements. Moreover, we tried to generate the regression equation to estimate mean RAP from the IVC maximum diameter and IVCCI. ResultsThe mean IVC maximum diameter and IVCCI were 15 ± 4 mm and 51 ± 15%, respectively. In stepwise multivariate analysis, the higher mean RAP (β = 0.52; p < 0.0001), the presence of significant tricuspid regurgitation (β = 0.31; p = 0.0005), a larger body surface area (β = 0.22; p = 0.0017), and younger age (β = -0.18; p = 0.049) were independently associated with the IVC maximum diameter. Only the mean RAP was independently associated with the IVCCI (β = -0.45; p < 0.0001). The regression equation (R2 = 0.43, p < 0.0001) was as follows: estimated mean RAP = 3.7 + 0.62 × maximum IVC diameter / BSA - 0.07 × IVCCI. ConclusionDistension of the IVC mainly occurs with elevated RAP. However, the presence of significant tricuspid regurgitation, a larger body surface area, and younger age are associated with the IVC maximum diameter, independently of RAP. Interestingly, IVCCI is influenced only by RAP.

Inferior Vena Cava Collapsibility Index and Central Venous Pressure for Fluid Assessment in the Critically Ill Patient.

To determine the correlation of sonographic evaluation of inferior vena cava diameter and its collapsibility index with central venous pressure in both spontaneously breathing and mechanically ventilated patients in surgical ICU. Study Design: Cross-sectional study. Surgical ICU, Lahore General Hospital from November 2020 to May 2021. All patients above 18 years of age, who had central venous catheter placed, were included in the study. Patients with raised abdominal pressure, pregnancy, morbid obesity, heart diseases, and those unable to lie in supine position, were excluded. For inferior vena cava (IVC) measurement, IVC was visualised using curvilinear probe of ultrasound machine. Minimum and maximum diameters of inferior vena cava were calculated in every respiratory phase. IVC collapsibility index was expressed in percentage. Central venous pressure (CVP) was recorded soon after IVC measurement, using manometer. Total number of patients was 126. A significant correlation was seen between IVC measurements (inferior vena cava diameters and the collapsibility index) and CVP, (p<0.001), but the regression coefficients were less in patients who were mechanically ventilated (r=0.779 for IVC maximum diameter and -0.725 for collapsibility index) than the patients who were breathing spontaneously (r=0.850 for IVC maximum diameter and -0.899 for collapsibility index) Conclusion: Evaluation of IVC diameter and its collapsibility index is an easy and non-invasive method to evaluate intravascular volume status of critically ill patients. Its use is more helpful in patients who are spontaneously breathing than those who are mechanically ventilated. Key Words: Central venous pressure, Fluid status, Inferior vena cava diameter.

Prediction of post-induction hypotension in young adults using ultrasound-derived inferior vena cava parameters: An observational study.

Background and Aims:Inferior vena cava (IVC) diameter and its respiratory variability have been shown to predict post-induction hypotension with high specificity in a mixed population of patients. We assessed whether these parameters could be as reliable in healthy adult patients as in a mixed patient population.Methods:In the present prospective observational study, 110 patients of either sex, aged between 18 and 50 years, belonging to American Society of Anesthesiologists class I and II, fasted as per the institutional protocol and scheduled for elective surgery under general anaesthesia were enroled. Prior to induction, ultrasound examination of IVC was done and variation in IVC diameter with respiration was assessed. Maximum and minimum IVC diameters [(dIVCmax) and (dIVCmin), respectively] over a single respiratory cycle were measured and collapsibility index (CI) was calculated. Vitals were recorded just before induction and at every minute after induction for 10 min. Episodes of hypotension (mean arterial pressure [MAP] <65 mmHg or fall in MAP >30% from baseline) during the observation period were recorded. The receiver operating characteristic (ROC) curve was constructed for determining optimum cut-off with sensitivity and specificity of IVC diameters and CI for development of hypotension.Results:IVC was not visualised in 22 patients. Out of the remaining 88 patients, 17 (19.3%) patients developed hypotension after induction. The dIVCmax, dIVCmin and CI were comparable between patients who developed and who did not develop hypotension. The area under curve of ROC for CI, dIVCmax and dIVCmin was 0.51, 0.55 and 0.52, respectively, with optimum cut-off value of 0.46, 1.42 and 0.73, respectively.Conclusion:Ultrasound-derived IVC parameters demonstrate poor diagnostic accuracy for prediction of hypotension after induction in healthy adult patients.

Sonographic Estimation Rather Than Quantification of Fluid Status Using Inferior Vena Cava and Other Major Vessel Parameters in a Non-Bleeding Fluid Loss and Centralization Model.

ObjectiveA well-accepted step in emergency sonography is the estimation of a fluid deficit through Inferior Vena Cava (IVC) diameter variability with known cut-offs especially in bleeding. We sought to answer, whether a non-bleeding fluid deficit can be quantified through sonographic assessment of IVC diameter variability and related aortic parameters. Sport divers were used as human hypovolemic vasoconstriction models since immersion is known to cause relevant volume depletion through vasoconstriction and induced diuresis.Materials and MethodsForty-one sport divers performed 342 single and repetitive dives to account for intra- and interindividual variability and were assessed for inferior Vena Cava and neighboring aortic diameters as well as their cardiac/respiratory variations. Dive-related weight loss was measured together with sonographic vessel diameter changes inferior to the right atrium.ResultsHighest correlation with dive-related weight loss of max. 2.9 kg per an average 47 minutes dive was found with r=0.34 for the difference of IVC maximum diameter related to minimum Aortic diameter. Single or combined parameters, as well as Collapsibility Index, showed lower or no correlations. Vascular parameters were able to explain 7.5% of the variance of fluid losses, whereas interindividual effects explained 10%. The remaining 82.5% is of mixed intraindividual counterregulatory effects.ConclusionIVC diameter changes in immersion-induced hypovolemic centralization provides qualitative information on relevant fluid loss only. Confounding factors like inter and intraindividual variability prevent a sufficient correlation for useful quantification of the experienced non-bleeding fluid deficit in the clinical setting.

Prognostic Value of Liver Stiffness Measured by Two-Dimensional Elastography in Acute Decompensated Heart Failure with Preserved Ejection Fraction.

Liver stiffness (LS) assessed by ultrasound elastography reflects right-sided filling pressure and offers additional prognostic information in patients with acute decompensated heart failure (ADHF). However, the prognostic value of LS in heart failure (HF) with preserved ejection fraction (HFpEF) remains unclear. This study aimed to investigate the prognostic value of LS measured by two-dimensional shear wave elastography (2D-SWE) in patients with HFpEF.We prospectively enrolled 80 patients hospitalized for decompensated HFpEF between September 2019 and June 2020. Patients were categorized into three groups based on the tertile values of LS at discharge.The third tertile LS group had an older age; more advanced New York Heart Association functional class; higher total bilirubin, γ-glutamyl transferase (GGT), N-terminal pro-B type natriuretic peptide (NT pro-BNP), and Fibrosis-4 index; a larger right ventricle diastolic diameter, higher tricuspid regurgitation pressure gradient, and a larger maximal inferior vena cava diameter. During a median [interquartile range] follow-up period of 212 (82-275) days, 25 (31.2%) patients suffered composite end points (all-cause mortality and rehospitalization for worsening HF). The third tertile LS group had a significantly higher rate of composite end points (log-rank P = 0.002). A higher LS and the third tertile LS were significantly associated with the composite end points, even after adjusting for a conventional validated HF risk score and other previously reported prognostic risk factors.Increased LS measured by 2D-SWE reflects the severity of liver impairment by liver congestion and fibrosis, underlying right HF, and provides additional information for the prediction of poor outcomes in HFpEF.

Ultrasound evaluation of inferior vena cava compression in tilted and supine term parturients.

Hypotension is common following spinal anesthesia (SA) during elective Cesarean delivery (CD). Although common practice is to alleviate inferior vena cava (IVC) compression, limited evidence supports a 15° tilt for CD. We measured collapsibility of the IVC in supine and 15° left lateral tilt positions with ultrasound before and after SA and phenylephrine infusion in term parturients. Twenty term parturients scheduled for CD were recruited for this prospective study. Ultrasound measurements of the IVC were taken 1) supine before SA, 2) tilted 15° before SA, 3) supine after SA, and 4) tilted 15° after SA. A phenylephrine infusion was begun after injection of SA. The primary outcome was to evaluate the impact of position on the IVC collapsibility index (IVCCI): a measure of the difference between the maximum and minimum IVC diameter with respiration. The mean (standard deviation) IVCCI (%) before SA was higher in the supine 19.5 (8.0) than in the tilted 15.0 (6.4) position (mean difference, 4.5; 95% confidence interval [CI], 0.1 to 8.9; P = 0.04). After SA, there was no significant difference between IVCCI (%) in the supine 17.8 (8.3) and tilted 14.2 (6.9) position (mean difference, 3.5; 95% CI, -0.9 to 7.9; P = 0.13). There was no correlation between the pre-spinal IVVCI measurements and the quantity of phenylephrine used during the surgery. The IVCCI was lower in the 15° tilt position than in the supine position, but not after SA with a phenylephrine infusion. Ultrasound imaging can help identify IVC compression. www.clinicaltrials.gov (NCT03410199); registered 18 January 2018.

The relationship between collapsibility index of inferior vena cava and hypotension after spinal anesthesia

Objectives: Hypotension is a common complication of spinal anesthesia. Imaging of inferior vena cava (IVC) and measurement of the IVC-collapsibility index (IVC-CI) by ultrasonography (USG) has been a widely used non-invasive, easy and reliable method for measurement of the fluid imbalance. In the present study, we aimed to investigate the predictive ability of the maximum IVC diameter (dIVCmax) and IVC-CI for hypotension after spinal anesthesia. Methods: The study was designed as prospective and observational. One hundred thirty-two patients aged 18-75 years with ASA I-II underwent inguinal hernia surgery with spinal anesthesia and recruited to the study. Maximum and minimum (dIVCmin) IVC diameters were measured. IVC-CI (%) was quantified according to the formula of [(dIVCmax - dIVCmin)/dIVKmax] × 100%. Results: The patients were grouped as hypotensive and non-hypotensive. In fifty-seven patients of 120 cases (47.5%), hypotension has emerged following spinal anesthesia. No significant differences in dIVCmax and IVC-CI were recorded between the study groups (p &amp;gt; 0.05). There were significant inverse correlation between age and IVC-CI. Significant positive correlation between the lowest values of the systolic arterial pressure, diastolic arterial pressure, mean arterial pressure and IVC-CI and significant positive correlation between dIVCmax and diastolic blood pressure, maximum and minimum values of the mean arterial pressure. Conclusions: We found that dIVCmax and IVC-CI values measured before spinal anesthesia were not sufficient parameters enough to predict hypotension after spinal anesthesia. Further studies investigating the IVC measurements under spinal anesthesia together with dynamic hemodynamic monitorization modalities are needed.

Inferior Vena Cava Collapsibility Index: Clinical Validation and Application for Assessment of Relative Intravascular Volume.

Accurate assessment of relative intravascular volume is critical to guide volume management of patients with acute or chronic kidney disorders, particularly those with complex comorbidities requiring hospitalization or intensive care. Inferior vena cava (IVC) diameter variability with respiration measured by ultrasound provides a dynamic noninvasive point-of-care estimate of relative intravascular volume. We present details of image acquisition, interpretation, and clinical scenarios to which IVC ultrasound can be applied. The variation in IVC diameter over the respiratory or ventilatory cycle is greater in patients who are volume responsive than those who are not volume responsive. When 2 recent prospective studies of spontaneously breathing patients (n=214) are added to a prior meta-analysis of 181 patients, for a total of 7 studies of 395 spontaneously breathing patients, IVC collapsibility index (CI) had a pooled sensitivity of 71% and specificity of 81% for predicting volume responsiveness, which is similar to a pooled sensitivity of 75% and specificity of 82% for 9 studies of 284 mechanically ventilated patients. IVC maximum diameter <2.1 cm, that collapses >50% with or without a sniff is inconsistent with intravascular volume overload and suggests normal right atrial pressure (0-5 mmHg). Inferior vena cava collapsibility (IVC CI)<20% with no sniff suggests increased right atrial pressure and is inconsistent with overt hypovolemia in spontaneously breathing or ventilated patients. These IVC CI cutoffs do not appear to vary greatly depending on whether patients are breathing spontaneously or are mechanically ventilated. Patients with lower IVC CI are more likely to tolerate ultrafiltration with hemodialysis or improve cardiac output with ultrafiltration. Our goal for IVC CI generally ranges from 20% to 50%, respecting potential biases to interpretation and overriding clinical considerations. IVC ultrasound may be limited by factors that affect IVC diameter or collapsibility, clinical interpretation, or optimal visualization, and must be interpreted in the context of the entire clinical situation.

Normative data for inferior vena cava diameters and collapsibility index in healthy Indian children from a tertiary care hospital of Chennai

Background: An ultrasound evaluation of the inferior vena cava (IVC) collapsibility index (CI) has proven to be an excellent noninvasive method of evaluating hydration in adult patients. There is a lack of normative data on the IVC diameters and CI in Indian children. This study was planned to formulate the normative values for IVC diameter in children and adolescents and to assess its correlation with various somatic parameters in Indian children aged 6 months–16 years. Subjects and Methods: Children aged 6 months–16 years in good general health, normal hydrations, and without any significant underlying medical condition who were coming to hospital for their treatment in the outpatient department were consecutively enrolled in the study. The maximum and minimum diameters of IVC were measured during the expiratory and inspiratory phase of the respiratory cycle, respectively, using M mode ultrasonography. CI was also calculated for each subject. These values were correlated with age, gender, and body surface area (BSA). Results: One hundred patients were enrolled in the study, 48 were boys and 52 were girls. The mean (standard deviation) CI was 23.3% (11.9) among males and 20.1% (11.7) among females. The mean maximum and minimum IVC diameter increased significantly with age (r = 0.738, P = 0.00; r = 0.789 P = 0.000) and with BSA (r = 0.73, P = 0.0001; r = 0.77, P = 0.0001). CI did not show significant correlation with age or BSA. Conclusion: IVC dimensions during inspiration or expiration increases with age and BSA, but same relation does not hold for CI. These values were similar among males and females.

Inferior Vena Cava Collapsibility Index to Assess Central Venous Pressure in Perioperative Period Following Cardiac Surgery in Children

The inferior vena cava collapsibility index (IVCCI) is an ultrasound method used to assess central venous pressure (CVP). Our objective was to evaluate the correlation between IVCCI and CVP in children during the early period following surgery for congenital heart disease (CHD). Prospective study performed in a single tertiary care center. Patients ≤ 18years old, who underwent cardiopulmonary bypass surgery for CHD, were enrolled. Ultrasound images of the inferior vena cava (IVC) were obtained at two time points; the first was within 2h of arrival to the CICU and the second was 12-18h from the first measurement. CVP measured by catheter placed during surgery was recorded within minutes of performing ultrasound. Maximum and minimum IVC diameters were measured by 2D images and M mode method. Seventy patients (47.1% males), with median age 7months (IQR 4-47months) and weight 6.9kg (IQR 4.8-13.5kg), were evaluated. The 2D IVCCI had inverse correlation with CVP in patients breathing spontaneously; r = - 0.76 (p < 0.01) and r = - 0.73 (p < 0.01), during the first and second measurements, respectively. The 2D IVCCI ≤ 0.24 had sensitivity, specificity, and negative predictive value of 94%, 79%, and 88.9% , respectively, to detect CVP ≥ 10mmHg. No correlation was found between IVCCI and CVP during positive pressure ventilation. There is a significant inverse correlation between 2D IVCCI and CVP in spontaneously breathing children after surgery for CHD. Use of 2D IVCCI for monitoring CVP could reduce the frequency and duration of CVP catheters and their inherent complications.

Inferior Venacaval Ultrasonography to Detect Pre-Operative Hypovolemia as a Predictor of Postinduction Hypotension

Background: Hypotension is a common side effect of general anaesthesia, and when severe, it may lead to adverse outcomes. Ultrasonography of Inferior Vena Cava (IVC) is an effective, non-invasive method of assessment of intravascular volume status and hence the risk of hypotension at induction of anaesthesia. This study investigated whether preoperative ultrasound guided IVC measurements could predict hypotension after induction of anaesthesia. Methods: After ethical committee approval, this study was conducted at Sri Ramakrishna Hospital, Coimbatore. Written and informed consent was obtained. Forty six (46) adult patients, conforming to American Society of Anaesthesiologists physical status I to II, scheduled for elective surgery under general anaesthesia were recruited. Maximum IVC Diameter (dIVCmax) and Collapsibility Index (CI) were measured preoperatively. Before induction, Mean Blood Pressure (MBP) was recorded. After induction, MBP was recorded for 10 consecutive minutes. Hypotension was defined as greater than 30% decrease in MBP from baseline or MBP less than 60 mmHg. Results: IVC could not be visualized in 6 patients. Data from remaining 40 patients were analysed, of whom 26 patients (65%) developed hypotension. The incidence of hypotension in patients with CI>40% was 100% and when CI<40% it was 4%. The mean value of IVC maximum diameter was 1.60 cm and the mean value of IVC minimum diameter was 1.02 cm. The optimal cut-off value was 40% for CI among the patients who developed hypotension. CI was positively associated with a percentage decrease in MBP. Conclusion: Preoperative ultrasound IVC-CI measurement is a reliable predictor of hypotension after induction of general anaesthesia, and CI greater than 40% was highly significant in causing post induction hypotension.

Role of Inferior Vena Cava Parameters as Predictors of Fluid Responsiveness in Pediatric Septic Shock: A Prospective Study

AbstractFluid resuscitation is the initial therapy for septic shock worldwide. Prediction of fluid responsiveness is essential for optimizing fluid administration. Only few pediatric studies have evaluated the role of inferior vena cava (IVC) as a reliable predictor of fluid responsiveness. The aim of this study was to evaluate the role of IVC parameters as predictors of fluid responsiveness in children (under the age of 5 years) having septic shock at different times from admission. A prospective observational study included 51 children having septic shock. It was conducted in the nine-bedded pediatric intensive care unit of a university hospital from January 1, 2018, to the August 31, 2018. Echocardiography was used to assess minimal and maximal IVC diameters and its distensibility index with simultaneous assessment of stroke volume (SV), at 1, 6, and 24 hours from admission. The decision to give fluid in these children was thereby based on the presence of at least one sign of inadequate tissue perfusion. SV was reassessed directly after administration of a fluid bolus of 10 mL/kg over 10 minutes. Fluid responsiveness was considered adequate when there was ≥ 10% increase in SV after fluid bolus. Minimal IVC diameter indexed to body surface area and its distensibility index can be predictors of fluid responsiveness at all times: 1 hour (area under curve [AUC] = 0.88; 95% confidence interval [CI] = 0.77–0.96), 6 hours (AUC = 0.86; 95% CI = 0.67–0.97), and 24 hours (AUC = 0.77; 95% CI = 0.6–0.95). IVC distensibility index can also predict fluid responsiveness at 1 hour (AUC= 0.87; 95% CI = 0.74–0.95), 6 hours (AUC = 0.86; 95% CI = 0.73–0.94), and 24 hours (AUC = 1; 95% CI = 0.77–1). The cutoff points of each parameter differed from time to time (contradicts with previous statement that says it is predictor at all times). The maximum IVC diameter could not predict fluid responsiveness at any time from admission. Minimal IVC diameter and its distensibility index were feasible noninvasive surrogates of fluid responsiveness in pediatric septic shock at different times from admission.

Decreased Stroke Volume and Venous Return in School Children with Postural Tachycardia Syndrome.

In postural tachycardia syndrome (POTS), a subtype of orthostatic intolerance, the changes in hemodynamics due to postural changes are poorly understood. We speculated that inappropriate venous return, which may occur in the upright position in patients with school-aged POTS, could be detected by echocardiography. Our prospective study was conducted with 100 POTS patients (45 boys and 55 girls), aged 13.1 ± 1.5 years and 52 age- and sex-matched healthy subjects (control). Echocardiography was performed in the supine and sitting positions. Cardiac parameters [stroke volume index, cardiac index, heart rate, and the maximum inferior vena cava diameter (max IVC)] were evaluated in addition to pulse pressure. Unlike the control subjects, POTS patients demonstrated decreased stroke volume index (P = 0.02) and max IVC (P < 0.01) irrespective of posture. The rates of max IVC change did not differ between control and POTS groups. The enrolled POTS patients were divided into two subgroups [dilatation (n = 57) and contraction (n = 43)] based on whether the change rate of max IVC was less than zero or not. The contraction group showed a significantly higher heart rate than the dilatation group with respect to posture (P = 0.03), indicating the poor response of peripheral vessels in the lower limbs only in the contraction group. In conclusion, echocardiographic assessment detected decreased stroke volume and venous return in POTS. The changes in max IVC in response to postural changes may indicate an underlying pathophysiology in POTS.

A Predictive Model for Tumor Invasion of the Inferior Vena Cava Wall Using Multimodal Imaging in Patients with Renal Cell Carcinoma and Inferior Vena Cava Tumor Thrombus.

Purpose Developed a preoperative prediction model based on multimodality imaging to evaluate the probability of inferior vena cava (IVC) vascular wall invasion due to tumor infiltration. Materials and Methods We retrospectively analyzed the clinical data of 110 patients with renal cell carcinoma (RCC) with level I-IV tumor thrombus who underwent radical nephrectomy and IVC thrombectomy between January 2014 and April 2019. The patients were categorized into two groups: 86 patients were used to establish the imaging model, and the data validation was conducted in 24 patients. We measured the imaging parameters and used logistic regression to evaluate the uni- and multivariable associations of the clinical and radiographic features of IVC resection and established an image prediction model to assess the probability of IVC vascular wall invasion. Results In all of the patients, 46.5% (40/86) had IVC vascular wall invasion. The residual IVC blood flow (OR 0.170 [0.047-0.611]; P = 0.007), maximum coronal IVC diameter in mm (OR 1.203 [1.065-1.360]; P = 0.003), and presence of bland thrombus (OR 3.216 [0.870-11.887]; P = 0.080) were independent risk factors of IVC vascular wall invasion. We predicted vascular wall invasion if the probability was >42% as calculated by: {Ln [Pre/(1 − pre)] = 0.185 × maximum cornal IVC diameter + 1.168 × bland thrombus–1.770 × residual IVC blood flow–5.857}. To predict IVC vascular wall invasion, a rate of 76/86 (88.4%) was consistent with the actual treatment, and in the validation patients, 21/26 (80.8%) was consistent with the actual treatment. Conclusions Our model of multimodal imaging associated with IVC vascular wall invasion may be used for preoperative evaluation and prediction of the probability of partial or segmental IVC resection.