Estimation Of Central Venous Pressure Research Articles

Portal vein pulsatility: An important sonographic tool assessment of systemic congestion for critical ill patients

In this editorial we comment on the article by Kuwahara et al , published in the recent issue of the World Journal of Cardiology . In this interesting paper, the authors showed a correlation between portal vein pulsatility ratio, examined by bedside ultrasonography, and prognosis of hospitalized patients with acute heart failure. Systemic congestion is being notoriously underdetected in the acutely ill population with conventional methods like clinical examination, biomarkers, central venous pressure estimation and X-rays. However, congestion should be a key therapeutic target due to its deleterious effects to end organ function and subsequently patient prognosis. Doppler flow assessment of the abdominal veins is gaining popularity worldwide, as a valuable tool in estimating comprehensively congestion and giving a further insight into hemodynamics and patient management.

Positive correlation between echocardiographic tricuspid E peak velocity and central venous pressure in dogs: A preliminary study.

In the absence of vascular obstruction, central venous pressure (CVP) is a hydrostatic pressure in the cranial and caudal vena cava, providing valuable information about cardiac function and intravascular volume status. It is also a component in evaluating volume resuscitation in patients with septic shock and monitoring patients with right heart disease, pericardial disease, or volume depletion. Central venous pressure is calculated in dogs by invasive central venous catheterization, which is considered high-risk and impractical in critically ill patients. This study aimed to investigate the feasibility of using echocardiographic tricuspid E/E' as a noninvasive method to estimate CVP in anesthetized healthy dogs under controlled hypovolemic conditions. Ten male mixed-breed dogs were included in the study after a thorough health assessment. For hypovolemia induction, blood withdrawal was performed, and echocardiographic factors of the tricuspid valve, including peak E and E' velocities, were measured during CVP reduction. Repeated measures analysis of variance and Bonferroni post hoc tests were employed to compare the average difference between measured echocardiographic indices and CVP values derived from catheterization and intermittent measurement methods. Spearman's ρ correlation coefficient was used to evaluate the correlation between echocardiographic indices and CVP. E peak velocity had a significant negative correlation with venous blood pressure phases (r=-0.44, P=.001), indicating a decrease in peak E velocity with progressive CVP reduction. However, tricuspid valve E' peak velocity and E/E' did not correlate with CVP, suggesting that these parameters are not reliable for CVP estimation in dogs.

Correlation between echocardiographic estimation of right atrial pressure and invasive measurement of central venous pressure in postoperative pediatric patients with congenital heart disease: a prospective observational study

BackgroundRight atrial pressure plays a critical role as a hemodynamic parameter in diagnosing pulmonary hypertension and other cardiac diseases, as well as guiding the treatment and prognosis of various cardiac disorders. If there is no obstruction between the inferior or superior vena cava (SVC) as central veins and the right atrium, the pressures in these veins could be considered equal to the right atrial pressure. This study aimed to examine the correlation between echocardiographic methods for estimating right atrial pressure and invasive measurements of central venous pressure (CVPi) in infants and children with congenital heart disease during the 48 h after cardiac surgery and to establish regression equations for echocardiographic estimation of central venous pressure (CVPe).ResultsWe prospectively enrolled 43 infants and children, ranging in age from 6 months to 16 years, including 20 males and 23 females. We found a significant correlation between CVPi and the ratio of the maximal diameter of IVC to the maximal diameter of the descending aorta ratio (IVCmax/DAOmax) (r = 0.529, P < 0.001), SVCS/D velocity ratio (SVCS/D) (r = 0.462, P = 0.006), right atrial vertical diameter (RAVD) (r = 0.409, P = 0.01), area (r = 0.384, P = 0.014), and tricuspid valve A wave acceleration rate (TVAAR) (r = 0.315, P = 0.048). Multiple regression analysis yielded an equation for estimating central venous pressure using four parameters related to the IVC, SVC, tricuspid valve, and right atrium. The equation is as follows: estimated CVP = 4.36 + (2.35 × IVCmax/DAOmax) + (1.06 × SVCS/D) + (0.059 × RAVD) + (0.001 × TVAAR). This equation is strongly correlated with CVPi (Pearson r = 0.698, P = 0.002).ConclusionsThe estimation of central venous pressure through a multi-parametric equation that included the ratio of the maximal diameter of the inferior vena cava to the maximal diameter of the descending aorta, the ratio of S to D velocity of the superior vena cava, the vertical diameter of the right atrium, and the acceleration rate of the A wave of the tricuspid valve demonstrated a robust correlation with invasively measured central venous pressure. To assess the accuracy of predicted pressures by this equation, further investigations are required to apply this innovative multi-parametric formula to a prospective population of pediatric patients with congenital heart disease.

Reliability of transient elastography as a noninvasive method for estimating central venous pressure in adult patients after a Fontan procedure

BackgroundIn adult patients, after a Fontan procedure, high central venous pressure (CVP) is a hemodynamic risk factor associated with poor prognosis. High liver stiffness (LS) on transient elastography (TE) is associated with high CVP in patients with heart failure without liver disease. Here, we investigated whether LS assessment using TE is a reliable method to noninvasively evaluate CVP in adult patients after a Fontan procedure, who can present varying degrees of liver fibrosis as a complication. MethodsWe measured LS using TE and CVP by cardiac catheterization in 24 adult patients who had undergone a Fontan procedure. The estimated CVP was calculated using the previously reported formula: −5.8 + 6.7 × ln[LS]. We examined the correlation between LS and CVP, and degree of agreement between the estimated and measured CVPs. Patients were divided into two groups, with or without suspected liver cirrhosis, based on abdominal imaging studies. ResultsThe median patient age was 35 years (interquartile range 25, 39). Overall, there was a strong correlation between LS and CVP (ρ = 0.83, p < 0.001). The estimated CVP based on LS and the CVP measured using cardiac catheterization were positively correlated; however, the estimated CVP tended to be higher than the measured CVP (mean difference 0.9 mmHg [95% limits of agreement: −2.8 to 4.6 mmHg]). These results were consistent across all groups. ConclusionsIn adult patients after a Fontan procedure, LS measured by TE showed a positive correlation with CVP by cardiac catheterization. TE can be useful as a noninvasive estimation of CVP.

Central venous pressure estimation with force-coupled ultrasound of the internal jugular vein

We estimate central venous pressure (CVP) with force-coupled ultrasound imaging of the internal jugular vein (IJV). We acquire ultrasound images while measuring force applied over the IJV by the ultrasound probe imaging surface. We record collapse force, the force required to completely occlude the vein, in 27 healthy subjects. We find supine collapse force and jugular venous pulsation height (JVP), the clinical noninvasive standard, have a linear correlation coefficient of r2 = 0.89 and an average absolute difference of 0.23 mmHg when estimating CVP. We perturb our estimate negatively by tilting 16 degrees above supine and observe decreases in collapse force for every subject which are predictable from our CVP estimates. We perturb venous pressure positively to values experienced in decompensated heart failure by having subjects perform the Valsalva maneuver while the IJV is being collapsed and observe an increase in collapse force for every subject. Finally, we derive a CVP waveform with an inverse three-dimensional finite element optimization that uses supine collapse force and segmented force-coupled ultrasound data at approximately constant force.

Abstract 15532: Pressure Measurement From a Peripheral Iv Correlates Well With Invasive Central Venous Pressure Measurement

Introduction: Despite its importance in cardiac patients, accurate central venous pressure (CVP) estimation remains a challenge. Noninvasive methods, such as jugular venous pressure measurement, are highly dependent on examiner experience, and the gold-standard invasive methods require procedures that carry risk of complication. Recent studies suggest that pressure measurement directly from a patient’s peripheral intravenous (IV) catheter, termed peripheral venous pressure (PVP), appears promising as an accurate and noninvasive method for CVP estimation. Methods: To be included in the study, patients were either receiving right heart catheterization (RHC) or had an existing pulmonary artery catheter (PAC) in place. CVP was measured using standard technique either during RHC or at bedside from the PAC. The same pressure tubing was then connecting to the patient’s existing IV, regardless of the location or catheter gauge, for measurement of the PVP. Results: Seventeen patients were prospectively enrolled. The majority (70.6%) had their CVP and PVP measured during RHC. In the overall cohort, 35.3% were on mechanical circulatory support, and 29.4% were on inotropes at the time of measurement. CVP and PVP measurements were significantly correlated with one another (Pearson’s r = 0.73, p &lt; 0.001; Figure 1A). Sensitivity analysis was performed to exclude one notable outlier, which strengthened the correlation (Pearson’s r = 0.91, p &lt; 0.001; Figure 1B). Conclusions: This data suggests that PVP is a promising and simple method for the noninvasive estimation of CVP.

Evaluation of ultrasonography measurement of superior vena cava diameter in comparison to central venous pressure in guiding of fluid therapy in patients with hypovolemic shock

Invasive placement of a central venous catheter is the norm for measuring central venous pressure (CVP), which is essential in perioperative care (CVC). Clinical evaluation of the jugular venous pressure allows for a non-invasive estimation of CVP. Superior vena cava (SVC) diameter and collapsibility with breathing have been emphasised in echocardiographic estimates of CVP. The goal of this study is to compare CVP values to ultrasound measurements of SVC diameter and collapsibility index in directing fluid treatment for patients with hypovolemic shock. On admission, patients underwent hemodynamic monitoring of intravascular volume by measuring central venous pressure, taking a non-invasive blood pressure reading, and calculating urine output. Additionally, SVC ultrasonography was used to determine the diameter and collapsibility of the saphenous vein. Conclusions Patients with a central venous pressure (CVP) of 10 or higher had substantially greater values for their SVC maximum and minimum, and smaller values for their SVC coefficient of variation (CI). There was a positive association between CVP and maximum and minimum dSVC, and a negative correlation between CVP and SVC-CI. The optimal SVC-CI cutoff for separating patients with and without CVP10 was 36%, with a sensitivity of 27% and a specificity of 87.5 %. Independent predictors of CVP10 were shown to be lower SVC-CI, which aided in the decision to discontinue fluid infusion. Overall, the CVP is still the gold standard for guiding fluid resuscitation in the critically unwell. Estimating CVP non-invasively by measuring SVC diameter and collapsibility during positive pressure breathing seems intriguing. Predicting high CVP using SVC-CI might help you decide when to stop giving the patient fluids.

Ultrasound-guided venous pressure measurement.

Current standard technique for venous pressure measurement is still invasive, requiring insertion of a catheter. Additionally, clinical estimation of central venous pressure (CVP) has proven unreliable compared to invasive methods. Meanwhile, different non-invasive ultrasound guided modalities may provide a valid alternative to invasive venous pressure measurement. Particularly promising is a novel compression ultrasound (CUS) which combines ultrasound properties with a tissue pressure manometer enabling even further future applications. This review provides an overview using ultrasound guided non-invasive venous pressure measurement (UGPni) in clinical trials so far and focuses on three objectives: (1) To summarize the main methods using UGPni for central venous pressure measurement (2) To outline the key findings of previous clinical trials for UGPni regarding CVP measurement with primary focus on novel compression ultrasound of a forearm vein (3) To point out limitations and possible future clinical implications of these ultrasound modalities UGPni represents an easy-to-perform and safe alternative to invasive "gold standard" diagnostic tools for measuring central venous pressure. After a brief introduction, non-specialist personnel using a portable ultrasound device can apply this method in a feasible way. Of all mentioned methods in this review CUS is the method of choice underscoring its ability to assess a patient's CVP categories correctly. Furthermore, detection of non-invasive central venous pressure in the emergency room represents an independent predictor for cardiac rehospitalization in patients with decompensated heart failure, thus helping in risk stratification as well as being an additive tool in general hemodynamic management of critically ill patients. This review concludes a significant role for ultrasound guided non-invasive venous pressure measurement suitable for a wide range of everyday clinical practice. However, further studies are warranted to proof a causal relationship in this regard.

Jugular Venous Pressure Measurement Is Accurate When Performed By Attending Physicians On Internal Medicine Wards

<h3>Introduction</h3> Jugular venous pressure (JVP) is a widely used estimate of central venous pressure (CVP). It is unclear how accurate JVP measurement is by physicians in different stages of clinical practice. We investigated the accuracy of JVP measurement across different levels of medical training by comparing JVP measurements to the peripheral venous pressure (PVP) measurement, which has been shown to have a high degree of correlation to CVP measurements. <h3>Hypothesis</h3> JVP will be better correlated with CVP when measured by physicians of higher level of clinical training. <h3>Methods</h3> A prospective, cross-sectional study in which 82 participants (13 third or fourth-year medical students, 26 interns, 21 residents, and 22 attending internal medicine physicians) measured JVP in patients admitted for acute decompensated heart failure (ADHF) to the general medicine ward. JVP measurements were compared to the PVP measured from a peripheral intravenous catheter by standard technique. <h3>Results</h3> Forty-five patients were enrolled with a mean age of 69±14 years, mean body mass index (BMI) of 31±9 kg/m², mean ejection fraction (EF) of 47±20%, and mean B-type natriuretic peptide (BNP) of 1242±1161 pg/ml. Mean JVP was 8.6 (4-18) cmH₂O for medical students, 8.7 (4-16) cmH₂O for interns, 9.1 (5-20) cmH₂O for residents, and 9.2 (4-15) cmH₂O for attending physicians. Mean PVP was 8.7 (1-20) mmHg. The JVP and CVP were found to have a moderate correlation (r=0.42, p=0.005) for attending physicians and a low correlation for medical students or residents. High-degree correlation among attending physicians was noted in patients with EF < 50% (r=0.60, p=0.009), BMI < 30 (r=0.55, p=0.008) and BNP > 1000 (r=0.56, p=0.01). <h3>Conclusions</h3> JVP is a reliable estimation of volume status in those admitted with ADHF when examined by an attending-level internal medicine physician, specifically in patients with a low BMI, low EF, and a high BNP.

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.

Accuracy of Ultrasound Jugular Venous Pressure Height in Predicting Central Venous Congestion.

Assessment of volume status through the estimation of central venous pressure (CVP) is integral in the care of heart failure (HF). Bedside assessment is limited by obesity, variation in physical examination skills, and expertise in ultrasonography. To validate the accuracy of quantitative and qualitative point-of-care ultrasonography assessment of jugular venous pressure (JVP) in predicting elevated CVP. Prospective observational study using convenience sampling. 2 U.S. academic hospitals. Adult patients undergoing right heart catheterization between 5 February 2019 and 1 March 2021. Estimation of the JVP height by handheld ultrasound device (uJVP), JVP by traditional physical examination, and qualitative presence of a distended uJVP in the upright position (upright-uJVP) was done before invasive measurements. Receiver-operating characteristic analysis of the uJVP was compared with invasive hemodynamics. In 100 participants undergoing right heart catheterization for HF indications (mean age, 59.6 years; 44% with preserved ejection fraction), the uJVP in a reclined position accurately predicted elevated right atrial pressure (RAP) (>10 mm Hg), with an area under the curve of 0.84. A positive uJVP in the upright position was 94.6% specific for predicting elevated RAP. Limited examiners, only 2 centers, and convenience sampling. Point-of-care ultrasonography assessment of the uJVP is feasible, reproducible, and accurately predictive of elevated CVPs in patients undergoing right heart catheterization. Further investigation of clinical application of ultrasound-measured JVP seems warranted. None.

Volume status and arterial stiffness evaluation in peritoneal dialysis patients.

Arterial stiffness represents an independent risk factor for cardiovascular mortality in dialysis patients and is strongly connected to hypervolemia. The aim of the study was to evaluate different methods for fluid status assessment and their association with arterial stiffness parameters in peritoneal dialysis patients. In 16 peritoneal dialysis patients (53 ± 18 years, 9/16 men) fluid status was determined by clinical examination, lung ultrasound (number of B-lines, normal up to 4), overhydration degree by bioimpedance monitor device, estimation of central venous pressure by ultrasound measurement of vena cava inferior, measurement of serum N-terminal pro b-type natriuretic peptide (NT-proBNP), and albumin level. Pulse wave velocity and augmentation index were measured non-invasively with an oscillometric device to indirectly assess arterial stiffness, blood pressure (BP) was obtained by the same device. Clinical evaluation (BP 136 ± 15/93 ± 15 mmHg, edema in 2/16 patients) and lung ultrasound (on average 3 ± 6 B-lines) showed mostly normal fluid status of patients. Patients had slightly lower albumin values (37 ± 4 g/L), slightly elevated central venous pressure (10 ± 4 mmHg), and elevated NT-proBNP (11,596 ± 13,635 ng/L). Body composition evaluation showed mild overhydration (1.5 ± 2 L), which significantly correlated with central venous pressure (p = 0.046) and NT-proBNP (p = 0.004). Lung ultrasound significantly negatively correlated with albumin (r = -0.82, p < 0.001) and positively with NT-proBNP (r = 0.62, p = 0.011). Augmentation index (22 ± 11%) and augmentation pressure correlated with lung ultrasound (r = 0.54, p = 0.032 and r = 0.67, p = 0.004, respectively), although pulse wave velocity (8.4 ± 2.5 m/s) showed no significant correlation with fluid status parameters. The multivariate model showed that lung ultrasound B-lines were an independent determinant of augmentation pressure (β = 0.58, p = 0.043). Fluid status evaluated with lung ultrasound showed good correlation with augmentation index and augmentation pressure, which are markers of arterial stiffness. The lung ultrasound B-lines were found to be an independent determinant of augmentation pressure. Overall arterial stiffness evaluated with pulse wave velocity and augmentation index was not markedly elevated in our patients, which could be due to a good euvolemic status. We conclude that different methods for fluid status evaluation are complementary, with lung ultrasound as a beneficial tool in routine clinical practice in peritoneal dialysis patients.

Central venous pressure estimation from ultrasound assessment of the jugular venous pulse.

ObjectivesAcquiring central venous pressure (CVP), an important clinical parameter, requires an invasive procedure, which poses risk to patients. The aim of the study was to develop a non-invasive methodology for determining mean-CVP from ultrasound assessment of the jugular venous pulse.MethodsIn thirty-four adult patients (age = 60 ± 12 years; 10 males), CVP was measured using a central venous catheter, with internal jugular vein (IJV) cross-sectional area (CSA) variation along the cardiac beat acquired using ultrasound. The resultant CVP and IJV-CSA signals were synchronized with electrocardiogram (ECG) signals acquired from the patients. Autocorrelation signals were derived from the IJV-CSA signals using algorithms in R (open-source statistical software). The correlation r-values for successive lag intervals were extracted and used to build a linear regression model in which mean-CVP was the response variable and the lagging autocorrelation r-values and mean IJV-CSA, were the predictor variables. The optimum model was identified using the minimum AIC value and validated using 10-fold cross-validation.ResultsWhile the CVP and IJV-CSA signals were poorly correlated (mean r = -0.018, SD = 0.357) due to the IJV-CSA signal lagging behind the CVP signal, their autocorrelation counterparts were highly positively correlated (mean r = 0.725, SD = 0.215). Using the lagging autocorrelation r-values as predictors, mean-CVP was predicted with reasonable accuracy (r2 = 0.612), with a mean-absolute-error of 1.455 cmH2O, which rose to 2.436 cmH2O when cross-validation was performed.ConclusionsMean-CVP can be estimated non-invasively by using the lagged autocorrelation r-values of the IJV-CSA signal. This new methodology may have considerable potential as a clinical monitoring and diagnostic tool.

A preoperative estimate of central venous pressure is associated with early Fontan failure

ObjectiveEarly Fontan failure is a serious complication after total cavopulmonary connection, characterized by high central venous pressure, low cardiac output, and resistance to medical therapy. This study aimed to estimate postoperative central venous pressure in patients with total cavopulmonary connection using data routinely collected during preoperative assessment. We sought to determine if this metric correlated with measured postoperative central venous pressure and if it was associated with early Fontan failure. MethodsIn this retrospective study, central venous pressure in total cavopulmonary connection was estimated in 131 patients undergoing pre–total cavopulmonary connection assessment by cardiac magnetic resonance imaging and central venous pressure measurement under general anesthesia. Postoperative central venous pressure during the first 24 hours in the intensive care unit was collected from electronic patient records in a subset of patients. Early Fontan failure was defined as death, transplantation, total cavopulmonary connection takedown, or emergency fenestration within the first 30 days. ResultsEstimated central venous pressure in total cavopulmonary connection correlated significantly with central venous pressure during the first 24 hours in the intensive care unit (r = 0.26, P = .03), particularly in patients without a fenestration (r = 0.45, P = .01). Central venous pressure in total cavopulmonary connection was significantly associated with early Fontan failure (odds ratio, 1.1; 95% confidence interval, 1.01-1.21; P = .03). A threshold of central venous pressure in total cavopulmonary connection 33 mm Hg or greater was found to have the highest specificity (90%) and sensitivity (58%) for identifying early Fontan failure (area under receiver operating curve = 0.73; odds ratio, 12.4; 95% confidence interval, 2.5-62.3; P = .002). This association was stronger in patients with single superior vena cava. ConclusionsEstimated central venous pressure in total cavopulmonary connection is an easily calculated metric combining preoperative pressure and flow data. Higher central venous pressure in total cavopulmonary connection is associated with an increased risk of early Fontan failure and is correlated with directly measured post–total cavopulmonary connection pressure. Identification of patients at risk of early Fontan failure has the potential to guide risk-mitigation strategies.

1633 Final non-invasive echo-guided assessment of left atrial pressure after percutaneous edge-to-edge procedure for mitral regurgitation

Abstract Background/Introduction. Recently the central role of hemodynamic invasive monitoring during MitraClip (Abbott Vascular, Santa Clara, CA, USA) procedure has been raised. After removal of Steerable Guide Catheter (SGC) at the end of procedure, iatrogenic interatrial septum defect determines acute sub-clinical hemodynamic changes depending on right atrial (RA) and left atrial (LA) pressures. The possibility to assess LAP non-invasively by Doppler -echocardiography at the end of the procedure allows to quantify real hemodynamic impact of reduction of MR and leaves the door open to further therapeutic decisions (such as closure of iatrogenic IASd). Purpose This prospective study aimed to assess the role of evaluation of post-procedural mean trans-atrial gradient with continuous-wave (CW) Doppler (DPmean-IAS) in estimating final m-LAP after removal of SGC. Methods We prospectively performed the computation of trans-atrial CW- Doppler tracing for estimation of mean-transatrial gradient (meanGp-LA-RA) in patients treated with MitraClip; we added the estimation of central venous pressure (CVP) according to: i) dilatation of superior vena cava (IVC, mm); ii) presence or not of systolic excursion of IVC (end-inspiratory excursion was not evaluable in patients under sedation); iii) hepatic vein dilatation. The sum of CVP estimated and meanGp-LA-RA (mmHg) represents the m-LAP-Echo-measured at the end of procedure. This value has been compared with m-LAP measured invasively before removal of SGC. We tested the inter-rater reliability with the Intra-class Correlation Coefficient for comparing this method with the gold standard (invasive assessment of LAP). Results we included 19 patients; aetiology of MR was degenerative in 89% of cases. Basal m-LAP was 15 ± 13,3 mmHg and decreased by 32% by the end of procedure (mean-LAP at the end: 10,1 ± 3,3 mmHg, p &amp;lt; 0.001). At the end of the procedure mean Gp-LA-RA was 2.5 ± 1.2 mmHg and CVP 7.5 ± 3.5; the m-LAP-Echo-measured was 9.6 ± 2.4. The delay in time of computation of m-LAP by echocardiography with respect to last invasive assessment available was computed and settled around 5 minutes (IQR 3-9 min). The inter-rater reliability with the Intra-class Correlation Coefficient was high: 0.8, (CI95% 0.647-0.948, p &amp;lt; 0.01); with Bland-Altman test we could assess that bias of measures was acceptable for this clinical context with upper concordance limit of 2,7 mmHg and lower of 4,7 mmHg, with a bias of 0,9 mmHg, not relevant for this clinical purpose. Conclusions The present study represents the first validation of a Doppler-based method for non invasively assessing post-procedural LAP in percutaneous mitral valve interventions requiring transeptal approach. Follow up is needed for correlate this value with clinical outcomes.

Estimation of Central Venous Pressure by Pacemaker Lead Impedances in Left Ventricular Assist Device Patients.

Volume status assessment in left ventricular assist device (LVAD) patients remains challenging. Cardiac resynchronization therapy (CRT) devices are common in LVAD patients, and the impedance across the CRT leads may be associated with hemodynamics and serve as a tool for noninvasive estimation of volume status. Ninety-one sets of measurements including cardiac filling pressures and lead impedances were prospectively obtained during ramp tests from 11 LVAD patients (65.5 ± 9.7 years old; nine male) with CRT devices. Right atrial (RA), right ventricular (RV), and left ventricular (LV) lead impedances were all significantly associated with central venous pressure (CVP) (p < 0.05). We derived the following equation: estimated CVP = 47.90-(0.086 × RA lead impedance) + (0.013 × RV lead impedance)-(0.020 × LV lead impedance). The estimated CVP had a significant correlation (r = 0.795) and good agreement with the measured CVP (mean difference -0.14 ± 1.77 mmHg). Applying the above equation on the validation cohort of twenty-one patients also maintained a strong association with measured CVP (r = 0.705). In conclusion, we have derived a novel equation to estimate CVP using lead impedance measurements. This finding may allow noninvasive monitoring of volume status in LVAD patients.

Unusual Termination of the Facial Vein into External Jugular Vein and its Clinical Implication

The superficial veins of the neck are used for cannulation, either for intravenous infusion or for central venous pressure monitoring. Variations in the venous system from the normal pattern are relatively common. We present some unusual variations of the facial vein draining into the external jugular vein instead of draining into the internal jugular vein. The external jugular vein usually begins just behind the angle of the mandible by the union of the posterior auricular vein with the posterior division of the retromandibular vein and then descends obliquely across the sternocleidomastoid muscle and, just above the clavicle, pierces the deep fascia and drains into the subclavian vein. External jugular vein gives a reliable estimate of central venous pressure. The variation may give false value of pressure due to facial vein draining into it, also may create difficulty in catheterization. It’s very important not only for anatomists but also for head and neck surgeons to be aware of the possible anatomical variation in the formation of external jugular Vein and its clinical implications.

Comparison between femoral vein diameter and inferior vena cava diameter by ultrasound in estimation of central venous pressure in mechanically ventilated patients

Background Bedside ultrasonography is used as a noninvasive method for hemodynamic monitoring, evaluation of inferior vena cava (IVC) diameter by sonography provides an alternative tool for evaluation of intravascular volume. Femoral vein is a superficial compliant vessel, and images can be easily obtained. A significant correlation between central venous pressure (CVP) and common iliac vein pressure was reported previously, meaning that the femoral vein could be a noninvasive alternative to the CVP. Patients and methods We enrolled 100 adult patients in this study. During measurement, the patient was in supine position. The CVP was uniformly measured at the end of expiration, with the pressure transducer having been zeroed at the level of mid axillary line. IVC image was obtained using General Electric ultrasound machine and 3.5-MHz convex probe. The transducer is placed in a vertical plane in the subxiphoid view. The intrahepatic portion of the IVC was visualized as it entered the right atrium. Approximately 3–4 cm from the junction of the IVC and right atrium, the IVC diameter was obtained. Using M mode, the maximum and minimum diameter during inspiration and expiration diameter were recorded, respectively. To get the femoral vein diameter (FVD), we scanned the femoral triangle starting at the inguinal crease using a linear array transducer (5–10 MHz). FVD was measured just caudal to the saphenofemoral junction. Results We enrolled 100 patients in this study. Their mean age was 56 years, mean CVP was 6 cm H2O, mean IVC diameter during inspiration was 15 cm, whereas during expiration was 13.6 cm, and the FVD was 8.2 cm. There were significant correlations between both CVP and IVC diameter (insp and exp) and FVD. CVP correlation with FVD was 0.59, IVC diameter during inspiration with FVD was 0.41, and IVC diameter during expiration with FVD was 0.42. Conclusion FVD can be used as a noninvasive alternative method to assess intravascular volume status.

IJV collapsibility index vs IVC collapsibility index by point of care ultrasound for estimation of CVP: a comparative study with direct estimation of CVP.

PurposeTo compare the bedside ultrasound estimation of internal jugular vein (IJV)-collapsibility index with inferior vena cava (IVC)-collapsibility index and invasively monitored central venous pressure (CVP) in ICU patients.Designprospective observational study.SettingThe study was carried out in the ICU of Al Wakra and Al Khor hospitals of the Hamad Medical Corporation, Qatar. The patients were enrolled from November 2013 to January 2015.PatientsPatients admitted to the ICU with central venous catheter were included.Material and methodsThe A-P diameter, cross-sectional area of the right IJV, and diameter of IVC were measured using bedside USG, and their corresponding collapsibility indices were obtained. The results of the IJV and IVC indices were compared with CVP. The sensitivity, specificity, and positive and negative predictive values were calculated to determine the diagnostic and predictive accuracy of the IJV collapsibility index in predicting the CVP.ResultsSeventy patients were enrolled, out of which 12 were excluded. The mean age was 54.34±16.61 years. The mean CVP was 9.88 mmHg (range =1–25). The correlations between CVP and IJV-CI (collapsibility index) at 0° were r=−0.484 (P=0.0001), r=−0.416 (P=0.001) for the cross-sectional area (CSA) and the diameter, respectively, and, at 30°, the most significant correlation discovered was (r=−0.583, P=0.0001) for the CSA-CI and r=−0.559 (P=0.0001) for the diameter-CI. In addition, there was a significant and negative correlation between IVC-CI and CVP (r=−0.540, P=0.0001).ConclusionThe IJV collapsibility index, especially at 30° head end elevation, can be used as a first-line approach for the bedside non-invasive assessment of CVP/fluid status in critical patients. IVC-CI can be used either as an adjunct or in conditions where IJV assessment is not possible, such as in the case of a neck trauma/surgery.

Three-Dimensional inferior vena cava for assessing central venous pressure in patients with cardiogenic shock

Evaluation of central venous pressure (CVP) by inferior vena cava (IVC) measurements is crucial in the management of patients with cardiogenic shock to optimize drugs therapy. IVC has a complex 3-dimensional (3D) shape but measurements used to estimate CVP remain based on 2-dimensional (2D) echocardiographic imaging. The aim of this study was to investigate the accuracy of CVP estimation by IVC size and collapsibility index obtained using 3D-echocardiography compared with 2D in patients with cardiogenic shock. Eighty consecutive echocardiographic examinations performed in 33 patients (72 ± 15 years, left ventricular ejection fraction = 19 ± 10%) admitted for cardiogenic shock were prospectively included. Two and three-dimensional images of the IVC, performed at baseline and when CVP was ≤ 10 mmHg, were acquired simultaneous with invasive measurement of CVP, both at rest and during sniff test. 2D and 3D IVC diameters, 3D IVC area and collapsibility index (IVCCI) were assessed. The eccentricity index (EI) was computed from 3D data as the ratio of maximum over minimum IVC diameter. The cut-off value of 10 mmHg of CVP defined patient with euvolemia hemodynamic status. At rest, the IVC diameter averaged 23 ± 7 mm by 2D and 25 ± 8 × 19 ± 7 mm by 3D. IVC had an eccentric shape (EI = 1.3) that increased when CVP was ≤10 mmHg and during sniff test ( P < 0.001). IVC measurements by 2D and 3D were correlated with CVP. The best correlation was obtained with IVCCI derived from 2D diameters (R = -0.69) and 3D areas (R = −0.82). Using the cutoff value of 50% for IVCCI, a discrepancy between invasive CVP measurements and IVCCI has been observed for 11 examinations (13%) by 2D but only one was misclassified by 3D. Inter and intra-observer reproducibility for IVC area was 7 ± 6% and 5 ± 3%, respectively ( Fig. 1 ). In patients with cardiogenic shock, IVCCI from area by 3D echocardiography is reproducible and accurate to evaluate CVP.