Internal jugular vein/common carotid artery cross-sectional area ratio and central venous pressure

A Novel Spectral Index for Tracking Preload Change from a Wireless, Wearable Doppler Ultrasound

A wireless, wearable Doppler ultrasound offers a new paradigm for linking physiology to resuscitation medicine. To this end, the image analysis of simultaneously-acquired venous and arterial Doppler spectrograms attained by wearable ultrasound represents a new source of hemodynamic data. Previous investigators have reported a direct relationship between the central venous pressure (CVP) and the ratio of the internal jugular-to-common carotid artery diameters. Because Doppler power is directly related to the number of red cell scatterers within a vessel, we hypothesized that (1) the ratio of internal jugular-to-carotid artery Doppler power (V/A_POWER) would be a surrogate for the ratio of the vascular areas of these two vessels and (2) the V/A_POWER would track the anticipated CVP change during simulated hemorrhage and resuscitation. To illustrate this proof-of-principle, we compared the change in V/A_POWER obtained via a wireless, wearable Doppler ultrasound to B-mode ultrasound images during a head-down tilt. Additionally, we elucidated the change in the V/A_POWER during simulated hemorrhage and transfusion via lower body negative pressure (LBNP) and release. With these Interesting Images, we show that the Doppler V/A_POWER ratio qualitatively tracks anticipated changes in CVP (e.g., cardiac preload) which is promising for both diagnosis and management of hemodynamic unrest.

The effect of gravity-induced preload change on the venous excess ultrasound (VExUS) score and internal jugular vein Doppler in healthy volunteers

BACKGROUND

The venous excess ultrasound (VExUS) score is a multi-organ Doppler approach to assess venous congestion. Despite growing use of VExUS in research and clinical practice, other veins can be visualized to assess for venous hypertension, which may overcome acquisition barriers of the VExUS exam. In this pilot, observational study, we used a wearable Doppler ultrasound to assess the relationship between jugular venous Doppler and the VExUS score under different preload conditions. We hypothesized that jugular Doppler morphology would accurately distinguish preload conditions, that it would most closely relate to the hepatic venous Doppler morphology in the fully supine position and that the VExUS score would be influenced by preload condition.

RESULTS

We recruited 15 healthy volunteers with no cardiovascular history. Preload change was achieved using a tilt-table with three positions: supine, fully upright, and 30-degree head-down tilt. In each position, a VExUS score was performed; furthermore, inferior vena collapsibility and sphericity index were calculated. At the same time, jugular venous Doppler was captured by a novel, wireless, wearable ultrasound system. A continuous jugular venous Doppler morphology was 96% accurate for detecting the low preload condition. The jugular venous Doppler morphology was highly correlated with the hepatic vein, but only in the supine position. Gravitational position did not significantly affect the sphericity index or the VExUS score.

CONCLUSIONS

The jugular vein Doppler morphology was able to accurately distinguish low from high preload conditions in healthy volunteers. Comparisons between VExUS Doppler morphologies and other veins should occur in the supine position when gravitational pressure gradients are minimized; finally, different preload conditions in healthy subjects did not affect the VExUS score.

Correlation of internal jugular vein, common carotid artery, femoral artery and femoral vein diameters with central venous pressure

BACKGROUND

This study aimed to detect the correlation of central venous pressure (CVP) with the internal jugular vein (IJV), common carotid artery (CCA), femoral vein (FV), and femoral artery (FA) diameters measured with ultrasound (USG) in patients under mechanical ventilation to evaluate whether they are suitable to be used as an alternative low-cost and noninvasive method for the detection of CVP.

METHODS

A total of 40 patients aged from 18 to 90 who had been receiving therapy in the intensive care unit (ICU) were included in the study. Central venous catheter was placed into the patients through right IJV or subclavian vein in their first 24-hour of hospitalization and the right atrium pressure (RAP) was measured from the catheter, the tip of which was confirmed to reach right atrium. In the same session, CCA, IJV, FA, and FV diameters were measured with USG and their correlations with CVP were calculated. In addition, correlations of the measured venous and artery diameters between each other were detected as well.

RESULTS

There was a significantly high correlation between CVP and CCA diameter (R = 0.603, P < .000). There was a significantly low correlation between CVP and IJV diameter (R = 0.352, P = .026), a significantly low correlation between FA and FV diameters (R = 0.317, P = .047), a significantly low correlation between FA and CCA diameters (R = 0.330, P = .038), and a significantly low correlation between IJV and CCA diameters (R = 0.364, P = .020).

CONCLUSION

CVP and CCA diameters exhibited a high correlation. For detection of CVP, the ultrasonographic CCA diameter measurement can be used as an alternative noninvasive method which is easy to use and minimally affected by measurement errors of individuals and which has low learning curve compared with the other measurement methods.

Internal jugular vein ultrasound for the diagnosis of hypovolemia and hypervolemia in acutely ill adults: a systematic review and meta-analysis

Accurate volume status assessments allow physicians to rapidly implement therapeutic measures in acutely unwell patients. However, existing bedside diagnostic tools are often unreliable for assessing intravascular volume. We searched PUBMED, EMBASE, CENTRAL, and Web of Science for English language articles without date restrictions on January 20, 2022. Studies reporting the diagnostic accuracy of IJV-US for hypovolemia and/or hypervolemia in an acute care setting were screened for inclusion. We included studies using any method of IJV-US assessment as the index test, compared against any reference standard. We fitted hierarchical summary receiver operating characteristic (HSROC) models for meta-analysis of diagnostic test accuracy, separately for hypovolemia and hypervolemia. Two reviewers independently extracted data and assessed risk of bias using QUADAS-2. We assessed certainty of evidence using the GRADE approach. A total of 26 studies were included, of which 19 studies (956 patients) examined IJV-US for hypovolemia and 13 studies (672 patients) examined IJV-US for hypervolemia. For the diagnosis of hypovolemia, IJV-US had a pooled sensitivity of 0.82 (95% CI 0.76 to 0.87; moderate-certainty evidence) and specificity of 0.82 (95% CI 0.73 to 0.88; moderate-certainty evidence). Measurement of IJV collapsibility indices had higher diagnostic accuracy (sensitivity 0.85, 95% CI 0.80 to 0.89; specificity 0.78, 95% CI 0.64 to 0.88) than static IJV indices (sensitivity 0.73, 95% CI 0.60 to 0.82; specificity 0.70, 95% CI 0.48 to 0.86). For the diagnosis of hypervolemia, IJV-US had a pooled sensitivity of 0.84 (95% CI 0.70 to 0.92; moderate-certainty evidence) and specificity of 0.70 (95% CI 0.55 to 0.82; very low-certainty evidence). IJV-US has moderate sensitivity and specificity for the diagnosis of hypervolemia and hypovolemia. Randomized controlled trials are needed to determine the role of IJV-US for guiding therapeutic interventions aimed at optimizing volume status.

Bedside ultrasound to assess acute central venous pressure change during treatment of decompensated heart failure

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Volume status assessment by physical exam in heart failure patients is often inaccurate.

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Right heart catheterization (RHC) carries safety, pragmatic and financial burdens.

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A non-invasive, safe, and reliable alternative for accurate assessment of volume status is needed for optimal management of heart failure.

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Serial portable ultrasonic assessment of internal jugular vein compliance can act as a surrogate for RHC to determine volume status.

Background

Accurate volume status assessment is crucial for the treatment of acute decompensated heart failure (ADHF). Volume status assessment by physical exam is often inaccurate, necessitating invasive measurement with right heart catheterization (RHC), which carries safety, pragmatic (scheduling, holding anticoagulants, etc.), and financial burdens. Therefore, a reliable, non-invasive, cost-effective alternative is desired. Previously, we developed an ultrasound (US) based technique to measure internal jugular vein (IJV) compliance during RHC which was used for single time point central venous pressure (CVP) predictions. We now aim to apply this technique to track acute changes in CVP during diuresis for ADHF in patients with an in-dwelling pulmonary artery catheter (PAC).

Methods

We used an observational, prospective study design and recruited 15 patients from the cardiac critical unit (CCU) being treated for ADHF (systolic or diastolic) with intravenous (IV) diuretics with/without inotropic agents who underwent Swan- Ganz catheter/PAC insertion for continuous CVP monitoring. 13 of 15 patients received milrinone infusions. US images of the IJV were obtained at end-expiration and during the strain phase of Valsalva at multiple 2–3 hours intervals. Change in IJV cross-sectional area (CSA) (ImageJ) was used as a measure of IJV compliance. Patients unable to perform the Valsalva maneuver were excluded.

Results

Calculated percentage change (%Δ) in CSA of IJV was plotted against CVP. An inverse relationship was observed between CVP and %Δ in CSA of IJV. The data was fit with a polynomial regression curve (R² = 0.36, root mean square error = 3.19). Fivefold cross-validation showed a stable model for predicting CVP based on CSA (R² = 0.31, root mean square error = 3.18)

Conclusion

Serial portable US assessment of IJV compliance can act as a surrogate measure of CVP and, therefore, can provide reliable information on acute hemodynamic changes in ADHF.

Venous cannula occlusion during cardiopulmonary bypass recognized by ultrasonography of the internal jugular vein

Background

Occlusion or malposition of the venous cannula during cardiopulmonary bypass (CPB) increases central venous pressure (CVP). When high CVP is measured, we need to determine if it is actually high or if it is measured due to catheter occlusion or technical problems with the measurement.

Case presentation

We experienced a case of excessively high CVP due to malposition of the venous cannula during CPB. A 78-year-old woman underwent an aortic arch replacement for acute aortic dissection. During CPB, CVP increased up to 78 mmHg, and the time above 50 mmHg was 48 min. In this case, ultrasonography of the internal jugular vein (IJV) was useful to confirm high CVP.

Conclusions

Ultrasonography is now a familiar diagnostic tool and can be used at any time. We should consider ultrasonography as the first choice for diagnosing the cause of high CVP during CPB.

Sonographic Assessment of the Effects of Mechanical Ventilation on Carotid Flow Time and Volume

Background

Corrected carotid flow time (CFTc) and carotid blood flow (CBF) are sonographic measurements used to assess fluid responsiveness in hypotension. We investigated the impacts of mechanical ventilation on CFTc and CBF.

Materials and methods

Normotensive patients undergoing cardiac surgery were prospectively enrolled. Carotid ultrasound (US) was performed pre and post-intubation. Post-intubation measurements took place after the initiation of mechanical ventilation. To measure CFTc and CBF, a sagittal carotid view was obtained with pulse wave-Doppler (maximum angle 60°). CFTc was calculated with the Bazett formula (CFTc = systolic time/√cycle time). CBF was calculated using CBF (mL/min) = area (cm ² ) x time average mean velocity (TAMEAN) (cm/sec) x 60 (sec/min). The maximum carotid diameter was measured at the level of the thyroid.

Results

Twenty patients were enrolled. Mean CFTc pre-intubation was 328 ms (SD 43.9 ms) compared to CFTc post-intubation 336 ms (SD 36 ms). There was no significant difference between pre and post-intubation CFTc (mean differences=-0.008; t(19)=-0.71, p=.49). Mean CBF pre-intubation was 487 mL/min (SD 176 mL/min) compared to CBF post-intubation 447 mL/min (SD 187 mL/min). There was no significant difference between pre and post-intubation CBF (mean differences= 40; t(19)=1.24, p=.23).

Conclusions

In this study of normotensive patients, there were no detected differences in CFTc or CBF pre and post-intubation with mechanical ventilation.

Diagnostic accuracy of internal jugular vein ultrasound in quantification of the central venous pressure for hemodialysis patients

Background

Assessment of the central venous pressure (CVP) is an essential hemodynamic parameter for monitoring the dialyzing patients. Our objective of the present study is to investigate the accuracy of CVP measurement by internal jugular vein US in comparison to the direct measurement by the central venous catheters for hemodialysis patients. We included 106 patients; where their CVP was assessed in two different non invasive US methods (CVPni) separately and in combination and the obtained measurements were correlated to the invasive measurements (CVPi) by catheters.

Results

By method 1, there is a highly significant positive correlation between CVPni and CVPi (ρ < 0.001) and a Pearson correlation coefficient (r = 0.913 n = 93), and by method 2, there is also a highly significant positive correlation between the CVPni and CVPi in both groups (r = 0.832, 95%, n = 106, p < 0.001), 1.935 was the cut-off point for prediction of CVP ≥ 10cmH20. For differentiation between patients with CVP < 10cmH20 and ≥ 10cmH20, the accuracy measures (sensitivity, specificity, PPV, NPV, and overall accuracy) were 100%, 79.31%, 74.47%, 100%, and 87.10% by method 1, and were 91.11%, 85.48%, 82.00%, 92.98%, and 87.85% by method 2, while the combination of both methods had gained 88.57%, 89.66%, 83.78%, 92.86%, and 89.25%, respectively.

Conclusion

The US offered a reliable and non-invasive tool for monitoring CVP. The present study has a novelty of combining more than one US method and this had reported higher accuracy measures and outperformed the use of a single method.

Non-invasive Assessment of Intravascular Volume Status for Postoperative Patients: The Correlation Between the Internal Jugular Vein/Common Carotid Artery Cross-sectional Area Ratio and the Inferior Vena Cava Diameter

Background

This study aimed to assess the correlation between the internal jugular vein/common carotid artery (IJV/CCA) cross-sectional area (CSA) ratio and the inferior vena cava (IVC) diameter as non-invasive techniques for the assessment of intravascular volume.

Methods

The study samples included 35 adult patients of both sexes (age range: 20 - 60 years) according to the criteria of the American Society of Anaesthesiology (ASA) physical status II - III, who were admitted to the surgical intensive care unit (SICU) after major surgeries for the assessment of intravascular volume status.

Results

There was a positive correlation between the IJV/CCA CSA ratio and the IVC maximum and minimum diameter before and after fluid infusion (r = 0.923, P < 0.001 and r = 0.390, P = 0.021, respectively) and between the IJV/CCA CSA ratio at inspiration and the IVC minimum diameter before and after fluid infusion (r = 0.605, P < 0.001 and r = 0.496, P < 0.001, respectively). The sensitivity and specificity analysis of the IJV/CCA CSA during inspiration after fluid correction to predict a central venous pressure (CVP) of 8 - 12 cmH₂O showed that at a ratio of 2.56, the highest sensitivity was 56.5%, and the specificity was 83.3%; at a ratio of 2.58, the highest sensitivity was 65.2% and the specificity was 75%. During expiration, at a ratio of 2.62, the highest sensitivity was 52.2%, and the specificity was 67%; and at a ratio of 2.65, the sensitivity was 56.5%, and the specificity was 50%.

Conclusions

The assessment of the IJV/CCA CSA ratio using bedside ultrasound could be a non-invasive tool for the evaluation of intravascular volume status in spontaneously breathing adult patients after major surgeries.

Spectral characteristics of the internal jugular vein and central venous pressure pulses: a proof of concept study

In this proof-of-concept study the impact of central venous pressure (CVP) on internal jugular veins cross-sectional area (CSA) and blood flow time-average velocity (TAV) was evaluated in eight subjects, with the aim of understanding the drivers of the jugular venous pulse. CVP was measured using a central venous catheter while CSA variation and TAV along a cardiac cycle were acquired using ultrasound. Analysis of CVP, CSA and TAV time-series signals revealed TAV and CSA to lag behind CVP by on average 0.129 s and 0.138 s, with an inverse correlation between CSA and TAV (r= –0.316). The respective autocorrelation signals were strongly correlated (mean r=0.729-0.764), with mean CSA periodicity being 1.062 Hz. Fourier analysis revealed the frequency spectrums of CVP, TAV and CSA signals to be dominated by frequencies at approximately 1 and 2 Hz, with those >1 Hz greatly attenuated in the CSA signal. Because the autocorrelograms and periodograms of the respective signals were aligned and dominated by the same underlying frequencies, this suggested that they are more easily interpreted in the frequency domain rather than the time domain.

Reducing intracranial pressure by reducing central venous pressure: assessment of potential countermeasures to spaceflight-associated neuro-ocular syndrome

Spaceflight-associated neuro-ocular syndrome (SANS) involves unilateral or bilateral optic disc edema, widening of the optic nerve sheath, and posterior globe flattening. Owing to posterior globe flattening, it is hypothesized that microgravity causes a disproportionate change in intracranial pressure (ICP) relative to intraocular pressure. Countermeasures capable of reducing ICP include thigh cuffs and breathing against inspiratory resistance. Owing to the coupling of central venous pressure (CVP) and intracranial pressure, we hypothesized that both ICP and CVP will be reduced during both countermeasures. In four male participants (32 ± 13 yr) who were previously implanted with Ommaya reservoirs for treatment of unrelated clinical conditions, ICP was measured invasively through these ports. Subjects were healthy at the time of testing. CVP was measured invasively by a peripherally inserted central catheter. Participants breathed through an impedance threshold device (ITD, -7 cmH₂O) to generate negative intrathoracic pressure for 5 min, and subsequently, wore bilateral thigh cuffs inflated to 30 mmHg for 2 min. Breathing through an ITD reduced both CVP (6 ± 2 vs. 3 ± 1 mmHg; P = 0.02) and ICP (16 ± 3 vs. 12 ± 1 mmHg; P = 0.04) compared to baseline, a result that was not observed during the free breathing condition (CVP, 6 ± 2 vs. 6 ± 2 mmHg, P = 0.87; ICP, 15 ± 3 vs. 15 ± 4 mmHg, P = 0.68). Inflation of the thigh cuffs to 30 mmHg caused no meaningful reduction in CVP in all four individuals (5 ± 4 vs. 5 ± 4 mmHg; P = 0.1), coincident with minimal reduction in ICP (15 ± 3 vs. 14 ± 4 mmHg; P = 0.13). The application of inspiratory resistance breathing resulted in reductions in both ICP and CVP, likely due to intrathoracic unloading.NEW & NOTEWORTHY Spaceflight causes pathological changes in the eye that may be due to the absence of gravitational unloading of intracranial pressure (ICP) under microgravity conditions commonly referred to as spaceflight-associated neuro-ocular syndrome (SANS), whereby countermeasures aimed at lowering ICP are necessary. These data show that impedance threshold breathing acutely reduces ICP via a reduction in central venous pressure (CVP). Whereas, acute thigh cuff inflation, a popular known spaceflight-associated countermeasure, had little effect on ICP and CVP.

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

Objectives

Acquiring 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.

Methods

In 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.

Results

While 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.

Conclusions

Mean-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.

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

Purpose

To 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.

Design

prospective observational study.

Setting

The 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.

Patients

Patients admitted to the ICU with central venous catheter were included.

Material and methods

The 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.

Results

Seventy 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).

Conclusion

The 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.

Lund exhaust on hemodynamic parameters and inflammatory mediators in patients undergoing cardiac valve replacement under cardiopulmonary bypass

The effect of Lund exhaust technique on hemodynamics and inflammatory mediators in patients undergoing cardiac valve replacement under cardiopulmonary bypass was evaluated. A total of 60 patients with heart disease undergoing elective heart valve replacement under elective cardiopulmonary bypass were randomly divided into Lund exhaust group (group A) and control group (group B), with 30 patients in each group. Group A underwent Lund exhaust during cardiopulmonary bypass, while group B was identical to group A except for not using the Lund exhaust technique during cardiopulmonary bypass. The hemodynamic parameters at different time-points showed that the indexes of MAP, PASP, CO, CI, PCWP, CVP and SVR in T₁, T₂, T₃ and T₄ moments between group A and group B were statistically significant (p<0.05). There was no statistical significance in IL-6, IL-8, IL-10, TNF-α and TIMP-1 between group A and group B patients at the T₀ moment (p>0.05). The levels of IL-6, IL-8, IL-10, TNF-α and TIMP-1 in group B patients at T₁, T₂, T₃ and T₄ moments were statistically significant compared with those in group A (p<0.05). The IL-6, IL-8, TNF-α indexes of group B patients were statistically significant at the T₅ moment compared with those in group A (p<0.05). The IL-10 and TIMP-1 of two groups were not statistically significant at the T₅ moment. The operating time, CPB time, aortic clamp time, intraoperative blood loss, postoperative tube time, ICU stay time, hospital stay time and pulmonary infection of patients in group A were significantly less than those in group B. In conclusion, Lund exhaust technology can significantly reduce the fluctuation of hemodynamics, decrease the expression of inflammatory factors, improve lung function, and is conducive to the rehabilitation of patients.

Ultrasonographic assessment of the internal jugular vein for the estimation of central venous pressure in hemodialysis patients: A preliminary study

PURPOSE

To investigate a new noninvasive method to assess central venous pressure (CVP) in hemodialysis patients, based on the ultrasonographic measurement of the collapsing point of the internal jugular vein (CVPni).

MATERIALS AND METHODS

In this preliminary, noninterventional, single center study, we enrolled 22 dialyzed patients with an indwelling jugular catheter. CVPni was compared to the gold-standard invasive measurement of CVP using the central venous catheter (CVPi). Agreement between CVPi and CVPni was assessed by Bland and Altman Method. Correlation was assessed by linear regression.

RESULTS

A strong correlation was observed between CVPi and CVPni (OR = 3.47 [2.96; 4.07], P < .0001). For overloaded patients, the area under the curve for the operating characteristic curve was 0.971 (IC95: 0.915; 1.000). For under-loaded patients, area under the curve was 0.971 (IC95: 0.917; 1.000). The mean bias between intra-individual CVPi and CVPni measures was 0.57 cm H₂ O (SD: 3.1 cm H₂ O).

CONCLUSION

CVPni appears as a noninvasive and reliable technique. Further studies are required to confirm these results and to assess the direct clinical impact of this new method.

Measurement of Internal Jugular Vein and Common Carotid Artery Diameter Ratio by Ultrasound to Estimate Central Venous Pressure

Objective

The objective of this study is to find a correlation between internal jugular vein (IJV) and common carotid artery (CCA) diameter ratio and central venous pressure (CVP) measurement and find a cut-off value for the IJV/CCA ratio to predict low CVP i.e. < 10 cm H₂0, for estimating the volume status in critically ill patients.

Methods

This prospective cross-sectional study was conducted at the critical care department of Shifa International Hospital, Islamabad, from July to December 2017. A sample of 49 patients ≥ 18 years with intrathoracic central venous catheters (CVCs) who underwent bedside sonographic assessments of IJV and CCA diameter were included in this study using convenient sampling. The IJV/CCA diameter ratio was calculated and correlated with CVP and the predictive value of the IJV/CCA diameter ratio to predict CVP < 10 cm H₂O was explored by calculating the area under the receiver operating characteristic (ROC) curve, sensitivity, specificity, and positive and negative predictive values.

Results

A total of 49 patients, 30 males (61.2%) and 19 females (38.8%) with a mean age of 56.00±16.11 years were included in the study. The mean CVP was 8.98±2.37cm H₂O in ventilated (51%) and 10.7± 6.01 cm H₂O in non-ventilated (49%) patients. The mean IJV/CCA diameter ratio was 1.60±0.55 at expiration and 1.41±0.56 at inspiration. There was a significant correlation between the IJV/CCA diameter ratio and CVP at expiration (r=0.401, p=0.004). The correlation between IJV/CCA and CVP was significant in non-ventilated patients at expiration (r=0.439, p=0.032). The area under the ROC curve for the IJV/CCA diameter ratio for predicting CVP < 10 cm H₂O was 0.684 (p=0.028). The predictive value of the IJV/CCA diameter ratio for CVP < 10 cm H₂0 at the cutoff value of < 2 was insignificant. A new cut-off < 1.75 was taken for the IJV/CCA diameter ratio from the coordinates of the ROC curve. The sensitivity, specificity, PPV, and NPV of an IJV/CCA diameter ratio of < 1.75 for predicting a CVP < 10 cm H₂0 were 84.62%, 52.17%, 66.67%, and 75.00%, respectively.

Conclusion

The assessment of volume status by the IJV/CCA diameter ratio with a sonographic device may be a useful noninvasive alternative for a central venous catheterization with a cut-off < 1.75.

Anatomic variations of neck vessels and the course of pediatric internal jugular veins

BACKGROUND

Landmark-guided internal jugular vein cannulation is difficult for pediatric patients but useful, especially when ultrasound equipment is unavailable. Therefore, it is important to define the adjacent anatomic characteristics of the pediatric internal jugular vein.

METHODS

In 210 children the course of the internal jugular vein, and common carotid and vertebral arteries was measured from the level of the cricoid cartilage to the supraclavicular area using ultrasound.

RESULTS

From the level of the cricoid cartilage to the supraclavicular area, vessel diameter increased with internal jugular vein increasing by 12%, and common carotid and vertebral arteries increasing by 5% each. From the level of the cricoid cartilage to the supraclavicular area, the number of patients with a medial common carotid artery position relative to the internal jugular vein increased, whereas those with a lateral position decreased; the number of patients with nonoverlapped common carotid artery-internal jugular vein increased, and those with totally overlapped decreased. In contrast, the overlapping status of vertebral artery-internal jugular vein changes oppositely. More than 97.14% of the vertebral artery lies lateral to the internal jugular vein at these levels. The minimal vertebral artery-internal jugular vein depth decreased from 0.46±0.20 to 0.37±0.19 cm. The angle from the internal jugular vein line to the horizontal line of the body was 83.35±9.04 degrees.

CONCLUSION

The common carotid artery and internal jugular vein are farther apart as one moves down the neck, whereas the vertebral artery and internal jugular vein are getting together. Additionally, the diameter of the internal jugular vein increased.