Central Venous Pressure In Patients Research Articles

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.

Non-invasive Estimation of Right Atrial Pressure Using Inferior Vena Cava Echography

The pulsatility of the inferior vena cava (IVC) reflects the volume status and central venous pressure of patients. The standard clinical indicator of IVC pulsatility is the caval index (CI), measured from ultrasound recordings. However, its estimation is not standardized and is vulnerable to artifacts, mostly because of IVC movements during respiration. Thus, we used a (recently patented) semi-automated method that tracks IVC movements and averages the CI across an entire section of the vein, which provides a more stable indication of pulsatility. This algorithm was used to estimate the CI, pulsatility indicators reflecting either respiratory or cardiac stimulation and the mean diameter of the IVC. These IVC indices, together with anthropometric information, were used as potential features to build an innovative model for the estimation of the right atrial pressure (RAP) recorded from 49 catheterized patients. An exhaustive search was carried out for the best among all possible models that could be obtained by using combinations of these features. The model with minimum estimation error (tested with a leave-one-out approach) was selected. This model estimated RAP with an error of about 3.6 ± 2.6 mm Hg (mean ± standard deviation); the error when using only operator measured variables, without software, was about 4.0 ± 2.5 mm Hg. These promising results underline the need for further study of our RAP estimation method on a larger data set.

Effects of SI and PCV on respiratory mechanics, early central drive and hemodynamics in patients with ARDS.

Effects of sustained inflation (SI) and pressure- controlled ventilation (PCV) on respiratory mechanics, early central drive, and hemodynamics in patients with acute respiratory distress syndrome (ARDS) were investigated and compared. A retrospective analysis of 26 patients with ARDS, who were admitted to the Yiwu Central Hospital from March 2015 to March 2016, was performed. According to the ventilation method adopted by the patients with ARDS, 13 patients who received SI treatment were included in the SI group and 13 patients who received PCV treatment were included in the PCV group. The condition of central drive of the patients in the two groups was recorded and calculated continuously before and after recruitment maneuver (RM), the changes of each indicator of the respiratory function and hemodynamics were recorded and calculated before and after RM at 1, 10, 20 and 30 min. The differences were not statistically significant when comparing PIP, Pplate and Crs in patients in the SI group and the PCV group before RM with those after RM at 1, 10, 20 and 30 min (P>0.05), the differences were not statistically significant when comparing heart rate and mean arterial pressure in patients in the SI group and the PCV group before RM with those after RM at 1, 10, 20 and 30 min (P>0.05). Ηowever, central venous pressure in patients in the SI group after RM at 10 and 20 min was significantly higher than that in the PCV group, and the differences were statistically significant (P<0.05). VT/RMS, VE/RMS and ΔPdi/RMS in the SI group and the PCV group after RM were significantly higher than those before RM, and the differences were statistically significant (P<0.05). There was little difference in the effect between SI and PCV on respiratory mechanics, early central drive and hemodynamics in patients with ARDS, and both mechanical ventilation methods enhanced the effect of central-mechanical-ventilation coupling after RM. Therefore, the two mechanical ventilation methods, SI and PCV, were equally available for patients with ARDS.

The Effect of Intravenous Injection of Amiodarone on Central Venous Pressure in Patients Undergoing Coronary Artery Bypass Graft Surgery

The Effect of Intravenous Injection of Amiodarone on Central Venous Pressure in Patients Undergoing Coronary Artery Bypass Graft Surgery

Three-Dimensional Inferior Vena Cava for Assessing Central Venous Pressure in Patients with Cardiogenic Shock

The inferior vena cava (IVC) has a complex three-dimensional (3D) shape, but measurements used to estimate central venous pressure (CVP) remain based on two-dimensional (2D) echocardiographic imaging. The aim of this study was to investigate the accuracy of IVC size and collapsibility index obtained by 3D echocardiography for assessing CVP in patients with cardiogenic shock. Eighty consecutive echocardiographic examinations performed in 33 patients (mean age, 72±15years; mean left ventricular ejection fraction, 19±10%) admitted for cardiogenic shock were prospectively included. Two-dimensional and 3D images of the IVC were acquired simultaneously with invasive measurement of CVP, both at rest and during a sniff test. IVC diameters, 3D IVC area, and IVC collapsibility index (IVCCI) were assessed. The eccentricity index was computed from 3D data as the ratio of maximum to minimum IVC diameter. A cutoff value of 10mm Hg for CVP defined patients with euvolemic hemodynamic status. At rest, IVC diameter averaged 23±7mm by 2D imaging and 25±8×19±7mm by 3D imaging. The IVC had an eccentric shape (eccentricity index=1.3) that increased when CVP was ≤10mm Hg and during the sniff test (P<.001). IVC measurements by 2D and 3D imaging 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 a cutoff value of 50% for IVCCI, 11 examinations were misclassified by 2D imaging and only one by 3D imaging. Inter- and intraobserver reproducibility for IVC area was 7±6% and 5±3%, respectively. In patients with cardiogenic shock, IVCCI from area by 3D echocardiography is reproducible and accurate to evaluate CVP.

Protective effects of recombinant human brain natriuretic peptide in perioperative period during open heart surgery.

The aim of the present study was to evaluate the protective effects and safety aspects of recombinant human brain natriuretic peptide (rhBNP) on cardiac functions of patients undergoing open-heart surgery during perioperative period. In total, 150 patients undergoing open heart surgery in the Second Hospital of Shandong Universty from August 2015 to July 2016 were randomly divided into control group and observation group each with 75 cases. Patients in control group were treated by routine rehabilitation while patients in the observation group were treated by both the routine rehabilitation and rhBNP. All the observations were made before operation, after operation and 7 days after operation. The changes of N-terminal pro-brain natriuretic peptide (NT-proBNP) of patients, the left ventricular ejection fraction (LVEF), cardiac function [Cardiac output (CO), pulmonary capillary wedge pressure (PAWP) and central venous pressure (CVP)] of patients were measured. Further, respirator support time, ICU stay time, incidence of complications and vital signs (BP, HR, SaO2) of patients in the two groups were also compared. NT-proBNP levels of all patients improved after operation but it decreased in both groups after 7 days of operation. The decrease of NT-proBNP levels in observation group was significantly higher than that of control group. Whereas, LVEF, CO, PAWP and CVP of patients in both the groups increased after operation but effects were significantly higher in the observation group after 7 days of medication. Respirator support time and ICU stay time of patients in observation group were significantly shorter than those in control group, and the incidence of postoperative complications of patients in the observation group were significantly lower than the control group. Moreover, BP, HR and SaO2 of patients in observation group were significantly elevated in comparison to control group (P<0.05). Recombinant human brain natriuretic peptide (rhBNP) could significantly improve the cardiac functions of patients after open heart surgery, and is safe as well as reliable.

Effect of Positive End-Expiratory Pressure on Central Venous Pressure in Patients under Mechanical Ventilation.

Finding the probable governing pattern of PEEP and CVP changes is an area of interest for in-charge physicians and researchers. Therefore, the present study was designed with the aim of evaluating the relationship between the mentioned pressures. In this quasi-experimental study, patients under mechanical ventilation were evaluated with the aim of assessing the effect of PEEP change on CVP. Non-trauma patients, over 18 years of age, who were under mechanical ventilation and had stable hemodynamics, with inserted CV line were entered. After gathering demographic data, patients underwent 0, 5, and 10 cmH2O PEEPs and the respective CVPs of the mentioned points were recorded. The relationship of CVP and PEEP in different cut points were measured using SPSS 21.0 statistical software. 60 patients with the mean age of 73.95 ± 11.58 years were evaluated (68.3% male). The most frequent cause of ICU admission was sepsis with 45.0%. 5 cmH2O increase in PEEP led to 2.47 ± 1.53 mean difference in CVP level. If the PEEP baseline is 0 at the time of 5 cmH2O increase, it leads to a higher raise in CVP compared to when the baseline is 5 cmH2O (2.47 ± 1.53 vs. 1.57 ± 1.07; p = 0.039). The relationship between CVP and 5 cmH2O (p = 0.279), and 10 cmH2O (p = 0.292) PEEP changes were not dependent on the baseline level of CVP. The findings of this study revealed the direct relationship between PEEP and CVP. Approximately, a 5 cmH2O increase in PEEP will be associated with about 2.5 cmH2O raise in CVP. When applying a 5 cmH2O PEEP increase, if the baseline PEEP is 0, it leads to a significantly higher raise in CVP compared to when it is 5 cmH2O (2.5 vs. 1.6). It seems that sex, history of cardiac failure, baseline CVP level, and hypertension do not have a significant effect in this regard.

Effect of application of pulse contour cardiac output monitoring technology on delayed resuscitation of patients with extensive burn in a mass casualty

Objective To investigate the effect of the application of pulse contour cardiac output (PiCCO) monitoring technology on delayed resuscitation of patients with extensive burn in a mass casualty. Methods The clinical data of 41 patients injured in Kunshan dash explosion hospitalized in the First Affiliated Hospital of Soochow University, the 100th Hospital of the People's Liberation Army, and Suzhou Municipal Hospital were retrospectively analyzed. The patients were divided into traditional monitoring group (T, n=22) and PiCCO monitoring group (P, n=19) according to the monitoring technic during delayed resuscitation. The input volumes of electrolyte, colloids, and water of patients in the two groups within 2 hours after admission, the first, second, and third 8 hours post injury (HPI), and the first 24 HPI were recorded. The fluid infusion coefficients of patients in the two groups within 2 hours after admission, the first, second, and third 8 HPI, and the first, second, third, and fourth 24 HPI were calculated. The urine volume, mean arterial pressure (MAP), and central venous pressure (CVP) of patients in the two groups at post injury hour (PIH) 8, 16, 24, 48, 72, and 96 were recorded. The blood lactate, base excess, hematocrit (HCT), and platelet count of patients in the two groups at PIH 24, 48, 72, and 96 were recorded. Complications and death of patients in the two groups were recorded. Data were processed with analysis of variance for repeated measurement, Chi-square test, t test, and Wilcoxon test. The deviations between figure 2 and the fluid infusion coefficients of the first or second 24 HPI, and the deviations between figure 1 and the fluid infusion coefficients of the second, third or fourth 24 HPI were calculated, and the three groups deviations were analyzed by Pearson correlation analysis. Results (1) The input volumes of electrolyte of patients in group P were significantly more than those in group T within the first 8 and 24 HPI (with Z values respectively -3.506 and -2.654, P 0.05). There was obviously positive correlation between the deviations of figure 1 and the fluid infusion coefficient of the second 24 HPI and that of the fourth 24 HPI (r=0.695, P<0.01). (3) The urine volumes and MAP of patients in the two groups were similar at each time point (with Z values from -1.884 to 0, P values above 0.05). The CVP of patients in group P were significantly higher than that in group T at PIH 16, 24, 48, and 72 (with Z values from -4.341 to -2.213, P<0.05 or P<0.01), and the CVP of patients in the two groups were similar at the other time points (with Z values respectively -0.132 and -1.208, P values above 0.05). The blood lactate of patients in group P was significantly higher than that in group T at PIH 72 (Z= -2.958, P<0.01) , and the blood lactate of patients in the two groups were similar at the other time points (with Z values from -1.742 to -0.433, P values above 0.05). The base excess of patients in group P were significantly lower than that in group T at PIH 24, 48, 72, and 96 (with Z values from -4.970 to -4.734, P values below 0.01). The HCT of patients in the two groups were similar at PIH 24, 48, 72, and 96 (with Z values from -2.239 to -0.196, P values above 0.05). There were significant differences in the platelet count of patients in the two groups at PIH 24, 72, and 96 (with Z values from -4.578 to -2.512, P<0.05 or P<0.01). (4) There were 15 cases in group T accompanied by complications, and 7 cases died, while 13 cases in group P accompanied by complications, and 9 cases died. The occurrence of complications and death of patients in the two groups were similar (with χ2 values respectively <0.001 and 1.306, P values above 0.05). Conclusions On the basis of traditional burn shock monitoring index, the effect of fluid resuscitation in patients with severe burn monitored by PiCCO technology is not so good and still needs further clinical research. Key words: Burns; Electrolytes; Resuscitation; Pulse contour cardiac output monitoring technology

Measurement of Central Venous Pressure Using Ultrasound in Emergency Department.

Background:In order to assessment of intravascular fluid measurement of central venous pressure (CVP) is used via central venous catheterization (CVC). This procedure is highly invasive and may cause serious complications such as pneumothorax, infection, hematoma and etc. It is so valuable procedure if we can uses a less invasive or noninvasive procedure to assess patients intravascular fluid in critical positions.Objectives:In this study, the ultrasound was used to measure the central venous pressure (CVP).Patients and Methods:In this study, patients with Central venous catheterization were selected using simple random sampling. The largest diameter of longitudinal, transverse views and the cross-section of inferior vena cava (IVC) and internal jugular vein (IJV) were measured using the ultrasound in the bedside of the patients. Central venous pressure was measured using routine methods. Correlations between variables were analyzed using SPSS and linear regression.Results:Twenty patients with the mean age of 60.3 were studied. The main reason for cardiac catheterization was shock. There are no relationship between anterior posterior diameter of inferior vena cava and CVP of patients (P = 0.257). The longest diameter of IVC in ultrasonographic transverse view had significant association with CVP of patients (P = 0.045) but in patients with BMI > 25 it was not significant. Cross section of internal jugular vein had significant association with CVP of patients (P = 0.003). Longitudinal diameter of internal jugular vein had no significant association with CVP of patients (P = 0.052), but transverse diameter of internal jugular generally had significant association with CVP of patients (P = 0.003). Cross section of internal jugular had significant association with CVP (P = 0.001).Conclusions:Noninvasive assessment of the patient hydration condition using the ultrasound is a simple and practicable measure in emergency. With regard to the considerations, it is possible to estimate CVP via diameter measurement and cross-section of the central veins.

Abstract 18452: Importance of “Dynamic” Rather Than “Static” Central Venous Pressure and Venous Capacitance in Fontan Circulation During Exercise

Background: High central venous pressure (CVP) is a key driver of developing late complications in patients after Fontan operation. However, we often realize diversity of clinical outcome among patients with similar levels of CVP measured at resting condition during catheterization. We hypothesized that CVP variably increases with exercise and that degree of the increase is associated with clinical outcomes. We also hypothesized that venous capacitance (VC) is an important determinant of the CVP elevation. Methods: Dynamic changes in CVP estimated from continuous monitoring of peripheral venous pressure were measured during treadmill exercise (TM) in 21 Fontan patients and 10 age-matched control patients with biventricular (BV) circulation. The VC was calculated during temporal occlusion of inferior vena cava (IVC) at the time of catheterization. Results: Fontan patients exhibited significantly shorter duration of exercise with limited increases in heart rate and cardiac output. CVP significantly increased during exercise in both groups, but the degree of CVP elevation was much higher in Fontan patients than in controls (Fontan: from 10.8 to 18.4 mmHg vs. control: from 4.3 to 8.8 mmHg, P&lt;0.05). Importantly, maximum CVP during exercise in Fontan group varied considerably among patients with similar resting CVP, and is significantly and positively correlated with a liver fibrosis marker of type 4 collagen 7S (P &lt;0.01). Furthermore, maximum CVP during exercise in Fontan group negatively correlated with the VC, but not with pulmonary resistance. Conclusions: CVP of the Fontan circulation easily rises during exercise in proportion to the reduced VC, and the degree of CVP rise may be a contributor of hepatic complication. These results suggest the importance of assessing dynamic CVP in patients after Fontan operation. The results also suggest potential importance of daily life modification and/or medical treatment to minimize the dynamic changes in CVP to improve the prognosis of Fontan patients. VC may be a viable target for this purpose.

Liver stiffness measurements for evaluation of central venous pressure in congenital heart diseases

ObjectiveTransient elastography (TE; Fibroscan, Echosens, France) is a non-invasive and reproducible approach to assess liver stiffness (LS). LS has been reported to be associated with fibrosis but central venous pressure...

Peripheral venous pressure as a reliable predictor for monitoring central venous pressure in patients with burns.

Sir, The article by Sherif et al.[1] on peripheral venous pressure (PVP) was very interesting. Fluid resuscitation of burns patient is extremely important part of initial management. Peripheral access for fluid resuscitation must be used as it helps in faster initiation of fluid therapy. The use of PVP to monitor hemodynamics and volume status is very innovative. The volume of fluid infusion is calculated as per the formulae based on percentage body surface area affected by burns. The use of hemodynamic monitoring has not been proven to be of much importance in the management of such patients. Most of the studies quoted in this study that have shown any use of invasive monitoring have used pulmonary artery catheter. The benefit of both central venous pressure (CVP) and pulmonary capillary wedge pressure for hemodynamic monitoring have been questioned in various trials and meta-analyses.[2,3] We doubt if there can be a worthwhile role of PVP to help in volume resuscitation of burn patients. The use of central venous access is also important in the hemodynamically unstable patient because it helps to give vasopressor medications, which cannot be given by the peripheral route. These patients may also need mechanical ventilation, which mandates the use of sedative and analgesic medication. Thus in such patients requiring multiple infusions central venous access would be necessary as peripheral access would not be satisfactory in such cases. The Bland-Altman analysis has shown in the study a difference of −1.2 with an standard deviation of +1.96, which means that PVP and CVP can differ by a range of 5.12 mm Hg more to 2.72 mm Hg less.[4] This is not a clinically acceptable margin of error for the use of PVP as a surrogate for CVP. The interpretation of data is thus always a clinical judgment. These findings are similar to the Tugrul et al.[5] study that showed a good correlation but poor clinical agreement. We feel the range is too wide for effective utilization at the bedside. The [Figure 2] is written to be depicting the hourly mean difference between CVP and PVP but in the graph there is no hour axis. We think it's the scatter diagram of the data which has been wrongly labeled. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Peripheral venous pressure as a reliable predictor for monitoring central venous pressure in patients with burns.

Background:Optimizing cardiovascular function to ensure adequate tissue oxygen delivery is a key objective in the care of critically ill patients with burns. Hemodynamic monitoring may be necessary to optimize resuscitation in serious burn patients with reasonable safety. Invasive central venous pressure (CVP) monitoring has become the corner stone of hemodynamic monitoring in patients with burns but is associated with inherent risks and technical difficulties. Previous studies on perioperative patients have shown that measurement of peripheral venous pressure (PVP) is a less invasive and cost-effective procedure and can reliably predict CVP.Objective:The aim of the present prospective clinical study was to determine whether a reliable association exists between changes in CVP and PVP over a long period in patients admitted to the Burns Intensive Care Unit (BICU).Subjects and Methods:The CVP and PVP were measured simultaneously hourly in 30 burns patients in the BICU up to 10 consecutive hours. The predictability of CVP by monitoring PVP was tested by applying the linear regression formula and also using the Bland–Altman plots of repeated measures to evaluate the agreement between CVP and PVP.Results:The regression formula revealed a reliable and significant association between CVP and PVP. The overall mean difference between CVP and PVP was 1.628 ± 0.84 mmHg (P < 0.001). The Bland–Altman diagram also showed a perfect agreement between the two pressures throughout the 10 h period.Conclusion:Peripheral venous pressure measured from a peripheral intravenous catheter in burns patients is a reliable estimation of CVP, and its changes have good concordance with CVP over a long period of time.

Can Stroke Volume Variation Be an Alternative to Central Venous Pressure in Patients Undergoing Kidney Transplantation?

BackgroundStroke volume variation (SVV) is known to be a simple and less invasive hemodynamic parameter for evaluating fluid responsiveness and preload status. Central venous pressure (CVP) has been targeted to achieve an adequate level for improving the graft perfusion and long-term graft function in kidney transplantation (KT) recipients, despite the various potential complications. The aim of this study was to investigate whether SVV could substitute for CVP in guiding intravascular volume management during KT. MethodsThis retrospective study evaluated 635 patients who underwent KT because of end-stage renal disease. Hemodynamic variables including CVP and SVV were obtained before skin incision (T1), 5 minutes after iliac vein clamping (T2), and 10 minutes after renal graft reperfusion (T3). The ability of SVV to predict CVP level was investigated with receiver operating characteristic (ROC) curve analysis. ResultsCVPs were 6.0 ± 2.6, 8.6 ± 2.7, and 9.3 ± 2.5 mm Hg, and SVVs were 6.9 ± 3.0, 5.0 ± 2.1, and 4.3 ± 2.1% at T1, T2, and T3, respectively. ROC analysis showed that the discriminative power of SVV was fairly good with an area under the ROC curve of 0.70 (95% confidence interval, 0.67–0.72) for a CVP of 8 mm Hg, and that an optimal cutoff value of SVV was 6% as an alternative to CVP of 8 mm Hg during KT. ConclusionsSVV may replace CVP in the volume management of patients who have undergone KT. Our results suggest that SVV can guide volume management to improve graft perfusion at critical time points during KT.

Cerebral Circulation in Patients With Fontan Circulation: Assessment by Carotid Arterial Wave Intensity and Stiffness

Information about the cerebral circulation in the Fontan physiology is scarce. We tested our hypothesis that cerebral perfusion is impaired in the Fontan circulation by analyzing wavefront behavior (wave intensity) and assessing arterial stiffness at the carotid artery. The carotid arterial wave intensity and stiffness were computed in 34 consecutive Fontan patients (11.5±8.6 years) and 20 control subjects (13.4±6.0 years) using an echocardiographic vascular tracking system, which enabled simultaneous measurements of instantaneous carotid arterial pressure and flow velocity. The carotid arterial blood flow was significantly lower in the Fontan patients than in the controls (p<0.05). Wave intensity analysis demonstrated a significant decrease in the compression and acceleration wave, an important forward traveling wave for cerebral circulation, in the Fontan patients compared with the control subjects (31.0±2.6 versus 48.1±4.4 mm Hg⋅m⋅s3⋅10(3); p=0.001). In addition, the negative wave intensity normalized to the first positive wave, representing a wave reflection from peripheral cerebral vessels, was significantly increased in the Fontan patients compared with that in control subjects. Carotid arterial stiffness and central venous pressure were also significantly increased in the Fontan patients and were independent determinants of the decreased first positive wave, suggesting the pathophysiologic importance of carotid arterial stiffness and central venous pressure as inflow and outflow resistance to the cerebral circulation, respectively, in the Fontan physiology. These results suggest impaired cerebral perfusion caused by vascular stiffening and high central venous pressure in patients with Fontan circulation. Longitudinal studies examining the association between cerebral circulation and neurodevelopmental outcome after Fontan operation are warranted.

The condition of the microcirculatory channel of the nail bed of the upper extremities and changes of central venous pressure in patients with the second stage of essential hypertension depending on the structure of the diurnal rhythm of arterial pressure

The peculiarities of changes of the microcirculation of the nail-bed and central venous pressure (CVP) have been presented in the poper in patients the with 2nd stage of essential hypertension depending on different variants of the circadian rhythm of arterial pressure. An inverse interdependence has been established between the level and a decrease of the specific gravity of the functioning capillaries in the patients with a low (non-dipper) and negative (night-picker) diurnal index of arterial pressure that con be used as diagnostic criteria of a high risk of possible complications of essential hypertension.

288: Liver stiffness: a new, rapid and non-invasive method of central venous pressure evaluation in patients with congenital heart disease

Transient elastography is a rapid, noninvasive and reproducible approach to assess liver fibrosis by measuring liver stiffness (LS). However, because the liver is enveloped by a capsule, any variation in parenchymal fluid content could theoretically affect LS. LS has been correlated to central venous pressure (CVP) in an animal model. We aimed to determine the correlation between LS and CVP in children and adults with congenital heart disease. In this ongoing prospective study, all patients referred for right heart catheterization were included. Measurements of mean right atrial pressure were obtained under general anesthesia (Fi02=21%) using an Optitorque 5 French catheter. The patients underwent 10 LS measurements (median value taken as representive) by transient elastography (Fibroscanâ, Echosens, France) within the 24 hours before catheterization. The results of LS are expressed in kilopascals (kPa). Eleven children (mean age=8±6 yo, 54% male) and 6 adults (mean age=34±17 yo, 66% male) have been included so far. Catheterism indications were pulmonary angioplasty (n=5), Melody valve implantation (n=1), fenestration occlusion after a Fontan procedure (n=1) and pre operative assessement of a complex congenital heart defect (n=10). Mean right atrial pressure was 9,1±3,9 mmHg and mean LS was 8,4±4,2 kPa. Correlation between LS and mean right atrial pressure was excellent for these first 17 patients (r=0,87). Liver stiffness is a new, rapid and reliable method to evaluate CVP in patients with congenital heart disease. This non invasive parameter could potentially be usefull for patients in whom CVP play a key role, especially in patients with a Fontan circulation.

The influence of positive end-expiratory pressure on central venous pressure in patients with severe craniocerebral injury

To observe the impact of positive end-expiratory pressure (PEEP) on central venous pressure (CVP) in mechanically ventilated patients with severe craniocerebral injury. A prospective, interventional, self-control study was conducted. Thirty severe craniocerebral injury patients with central respiratory failure were enrolled. The changes in CVP, mean arterial pressure (MAP), heart rate (HR) and pulse oxygen saturation [SpO2] were monitored at different PEEP levels [0, 3, 6, 9, 12, 15 cm H2O; 1 cm H2O=0.098 kPa] during mechanical ventilation and after weaning of mechanical ventilation. The influences of PEEP and its discontinuance on haemodynamics and oxygenation were analyzed. The values of CVP [cm H2O] were increased when PEEP increased (from 7.9±3.1 to 13.1±3.7), a linear correlation was found (R=0.509, P=0.000), and linear regression equation was CVP [cm H2O]=7.774+0.368×PEEP [cm H2O]; CVP was elevated about 0.368 cm H2O when PEEP increased 1 cm H2O. CVP values significantly decreased during discontinuance of mechanical ventilation, as compared to those measured at different PEEP levels during mechanical ventilation (F=24.429, P=0.000). The values of MAP, HR and SpO2 showed no significant change with increase of PEEP levels [MAP (mm Hg, 1 mm Hg=0.133 kPa): from 81.6±10.4 to 85.6±10.6; HR (beats per minute): from 79.9±13.5 to 88.1±15.4; SpO2: from 0.968±0.036 to 0.975±0.033, all P>0.05] in mechanically ventilated patients, but discontinuance of mechanical ventilation could significantly increase the levels of MAP and HR (95.3±8.4 and 94.9±10.3, respectively) and lower SpO2 levels (0.928±0.036, all P=0.000). CVP values were overestimated during an increase in PEEP in mechanically ventilated patients with severe craniocerebral injury. CVP was increased about 0.368 cm H2O following an increase of PEEP of 1 cm H2O, whereas the values of MAP, HR and SpO2 showed no significant change with increase in PEEP levels. This study could offer a theoretical base in the correct assessment of CVP values at different PEEP levels without discontinuation of mechanical ventilation.

Abstract 17313: Bedside Ultrasound for Serial Assessment of Central Venous Pressure in Patients with Volume Overload

Background: Using bedside ultrasound, we have previously shown that a greater than 17% increase in internal jugular vein (IJ) cross sectional area (CSA) during Valsalva rules out elevated right atrial pressure (RAP &gt; 12mmHg, NPV 94%). This occurs because venous compliance increases nonlinearly with increasing pressure. Here, we sought to validate this US test in the first longitudinal study of patients undergoing acute volume removal during hemodialysis (HD) as well as patients undergoing diuresis for acute decompensated heart failure (ADHF). Methods: Images of the right IJ were captured using portable bedside US before and during the strain phase of a standardized Valsalva maneuver (Fig 1) on hospitalized patients who were either admitted for ADHF or undergoing HD. For HD patients (n=11), percent change in IJ CSA with Valsalva (ΔCSA) was assessed both before and after HD treatment. For ADHF patients (n=37), ΔCSA was measured both at admission and discharge. Results: For HD patients, analysis of US images detected elevated filling pressures (ΔCSA &lt;17%) in 11 of the patients studied. In these subjects, a mean fluid volume of 1.8L was removed and 10 subjects demonstrated an increased ΔCSA after HD (ΔCSA increase of 45 ± 40%, p17% indicating restoration of normal filling pressures. Of the 37 ADHF patients studied with elevated filling pressures at admission (ΔCSA &lt;17%), 27 demonstrated euvolemia after diuresis (ΔCSA increase of 57 ± 157%, p&lt;0.01) and an average length of stay of 7.8 days. Conclusion: US of the IJ can be used to examine intravascular volume status in response to fluid changes that occur over the course of hours (HD) or days (ADHF). This simple bedside technique could be utilized for monitoring volume changes, both acutely and longer term, to guide volume management and overcome some of the difficulties associated with traditional visual assessment of jugular venous pulsations.

Peripheral venous pressure as an alternative to central venous pressure in patients undergoing laparoscopic colorectal surgery

BackgroundPeripheral venous pressure (PVP) is strongly correlated with central venous pressure (CVP) during various surgeries. Laparoscopic surgery in the Trendelenburg position with pneumoperitoneum typically increases CVP. To determine whether PVP convincingly reflects changes in CVP, we evaluated the correlation between PVP and CVP in patients undergoing laparoscopic colorectal surgery. MethodsBoth CVP and PVP were measured simultaneously at predetermined time intervals during elective laparoscopic colorectal surgery in 42 patients without cardiac disease. The pairs of venous pressure measurements were analysed for correlation, and the Bland–Altman plots of repeated measures were used to evaluate the agreement between CVP and PVP. ResultsA total of 420 data pairs were obtained. The overall mean CVP was 11.3 (sd 4.5) mm Hg, which was significantly lower than the measured PVP of mean 12.1 (4.5) mm Hg (P=0.005). There was a strong positive correlation between overall CVP and PVP (correlation coefficient=0.96, P<0.0001). The mean bias (PVP–CVP) corrected for repeated measurements using random-effects modelling was 0.9 mm Hg [95% confidence interval (CI) 0.54–1.19 mm Hg] with 95% limits of agreement of −1.2 mm Hg (95% CI −1.75 to −0.62 mm Hg) to 2.9 mm Hg (95% CI 2.35–3.48 mm Hg). ConclusionsPVP displays a strong correlation and agreement with CVP under the increased intrathoracic pressure of pneumoperitoneum in the Trendelenburg position and may be used as an alternative to CVP in patients without cardiac disease undergoing laparoscopic colorectal surgery.