Venous Pressure In Patients Research Articles

Nitroglycerin versus milrinone for low central venous pressure in patients undergoing laparoscopic hepatectomy: a double-blinded randomized controlled trial

BackgroundConventional anesthesia used to reduce central venous pressure (CVP) during hepatectomy includes fluid restriction and vasodilator drugs, which can lead to a reduction in blood perfusion in vital organs and may counteract the benefits of low blood loss. In this study, we hypothesized that milrinone is feasible and effective in controlling low CVP (LCVP) during laparoscopic hepatectomy (LH). Compared with conventional anesthesia such as nitroglycerin, milrinone is beneficial in terms of intraoperative blood loss, surgical environment, hemodynamic stability, and patients’ recovery.MethodsIn total, 68 patients undergoing LH under LCVP were randomly divided into the milrinone group (n = 34) and the nitroglycerin group (n = 34). Milrinone was infused with a loading dose of 10 µg/kg followed by a maintenance dose of 0.2–0.5 µg/kg/min and nitroglycerin was administered at a rate of 0.2–0.5 µg/kg/min until the liver lesions were removed. The characteristics of patients, surgery, intraoperative vital signs, blood loss, the condition of the surgical field, the dosage of norepinephrine, perioperative laboratory data, and postoperative complications were compared between groups. Blood loss during LH was considered the primary outcome.ResultsBlood loss during hepatectomy and total blood loss were significantly lower in the milrinone group compared with those in the nitroglycerin group (P < 0.05). Both the nitroglycerin group and milrinone group exerted similar CVP (P > 0.05). Nevertheless, the milrinone group had better surgical field grading during liver resection (P < 0.05) and also exhibited higher cardiac index and cardiac output during the surgery (P < 0.05). Significant differences were also found in terms of fluids administered during hepatectomy, urine volume during hepatectomy, total urine volume, and norepinephrine dosage used in the surgery between the two groups. The two groups showed a similar incidence of postoperative complications (P > 0.05).ConclusionOur findings indicate that the intraoperative infusion of milrinone can help in maintaining an LCVP and hemodynamic stability during LH while reducing intraoperative blood loss and providing a better surgical field compared with nitroglycerin.Trial registrationChiCTR2200056891,first registered on 22/02/2022.

Low Mean Perfusion Pressure Indexed to Body Surface Area is a Powerful Predictor of Poor Outcomes After Heart Transplantation in Patients With High Pre-Transplant Venous Pressure: A Clinical Study With Physiological Insights From Mathematical Modelling of Biventricular Heart Failure

The deleterious consequences of chronically elevated venous pressure in patients with profound right ventricular or biventricular dysfunction are well known, including renal and hepatic dysfunction, and volume overload. The only option for these patients, if they fail optimal medical treatment, is a heart transplant, as they are not candidates for left ventricular assist device therapy. Mean perfusion pressure (MPP) is important in the outcomes of critically ill patients with high venous pressure. The question arises whether MPP is important for the outcomes of heart transplants in patients with elevated pre-transplant venous pressure. Medical management of heart failure patients with reduced ejection fraction involves lowering the systemic afterload with vasodilators while awaiting a transplant. We hypothesised that when venous pressure is elevated prior to transplant, a substantial reduction in systemic arterial elastance (Ea) through vasodilation may significantly decrease MPP, resulting in compromised end-organ function and consequent unfavourable outcomes after heart transplantation. This study aims to investigate whether a low MPP serves as a risk factor for adverse outcomes in heart transplant recipients with high venous pressure. A retrospective analysis was conducted on 250 heart transplant recipients undergoing isolated heart transplantation at a single institution from October 2012 to March 2020. Right atrial pressure (RAP) of more than 15 mmHg was considered high. Additionally, Ea calculated as the ratio of end-systolic pressure to stroke volume, and MPP calculated as the difference between mean arterial pressure and RAP were considered in our analysis. The outcomes of transplantation were measured in terms of 90-day mortality and survival up to 7 years. High RAP was a significant risk factor for short-term and medium-term survival if Ea was low (<2.7 mmHg/mL, the median value). This group had 39.39% in-hospital mortality compared to 14.49% for RAP<15 mmHg (p∼0.005). When Ea was high, this difference in survival was not evident: 8% for RAP<15 mmHg vs 4.8% for RAP>15 mmHg (p∼0.550). This effect was mediated through a lower MPP, and the mortality due to lower MPP increased strikingly with higher body surface area (BSA). A negative correlation was observed between MPP indexed to BSA (MPPI) and the Model for End-Stage Liver Disease score (r∼-0.3580, p<0.0001) as well as creatinine (r∼-0.3551, p<0.0001). MPPI less than 40 mmHg/m2 was associated with poorer short-term (23.2% for MPPI<40 mmHg/m2 vs 7.1% for MPPI>40 mmHg/m2, p∼0.001) and medium-term survival. The impact of high RAP and low Ea on survival was evident even on medium-term follow-up; only 30% survival at 7 years follow-up for high RAP and low Ea vs 75% for RAP<15 mmHg (p∼0.0033). The acceptable blood pressure during vasodilator therapy in patients with high RAP needs to be higher, especially in those with higher BSA. MPPI less than 40 mmHg/m2 is a risk factor for survival, in the short and medium-term, after heart transplantation.

Association Between the Liver Fibrosis Markers and Scores, and Hemodynamic Congestion Assessed by Peripheral Venous Pressure in Patients With Acute Heart Failure.

Background Peripheral venous pressure (PVP) has been shown to be a reliable surrogate for right atrial pressure in assessing congestion in patients with heart failure (HF). Liver fibrosis markers and scores can be useful in assessing organ injury in patients with acute HF. This study aimed to investigate the association of liver fibrosis markers and scores with PVP in patients with acute HF. Methods and Results The 7S domain of the collagen type IV N-terminal propeptide (P4NP 7S), aspartate aminotransferase-to-platelet ratio index, fibrosis-4, and nonalcoholic fatty liver disease fibrosis score were determined along with PVP measurements before discharge in 229 patients with acute HF. The strongest correlation with PVP was found for P4NP 7S (Pearson r=0.40). Patients with high P4NP 7S levels (≥median [6.2 ng/mL]) had an increased risk of cardiovascular death or HF hospitalization (adjusted hazard ratio [HR], 1.80 [95% CI, 1.09-3.04], P=0.02). The concomitant high PVP (≥mean [8 mm Hg])/high P4NP 7S group, in contrast to the high PVP/low P4NP 7S or low PVP/high P4NP 7S group, had a significant risk relative to the low PVP/low P4NP 7S group for cardiovascular death or HF hospitalization (adjusted HR, 2.63 [95% CI, 1.43-5.05], P=0.002). A sustained elevation in PVP for 1 month postdischarge was associated with a persistent increase in P4NP 7S. Conclusions The study demonstrated the relationship between the liver fibrosis marker P4NP 7S and congestion. PVP and P4NP 7S could be useful for assessing congestion-related organ injury and predicting prognosis in patients with acute HF.

Location and extent of cavernous transformation of the portal vein dictates different visceral side revascularization in Meso-Rex bypass

BackgroundAs an emerging standard of care for portal vein cavernous transformation (PVCT), Meso-Rex bypass (MRB) has been complicated and variated. The study aim was to propose a new classification of PVCT to guide MRB operations.MethodsDemographic data, the extent of extrahepatic PVCT, surgical methods for visceral side revascularization, intraoperative blood loss, operating time, changes in visceral venous pressure before and after MRB, postoperative complications and the condition of bypass vessels after MRB were extracted retrospectively from the medical records of 19 patients.ResultsThe median age of the patients (13 males and 6 females) was 32.5 years, while two patients were underage. Causes of PVCT can be summarized as follows: thrombophilia such as dysfunction of antithrombin III or proteins C; secondary to abdominal surgeries; secondary to abdominal infection or traumatic intestinal obstruction, and unknown causes. Intraoperatively, the median operation time was 9.5 h (7–13 h), and the intraoperative blood loss was 300 mL (100-1,600 mL). Ten cases used autologous blood vessels while 10 used allogeneic blood vessels. The vascular anastomosis was divided into the following types according to the site and approach: Type (T) 1-PV pedicel type, T2-confluence type, T3-major visceral vascular type; and T4-collateral visceral vascular type. Furthermore, the visceral venous pressure before and after MRB dropped significantly from 36 cmH2O (28–44) to 24.5 cmH2O (15–31) (P < 0.01). Postoperatively, one patient had delayed wound healing, two developed biochemical pancreatic fistulae, one experienced lymphatic leakage, the former caused by heat damage of the pancreatic tissues, the latter by cutting lymphatic vessels in the mesentery or removing the local lymph nodes during the process of separating the superior mesenteric vein, and one was re-operated on for an intervening intestinal fistulae. Postoperative enhanced CT scans revealed a significant improvement in abdominal varix in the patients with patent bypass, and at the 1-year postoperative follow-up, enhanced CT scans of six patients showed that the long axis of the spleen was reduced by ≥ 2 cm.ConclusionsMRB can effectively reduce visceral venous pressure in patients with PVCT. It is feasible to determine the PVCT type according to the extent of involvement and to choose individualized visceral side revascularization performances.

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

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

The evaluation of portal hypertension in cirrhotic patients with spectral computed tomography.

Iodine concentrations measured using dual-energy spectral CT (DESCT) have been recently proposed as providing good performance for examining tissues hemodynamics. To evaluate the diagnostic efficacy of DESCT-derived parameters in evaluating portal venous pressure in patients with liver cirrhosis. A total of 71 patients with liver cirrhosis who underwent percutaneous transhepatic portal vein puncture procedures were included in this study. All participants underwent DESCT and gastrointestinal endoscopy within one month before the operation. The direct portal venous pressure of each participant was measured preoperatively. Stepwise multivariate linear regression analysis showed that the iodine concentrations in the portal vein and hepatic parenchyma during the portal venous phase and the platelet count were independently correlated with the direct portal venous pressure (P < 0.001, P < 0.001, and P = 0.030, respectively). Receiver operating characteristic analysis revealed that the normalized iodine concentration of the hepatic parenchyma had the best performance for identifying clinically significant portal hypertension (≥10 mmHg), esophageal varices, and high-risk esophageal varices (the area under the curve values were 0.951, 0.932, and 0.960, respectively). The normalized iodine concentration of the hepatic parenchyma is a reliable parameter to non-invasively assess portal venous pressure in patients with liver cirrhosis.

The effects of positive end-expiratory pressure on central venous pressure in patients with different chest wall elastic resistance

Objective: To investigate the role of chest wall elastic resistance in determining the effects of positive end-expiratory pressure (PEEP) on central venous pressure (CVP) in patients with mechanical ventilation (MV). Methods: In this prospective study, according to the median of ratio of chest wall elastic resistance to respiratory system elastic resistance (Ers), patients were divided into high chest wall elastic resistance group (Ecw/Ers≥0.24) and low chest wall elastic resistance group [elastance of chest wall (Ecw)/Ers<0.24]. PEEP was set at 5, 10, 15 cmH2O (1 cmH2O=0.098 kPa) respectively. Clinical data including CVP, heart rate (HR), blood pressure (BP) and respiratory mechanics were recorded. Results: Seventy patients receiving MV were included from November 2017 to December 2018. Clinical characteristics including age, BP, HR, baseline PEEP, the ratio of arterial oxygen partial pressure to fractional inspired oxygen (P/F) and comorbidities were comparable in two groups. However, patients with high Ecw/Ers ratio presented higher body mass index (BMI) than those with low Ecw/Ers ratio[ (25.4±3.2) kg/m2 vs. (23.4±3.2) kg/m2, P=0.011]. As PEEP increased from 5 cmH2O to 10 cmH2O, CVP in high Ecw/Ers group increased significantly compared with that in low Ecw/Ers group [1.75(1.00, 2.13) mmHg (1 mmHg=0.133kPa) vs. 1.50(0.50, 2.00)mmHg,P=0.038], which was the same as PEEP increased from 10 cmH2O to 15 cmH2O [2.00(1.50, 3.00)mmHg vs. 1.50(1.00, 2.00)mmHg,P=0.041] or PEEP increased from 5 cmH2O to 15 cmH2O [ 3.75(3.00,4.63)mmHg vs. 3.00(1.63, 4.00)mmHg, P=0.012]. When PEEP increased from 5 cmH2O to 10 cmH2O, 10 cmH2O to 15 cmH2O and 10 cmH2O to 15 cmH2O, there were significant correlations between Ecw/Ers and CVP elevation (r=0.29, P=0.016; r=0.31, P=0.011; r=0.31, P=0.01 respectively). Conclusions: In patients receiving mechanical ventilation, elevation of PEEP leads to a synchronous change of CVP, which is corelated with patients' chest wall elastic resistances.

A randomized comparison between pulse pressure variation and central venous pressure in patients undergoing renal transplantation.

Background and Aims:Intraoperative fluid management is important in renal transplant recipients with end-stage renal disease. Conventionally, central venous pressure (CVP) has been used to guide perioperative fluid administration but with high incidence of poor graft outcome. There is a requirement of reliable parameter to guide the fluid therapy in these patients so as to minimize the perioperative complications and improve the outcome. Hence, this study was conducted.Material and Methods:This prospective study included 75 patients of chronic kidney disease undergoing renal transplantation. Patients were divided into two groups. Group A (control group): Intraoperative fluids were guided by CVP; Group B: Intraoperative fluids were guided by pulse pressure variation (PPV). Primary outcome measure of this study was incidence of delayed graft functioning, i.e., need of hemodialysis within 7 days of renal transplant. Secondary outcome measures were incidence of perioperative hypotension, post-transplant pulmonary edema, tissue edema, and lactic acidosis.Results:Total amount of fluid before reperfusion was significantly greater in the control group (P = 0.005). However, the total amount of fluid required at the end of surgery was comparable. Delayed graft functioning was seen only in CVP group, although it was not statistically significant. The postoperative tissue edema was more in CVP group (P = 0.03). The postoperative nausea and vomiting, pulmonary edema, and mechanical ventilation were more in CVP group but not statistically significant. Increase in lactate value was more in CVP group.Conclusion:Perioperative fluid guidance by PPV is better than central venous pressure in renal transplant patients.

Posisi Pasien terhadap Tekanan Vena Sentral

This study aims to identify an increase in central venous pressure in patients given lateral or prone position interventions and to identify the rise in central venous pressure in patients given semi-fowler position intervention in the intensive care unit. This study uses a Quasi-Experimental method with a Case-Control design. The results obtained are the p-value of 0.000, meaning that the research significantly affects the positioning of the central venous pressure (CVP). In conclusion, there was an increase in the average CVP value before and after the passive position intervention was -1,967 cmH2O; on the other hand, there was a decrease in the average CVP value before and after the semi fowler position intervention was 1,867 cmH2O.&#x0D; &#x0D; Keywords: Supine and Semi Fowler Position, Central Venous Pressure

A comparative study of pulse pressure variation, stroke volume variation and central venous pressure in patients undergoing kidney transplantation.

Optimal intraoperative fluid management guided by central venous pressure (CVP), a traditional intravascular volume status indicator, has improved transplanted graft function during kidney transplantation (KT). Pulse pressure variation (PPV) and stroke volume variation (SVV) - dynamic preload indexes - are robust predictors of fluid responsiveness. This study aimed to compare the accuracy of PPV and CVP against SVV in predicting fluid responsiveness in terms of cost-effectiveness after a standardised empiric volume challenge in KT patients. 36 patients undergoing living-donor KT were analysed. PPV, SVV, CVP and cardiac index (CI) were measured before and after fluid loading with a hydroxyethyl starch solution (7 mL/kg of ideal body weight). Patients were classified as responders (n = 12) or non-responders (n = 24) to fluid loading when CI increases were ≥10% or <10%, respectively. The ability of PPV, SVV and CVP to predict fluid responsiveness was assessed using receiver operating characteristic (ROC) curves. SVV and CVP measured before fluid loading were correlated with changes in CI caused by fluid expansion (ρ = 0.33, P = 0.049 and ρ = -0.37, P = 0.026) in contrast to PPV (ρ = 0.14, P = 0.429). The ROC analysis showed that SVV and CVP predicted response to volume loading (area under the ROC curve = 0.781 and 0.727, respectively; P < 0.05). Under the conditions of our study, SVV and CVP exhibited similar performance in predicting fluid responsiveness and could inform fluid management during KT as compared with PPV.

The Most Useful Method To Evaluate The Volume Status Of Critical Patients In The Emergency And Intensive Care Units: Point Of Care Ultrasound

Background: Accurate and rapid assessment of intravascular volume status of the patients in emergency services and intensive care units at diagnosis, treatment and follow-up stages is crucial yet rather difficult. The purpose of hemodynamic monitoring is to determine cardiovascular insufficiency and to provide the most suitable treatment for unstable patients in critical condition.&#x0D; Aim: The study aims to compare vena cava inferior diameter, vena cava inferior- collapsibility index (for spontaneously breathing patients) and vena cava inferior- distensibility index (for patients breathing on mechanical ventilation support) measurement by ultrasonography to central venous pressure measurement by placing invasive catheter for assessment of the intravascular volume status and making an accurate volume replacement in emergency service and intensive care units and to determine the correlation between them.&#x0D; Material and Methods: The study was carried out prospectively on the patients above the age of 18 who applied to the emergency service clinic between the dates of 01.06.2014 and 01.04.2015 or who stayed in the emergency intensive care unit between these dates. Measurements were taken from vena cava inferior in both the inspirium and expirium phases by using M mode and they were recorded in millimeter. Simultaneous central venous pressure measurements were performed on the patients by using manometric devices and the results were recorded in cm H2O.&#x0D; Results: 43.3% of the patients were female (n: 26) and 56.7% were male (n: 34), and the mean age is 70.58 ± 14.86. The study found high degree of positive correlation between central venous pressure and vena cava inferior diameters and high degree of negative correlation between vena cava inferior- collapsibility index . The study also found that there is a high degree of negative correlation between vena cava inferior- distensibility index and central venous pressure in patients receiving mechanical ventilatory support.&#x0D; Conclusion: Measurement of respiratory variation in vena cava inferior diameter by using ultrasonography is a quick, reliable, easily applicable, cost-efficient and non-invasive method in critical patients receiving mechanical ventilatory support or have spontaneous respiration in emergency services and intensive care units and it can be useful in assessing the volume status and estimating central venous pressure.

Влияние положения Тренделенбурга и пневмоперитонеума на сердечно-сосудистую систему при робот-ассистированной радикальной простатэктомии.

Introduction. Prostate cancer remains one of the most common malignant neoplasms of the genitourinary system. Robot-assisted radical prostatectomy (RARP) is currently considered the most effective option for the treatment of this pathology. Special conditions of this operation, such as long-term stay of the patient in the Trendelenburg position and pneumoperitoneum, affect blood pressure, vascular resistance and inotropic function of the heart. The clinical significance of this effect remains poorly understood. The aim of the study was to systematize new information about hemodynamic disorders in patients with pneumoperitoneum in the Trendelenburg position in RARP. Materials and methods. The search for relevant studies published before may 2019 was conducted in the electronic databases PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, Google Scholar using the keywords: «prostatectomy», «robotic surgery», «robotic assisted», «robotic laparoscopic radical prostatectomy», «pneumoperitoneum», «Trendelenburg position», «hemodynamics», «hemodynamic changes», «cardiac function», «cardiovascular function» without restrictions on the publication language. Forty one studies were identified, of which 15 were selected according to pre-defined inclusion criteria. Results. Most studies revealed an increase in arterial and central venous pressure in patients with pneumoperitoneum in the Trendelenburg position. Changes in stroke volume and cardiac output were multidirectional. There was also an increase in pulmonary artery pressure and filling pressure, a decrease in the aortic diameter and an increase in vascular resistance, a deterioration in central hemodynamic parameters, and increased microcirculation. Eleven studies did not show a negative effect of the Trendelenburg position and pneumoperitoneum on the cardiovascular system. The developed changes were easily controlled during anesthesia, and in the postoperative period, the indicators of the cardiovascular system returned to normal. In 4 studies, the negative impact of these factors was noted: the development of mitral valve dysfunction, a significant prolongation of the QT interval and an increase in blood pressure, and hemodynamic instability. Conclusions. The position of the Trendelenburg and pneumoperitoneum and in RARP are accompanied by hemodynamic disorders, most of which are controlled and reversible. Further studies with a longer follow-up period are needed to determine their clinical safety.

Relation of Peripheral Venous Pressure to Central Venous Pressure in Patients With Heart Failure, Heart Transplant, and Left Ventricular Assist Device

Peripheral venous pressure (PVP) monitoring is a noninvasive method to assess volume status. We investigated the correlation between PVP and central venous pressure (CVP) in heart failure (HF), heart transplant (HTx), and left ventricular assist device (LVAD) patients undergoing right heart catheterization (RHC). A prospective, cross-sectional study examining PVP in 100 patients from October 2018 to January 2020 was conducted. The analysis included patients undergoing RHC admitted for HF, post-HTx monitoring, or LVAD hemodynamic testing. Sixty percent of patients had HF, 30% were HTx patients, and 10% were LVAD patients. The mean PVP was 9.4 ± 5.3 mm Hg, and the mean CVP was 9.2 ± 5.8 mm Hg. The PVP and CVP were found to be highly correlated (r = 0.93, p < 0.00001). High correlation was also noted when broken down by HF (r = 0.93, p < 0.00001), HTx (r = 0.93, p < 0.00001), and LVAD groups (r = 0.94, p < 0.00005). In conclusion, there is a high degree of correlation between PVP and CVP in HF, HTx, and LVAD patients. PVP measurements can be used as a rapid, reliable, noninvasive estimate of volume status in these patient populations.

Assessment of Upper Extremity Venous Compliance in Patients With Abdominal Aortic Aneurysms

Abdominal aortic aneurysm (AAA) is associated with morphological and functional changes in both aneurysmal and non-aneurysmal arteries. However, it remains uncertain whether similar changes also exist in the venous vasculature. The aim of this study was to evaluate global venous function in patients with AAA and controls. This experimental study comprised 31 men with AAA (mean±standard deviation age 70.0±2.8 years) and 29 male controls (aged 70.6±3.4 years). Venous occlusion plethysmography (VOP) was used to evaluate arm venous compliance at venous pressures between 10 and 60mmHg in steps of 5mmHg. Compensatory mobilisation of venous capacitance blood (capacitance response) was measured with a volumetric technique during experimental hypovolaemia induced by lower body negative pressure (LBNP). The VOP induced pressure-volume curve was significantly less steep in patients with AAA (interaction, p<.001), indicating lower venous compliance. Accordingly, the corresponding pressure-compliance curves displayed reduced venous compliance at lower venous pressures in patients with AAA vs. controls (interaction, p<.001; AAA vs. control, p=.018). After adjusting for arterial hypertension, diabetes mellitus, hyperlipidaemia, chronic obstructive pulmonary disease, and smoking, VOP detected differences in venous compliance remained significant at low venous pressures, that is, at 10mmHg (p=.008), 15mmHg (p=.013), and 20mmHg (p=.026). Mean venous compliance was negatively correlated with aortic diameter (r=-.332, p=.010). Mobilisation of venous capacitance response during LBNP was reduced by approximately 25% in patients with AAA (p=.030), and the redistribution of venous blood during LBNP was negatively correlated with aortic diameter (r=-.417, p=.007). Men with AAA demonstrated reduced venous compliance and, as a result, a lesser capacity to mobilise peripheral venous blood to the central circulation during hypovolaemic stress. These findings imply that the AAA disease may be accompanied by functional changes in the venous vascular wall.

Comparison of Conventional Central Venous Pressure with Peripheral Venous Pressure and External Jugular Venous Pressure in Patients with Sepsis

Comparison of Conventional Central Venous Pressure with Peripheral Venous Pressure and External Jugular Venous Pressure in Patients with Sepsis

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.

Response of Jugular Venous Pressure to Exercise in Patients With Heart Failure and Its Prognostic Usefulness

Jugular venous pressure (JVP) has been established for the assessment of central venous pressure in patients with heart failure (HF), but data are limited regarding the response of JVP to exercise because of its complicated methods. Simplifying the estimation of JVP may be applied in such situations. JVP was assessed before and after the 6-minute walk test (6MWT) in 81 patients with HF using a simple method by which the JVP was considered high when the internal jugular venous pulsation on the right side was visually identified above the right clavicle in the sitting position. The primary outcome was a composite of cardiovascular death and hospitalization for worsening HF. None of the patients exhibited high JVP before the 6MWT and 11 patients (14%) had a high JVP after. The 6MWT distances were lower in patients with a high JVP after the 6MWT (338 ± 114 m) than those in patients without a high JVP (417 ± 78 m, p = 0.04). During a follow-up period of 13.4 ± 6.9 months, 11 patients died and 8 patients were hospitalized for worsening HF. The incidence of adverse cardiac events was higher in patients with a high JVP after the 6MWT (64%) than in patients without a high JVP after (64% vs 17%; hazard ratio, 7.52; 95% confidence interval, 2.69 to 20.83; p <0.001). In conclusion, high JVP after exercise was associated with exercise intolerance and poor prognosis. The response of JVP to exercise using this simple technique of physical examination may be a new approach for patients with HF for risk assessment.

Clinical value of portal venous pressure based on three dimensional reconstruction model of portal vein combined with finite element analysis in patients with portal hypertension

Objective To study the clinical value of three-dimensional CT reconstruction model of portal venous system combined with finite element analysis to measure portal venous pressure in patients with portal hypertension. Methods A retrospective study was conducted on 27 patients who were diagnosed to have portal hypertension at the Second Affiliated Hospital of Kunming Medical University from May 2016 to May 2018. There were 17 males and 10 females, with ages ranging from 34 to 77 years (mean 56 years). All these patients underwent transjugular intrahepatic portal venous shunt (TIPS) during which the portal venous pressure was measured. The imaging data was imported into the three-dimensional software of medical imaging to reconstruct the three dimensional model of portal vein, and the finite element analysis software of ANSYS was used to calculate the portal venous pressure by calculation with given boundary conditions. Pearson correlation was used to analyze the correlation between the actual measurement of portal venous pressure and the predicted value. Results The actual measured value of portal vein pressure before TIPS in 27 patients with portal hypertension was (3 783±930) Pa, and the predicted value was (4 238±1 218) Pa. There was no significant difference (P>0.05). The predicted value of portal venous pressure was positively correlated with the actual measured value (r=0.402, 95%CI: 0.026-0.678, P<0.05). Conclusion Non-invasive measurement of portal venous pressure based on three-dimensional portal venous reconstruction combined with finite element analysis correlated with actual portal venous pressure in patients with portal hypertension. Key words: Hypertension, portal; Imaging, three-dimensional; Multislice spiral computerized tomography; Correlation

Noninvasive Assessment of Portal Hypertension Using Spectral Computed Tomography.

Early diagnosis of portal hypertension is imperative for timely treatment to reduce the mortality rate. However, there is still no adequate method to noninvasively and accurately assess the portal hypertension in routine clinical practice. We aimed to evaluate the accuracy of parameters measured using dual energy spectral computed tomography (LightSpeed CT750 HD) in assessing portal venous pressure in patients with liver cirrhosis. Forty-five patients with liver cirrhosis who underwent percutaneous transhepatic portal vein puncture as part of their treatment for liver disease were enrolled in this study. Measurement of direct portal venous pressure was performed preoperatively. All patients underwent dual energy spectral computed tomography within 3 days before their operations. The iodine concentrations of portal vein and hepatic parenchyma during the portal venous phase and the alanine aminotransferase level were found to be independently correlated with the direct portal venous pressure according to stepwise multivariate linear regression analysis (P<0.001, 0.004, and 0.024, respectively). In a receiver operating characteristic analysis, the area under the receiver operating characteristic of iodine concentrations of the portal vein (ICPV) for identifying clinically significant portal hypertension (≥10 mm Hg) was significantly higher than that of iodine concentrations of hepatic parenchyma (ICliver) and the alanine aminotransferase level (0.944, 0.825, and 0.301, respectively). The threshold ICPV of 58.27 yielded a sensitivity of 93.8%, specificity of 69.2%, positive predictive value of 88.2%, and negative predictive value of 81.8%, respectively. ICPV values may be a useful tool in noninvasively assessing the portal venous pressure and identifying clinically significant portal hypertension in liver cirrhosis.

Influence of different lying positions on monitoring of central venous pressure in patients with mechanical ventilation: a systematic review

Objective To review systematically the influence of different lying positions on monitoring of central venous pressure (CVP) in patients with mechanical ventilation. Methods Relevant articles published publicly from database establishment date to June, 30th, 2018 in PubMed, Cochrane Library, Embase, Web of Science, CBM, Chinese Academic Journal Full-text Database (CJFD) , Wanfang and VIP Database were searched on computer. Two researchers independently screened and extracted the literature. RevMan 5.3 software was used for meta-analysis of the included studies. Results Nine literatures were included, including 380 subjects. Meta-analysis showed that there were significant statistical differences in CVP values between 30 degree semi-recumbent position and supine position (WMD=-0.70, 95%CI: -1.15--0.24, P=0.003) , and between 45 degree semi-recumbent position and supine position (WMD=-1.34, 95%CI: -1.82--0.86, P<0.001) , and between 60 degree semi-recumbent position and supine position (WMD=-2.96, 95%CI: -3.91--2.00, P<0.001) . Conclusions There are differences between the CVP measurements in the 30°, 45°, 60° hemi-recumbent position and the supine position. To ensure the accuracy of the CVP measurement values in mechanical ventilation patients, we should take the supine position for measurement. Key words: Central venous pressure; Lying position; Monitoring; Mechanical ventilation; Systematic review