INVASIVE HEMODYNAMIC MONITORING WITH PULMONARY ARTERY CATHETER IN SEPSIS-ASSOCIATED CARDIOGENIC SHOCK

ABSTRACT

Background: Both sepsis-induced cardiomyopathy and worsening of preexisting cardiac disease can contribute to circulatory shock in septic patients. The early use of pulmonary artery catheter (PAC) could play a pivotal role in the management of sepsis-associated cardiogenic shock. In this study, we aimed to evaluate the impact of early invasive hemodynamic monitoring with PAC in patients with sepsis-associated cardiogenic shock. Method: We performed a retrospective study using the National Inpatient Sample data from January 2017 to December 2019. The early use of PAC was defined as the use of PAC within 2 days from the admission. We performed the multivariable logistic regression analysis to investigate the association between the early use of PAC and in-hospital mortality in patients with sepsis-associated cardiogenic shock and sepsis without cardiogenic shock, respectively. Results: There was no difference in in-hospital mortality between PAC and no PAC groups in sepsis without cardiogenic shock (adjusted odds ratio [aOR] = 1.05, 95% confidence interval [CI] = 0.82-1.35, P = 691). On the other hand, the early use of PAC was independently associated with lower in-hospital mortality in patients with sepsis-associated cardiogenic shock (aOR = 0.58, 95% confidence interval [CI] = 0.46-0.72, P < 0.001). The use of PAC was also associated with increased use of mechanical circulatory support in those with sepsis-associated cardiogenic shock (aOR = 12.26, 95% CI = 9.37-16.03, P < 0.001). For patients with sepsis-associated cardiogenic shock, the use of PAC after 2 days of admission was associated with significantly higher in-hospital mortality and decreased use of mechanical circulatory support. Conclusion: The use of pulmonary artery catheters in sepsis-associated cardiogenic shock was associated with significantly lower in-hospital mortality and increased use of mechanical circulatory supports in patients with sepsis-associated cardiogenic shock.

Agreement between cardiac output estimation with a wireless, wearable pulse decomposition analysis device and continuous thermodilution in post cardiac surgery intensive care unit patients

PURPOSE

Pulse Decomposition Analysis (PDA) uses integration of the systolic area of a distally transmitted aortic pulse as well as arterial stiffness estimates to compute cardiac output. We sought to assess agreement of cardiac output (CO) estimation between continuous pulmonary artery catheter (PAC) guided thermodilution (CO-CCO) and a wireless, wearable noninvasive device, (Vitalstream, Caretaker Medical, Charlottesville, VA), that utilizes the Pulse Decomposition Analysis (CO-PDA) method in postoperative cardiac surgery patients in the intensive care unit.

METHODS

CO-CCO measurements were compared with post processed CO-PDA measurements in prospectively enrolled adult cardiac surgical intensive care unit patients. Uncalibrated CO-PDA values were compared for accuracy with CO-CCO via a Bland-Altman analysis considering repeated measurements and a concordance analysis with a 10% exclusion zone.

RESULTS

259.7 h of monitoring data from 41 patients matching 15,583 data points were analyzed. Mean CO-CCO was 5.55 L/min, while mean values for the CO-PDA were 5.73 L/min (mean of differences +- SD 0.79 ± 1.11 L/min; limits of agreement - 1.43 to 3.01 L/min), with a percentage error of 37.5%. CO-CCO correlation with CO-PDA was moderate (0.54) and concordance was 0.83.

CONCLUSION

Compared with the CO-CCO Swan-Ganz, cardiac output measurements obtained using the CO-PDA were not interchangeable when using a 30% threshold. These preliminary results were within the 45% limits for minimally invasive devices, and pending further robust trials, the CO-PDA offers a noninvasive, wireless solution to complement and extend hemodynamic monitoring within and outside the ICU.

Estimation of Right Atrial Pressure by Ultrasound-Assessed Jugular Vein Distensibility in Patients With Heart Failure

BACKGROUND

Clinical evaluation of central venous pressure is difficult, depends on experience, and is often inaccurate in patients with chronic advanced heart failure. We assessed the ultrasound-assessed internal jugular vein (JV) distensibility by ultrasound as a noninvasive tool to identify patients with normal right atrial pressure (RAP ≤7 mm Hg) in this population.

METHODS

We measured JV distensibility as the Valsalva-to-rest ratio of the vein diameter in a calibration cohort (N=100) and a validation cohort (N=101) of consecutive patients with chronic heart failure with reduced ejection fraction who underwent pulmonary artery catheterization for advanced heart failure therapies workup.

RESULTS

A JV distensibility threshold of 1.6 was identified as the most accurate to discriminate between patients with RAP ≤7 versus >7 mm Hg (area under the receiver operating characteristic curve, 0.74 [95% CI, 0.64-0.84]) and confirmed in the validation cohort (receiver operating characteristic, 0.82 [95% CI, 0.73-0.92]). A JV distensibility ratio >1.6 had predictive positive values of 0.86 and 0.94, respectively, to identify patients with RAP ≤7 mm Hg in the calibration and validation cohorts. Compared with patients from the calibration cohort with a high JV distensibility ratio (>1.6; n=42; median RAP, 4 mm Hg; pulmonary capillary wedge pressure, 11 mm Hg), those with a low JV distensibility ratio (≤1.6; n=58; median RAP, 8 mm Hg; pulmonary capillary wedge pressure, 22 mm Hg; P<0.0001 for both) were more likely to die or undergo a left ventricular assist device implant or heart transplantation (event rate at 2 years: 42.7% versus 18.2%; log-rank P=0.034).

CONCLUSIONS

Ultrasound-assessed JV distensibility identifies patients with chronic advanced heart failure with normal RAP and better outcomes.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03874312.

A classification system for pulmonary artery catheters

Flow-directed, balloon-tipped pulmonary artery catheters allow measuring cardiac output and other haemodynamic variables including intracardiac pressures. We propose classifying pulmonary artery catheters by generations and specifying additional measurement modalities. Based on the method used to measure cardiac output, pulmonary artery catheters can be classified into three generations: first-generation using intermittent pulmonary artery thermodilution; second-generation using a thermal filament for automated pulmonary artery thermodilution; and third-generation combining thermal filament-based automated pulmonary artery thermodilution and pulmonary artery pulse wave analysis. Each of these pulmonary artery catheter generations can include additional measurements, such as continuous mixed venous oxygen saturation, right ventricular ejection fraction and end-diastolic volume, and right ventricular pressure. This classification should help define indications for pulmonary artery catheters in clinical practice and research.

Characteristics of pulmonary artery catheter use in multicenter ICUs in Japan and the association with mortality: a multicenter cohort study using the Japanese Intensive care PAtient Database

BACKGROUND

It has been 50 years since the pulmonary artery catheter was introduced, but the actual use of pulmonary artery catheters in recent years is unknown. Some randomized controlled trials have reported no causality with mortality, but some observational studies have been published showing an association with mortality for patients with cardiogenic shock, and the association with a pulmonary artery catheter and mortality is unknown. The aim of this study was to investigate the utilization of pulmonary artery catheters (PACs) in the intensive care unit (ICU) and to examine their association with mortality, taking into account differences between hospitals.

METHODS

This is a retrospective analysis using the Japanese Intensive care PAtient Database, a multicenter, prospective, observational registry in Japanese ICUs. We included patients aged 16 years or older who were admitted to the ICU for reasons other than procedures. We excluded patients who were discharged within 24 h or had missing values. We compared the prognosis of patients with and without PAC. The primary outcome was hospital mortality. We performed propensity score analysis to adjust for baseline characteristics and hospital characteristics.

RESULTS

Among 184,705 patients in this registry from April 2015 to December 2020, 59,922 patients were included in the analysis. Most patients (94.0%) with a PAC in place had cardiovascular disease. There was a wide variation in the frequency of PAC use between hospitals, from 0 to 60.3% (median 14.4%, interquartile range 2.2-28.6%). Hospital mortality was not significantly different between the PAC use group and the non-PAC use group in patients after adjustment for propensity score analysis (3.9% vs 4.3%; difference, - 0.4%; 95% CI - 1.1 to 0.3; p = 0.32). Among patients with cardiac disease, those with post-open-heart surgery and those in shock, hospital mortality was also not significantly different between the two groups (3.4% vs 3.7%, p = 0.45, 1.7% vs 1.7%, p = 0.93, 4.8% vs 4.9%, p = 0.87).

CONCLUSIONS

The frequency of PAC use varied among hospitals. PAC use for ICU patients was not associated with lower hospital mortality after adjusting for differences between hospitals.

Toward Autonomous Pulmonary Artery Catheterization: A Learning-based Robotic Navigation System

Providing imaging during interventional treatments of cardiovascular diseases is challenging. Magnetic Resonance Imaging (MRI) has gained popularity as it is radiation-free and returns high resolution of soft tissue. However, the clinician has limited access to the patient, e.g., to their femoral artery, within the MRI scanner to accurately guide and manipulate an MR-compatible catheter. At the same time, communication will need to be maintained with a clinician, located in a separate control room, to provide the most appropriate image to the screen inside the MRI room. Hence, there is scope to explore the feasibility of how autonomous catheterization robots could support the steering of catheters along trajectories inside complex vessel anatomies.In this paper, we present a Learning from Demonstration based Gaussian Mixture Model for a robot trajectory optimisation during pulmonary artery catheterization. The optimisation algorithm is integrated into a 2 Degree-of-Freedom MR-compatible interventional robot allowing for continuous and simultaneous translation and rotation. Our methodology achieves autonomous navigation of the catheter tip from the inferior vena cava, through the right atrium and the right ventricle into the pulmonary artery where an interventions is performed. Our results show that our MR-compatible robot can follow an advancement trajectory generated by our Learning from Demonstration algorithm. Looking at the overall duration of the intervention, it can be concluded that procedures performed by the robot (teleoperated or autonomously) required significantly less time compared to manual hand-held procedures.

[Consensus on the operation of pulmonary artery catheterization]

Right heart catheterization(RHC) is a technique of inserting a catheter into the right heart and pulmonary artery via a peripheral vein, to evaluate hemodynamics and oxygen dynamics. When Swan-Ganz catheter is used, it is called pulmonary artery catheterization (PAC). PAC plays an important role in the diagnosis and evaluation of pulmonary hypertension (PH), and hemodynamic assessment of critically ill patients. We developed this consensus to improve the overall quality of RHC operation, especially the PAC standardization in the diagnosis and evaluation of PH, thereby to promote the diagnosis and treatment of PH in China.

Early pulmonary artery catheterization is not associated with survival benefits in critically ill patients with cardiac disease: An analysis of the MIMIC-IV database

BACKGROUND

Many studies demonstrated no improved survival in patients with pulmonary artery catheter placement. However, no consistent conclusions have been drawn regarding the impact of pulmonary artery catheter in critically ill patients with heart disease. This study aimed to investigate the association of early pulmonary artery catheter use with 28-day mortality in that population.

METHODS

The Multiparameter Intelligent Monitoring in Intensive Care IV (MIMIC-IV) database, a single-center critical care database, was employed to investigate this issue. This study enrolled a total of 11,887 critically ill patients with cardiac disease with or without pulmonary artery catheter insertion. The primary outcome was 28-day mortality. The multivariate regression was modeled to examine the association between pulmonary artery catheter and outcomes. Additionally, we examined the effect modification by cardiac surgeries. Propensity score matching was conducted to validate our findings.

RESULTS

No improvement in 28-day mortality was observed among the pulmonary artery catheter group compared to the non-pulmonary artery catheter group (odds ratio 95% confidence interval: 1.18 [1.00-1.38], P = .049). When stratified by cardiac surgeries, the results were consistent. The patients in the pulmonary artery catheter group had fewer ventilation-free days and vasopressor-free days than those in the nonpulmonary artery catheter group after surgery stratification. In the surgical patients, pulmonary artery catheter insertion was not associated with the occurrence of acute kidney injury, and it was associated with a higher daily fluid input (mean difference 95% confidence interval: 0.13 [0.05-0.20], P = .001). In nonsurgical patients, the pulmonary artery catheter group had a higher risk of acute kidney injury occurrence (odds ratio 95% confidence interval: 1.94 [1.32-2.84], P = .001).

CONCLUSION

Early pulmonary artery catheter placement is not associated with survival benefits in critically ill patients with cardiac diseases, either in surgical or nonsurgical patients.

Systemic arterial pulsatility index (SAPi) predicts adverse outcomes in advanced heart failure patients

Ventriculo-arterial (VA) coupling has been shown to have physiologic importance in heart failure (HF). We hypothesized that the systemic arterial pulsatility index (SAPi), a measure that integrates pulse pressure and a proxy for left ventricular end-diastolic pressure, would be associated with adverse outcomes in advanced HF. We evaluated the SAPi ([systemic systolic blood pressure-systemic diastolic blood pressure]/pulmonary artery wedge pressure) obtained from the final hemodynamic measurement in patients randomized to therapy guided by a pulmonary arterial catheter (PAC) and with complete data in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial. Cox proportional hazards regression was performed for the outcomes of (a) death, transplant, left ventricular assist device (DTxLVAD) or hospitalization, (DTxLVADHF) and (b) DTxLVAD. Among 142 patients (mean age 56.8 ± 13.3 years, 30.3% female), the median SAPi was 2.57 (IQR 1.63-3.45). Increasing SAPi was associated with significant reductions in DTxLVAD (HR 0.60 per unit increase in SAPi, 95% CI 0.44-0.84) and DTxLVADHF (HR 0.81 per unit increase, 95% CI 0.70-0.95). Patients with a SAPi ≤ 2.57 had a marked increase in both outcomes, including more than twice the risk of DTxLVAD (HR 2.19, 95% CI 1.11-4.30) over 6 months. Among advanced heart failure patients with invasive hemodynamic monitoring in the ESCAPE trial, SAPi was strongly associated with adverse clinical outcomes. These findings support further investigation of the SAPi to guide treatment and prognosis in HF undergoing invasive hemodynamic monitoring.

Preliminary experience with continuous right ventricular pressure and transesophageal echocardiography monitoring in orthotopic liver transplantation

Background

Despite increasing attention in the cardiac anesthesiology literature, continuous measurement of right ventricular pressure using a pulmonary artery catheter has not been described in orthotopic liver transplantation, despite similarities in the anesthetic approach to the two populations. We describe our preliminary experience with this technique in orthotopic liver transplantation, and by combining various derived measures with trans-esophageal echocardiography, make some early observations regarding the response of these measures of right ventricular function during the procedure.

Methods

In this case series, ten patients (five men and five women) undergoing orthotopic liver transplantation in our institution had their surgeries performed while monitored with a pulmonary artery catheter with continuous right ventricular port transduction and trans-esophageal echocardiography. We recorded various right ventricular waveform (early-to-end diastolic pressure difference, right ventricular outflow tract gradient, right ventricular dP/dT and right ventricular end-diastolic pressure) and echocardiographic (right ventricular fractional area change, tricuspid annular plane systolic excursion, right ventricular lateral wall strain) and described their change relative to baseline at timepoints five minutes before and after portal vein reperfusion, immediately after hepatic artery reperfusion and on abdominal closure.

Results

Except for tricuspid annular plane systolic excursion at five minutes prior to reperfusion (mean −0.8 cm; 95% CI−1.4, –0.3; p = 0.007), no echocardiographic metric was statistically significantly different at any timepoint relative to baseline. In contrast, changes in right ventricular outflow tract gradient and right ventricular dP/dt were highly significant at multiple timepoints, generally peaking immediately before or after reperfusion before reducing, but not returning to baseline in the neohepatic phase. Nine of 10 participants in this series demonstrated a degree of dynamic right ventricular outflow tract obstruction, which met criteria for hemodynamic significance (> 25 mmHg) in two participants. These changes were not materially affected by cardiac index.

Conclusions

Dynamic right ventricular outflow tract obstruction of varying severity appears common in patients undergoing orthotopic liver transplantation. These results are hypothesis generating and will form the basis of future prospective research.

CT-guided transthoracic pulmonary artery catheterization: an experimental study in a porcine model

OBJECTIVES

We investigated the safety and feasibility of CT-guided transthoracic pulmonary artery catheterization (TPAC) in a porcine model.

METHODS

Procedures were conducted on ten mature Bama miniature pigs. After anesthesia, chest CT was performed in the left lateral decubitus position to determine the puncture route. Under the guidance of multiple CT scans, the introducer sheath was inserted from the right chest wall of the pig into the right pulmonary artery using the Seldinger technique. Then, a catheter connected with a transducer was inserted into the sheath to measure the pulmonary artery pressure. Finally, an active approximator was used to close the puncture site on the pulmonary artery. The pigs were followed up for 8 weeks to evaluate the operation-related complications and survival.

RESULTS

Ten of 11 CT-guided TPAC procedures were successfully performed on ten pigs, rendering a technical success rate of 90.9%. One pig had hemoptysis while the needle was being inserted during the first operation, and a second procedure was successfully conducted 17 days later. Other complications, including pulmonary bleeding along the needle track (3 of 11; 27.3%), unclosed pulmonary artery puncture sites (3 of 10; 30%), pneumothorax (1 of 11; 9.1%), and hemopericardium (1 of 11; 9.1%), spontaneously resolved without complication-specific treatment. The mean pulmonary arterial pressure was 32 ± 17.6 mmHg. All animals survived the procedure and reached the end of the follow-up period.

CONCLUSIONS

CT-guided TPAC is feasible and safe in a porcine model, serving as a potential alternative pathway for pulmonary artery intervention.

KEY POINTS

• TPAC is feasible and safe in a porcine model, serving as a potential alternative pathway for pulmonary artery intervention. • This novel approach allows for faster access to the pulmonary artery, and it might be easier to operate the tip of the catheter to super-select the intent branch of the pulmonary artery. • TPAC can be an alternative pulmonary artery intervention pathway in patients with mechanical right-heart valves, great-vessel transposition, and other obstacles.

A Tale of Two Pulmonary Artery Catheters

Innovative catheter-based therapies are increasingly being used for the treatment of patients with submassive pulmonary embolism. These patients may be monitored in the intensive care unit following insertion of specialized pulmonary artery catheters. However, the infusion catheters utilized in catheter-based therapies differ greatly from traditional pulmonary artery catheters designed for hemodynamic monitoring. As such, the critical care team will have to be familiar with the monitoring and management of these novel catheters. Important distinctions between the catheters are illustrated using a clinical case report.

Incremental Experience in In Vitro Primary Culture of Human Pulmonary Arterial Endothelial Cells Harvested from Swan-Ganz Pulmonary Arterial Catheters

Pulmonary arterial hypertension (PAH) is a devastating condition affecting the pulmonary microvascular wall and endothelium, resulting in their partial or total obstruction. Despite a combination of expensive vasodilatory therapies, mortality remains high. Personalized therapeutic approaches, based on access to patient material to unravel patient specificities, could move the field forward. An innovative technique involving harvesting pulmonary arterial endothelial cells (PAECs) at the time of diagnosis was recently described. The aim of the present study was to fine-tune the initial technique and to phenotype the evolution of PAECs in vitro subcultures. PAECs were harvested from Swan-Ganz pulmonary arterial catheters during routine diagnostic or follow up right heart catheterization. Collected PAECs were phenotyped by flow cytometry and immunofluorescence focusing on endothelial-specific markers. We highlight the ability to harvest patients’ PAECs and to maintain them for up to 7–12 subcultures. By tracking the endothelial phenotype, we observed that PAECs could maintain an endothelial phenotype for several weeks in culture. The present study highlights the unique opportunity to obtain homogeneous subcultures of primary PAECs from patients at diagnosis and follow-up. In addition, it opens promising perspectives regarding tailored precision medicine for patients suffering from rare pulmonary vascular diseases.

Pulmonary artery catheterization in patients with cardiogenic shock: a systematic review and meta-analysis

PURPOSE

Cardiogenic shock carries high morbidity and mortality. The purpose of this review was to determine the safety and efficacy of pulmonary artery catheterization (PAC) in adult patients hospitalized with cardiogenic shock.

SOURCE

We performed a systematic review and meta-analysis of observational studies and randomized controlled trials comparing PAC vs no PAC in cardiogenic shock. We searched MEDLINE, EMBASE, Cochrane CENTRAL, and grey literature. We screened articles, abstracted data, and evaluated risk of bias in duplicate. We pooled data using a random-effects model and evaluated the quality of evidence using the GRADE framework. Outcomes of interest were mortality, length of stay, and procedural complications.

PRINCIPAL FINDINGS

We identified 19 eligible observational studies (≥ 2,716,287 patients) and no randomized controlled trials; 14 studies were at high risk of bias (lack of adjustment for prognostic variables and/or co-interventions). When pooling adjusted results, PAC was associated with improved survival to hospital discharge (relative risk [RR], 0.77; 95% confidence interval [CI], 0.64 to 0.91, I2 = 98%; very low-quality evidence) and at longest available follow-up (RR, 0.72; 95% CI, 0.60 to 0.87; I2 = 99%; very low-quality evidence). Unadjusted length of stay was 3.5 days longer (95% CI, 1.49 to 5.54; I2 = 100%; very low-quality evidence) with PAC. Procedural complications were inconsistently reported.

CONCLUSIONS

Very low-quality observational evidence suggests PAC use in patients with cardiogenic shock is associated with lower mortality. Overall, these results support consideration of PAC for hemodynamic assessment in cardiogenic shock. Prospective randomized clinical trials are needed to further characterize the role of PAC in this population.

Aortic pulsatility index predicts clinical outcomes in heart failure: a sub-analysis of the ESCAPE trial

AIMS

Aortic pulsatility index (API), calculated as (systolic-diastolic blood pressure)/pulmonary capillary wedge pressure (PCWP), is a novel haemodynamic measurement representing both cardiac filling pressures and contractility. We hypothesized that API would better predict clinical outcomes than traditional haemodynamic metrics of cardiac function.

METHODS AND RESULTS

The Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial individual-level data were used. Routine haemodynamic measurements, including Fick cardiac index (CI), and the advanced haemodynamic metrics of API, cardiac power output (CPO), and pulmonary artery pulsatility index (PAPI) were calculated after final haemodynamic-monitored optimization. The primary outcome was a composite endpoint of death or need for orthotopic heart transplant (OHT) or left ventricular assist device (LVAD) at 6 months. A total of 433 participants were enrolled in the ESCAPE trial of which 145 had final haemodynamic data. Final API measurements predicted the primary outcome, OR 0.47 (95% CI 0.32-0.70, P < 0.001), while CI, CPO, and PAPI did not. Receiver operator characteristic analyses of final advanced haemodynamic measurements indicated API best predicted the primary outcome with a cutoff of 2.9 (sensitivity 76.2%, specificity 55.3%, correctly classified 61.4%, area-under-the-curve 0.71), compared with CPO, CI, and PAPI. Kaplan-Meier analyses indicated API ≥ 2.9 was associated with greater freedom from the primary outcome (83.5%), compared with API < 2.9 (58.4%), P = 0.001. While PAPI was also significantly associated, CI and CPO were not.

CONCLUSIONS

The novel haemodynamic measurement API better predicted clinical outcomes in the ESCAPE trial when compared with traditional invasive haemodynamic metrics of cardiac function.

[Pulmonary Artery Catheter-induced Massive Tracheal Hemorrhage during Aortic Valve Surgery;Report of a Case]

We report a case of pulmonary artery catheter (PAC)-induced massive intratracheal hemorrhage during aortic valve surgery. An 81-year-old woman underwent aortic valve replacement and pulmonary vein isolation. Operative procedures were uneventful, but active and massive intratracheal hemorrhage started just after cardiopulmonary bypass was discontinued. We immediately resumed cardiopulmonary bypass and replaced the endotracheal tube with a double-lumen one, keeping the airway pressure high (20 cmH2O). Those maneuvers reduced intratracheal hemorrhage and maintained oxygenation, and then cardiopulmonary bypass was disconnected without lung lobectomy. Mechanical ventilation with high positive end expiratory pressure for 6 days in the intensive care unit let her good recovery. A postoperative enhanced computed tomography revealed a thrombosed right pulmonary artery pseudoaneurysm possibly induced by PAC. After close observation the patient left the hospital on foot.

Comparison Between Swan-Ganz Catheter and Minimally Invasive Hemodynamic Monitoring During Liver Transplantation: Report of a Monocentric Case Series

INTRODUCTION

The aim of the present investigation was to retrospectively evaluate the utilization of Swan-Ganz catheter during orthotopic liver transplantation as opposed to FloTrac/Vigileo in selected cases, comparing a number of clinical outcomes across postoperative hospitalization.

MATERIALS AND METHODS

Before 2015 all recipients received pulmonary artery catheter (Swan-Ganz group, n = 109). After 2015 Swan-Ganz was used only if coronary artery disease or high-grade portal hypertension or Child-Pugh C were present; the remaining recipients were assigned to FloTrac/Vigileo monitoring (Mini group, n =100). A number of clinical outcomes were considered.

RESULTS

Donor's Risk Index was similar between groups (median value 1.7, P = .27). Anthropometric characteristics of the recipients were similar in the 2 groups. There were no significant differences in the proportion of patients with Child-Pugh C (P = .873), coronary artery disease (P = .18), and grade of portal hypertension (P = .733). The Model for End-Stage Liver Disease score was slightly higher in the Mini group: (9 [7-11] vs 9 [8-12], Swan-Ganz vs Mini, respectively, P < .035). Swan-Ganz utilization decreased over time (92% vs 26%, Swan-Ganz vs Mini, P < .001). Upon admission to the intensive care unit, patients of the Mini group presented a higher SAPS II score with similar values of Sequential Organ Failure Assessment score. Days on mechanical ventilation were similar between groups. The incidence of graft failure was similar between groups (2% vs 5%, Swan-Ganz and Mini group respectively, P = .376). Recipients' hospital length of stay was similar (13 days [11-19] vs 14 [11-20], P < .083).

CONCLUSIONS

Our data suggest that the intraoperative utilization of FloTrac/Vigileo for oncologic patients with low grade end stage liver disease is reasonably safe.

Impact of pulmonary endarterectomy on pulmonary arterial wave propagation and reservoir function

High wave speed and large wave reflection in the pulmonary artery have previously been reported in patients with chronic thromboembolic pulmonary hypertension (CTEPH). We assessed the impact of pulmonary endarterectomy (PEA) on pulmonary arterial wave propagation and reservoir function in patients with CTEPH. Right heart catheterization was performed using a combined pressure and Doppler flow sensor-tipped guidewire to obtain simultaneous pressure and flow velocity measurements in the pulmonary artery in eight patients with CTEPH before and 3 mo after PEA. Wave intensity and reservoir-excess pressure analyses were then performed. Following PEA, mean pulmonary arterial pressure (PAPm; ∼49 vs. ∼32 mmHg), pulmonary vascular resistance (PVR; ∼11.1 vs. ∼5.1 Wood units), and wave speed (∼16.5 vs. ∼8.1 m/s), i.e., local arterial stiffness, markedly decreased. The changes in the intensity of the reflected arterial wave and wave reflection index (pre: ∼28%; post: ∼22%) were small, and patients post-PEA with and without residual pulmonary hypertension (i.e., PAPm ≥ 25 mmHg) had similar wave reflection index (∼20 vs. ∼23%). The reservoir and excess pressure decreased post-PEA, and the changes were associated with improved right ventricular afterload, function, and size. In conclusion, although PVR and arterial stiffness decreased substantially following PEA, large wave reflection persisted, even in patients without residual pulmonary hypertension, indicating lack of improvement in vascular impedance mismatch. This may continue to affect the optimal ventriculoarterial interaction, and further studies are warranted to determine whether this contributes to persistent symptoms in some patients.NEW & NOTEWORTHY We performed wave intensity analysis in the pulmonary artery in patients with chronic thromboembolic pulmonary hypertension before and 3 mo after pulmonary endarterectomy. Despite substantial reduction in pulmonary arterial pressures, vascular resistance, and arterial stiffness, large pulmonary arterial wave reflection persisted 3 mo postsurgery, even in patients without residual pulmonary hypertension, suggestive of lack of improvement in vascular impedance mismatch.

[Latest Monitoring Systems for Vital Signs in Cardiothoracic Surgery]

In this review article, the latest monitoring systems for vital signs in cardiothoracic surgery, including a multi-wavelength pulse oximeter, a transcutaneous blood gas monitoring system, a modified pulmonary artery catheter, and modern less-invasive cardiac output measurement systems are introduced. These less-invasive and real-time/continuous monitoring technologies would provide useful information for perioperative care after cardiothoracic surgeries, and improve the outcomes of surgeries.

Cardiac output measurement in liver transplantation patients using pulmonary and transpulmonary thermodilution: a comparative study

During liver transplantation surgery, the pulmonary artery catheter-despite its invasiveness-remains the gold standard for measuring cardiac output. However, the new EV1000 transpulmonary thermodilution calibration technique was recently introduced into the market by Edwards LifeSciences. We designed a single-center prospective observational study to determine if these two techniques for measuring cardiac output are interchangeable in this group of patients. Patients were monitored with both pulmonary artery catheter and the EV1000 system. Simultaneous intermittent cardiac output measurements were collected at predefined steps: after induction of anesthesia (T1), during the anhepatic phase (T2), after liver reperfusion (T3), and at the end of the surgery (T4). The 4-quadrant and polar plot techniques were used to assess trending ability between the two methods. We enrolled 49 patients who underwent orthotopic liver transplantation surgery. We analyzed a total of 588 paired measurements. The mean bias between pulmonary artery catheter and the EV1000 system was 0.35 L/min with 95% limits of agreement of - 2.30 to 3.01 L/min, and an overall percentage error of 35%. The concordance rate between the two techniques in 4-quadrant plot analysis was 65% overall. The concordance rate of the polar plot showed an overall value of 83% for all pairs. In the present study, in liver transplantation patients we found that intermittent cardiac output monitoring with EV1000 system showed a percentage error compared with pulmonary artery catheter in the acceptable threshold of 45%. On the others hand, our results showed a questionable trending ability between the two techniques.

Pulmonary Catherization Data Correlate Poorly with Renal Function in Heart Failure

BACKGROUND

The mechanisms of renal dysfunction in heart failure are poorly understood. We chose to explore the relationship of cardiac filling pressures and cardiac index (CI) in relation to renal dysfunction in advanced heart failure.

OBJECTIVES

To determine the relationship between renal function and cardiac filling pressures using the United Network of Organ Sharing (UNOS) pulmonary artery catherization registry.

METHODS

Patients over the age of 18 years who were listed for single-organ heart transplantation were included. Exclusion criteria included a history of mechanical circulatory support, previous transplantation, any use of renal replacement therapy, prior history of malignancy, and cardiac surgery, amongst others. Correlations between serum creatinine (SCr) and CI, pulmonary capillary wedge pressure (PCWP), pulmonary artery systolic pressure (PASP), and pulmonary artery diastolic pressure (PADP) were assessed by Pearson correlation coefficients and simple linear regression coefficients.

RESULTS

Pearson correlation coefficients between SCr and PCWP, PASP, and PADP were near zero with values of 0.1, 0.07, and 0.08, respectively (p < 0.0001). A weak negative correlation coefficient between SCr and CI was found (correlation coefficient, -0.045, p = 0.027). In a subgroup of young patients unlikely to have noncardiac etiologies, no significant correlations between these values were identified.

CONCLUSION

These findings suggest that, as assessed by pulmonary artery catherization, none of the factors - PCWP, PASP, PADP, or CI - play a prominent role in cardiorenal syndromes.

Transoesophageal echocardiography during orthotopic liver transplantation

Despite the importance of haemodynamic management in patients undergoing liver transplantation, there is currently no consensus on the most appropriate type of monitoring to use. In this context, transoesophageal echocardiography can provide useful information to professionals, although their use constraints prevent further spread today.

[Chronic Kidney Disease;Tips and Pitfall of Perioperative Management]

Chronic kidney disease(CKD) is an important risk factor of open heart surgery. In addition, worsening of kidney function after the surgery leads to poor prognosis long-term. It is therefore crucial to protect the kidney function by intensive perioperative management in open heart surgery. In the patients having stage 3-4 CKD, mean arterial pressure needs to be higher than 70 mmHg and cardiac index needs to be greater than 2.4 intraoperatively and postoperatively. Continuous right heart monitoring by Swan-Ganz catheter is useful for this purpose. In the patients having stage 5 CKD, systemic complications need to be thoroughly evaluated preoperatively. Hemodialysis and serum potassium control during the extracorporeal circulation is important to minimize delay of postoperatively recovery. For coronary artery bypass grafting, off-pump approach would be a good option in stage 3-4 and stage 5 CKD patients.

Percutaneous Valvuloplasty for Bioprosthetic Tricuspid Valve Stenosis

Percutaneous transcatheter tricuspid balloon valvuloplasty (PTTBV) is an accepted treatment option for symptomatic severe native tricuspid valve stenosis, although surgical tricuspid valve replacement remains the treatment of choice. There have been few reports of successful PTTBV for bioprosthetic tricuspid valve stenosis. We present case reports of 3 patients from our hospital experience. Two of the 3 cases were successful, with lasting clinical improvement, whereas the 3rd patient failed to show a reduction in valve gradient. We describe the standard technique used for PTTBV. We present results from a literature review that identified 16 previously reported cases of PTTBV for bioprosthetic severe tricuspid stenosis, with overall favorable results. We conclude that PTTBV should perhaps be considered for a select patient population in which symptomatic improvement and hemodynamic stability are desired immediately, and particularly for patients who are inoperable or at high surgical risk.

Pilot Study: Estimation of Stroke Volume and Cardiac Output from Pulse Wave Velocity

Background

Transesophageal echocardiography (TEE) is increasingly replacing thermodilution pulmonary artery catheters to assess hemodynamics in patients at high risk for cardiovascular morbidity. However, one of the drawbacks of TEE compared to pulmonary artery catheters is the inability to measure real time stroke volume (SV) and cardiac output (CO) continuously. The aim of the present proof of concept study was to validate a novel method of SV estimation, based on pulse wave velocity (PWV) in patients undergoing cardiac surgery.

Methods

This is a retrospective observational study. We measured pulse transit time by superimposing the radial arterial waveform onto the continuous wave Doppler waveform of the left ventricular outflow tract, and calculated SV (SV_PWV) using the transformed Bramwell-Hill equation. The SV measured by TEE (SV_TEE) was used as a reference.

Results

A total of 190 paired SV were measured from 28 patients. A strong correlation was observed between SV_PWV and SV_TEE with the coefficient of determination (R²) of 0.71. A mean difference between the two (bias) was 3.70 ml with the limits of agreement ranging from -20.33 to 27.73 ml and a percentage error of 27.4% based on a Bland-Altman analysis. The concordance rate of two methods was 85.0% based on a four-quadrant plot. The angular concordance rate was 85.9% with radial limits of agreement (the radial sector that contained 95% of the data points) of ± 41.5 degrees based on a polar plot.

Conclusions

PWV based SV estimation yields reasonable agreement with SV measured by TEE. Further studies are required to assess its utility in different clinical situations.

Evaluation of New Calibrated Pulse-Wave Analysis (VolumeViewTM/EV1000TM) for Cardiac Output Monitoring Undergoing Living Donor Liver Transplantation

Background

Intrapulmonary thermodilution technique using a pulmonary artery catheter is widely used for measuring cardiac output (CO) in patients undergoing liver transplantation. However, its invasiveness and associated complications have led to an interest in less invasive modalities. Thus, we aimed to evaluate whether the new calibrated pulse-wave analysis method monitoring (VolumeView^TM/EV1000^TM) is interchangeable with intrapulmonary thermodilution technique.

Methods

Twenty-eight patients undergoing living donor liver transplantation were enrolled in this prospective observational study. COs were recorded automatically by the two devices and compared simultaneously at 10-minute intervals. The agreement of absolute CO values and the tracking ability of CO changes trends were compared. A Bland-Altman analysis with percentage errors and concordance rate for trend analysis using both a 4-quadrant plot and a polar plot were performed on the data.

Results

A total of 375 paired datasets from 25 patients were included in analysis. COs measured by intrapulmonary thermodilution ranged from 3.8–13.7 L/min. The mean CO difference between the two techniques was 0.57 L/min, and the 95% limits of agreement were -0.98 L/min to 2.12 L/min with a percentage error of 42.3%. The percentage errors in the dissection, anhepatic, and reperfusion phase were 30.5%, 31.7%, and 27.4%, respectively. The concordance rate between the two techniques was 78.4%.

Conclusion

The calibrated pulse-wave analysis and intrapulmonary thermodilution failed to show acceptable interchangeability in terms of both estimating CO and tracking CO changes during living donor liver transplantation.

[Pulmonary Artery Catheter Injured by Ablation Device during Maze Procedure]

We report a case of pulmonary artery catheter (PAC) injury by radio frequency device for maze procedure. A 64-year-old female with severe mitral insufficiency, tricuspid insufficiency and paroxysmal atrial fibrillation was scheduled for mitral valve repair, tricuspid annulo- plasty and maze procedure including right-sided maze. Under general anesthesia, a PAC was inserted to pul- monary artery (PA) uneventfully. After radio frequency maze procedure and mitral valve repair, PAC was removed from right atrium by the surgeon for tricus- pid annuloplasty. Thereafter, the surgeon reinserted the PAC under transesophageal echocardiographic guidance since PAC balloon could not be inflated. PA pressure and cardiac output were not shown despite other parameters were correct We removed the PAC and reinserted a new one after the surgery. The PAC was compressed at about 25 cm from the tip and it appears to have been injured during right-sided maze procedure with radio frequency device. Complications of PAC are well known, including PA rupture and suture entrapment to the right atrium. To best of our knowledge, this is the first reported case of PAC injury by radio frequency device. Fortunately the PAC was not torn in our case ; however, there might have been a risk of infection through the thermodilu- tion cable.

How to Reliably Detect Ischemia in the Intensive Care Unit and Operating Room

Detection of myocardial ischemia in the perioperative period is important because it allows for intervention that may prevent progression of ischemia to myocardial infarction. Perioperative ischemia is also an important predictor of adverse cardiovascular outcomes. Patients should first be stratified according to their risk of having cardiovascular disease by identifying major, intermediate, and minor predictors of adverse cardiovascular outcome. Electrocardiographic (ECG) monitoring for ischemia is inexpensive and noninvasive, but may not be applicable to all patients and is not perfectly sensitive or specific. Modern operating room monitors can automate ST segment monitoring and be set to alarm if changes occur. Increases in central venous pressure and pulmonary artery pressure can be caused by myocardial ischemia, but have been shown to be very insensitive compared to ECG. Also, detection of these hemodynamic changes requires insertion of invasive monitoring devices. Transesophageal echocardiography can be used to detect myocardial ischemia by identifying changes in regional wall motion. These transesophageal echocardiography changes occur sooner and more frequently than ECG changes, but require greater knowledge and skill to properly interpret.

Anaesthesiological strategies to improve outcome in liver transplantation recipients

Graft and patients survival are the main goal of anesthesiological management in patients undergoing liver transplantation (LT). Even if anesthesiological practice sustained major developments over time, some evidence-based intraoperative strategies have not yet been widely applied. The aim of this review was to summarize intraoperative anesthesiological strategies which could have the potential to improve LT graft and/or recipient survival. Monitoring must be as accurate as possible in order to manage intraoperative hemodynamic changes. The pulmonary artery catheter still represents the more reliable method to monitor cardiac output by using the intermittent bolus thermodilution technique. Minimally invasive hemodynamic monitoring devices may be considered only in stable cirrhotic patients. Goal-directed fluid-therapy has not yet defined for LT, but it could have a role in optimizing the long-term sequelae associated with volume depletion or overload. The use of vasopressor may affect LT recipient's outcome, by preventing prolonged hypotension, decreasing blood products transfusion and counteracting hepato-renal syndrome. The use of viscoelastic point of care is also warranted in order to reduce blood products requirements. Decreasing mechanical ventilation time, when it is feasible, may considerably improve survival. Finally, monitoring the depth of anesthesia when integrated into an early extubation protocol might have a positive effect on graft function.

Zero-Heat-Flux Thermometry for Non-Invasive Measurement of Core Body Temperature in Pigs

Hypothermia is a severe, unpleasant side effect during general anesthesia. Thus, temperature surveillance is a prerequisite in general anesthesia settings during experimental surgeries. The gold standard to measure the core body temperature (T_core) is placement of a Swan-Ganz catheter in the pulmonary artery, which is a highly invasive procedure. Therefore, T_core is commonly examined in the urine bladder and rectum. However, these procedures are known for their inaccuracy and delayed record of temperatures. Zero-heat-flux (ZHF) thermometry is an alternative, non-invasive method quantifying T_core in human patients by applying a thermosensoric patch to the lateral forehead. Since the porcine cranial anatomy is different to the human’s, the optimal location of the patch remains unclear to date. The aim was to compare three different patch locations of ZHF thermometry in a porcine hypothermia model. Hypothermia (33.0°C T_core) was conducted in 11 anesthetized female pigs (26-30kg). T_core was measured continuously by an invasive Swan-Ganz catheter in the pulmonary artery (T_pulm). A ZHF thermometry device was mounted on three different defined locations. The smallest average difference between T_pulm and T_ZHF during stable temperatures was 0.21 ± 0.16°C at location A, where the patch was placed directly behind the eye. Also during rapidly changing temperatures location A showed the smallest bias with 0.48 ± 0.29°C. Location A provided the most reliable data for T_core. Therefore, the ZHF thermometry patch should be placed directly behind the left temporal corner of the eye to provide a non-invasive method for accurate measurement of T_core in pigs.

Clinical Implications of Cluster Analysis-Based Classification of Acute Decompensated Heart Failure and Correlation with Bedside Hemodynamic Profiles

Background

Classification of acute decompensated heart failure (ADHF) is based on subjective criteria that crudely capture disease heterogeneity. Improved phenotyping of the syndrome may help improve therapeutic strategies.

Objective

To derive cluster analysis-based groupings for patients hospitalized with ADHF, and compare their prognostic performance to hemodynamic classifications derived at the bedside.

Methods

We performed a cluster analysis on baseline clinical variables and PAC measurements of 172 ADHF patients from the ESCAPE trial. Employing regression techniques, we examined associations between clusters and clinically determined hemodynamic profiles (warm/cold/wet/dry). We assessed association with clinical outcomes using Cox proportional hazards models. Likelihood ratio tests were used to compare the prognostic value of cluster data to that of hemodynamic data.

Results

We identified four advanced HF clusters: 1) male Caucasians with ischemic cardiomyopathy, multiple comorbidities, lowest B-type natriuretic peptide (BNP) levels; 2) females with non-ischemic cardiomyopathy, few comorbidities, most favorable hemodynamics; 3) young African American males with non-ischemic cardiomyopathy, most adverse hemodynamics, advanced disease; and 4) older Caucasians with ischemic cardiomyopathy, concomitant renal insufficiency, highest BNP levels. There was no association between clusters and bedside-derived hemodynamic profiles (p = 0.70). For all adverse clinical outcomes, Cluster 4 had the highest risk, and Cluster 2, the lowest. Compared to Cluster 4, Clusters 1–3 had 45–70% lower risk of all-cause mortality. Clusters were significantly associated with clinical outcomes, whereas hemodynamic profiles were not.

Conclusions

By clustering patients with similar objective variables, we identified four clinically relevant phenotypes of ADHF patients, with no discernable relationship to hemodynamic profiles, but distinct associations with adverse outcomes. Our analysis suggests that ADHF classification using simultaneous considerations of etiology, comorbid conditions, and biomarker levels, may be superior to bedside classifications.

Chronic Thromboembolic Pulmonary Hypertension: Experience from a Single Center in Mexico

INTRODUCTION

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by precapillary pulmonary hypertension secondary to vaso-occlusive pulmonary vasculopathy and is classified as Pulmonary Hypertension Group 4. The aim of this study is to report the clinical experience of CTEPH in Mexico.

METHODS

Consecutive patients diagnosed with CTEPH were identified from the Registro de Pacientes con Hipertension Pulmonar del Instituto de Seguridad y Servicio Social de los Trabajadores del Estado (REPHPISSSTE) registry between January 2009 and February 2014. Right heart catheterization was not routinely performed prior to August 2010 in the work-up of CTEPH.

RESULTS

We identified 50 patients with CTEPH; their median age was 63 years and 58 % were female. Patients had multiple associated co-morbidities and moderate hemodynamic impairment. All patients were treated with anticoagulation. Despite surgical evaluation for pulmonary endarterectomy (PEA), only one patient underwent PEA given the lack of infrastructure for post-operative care and lack of insurance for this procedure. Most of the patients were treated with sildenafil, bosentan, or both, with increasing use of rivaroxaban and sildenafil in recent years. The overall survival of the cohort was similar to that reported in other international registries, despite the limitations of care imposed by drug availability and surgical feasibility.

CONCLUSION

This is the first report on the CTEPH experience in Mexico. It highlights the similarity of patients in the REPHPISSSTE registry to those in international registries as well as the challenges that clinicians face in a resource-limited setting.

[The application of peripartum use of pulmonary artery catheter in pregnant patients with pulmonary hypertension]

OBJECTIVE

To investigate the application and value of pulmonary artery catheterization (PAC) in pregnant patients with pulmonary hypertension (PH).

METHODS

The clinical data of pregnant patients with PH who were treated between 2006 and 2014 in surgical intensive care unit (SICU) at Capital Medical University affiliated Beijing Anzhen Hospital were retrospectively analysed. The differences of the clinical characteristics and outcome between PAC inserted patients and PAC not inserted patients were compared.

RESULTS

The systolic pulmonary artery pressure (sPAP) measured by preoperative echocardiography has no significant difference between the PAC inserted patients [(103.0 ± 24.1) mmHg (1 mmHg = 0.133 kPa)] and PAC not inserted patients [(96.4 ± 27.3) mmHg; P = 0.175]. SPAP may be overestimated or underestimated by echocardiography compared with PAC with a gap from -38.4 mmHg to 49.5 mmHg. The rates of idiopathic pulmonary arterial hypertension (20.0% vs 3.2%) and continuous use of epidural anesthesia (89.1% vs 65.1%) were higher in PAC inserted patients compared with PAC not inserted patients. Norepinephrine, dobutamine, sildenafil, alprostadil, iloprost and low molecular weight heparin were more widely used in PAC inserted patients. The mortality rate and the rates of low birth weight (63.9% vs 30.6%) and very low birth weight infants (19.4% vs 13.9%) were all higher in PAC inserted patients, while the rate of induced abortion was lower in this group (5.5% vs 17.5%). The length of stay in surgical intensive care unit [6.0 (5.0) d vs 1.0 (3.0) d], postoperative length of stay [8.0 (6.0) d vs 8.0 (4.0) d] and total hospital costs [43 999.22 (38 267.27) RMB vs 14 878.24 (10 564.47) RMB] were all higher in PAC inserted patients. The incidence rate of PAC related complications was 7.3%.

CONCLUSIONS

In moderate or severe PH pregnant patients with severe clinical symptoms, perioperative insertion of PAC helps to monitor the perinatal pulmonary arterial pressure(PAP) and guide treatment, potentially improving clinical outcomes and lowering the short term mortality. PAC can't be replaced by echocardiography in measuring PAP.

Efficacy of Goal-Directed Therapy Using Bioreactance Cardiac Output Monitoring after Valvular Heart Surgery

PURPOSE

We compared the efficacy of postoperative hemodynamic goal-directed therapy (GDT) using a pulmonary artery catheter (PAC) and bioreactance-based noninvasive cardiac output monitoring (NICOM) in patients with atrial fibrillation undergoing valvular heart surgery.

MATERIALS AND METHODS

Fifty eight patients were randomized into two groups of GDT with common goals to maintain a mean arterial pressure of 60-80 mm Hg and cardiac index ≥2 L/min/m²: the PAC group (n=29), based on pulmonary capillary wedge pressure, and the NICOM group (n=29), based on changes in stroke volume index after passive leg raising. The primary efficacy variable was length of hospital stay. Secondary efficacy variables included resource utilization including vasopressor and inotropic requirement, fluid balance, and major morbidity endpoints.

RESULTS

Patient characteristics and operative data were similar between the groups, except that significantly more patients underwent double valve replacement in the NICOM group. The lengths of hospital stay were not different between the two groups (12.2±4.8 days vs. 10.8±4.0 days, p=0.239). Numbers of patients requiring epinephrine (5 vs. 0, p=0.019) and ventilator care >24 h (6 vs. 1, p=0.044) were significantly higher in the PAC group. The PAC group also required significantly larger amounts of colloid (1652±519 mL vs. 11430±463 mL, p=0.004).

CONCLUSION

NICOM-based postoperative hemodynamic GDT showed promising results in patients with atrial fibrillation undergoing valvular heart surgery in terms of resource utilization.

Pulmonary vascular and right ventricular reserve in patients with normalized resting hemodynamics after pulmonary endarterectomy

Background

Patients with normalized mean pulmonary artery pressure (mPAP) after pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) do not always regain normal exercise capacity. We evaluated right ventricular function, its interaction with both pulsatile and resistive afterload, and the effect of sildenafil during exercise in these patients.

Methods and Results

Fourteen healthy controls, 15 CTEPH patients, and 7 patients with normalized resting mPAP (≤25 mm Hg) post‐PEA underwent cardiopulmonary exercise testing, followed by cardiac magnetic resonance imaging with simultaneous invasive mPAP measurement during incremental supine cycling exercise. Peak oxygen consumption and peak heart rate were significantly reduced in post‐PEA and CTEPH patients compared to controls. The mPAP–cardiac output slope was steeper in post‐PEA patients than in controls and similar to CTEPH. Relative to controls, resting right ventricular ejection fraction was reduced in CTEPH, but not in post‐PEA patients. In contrast, peak exercise right ventricular ejection fraction was reduced both in post‐PEA and CTEPH patients. Exercise led to reduction of pulmonary arterial compliance in all groups. Nevertheless, resting pulmonary arterial compliance values in CTEPH and post‐PEA patients were even lower than those in controls at peak exercise. In post‐PEA patients, sildenafil did not affect resting hemodynamics nor right ventricular function, but decreased the mPAP/cardiac output slope and increased peak exercise right ventricular ejection fraction.

Conclusions

Exercise intolerance in post‐PEA patients is explained by abnormal pulmonary vascular reserve and chronotropic incompetence. The mPAP/cardiac output slope and pulmonary arterial compliance are sensitive measures demonstrating abnormal resistive and pulsatile pulmonary vascular function in post‐PEA patients. These abnormalities are partially attenuated with sildenafil.

Pleth variability index and fluid responsiveness of hemodynamically stable patients after cardiothoracic surgery

BACKGROUND

Fluid responsiveness is a measure of preload dependence and is defined as an increase in cardiac output due to volume expansion. Recent publications have suggested that variation in amplitude of the pulse oximetry waveform may be predictive of fluid responsiveness. The pleth variability index (PVI) was developed as a noninvasive bedside measurement of this variation in the pulse oximetry waveform.

OBJECTIVES

To measure the discriminatory value of PVI for predicting fluid responsiveness as measured by pulmonary artery catheter thermodilution in patients after cardiothoracic surgery.

METHODS

A prospective observational study of hemodynamically stable postoperative cardiac surgery patients with pulmonary artery catheters. A fingertip sensor was used to measure PVI. Vital signs, PVI, and cardiac index were measured before, during, and after passive leg raise. Fluid responsiveness was defined by increase in cardiac index of greater than 15% during passive leg raise. The discriminatory value of PVI was assessed by using the Wilcoxon method to measure the area under the receiver operating curve.

RESULTS

In 13 months, 47 patients (24 receiving mechanical ventilation, 23 spontaneously breathing) were enrolled. Fluid responsiveness was noted in 42% of intubated patients and 48% of spontaneously breathing patients. PVI was not adequate to discriminate fluid responsiveness in intubated patients (area under curve, 0.63; P = .16) or spontaneously breathing patients (area under curve, 0.41; P = .75).

CONCLUSIONS

Among postoperative cardiac surgery patients, PVI is not reliable for predicting fluid responsiveness as measured by pulmonary artery catheter thermodilution, regardless of ventilatory status.

Correlation of cardiac output measured by non-invasive continuous cardiac output monitoring (NICOM) and thermodilution in patients undergoing off-pump coronary artery bypass surgery

Purpose

This observational study was designed to evaluate the clinical value of cardiac output (CO) obtained via bioreactance (NICOM™) as compared with values of CO obtained via thermodilution (using pulmonary artery catheter, Vigilance™) and the thoracic bioimpedance (BioZ.com™), in patients undergoing off-pump coronary artery bypass surgery.

Methods

Fifty American Society of Anesthesiologists physical status I–III patients, aged 38–81 years, scheduled for off-pump coronary artery bypass surgery were enrolled in this study. CO data (NCO, BCO, PCO) were recorded during the operative period at ten time points after stable hemodynamic conditions were achieved.

Results

The equation of the relationship between the PCO and NCO is PCO = 0.945 × NCO + 0.328 (r = 0.77), and that of PCO and BCO is PCO = 0.965 × BCO + 0.729 (r = 0.63). Furthermore, no statistical difference was found between PCO versus NCO (mean (SD): 4.4 (1.1) versus 4.4 (0.9), p = 0.431). A significant correlation was found between PCO and NCO (r = 0.77, p < 0.001). Correlation was also found between PCO and BCO (r = 0.63, p < 0.001).

Conclusions

The NICOM device is a safe, convenient, and reliable device for measuring continuous non-invasive cardiac output and cardiac index, and the trends of change in CO during the surgery are similar between NICOM and PAC.

Cardiac output monitoring with pulmonary versus transpulmonary thermodilution during liver transplantation: interchangeable methods?

BACKGROUND

Liver transplantation (LT) implies hemodynamic instability, making invasive monitoring of cardiac output (CO) mandatory. Intermittent thermodilution with pulmonary artery catheter (PAC) remains the clinical gold standard to measure CO. The agreement between PAC and new monitoring methods in LT needs to be further investigated. Our aim is to clarify whether cardiac index (CI) measurements with transpulmonary intermittent thermodilution, and continuous pulmonary thermodilution methods agree sufficiently with those performed intermittently with PAC to be considered interchangeable during LT.

METHODS

We studied prospectively hemodynamic parameters of 72 consecutive patients undergoing LT. Each CI was obtained simultaneously with three different techniques: intermittent (PACi) and continuous (CCI) pulmonary artery thermodilution with PAC, and intermittent transpulmonary thermodilution (TPTD) with PiCCO2 in 8 time points of the procedure, obtaining 1350 paired measurements. Exclusion criteria was retransplantation. The statistical Bland Altman method for repeated measures was used to assess agreement, and polar plot methodology to evaluate trending ability.

RESULTS

Analysis of agreement between PACi and TPTD measurements (N.=474 paired measurements) showed a bias of -0.42 L/min/m2, 95% limits of agreement (95%LoA) of ±1.5 L/min/m2 and percentage error of 45%. PACi-CCI comparisons (N.=431) showed bias of -0.02 L/min/m2, 95%LoA of ±1.96 L/min/m2, and percentage error of 64%. These results demonstrated questionable clinical agreement between PACi and TPTD, and no agreement between PACi and CCI. TPTD and CCI showed poor CO trending ability.

CONCLUSION

Continuous pulmonary thermodilution with PAC is not an alternative monitoring method of CO. Transpulmonary thermodilution CO monitoring with PiCCO2 shows too questionable agreement with the clinical gold standard (PACi) being in the limit of acceptance to be considered interchangeable during liver transplantation.

[A case of obstruction in the left internal jugular vein which both ultrasound prescan and chest computed tomography could not detect before the insertion of a pulmonary artery catheter]

In a 54-year-old man, at the time of anesthesia administration during the Bentall re-operation, a preoperative ultrasound scan showed right internal jugular vein thrombosis before insertion of a pulmonary artery catheter into the right internal jugular vein. Therefore, we performed the insertion after confirming that the left internal jugular vein was safe via a preoperative ultrasound and chest computed tomography (CT). Although we could insert the catheter sheath, contrast imaging revealed that the pulmonary artery catheter had advanced no further than approximately 15 cm into the left internal jugular vein. Similar advancement was noted when inserting the pulmonary artery catheter under fluroscopic guidance. This indicated an obstruction in the confluence of the left internal jugular vein and the brachiocephalic vein. A postoperative chest contrast CT showed thrombosis in the confluence of the left internal jugular vein and the brachiocephalic vein. Considering that the chest CT scan was performed 2 months before the surgery, it is necessary to perform imaging again before surgery.

Catheter-directed clot fragmentation using the Cleaner™ device in a patient presenting with massive pulmonary embolism

Massive pulmonary embolism not amenable to systemic thrombolysis is a therapeutic challenge. Catheter directed clot fragmentation and thrombolysis have been efficacious in this setting. We describe successfully treating a massive pulmonary embolism with catheter-directed thrombolysis and clot fragmentation using local tPA, aspiration, and the Cleaner™ device in a patient with an absolute contraindication to systemic thrombolysis.

Evaluation of patients with heart failure

Heart failure is one of the most prevalent cardiovascular diseases in the United States, and is associated with significant morbidity, mortality, and costs. Prompt diagnosis may help decrease mortality, hospital stay, and costs related to treatment. A complete heart failure evaluation comprises a comprehensive history and physical examination, echocardiogram, and diagnostic tools that provide information regarding the etiology of heart failure, related complications, and prognosis in order to prescribe appropriate therapy, monitor response to therapy, and transition expeditiously to advanced therapies when needed. Emerging technologies and biomarkers may provide better risk stratification and more accurate determination of cause and progression.