Clinical Outcomes of Low-Risk Patients Undergoing Beating-Heart Surgery With or Without Pulmonary Artery Catheterization

Perioperative Care in Cardiac Surgery: A Joint Consensus Statement by the Enhanced Recovery After Surgery (ERAS) Cardiac Society, ERAS International Society, and The Society of Thoracic Surgeons (STS)

Enhanced Recovery After Surgery (ERAS) programs have been shown to lessen surgical insult, promote recovery, and improve postoperative clinical outcomes across a number of specialty operations. A core tenet of ERAS involves the provision of protocolized evidence-based perioperative interventions. Given both the growing enthusiasm for applying ERAS principles to cardiac surgery and the broad scope of relevant interventions, an international, multidisciplinary expert panel was assembled to derive a list of potential program elements, review the literature, and provide a statement regarding clinical practice for each topic area. This article summarizes those consensus statements and their accompanying evidence. These results provide the foundation for best practice for the management of the adult patient undergoing cardiac surgery.

Pulmonary artery catheter receipt among cardiac surgery patients from the national inpatient sample (1999-2019): Prevalence, predictors and hospitalization charges

Despite limited evidence to support its efficacy, use of pulmonary artery catheter (PAC), a relatively expensive medical device, for monitoring clinical status and guiding therapeutic interventions, has become standard of care in many settings, and especially during and after cardiac surgery. We examined the prevalence and predictors of PAC use and its association with hospitalization charges among cardiac surgery patients generally and for each selected subgroup of high-risk or complex surgical procedures. We conducted an analysis on 1,442,528 records from the National Inpatient Sample (1999-2019) that included cardiac surgery patients ≥18 years of age. Subgroups were categorized based on the presence of specific disorders like tricuspid or mitral valve disease, pulmonary hypertension, heart failure, or cardiac surgery combinations. Multivariable regression models were constructed to assess predictors of PAC use as well as PAC use as a predictor of loge hospitalization charges controlling for patient and hospital characteristics. Based on International Classification of Diseases procedure codes, PAC use was prevalent among 7.15 % of cardiac surgery hospitalizations, and hospitalization charges were estimated at $191,345, with no differences according to PAC use. Overall, being female, having Charlson comorbidity index (CCI) > 0, and non-payer (versus Medicare) status were independently associated with PAC use. Among the subgroup with the selected conditions, being female, having CCI>0, and being a Medicaid (versus Medicare) recipient were independently associated with PAC use, whereas elective admission was inversely related to PAC use. Among the subgroup without the selected conditions, having a CCI >0, elective admission, and non-payer (vs. Medicare) status were independently associated with PAC use. PAC use was not independently related to hospitalization charges overall or among subgroups. In conclusion, approximately 7 % of cardiac surgery hospitalizations received a PAC, with no differences in charges according to PAC use and disparities in PAC use driven by sex, elective admission, CCI and health insurance status. Large randomized trials are required to characterize the safety, efficacy, and cost-effectiveness of PAC use among distinct groups of patients undergoing cardiac surgery.

No association between pulmonary artery catheter use and postoperative complications in off-pump coronary artery bypass grafting: a single-center pilot study

BACKGROUND

A pulmonary artery catheter is often used in cardiac surgery despite its uncertain effectiveness. The aim of this pilot study was to investigate the associations between the use of a pulmonary artery catheter and clinical outcomes in off-pump coronary artery bypass grafting.

METHODS

Patients over 20 years of age who had undergone off-pump coronary artery bypass grafting between December 2018 and November 2021 were enrolled in this single-center retrospective pilot study. The propensity score of pulmonary artery catheterization was calculated. Multivariate analysis including the propensity score as a covariate was performed to assess clinical outcomes. The primary outcome was the composite outcome of in-hospital death, unplanned intraoperative conversion to cardiopulmonary bypass, resuscitated cardiac arrest, mechanical circulatory support, myocardial infarction, stroke, new initiation of renal replacement therapy, inhaled nitric oxide, re-intubation and tracheostomy.

RESULTS

Among the 315 patients who were enrolled, 298 were included in the final analysis. A pulmonary artery catheter was inserted in 131 patients. There were 50 patients with the composite outcome including two in-hospital deaths. Multivariate logistic regression analysis showed that pulmonary artery catheterization was not significantly related to the composite outcome. Clinical outcomes worsened significantly as the number of anastomoses increased (odds ratio: 1.450, 95% confidence interval: 1.040-2.040, P=0.029).

CONCLUSIONS

Pulmonary artery catheterization did not improve the clinical outcomes in off-pump coronary artery bypass grafting in this pilot study.

Association of pulmonary artery catheter with in-hospital outcomes after cardiac surgery in the United States: National Inpatient Sample 1999-2019

To examine associations of pulmonary artery catheter (PAC) use with in-hospital death and hospital length of stay (days) overall and within subgroups of hospitalized cardiac surgery patients. Secondary analyses of 1999-2019 National Inpatient Sample data were performed using 969,034 records (68% male, mean age: 65 years) representing adult cardiac surgery patients in the United States. A subgroup of 323,929 records corresponded to patients with congestive heart failure, pulmonary hypertension, mitral/tricuspid valve disease and/or combined surgeries. We evaluated PAC in relation to clinical outcomes using regression and targeted maximum likelihood estimation (TMLE). Hospitalized cardiac surgery patients experienced more in-hospital deaths and longer stays if they had ≥ 1 subgroup characteristics. For risk-adjusted models, in-hospital deaths were similar among recipients and non-recipients of PAC (odds ratio [OR] 1.04, 95% confidence interval [CI] 0.96, 1.12), although PAC was associated with more in-hospital deaths among the subgroup with congestive heart failure (OR 1.14, 95% CI 1.03, 1.26). PAC recipients experienced shorter stays than non-recipients (β =  - 0.40, 95% CI - 0.64, - 0.15), with variations by subgroup. We obtained comparable results using TMLE. In this retrospective cohort study, PAC was associated with shorter stays and similar in-hospital death rates among cardiac surgery patients. Worse clinical outcomes associated with PAC were observed only among patients with congestive heart failure. Prospective cohort studies and randomized controlled trials are needed to confirm and extend these preliminary findings.

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.

The Pulmonary Artery Catheter in the Perioperative Setting: Should It Still Be Used?

The pulmonary artery catheter (PAC) was introduced into clinical practice in the 1970s and was initially used to monitor patients with acute myocardial infarctions. The indications for using the PAC quickly expanded to critically ill patients in the intensive care unit as well as in the perioperative setting in patients undergoing major cardiac and noncardiac surgery. The utilization of the PAC is surrounded by multiple controversies, with literature claiming its benefits in the perioperative setting, and other publications showing no benefit. The right interpretation of the hemodynamic parameters measured by the PAC and its clinical implications are of the utmost essence in order to guide a specific therapy. Even though clinical trials have not shown a reduction in mortality with the use of the PAC, it still remains a valuable tool in a wide variety of clinical settings. In general, the right selection of the patient population (high-risk patients with or without hemodynamic instability undergoing high-risk procedures) as well as the right clinical setting (centers with experience and expertise) are essential in order for the patient to benefit most from PAC use.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered. Structure: Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered.

STRUCTURE

Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

The Routine Use of the Pulmonary Artery Catheter Should Be Abandoned

The pulmonary artery catheter (PAC) is the most common method of measuring cardiac output in cardiac surgery. However, its use has always been questioned in terms of survival benefit, specifically with regard to the accuracy of its measurements and its invasive nature, with the potential for serious complications. In this review we aimed to develop a clear understanding of the pitfalls of the use of PAC, and discuss its risks and available alternatives. We conclude that there is no indication for the routine use of PAC such that clinicians should carefully consider the clinical risks and benefits on a patient by patient basis.

The Pulmonary Artery Catheter in Anesthesia Practice in 2007: An Historical Overview With Emphasis on the Past 6 Years

The pulmonary artery catheter has been widely used in anesthesiology and critical care medicine. Until recently, only retrospective or relatively weak prospective studies examining its effect on outcome had been performed. Over the past 6 years, however, a number of well-designed prospective trials and statistically sound retrospective studies have been completed. All of these show no benefit and some even reveal a potential for increased morbidity. Reasons for this device's inability to improve outcome are numerous, including wrong patient selection and misinterpretation, but the most impressive and convincing evidence is that filling pressures measured from the catheter, particularly the pulmonary artery “wedge” pressure, have no physiologic value. The wedge pressure has been shown to not correlate with other accepted methods of determining left ventricular filling or volume or intravascular volume and also does not help to generate cardiac function curves. Therefore, knowledge of it may actually lead to incorrect management more frequently than not.

Perioperative fluid therapy: a statement from the international Fluid Optimization Group

BACKGROUND

Perioperative fluid therapy remains a highly debated topic. Its purpose is to maintain or restore effective circulating blood volume during the immediate perioperative period. Maintaining effective circulating blood volume and pressure are key components of assuring adequate organ perfusion while avoiding the risks associated with either organ hypo- or hyperperfusion. Relative to perioperative fluid therapy, three inescapable conclusions exist: overhydration is bad, underhydration is bad, and what we assume about the fluid status of our patients may be incorrect. There is wide variability of practice, both between individuals and institutions. The aims of this paper are to clearly define the risks and benefits of fluid choices within the perioperative space, to describe current evidence-based methodologies for their administration, and ultimately to reduce the variability with which perioperative fluids are administered.

METHODS

Based on the abovementioned acknowledgements, a group of 72 researchers, well known within the field of fluid resuscitation, were invited, via email, to attend a meeting that was held in Chicago in 2011 to discuss perioperative fluid therapy. From the 72 invitees, 14 researchers representing 7 countries attended, and thus, the international Fluid Optimization Group (FOG) came into existence. These researches, working collaboratively, have reviewed the data from 162 different fluid resuscitation papers including both operative and intensive care unit populations. This manuscript is the result of 3 years of evidence-based, discussions, analysis, and synthesis of the currently known risks and benefits of individual fluids and the best methods for administering them.

RESULTS

The results of this review paper provide an overview of the components of an effective perioperative fluid administration plan and address both the physiologic principles and outcomes of fluid administration.

CONCLUSIONS

We recommend that both perioperative fluid choice and therapy be individualized. Patients should receive fluid therapy guided by predefined physiologic targets. Specifically, fluids should be administered when patients require augmentation of their perfusion and are also volume responsive. This paper provides a general approach to fluid therapy and practical recommendations.

Use of pulmonary artery catheter in coronary artery bypass graft. Costs and long-term outcomes

Background

Pulmonary artery catheters (PAC) are used widely to monitor hemodynamics in patients undergoing coronary bypass graft (CABG) surgery. However, recent studies have raised concerns regarding both the effectiveness and safety of PAC. Therefore, our aim was to determine the effects of the use of PAC on the short- and long-term health and economic outcomes of patients undergoing CABG.

Methods

1361 Chinese patients who consecutively underwent isolated, primary CABG at the Cardiovascular Institute of Fuwai Hospital from June 1, 2012 to December 31, 2012 were included in this study. Of all the patients, 453 received PAC during operation (PAC group) and 908 received no PAC therapy (control group). Short-term and long-term mortality and major complications were analyzed with multivariate regression analysis and propensity score matched-pair analysis was used to yield two well-matched groups for further comparison.

Results

The patients who were managed with PAC more often received intraoperative vasoactive drugs dopamine (70.9% vs. 45.5%; P<0.001) and epinephrine (7.7% vs. 2.6%; P<0.001). In addition, costs for initial hospitalization were higher for PAC patients ($14,535 vs. $13,873, respectively, p = 0.004). PAC use was neither associated with the perioperative mortality or major complications, nor was it associated with long-term mortality and major adverse cardiac and cerebrovascular events. In addition, comparison between two well-matched groups showed no significant differences either in baseline characteristics or in short-term and long-term outcomes.

Conclusions

There is no clear indication of any benefit or harm in managing CABG patients with PAC. However, use of PAC in CABG is more expensive. That is, PAC use increased costs without benefit and thus appears unjustified for routine use in CABG surgery.

A systematic review of goal directed fluid therapy: rating of evidence for goals and monitoring methods

PURPOSE

To review the literature on goal directed fluid therapy and evaluate the quality of evidence for each combination of goal and monitoring method.

MATERIALS AND METHODS

A search of major digital databases and hand search of references was conducted. All studies assessing the clinical utility of a specific fluid therapy goal or set of goals using any monitoring method were included. Data was extracted using a pre-determined pro forma and papers were evaluated using GRADE principles to assess evidence quality.

RESULTS

Eighty-one papers met the inclusion criteria, investigating 31 goals and 22 methods for monitoring fluid therapy in 13052 patients. In total there were 118 different goal/method combinations. Goals with high evidence quality were central venous lactate and stroke volume index. Goals with moderate quality evidence were sublingual microcirculation flow, the oxygen extraction ratio, cardiac index, cardiac output, and SVC collapsibility index.

CONCLUSIONS

This review has highlighted the plethora of goals and methods for monitoring fluid therapy. Strikingly, there is scant high quality evidence, in particular for non-invasive G/M combinations in non-operative and non-intensive care settings. There is an urgent need to address this research gap, which will be helped by methodologies to compare utility of G/M combinations.

Cardiac output assessed by invasive and minimally invasive techniques

Cardiac output (CO) measurement has long been considered essential to the assessment and guidance of therapeutic decisions in critically ill patients and for patients undergoing certain high-risk surgeries. Despite controversies, complications and inherent errors in measurement, pulmonary artery catheter (PAC) continuous and intermittent bolus techniques of CO measurement continue to be the gold standard. Newer techniques provide less invasive alternatives; however, currently available monitors are unable to provide central circulation pressures or true mixed venous saturations. Esophageal Doppler and pulse contour monitors can predict fluid responsiveness and have been shown to decrease postoperative morbidity. Many minimally invasive techniques continue to suffer from decreased accuracy and reliability under periods of hemodynamic instability, and so few have reached the level of interchangeability with the PAC.

Does the Pulmonary Artery Catheter Still Have a Role in the Perioperative Period?

The pulmonary artery catheter (PAC) was introduced into clinical practice in the early 1970s. Its use quickly expanded beyond patients with acute myocardial infarction to critically ill patients in the intensive care unit. Increasingly, it was used in the perioperative period in patients having major cardiac and noncardiac surgery. Publication of large observational studies suggested that patients with a PAC were more likely to suffer major morbidity or mortality, but this was difficult to assess because patients who had a PAC inserted were often sicker, with more severe pathology, and were therefore more likely to die. The PAC is a monitoring device and information alone is unlikely to influence outcome unless it is linked to a proven therapy. Several thousand articles on the use of the PAC now exist, but in general, the quality of this literature is poor. Much of the data are not randomised, have small sample sizes and include patients with greatly differing pathological states. It is unclear which, if any, of the PAC-guided therapies are actually beneficial for patients. Despite these flaws, there is no clear evidence of benefit, nor harm, in cardiac, intensive care or perioperative patients. Selected indications for the PAC may remain, such as complex cardiac surgery or solid organ transplantation. However, its routine use is difficult to justify and increasingly, most of the haemodynamic data available from the PAC can be obtained less invasively with echocardiography.

Perioperative haemodynamic therapy

PURPOSE OF REVIEW

To discuss the perioperative monitoring tools and targets for haemodynamic optimization and to assess the influence of goal-directed therapy (GDT) on organ function, complications and outcome in different categories of surgical patients.

RECENT FINDINGS

The choice of perioperative haemodynamic monitoring for GDT depends on the surgery-related and the patient-related risk. Conventional monitoring and minimally invasive approaches can be used for perioperative optimization of low-risk to moderate-risk patients. Thermodilution methods and continuous cardiac output/oxygen transport monitoring are the most reliable techniques for major surgery and high-risk/unstable patients. An important goal of perioperative haemodynamic therapy is to maintain cardiac function and organ perfusion, optimizing the balance between oxygen delivery and consumption. Several studies, using different monitoring tools and end-points, have shown that GDT provides optimal haemodynamic performance, improves organ function, reduces the number of complications and time to ICU and hospital discharge and decreases the mortality rate in high-risk surgical patients.

SUMMARY

GDT provides a number of benefits in major surgery. Based on adequate monitoring, the goal-directed algorithms facilitate early detection of pathophysiological changes and influence the perioperative haemodynamic therapy that can improve the clinical outcome. The perioperative GDT should be early, adequate and individualized for every patient.

S3 guidelines for intensive care in cardiac surgery patients: hemodynamic monitoring and cardiocirculary system

Hemodynamic monitoring and adequate volume-therapy, as well as the treatment with positive inotropic drugs and vasopressors are the basic principles of the postoperative intensive care treatment of patient after cardiothoracic surgery. The goal of these S3 guidelines is to evaluate the recommendations in regard to evidence based medicine and to define therapy goals for monitoring and therapy. In context with the clinical situation the evaluation of the different hemodynamic parameters allows the development of a therapeutic concept and the definition of goal criteria to evaluate the effect of treatment. Up to now there are only guidelines for subareas of postoperative treatment of cardiothoracic surgical patients, like the use of a pulmonary artery catheter or the transesophageal echocardiography. The German Society for Thoracic and Cardiovascular Surgery (Deutsche Gesellschaft für Thorax-, Herz- und Gefässchirurgie, DGTHG) and the German Society for Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft für Anästhesiologie und lntensivmedizin, DGAI) made an approach to ensure and improve the quality of the postoperative intensive care medicine after cardiothoracic surgery by the development of S3 consensus-based treatment guidelines. Goal of this guideline is to assess the available monitoring methods with regard to indication, procedures, predication, limits, contraindications and risks for use. The differentiated therapy of volume-replacement, positive inotropic support and vasoactive drugs, the therapy with vasodilatators, inodilatators and calcium sensitizers and the use of intra-aortic balloon pumps will also be addressed. The guideline has been developed following the recommendations for the development of guidelines by the Association of the Scientific Medical Societies in Germany (AWMF). The presented key messages of the guidelines were approved after two consensus meetings under the moderation of the Association of the Scientific Medical Societies in Germany (AWMF).

Single transpulmonary thermodilution and continuous monitoring of central venous oxygen saturation during off-pump coronary surgery

BACKGROUND

Off-pump coronary artery bypass grafting (OPCAB) requires thorough monitoring of hemodynamics and oxygen transport. Our aim was to find out whether therapeutic guidance during and after OPCAB, using an algorithm based on advanced monitoring, influences perioperative hemodynamic and fluid management as well as the length of post-operative ICU and hospital stay.

METHODS

Patients were randomized into two groups of hemodynamic monitoring: the conventional monitoring (CM) group (n=20) and the advanced monitoring (AM) group (n=20). In the CM group, therapy was guided by central venous pressure, mean arterial pressure (MAP) and heart rate (HR), and in the AM group by the intrathoracic blood volume index, MAP, HR, central venous oxygen saturation (ScvO(2)) and cardiac index (CI). The measurements were performed before and during surgery, and at 2, 4 and 6 h post-operatively.

RESULTS

In the AM group, colloids and dobutamine were given more frequently and were accompanied by increments in ScvO(2), CI and oxygen delivery compared with baseline. The percentage of ephedrine administration was higher in the CM group. The algorithm guided by AM decreased time until achieving the status of 'fit for ICU discharge' and post-operative hospital stay by 15% and 25%, respectively.

CONCLUSIONS

A goal-directed algorithm based on advanced hemodynamic monitoring and continuous measurement of ScvO(2) facilitates early detection and correction of hemodynamic changes and influences the strategy for fluid therapy that can improve the course of post-operative period after coronary artery bypass grafting on the beating heart.

Relationship between echocardiographic index of ventricular filling pressure and intraoperative haemodynamic changes during off-pump coronary bypass surgery

BACKGROUND

The ratio of mitral velocity to early-diastolic velocity of the mitral annulus (E/e') is an indicator of diastolic function representing acute loading conditions of the left ventricle. We tested the efficacy of E/e' as a predictor of haemodynamic derangement during off-pump coronary artery bypass surgery (OPCAB), when heart displacement causes loading changes.

METHODS AND RESULTS

Fifty patients with left ventricular (LV) ejection fraction >or= 50% were divided into two groups; E/e'<8 (normal LV filling pressure, n=25) and >15 (increased LV filling pressure, n=25). Haemodynamic measurements were recorded after induction of anaesthesia, during grafting, and after sternum closure. Patients' characteristics and operative data were similar between the groups. Cardiac index and mixed venous oxygen saturation were significantly lower during grafting and after sternum closure in the E/e'>15 group, compared with E/e'<8 group and with the baseline values. The E/e'>15 group required significantly longer ventilation time and length of stay in the intensive care unit.

CONCLUSIONS

Even in patients with preserved systolic LV function, patients with E/e'>15 were more prone to undergo a significant decrease in cardiac output during OPCAB, which did not return to baseline level after completion of grafting. Whether this finding is associated with increased morbidity and mortality should be validated.

[Minimally invasive cardiopulmonary monitoring with the PiCCO Plus system]

Insertion of a central venous catheter and an arterial catheter would be indicated in hemodynamically unstable or severely hypoxic patients in critical care units. In this setting, cardiorespiratory monitoring by transpulmonary thermodilution (TPTD) can be considered minimally invasive given that only a single arterial thermodilution catheter and a single central venous catheter are required to be connected to a specific monitor (the PiCCO Plus, Pulsion Medical Systems, Munich, Germany). TDTP simultaneously measures cardiac output, preloading, and cardiac function in hemodynamically unstable patients and predicts the response to volume. The technique can be managed by any health care professional. In hypoxic patients, TDTP identifies cases of pulmonary edema that might benefit from a negative fluid balance, evaluates pulmonary vascular permeability, facilitates our understanding of pathophysiologic mechanisms of hypoxemia, and predicts the likelihood of deleterious hemodynamic effects of positive end-expiratory pressures.

Iatrogenic pulmonary artery rupture

PURPOSE OF REVIEW

Pulmonary artery rupture is probably the most devastating complication associated with the use of the pulmonary artery catheter. This rare but disastrous situation requires a clear intervention plan.

RECENT FINDINGS

The initial presentation of pulmonary artery ruptures may be as obvious as a massive pulmonary hemorrhage or as subtle as a cough associated with minimal hemoptysis, or it may even be totally asymptomatic. A patient presenting any clinical manifestation of pulmonary artery rupture may develop a pulmonary artery false aneurysm, which is the accumulation of blood in an aneurismal sac compressed by lung parenchyma. This condition requires intervention because delayed hemorrhage may occur and recurrence can be massive and fatal. Following an initial episode of suspected pulmonary artery rupture, the patient should undergo immediate radiological investigation. If a diagnosis of pulmonary artery false aneurysm is confirmed, selective angiographic embolization helps reduce morbidity and mortality.

SUMMARY

The incidence of pulmonary artery ruptures is probably underestimated because many hemoptysis episodes or radiological infiltrations associated with pulmonary artery catheter use are not investigated. Also, the natural evolution of the pulmonary artery false aneurysm is unknown. The incidence of spontaneous healing, bleeding recurrence or asymptomatic persistence is unknown following formation of a pulmonary artery false aneurysm.