The role of trans-oesophageal echocardiography for perioperative cardiovascular monitoring during orthotopic liver transplantation

Utility of transesophageal echocardiography during orthotopic liver transplantation: A narrative review

Orthotopic liver transplantation (OLT) is the standard of care for patients suffering from end stage liver disease (ESLD). This is a high-risk procedure with the potential for hemorrhage, large shifts in preload and afterload, and release of vasoactive mediators that can have profound effects on hemodynamic equilibrium. In addition, patients with ESLD can have preexisting coronary artery disease, cirrhotic cardiomyopathy, porto-pulomary hypertension and imbalanced coagulation. As cardiovascular involvement is invariable and patient are at an appreciable risk of intraoperative cardiac arrest, Trans esophageal echocardiography (TEE) is increasingly becoming a routinely utilized monitor during OLT in patients without contraindications to its use. A comprehensive TEE assessment performed by trained operators provides a wealth of information on baseline cardiac function, while a focused study specific for the ESLD patients can help in prompt diagnosis and treatment of critical events. Future studies utilizing TEE will eventually optimize examination safety, quality, permit patient risk stratification, provide intraoperative guidance, and allow for evaluation of graft vasculature.

Incidence of Gastrointestinal Bleeding After Transesophageal Echocardiography Use in Orthotopic Liver Transplantation

The risk of upper gastrointestinal bleeding (UGIB) after transesophageal echocardiography (TEE) in patients with high grade esophageal varices (EV) that are undergoing Orthotopic Liver transplantation (OLT) is poorly understood. This was a retrospective single-centre cohort study in all patients that underwent OLT at Queen Elizabeth Hospital Birmingham between September 2016 and September 2018. The primary outcome was to determine the incidence of UGIB in patients that have undergone OLT with EV that received TEE. 401 patients were included in the study, of which 320 (80%) received TEE. The incidence of post-operative UGIB in patients that received TEE was 1.6% (5/320) in the entire cohort: 2.7% (4/149) in patients with no evidence of EV and 0.6% (1/171) in patients with EV. UGIB occurred in 1 patient with grade 2 EV and did not occur in patients with grade 1 or 3 EV. The incidence of UGIB in patients that received TEE was not statistically different to patients that did not: 1.6% (5/320) vs. 3.7% (3/81) p = 0.218. In conclusion, in patients that underwent OLT, intra-operative TEE use was associated with low rates of UGIB, even in cohorts with high grade EV. This suggests that TEE is a relatively safe method of haemodynamic monitoring in patients undergoing OLT.

What's New in Cirrhotic Cardiomyopathy?-Review Article

Cirrhotic cardiomyopathy (CCM) is a relatively new medical term. The constant development of novel diagnostic and clinical tools continuously delivers new data and findings about this broad disorder. The purpose of this review is to summarize current facts about CCM, identify gaps of knowledge, and indicate the direction in which to prepare an updated definition of CCM. We performed a review of the literature using scientific data sources with an emphasis on the latest findings. CCM is a clinical manifestation of disorders in the circulatory system in the course of portal hypertension. It is characterized by impaired left ventricular systolic and diastolic dysfunction, and electrophysiological abnormalities, especially QT interval prolongation. However, signs and symptoms reported by patients are non-specific and include reduced exercise tolerance, fatigue, peripheral oedema, and ascites. The disease usually remains asymptomatic with almost normal heart function, unless patients are exposed to stress or exertion. Unfortunately, due to the subclinical course, CCM is rarely recognized. Orthotopic liver transplantation (OLTx) seems to improve circulatory function although there is no consensus about its positive effect, with reported cases of heart failure onset after transplantation. Researchers indicate a careful pre-, peri-, and post-transplant cardiac assessment as a crucial point in detecting CCM and improving patients’ prognosis. There is also an urgent need to update the CCM definition and establish a diagnostic algorithm for early diagnosis of CCM as well as a specific treatment of this condition.

Hemodynamic Instability During Liver Transplantation in Patients With End-stage Liver Disease: A Consensus Document from ILTS, LICAGE, and SATA

Hemodynamic instability (HDI) during liver transplantation (LT) can be difficult to manage and increases postoperative morbidity and mortality. In addition to surgical causes of HDI, patient- and graft-related factors are also important. Nitric oxide-mediated vasodilatation is a common denominator associated with end-stage liver disease related to HDI. Despite intense investigation, optimal management strategies remain elusive. In this consensus article, experts from the International Liver Transplantation Society, the Liver Intensive Care Group of Europe, and the Society for the Advancement of Transplant Anesthesia performed a rigorous review of the most current literature regarding the epidemiology, causes, and management of HDI during LT. Special attention has been paid to unique LT-associated conditions including the causes and management of vasoplegic syndrome, cardiomyopathies, LT-related arrhythmias, right and left ventricular dysfunction, and the specifics of medical and fluid management in end-stage liver disease as well as problems specifically related to portal circulation. When possible, management recommendations are made.

Safety and Benefit of Transesophageal Echocardiography in Liver Transplant Surgery: A Position Paper From the Society for the Advancement of Transplant Anesthesia (SATA)

More anesthesiologists are routinely using transesophageal echocardiography (TEE) during liver transplant surgery, but the effects on patient outcome are unknown. Transplant anesthesiologists are therefore uncertain if they should undergo additional training and adopt TEE. In response to these clinical questions, the Society for the Advancement of Transplant Anesthesia appointed experts in liver transplantation and who are certified in TEE to evaluate all available published evidence on the topic. The aim was to produce a summary with greater explanatory power than individual reports to guide transplant anesthesiologists in their decision to use TEE. An exhaustive search recovered 51 articles of uncontrolled clinical observations. Topics chosen for this study were effectiveness and safety because they were a major or minor topic in all articles. The pattern of clinical use was a common topic and was included to provide contextual information. Summarized observations showed effectiveness as the ability to make a new and unexpected diagnosis and to direct the choice of clinical management. These were reported in each stage of liver transplant surgery. There were observations that TEE facilitated rapid diagnosis of life-threatening conditions difficult to identify with other types of monitoring commonly used in the operating room. Real-time diagnosis by TEE images made anesthesiologists confident in their choice of interventions, especially those with a high risk of complications such as use of anticoagulants for intracardiac thrombosis. The summarized observations in this systematic review suggest that TEE is an effective form of monitoring with a safety profile similar to that in cardiac surgery patients.

Use, Training, and Opinions About Effectiveness of Transesophageal Echocardiography in Adult Liver Transplantation Among Anesthesiologists in the United States

Study Objective. Describe transesophageal echocardiography (TEE) use, preparatory training and opinions about clinical importance, and future training pathways in a sample of liver transplant anesthesiologists. Design. Online survey questionnaire. Setting. Liver Transplant Centers in the United States. Participants. Director of Liver Transplant Anesthesia or designated alternate respondent. Results. A total of 79 Directors or alternates from 111 (71%) centers were identified. There were 56 responses (71%) representing 433 transplant anesthesiologists who cared for 63.3% of liver transplant cases performed in 2015. Basic TEE certification was reported more frequently (64%) than advanced (53.6%). At least one team member used TEE in over 90% of responding centers. Most respondents (83.9%) agreed TEE provided unique and valuable clinical information but were equally divided about future training pathways (on the job learning vs basic TEE certification). Conclusion. TEE use in liver transplantation is growing with a substantial increase in basic TEE certified users. Transplant anesthesiologists support basic certification but an equal number believe there should be more applied training at the site of care.

Transesophageal echocardiography in orthotopic liver transplantation: a comprehensive intraoperative monitoring tool

Intraoperative transesophageal echocardiography is a minimally invasive monitoring tool that can provide real-time visual information on ventricular function and hemodynamic volume status in patients undergoing liver transplantation. The American Association for the Study of Liver Diseases states that transesophageal echocardiography should be used in all liver transplant candidates in order to assess chamber sizes, hypertrophy, systolic and diastolic function, valvular function, and left ventricle outflow tract obstruction. However, intraoperative transesophageal echocardiography can be used to "visualize" other organs too; thanks to its proximity and access to multiple acoustic windows: liver, lung, spleen, and kidney. Although only limited scientific evidence exists promoting this comprehensive use, we describe the feasibility of TEE in the setting of liver transplantation: it is a highly valuable tool, not only as a cardiovascular monitoring, but also as a tool to evaluate lungs and pleural spaces, to assess hepatic vein blood flow and inferior vena cava anastomosis and patency, i.e., in cases of modified surgical techniques. The aim of this case series is to add our own experience of TEE as a comprehensive intraoperative monitoring tool in the field of orthotopic liver transplantation (and major liver resection) to the literature.

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.

Anesthetic Management of Pediatric Liver and Kidney Transplantation

Pediatric patients with liver dysfunction and renal failure may exhibit many comorbidities. There are often associated congenital syndromes to be taken into account. Liver and renal transplantation offer a solution and substantial improvement in quality of life. Anesthetic management of pediatric liver and renal transplantation has not been well described. There are key differences between adults and children undergoing these procedures, and acknowledgment of some key principles provide a solid foundation to optimize perioperative outcomes. This article provides an overview of the perioperative management and considerations in pediatric patients undergoing liver and renal transplantation.

Cirrhotic cardiomyopathy: Implications for liver transplantation

The majority of patients on a waiting list for liver transplantation have end-stage liver disease. Because of the marked peripheral vasodilatation of end-stage cirrhosis that masks a latent myocardial dysfunction, cardiac abnormalities in the resting state are usually subclinical and escape the attention of physicians. However, when challenged, the systolic and diastolic contractile responses are attenuated. In addition to these contractile abnormalities, morphological changes, such as enlargement or hypertrophy of cardiac chambers, and electrophysiological repolarization changes, including a prolonged QT interval, can be observed. The constellation of these cardiac abnormalities is termed cirrhotic cardiomyopathy. Liver transplantation induces significant cardiovascular stress. Clamping of the inferior vena cava and portal vein, hemorrhage and blood/volume infusion, and ischemia/reperfusion all cause hemodynamic fluctuation. The changing cardiac preload and afterload status increases the cardiac workload, and thus, the previously subclinical ventricular dysfunction may manifest as overt heart failure during the operative and perioperative periods. Cardiac dysfunction contributes to morbidity and mortality associated with liver transplantation. Cardiovascular events are the third leading cause of death in liver recipients. However, because liver transplantation is the only definitive treatment for end-stage liver failure and also appears to reverse cardiac abnormalities, it is important to understand the challenges of the heart in liver transplantation. This review focuses on cardiac status before, during, and after liver transplantation. Liver Transplantation 23 826-835 2017 AASLD.

The photoplethysmographic amplitude to pulse pressure ratio can track sudden changes in vascular compliance and resistance during liver graft reperfusion: A beat-to-beat analysis

During liver transplantation, the thermodilution cardiac output (CO) technique cannot respond to sudden hemodynamic changes associated with postreperfusion syndrome. Photoplethysmography (PPG) can reflect changes in intravascular volume and thus can be used to assess vasomotor tone and arterial stiffness on the pressure-volume relation. We investigated whether a beat-to-beat analysis of the arterial pressure-PPG relationship can estimate dynamic changes in vascular characteristics immediately after liver graft reperfusion.In 10 recipients, arterial blood pressure and PPG waveforms recorded simultaneously were analyzed from the beginning of fall to nadir in systolic blood pressure immediately after reperfusion. On a beat-to-beat basis, we compared the ratio of the amplitude of PPG to arterial pulse pressure (PPGamp/PP, as relative vascular compliance) to total peripheral resistance (TPR) and Windkessel compliance (Cwk) obtained from the Modelflow CO algorithm.Following graft reperfusion, PPGamp/PP and Cwk increased (median 41.5%; P = .005 and 42.0%; P < .001, respectively), whereas TPR decreased (median -46.4%; P < .001). Beat-to-beat PPGamp/PP was negatively correlated with TPR (median r = -0.80 [95% CI -0.85 to -0.76] on linear regression and r = 0.84 [95% CI 0.73-0.92] on curvilinear regression), and was positively correlated with Cwk (median r = 0.86 [95% CI 0.81-0.91] on linear regression and r = 0.88 [95% CI 0.75-0.96] on curvilinear regression).Our results suggest that relative compliance, obtained from beat-to-beat analysis of PPG and arterial pressure waveforms, can track abrupt changes in vascular characteristics associated with postreperfusion syndrome. This simple index would contribute to differential diagnoses of sudden hypotension.

Intraoperative Management of High-Risk Liver Transplant Recipients: Concerns and Challenges

Liver transplantation (LT) offers patients with liver disease a real chance for long-term survival. In the past decade, successful survival after LT along with the Model for End-Stage Liver Disease-based allocation policy have increased willingness to accept patients with a higher risk profile and marginal organs and to prioritize the sickest patients on the waiting list. Therefore, the anesthesiologist now deals with very challenging patients. In the present review, we aimed to highlight key aspects of intraoperative LT management in high-risk patients and to place these aspects in the perspective of their impact on perioperative outcomes. Conservative standardized perioperative strategies mandate a switch toward accurate and tailored perioperative anesthetic care to maintain the steady improvement in recipient survival rates after LT. In our opinion, continuous assessment of fluid status and cardiac performance, strategies promoting graft decongestion, rational hemostatic management, and the identification of LT recipients with potential risk of vascular complications should constitute the cornerstone of intraoperative management.

Intraoperative Diagnosis of Intracardiac Thrombus During Orthotopic Liver Transplantation With Transesophageal Echocardiography: A Case Series and Literature Review

Anesthesia for orthotopic liver transplantation (OLT) is challenging for any anesthesiologist as the patients undergoing this procedure are among the most critically ill. Adding to the underlying complexity of OLT management is the rare complication of an intracardiac thrombus (ICT). Intracardiac thrombi can present following liver allograft reperfusion resulting in high morbidity and mortality. Currently there is no consensus treatment for ICT, and the gold standard for diagnosis is intraoperative transesophageal echocardiography (TEE); these 2 factors lead to a dangerous amalgam of the difficulty in diagnosing and treating the disease. We describe 2 separate cases in detail of ICT formation during OLT that were recognized and diagnosed with intraoperative TEE. These 2 cases highlight the important role of TEE in the management of ICT. A thorough literature review that follows analyzes our current understanding of ICT during OLT and the vital function of TEE by every anesthesiologists regardless of formal TEE training. Broader use of TEE during all OLTs can help narrow the anesthesiologist’s differential diagnosis during the acute phases of transplantation and should be considered in all liver transplant surgeries.

Anaesthesia and intensive care for simultaneous liver-kidney transplantation: A single-centre experience with 12 recipients

Background and Aims:

The perioperative management of patients presenting for simultaneous liver and kidney transplantation (SLKT) is a complex process. We analysed SLKTs performed in our institution to identify preoperative, intraoperative and post-operative challenges encountered in the management.

Methods:

We retrospectively studied the case records of 12 patients who underwent SLKT between 2009 and 2014 and analysed details of pre-operative evaluation and optimisation, intraoperative anaesthetic management and the implications of use of perioperative continuous renal replacement therapy (CRRT) and the post-operative course of these patients.

Results:

Of the total 12 cases, 4 were under 16 years of age. The indications for SLKT were primary hyperoxaluria (5), congenital hepatic fibrosis with polycystic kidney disease (2), ethanol-related end-stage liver disease (ESLD) with hepatorenal syndrome type 1 (1). Four patients had ESLD with end-stage renal disease due to other causes. Six recipients received live donor grafts and 6 patients received cadaveric grafts. Seven patients received intraoperative CRRT. Mean duration of surgery was 12.5 h. Cardiac output monitors used were trans-oesophageal echocardiogram (2), pulmonary artery catheter (1) and pulse contour cardiac output monitor (3). There was 1 sepsis-related mortality on 7^th post-operative day.

Conclusion:

A thorough pre-operative evaluation and optimisation, knowledge and anticipation of potential problems, and meticulous intraoperative fluid management guided by appropriate monitoring and use of CRRT when needed can help in achieving successful outcomes.

[Perioperative transesophageal echocardiography in non-cardiac surgery. Update]

AIM

The aim of this article is to impart knowledge concerning focused transesophageal echocardiographic examination (TEE) for non-cardiac surgery which is an essential part of perioperative monitoring. It allows a rapid echocardiographic examination without interference with the surgical field or under limited transthoracic examination conditions. New recommendations for a comprehensive perioperative TEE examination with expanded standard views and the recently published consensus statement for a shortened baseline examination were crucial for this study.

MATERIAL AND METHODS

The background is the peer-reviewed literature from PubMed.

RESULTS

Apart from cardiac surgery TEE has two main applications: firstly, the evaluation of patients developing acute life-threatening hemodynamic instability in the operating room, in the emergency room or in the intensive care unit (ICU). Secondly, TEE is used as planned intraoperative monitoring when severe hemodynamic, pulmonary or neurological complications are expected because of the type of surgery or due to the cardiopulmonary medical history of the patient. In 2013 a total of 11 relevant standard views were defined for the basic perioperative TEE examination in non-cardiac surgery. These 11 views should be performed for each patient. Appropriate extension to a comprehensive examination may be necessary if complex pathology is obvious.

DISCUSSION

Even in non-cardiac surgery TEE is an important tool allowing clarification of a life-threatening perioperative hemodynamic instability within a few minutes. Furthermore, the hemodynamic management of high-risk patients can be facilitated. Appropriate qualification and continuous training are necessary in order to assure the competence of the examiner.

Postreperfusion syndrome during liver transplantation

As surgical and graft preservation techniques have improved and immunosuppressive drugs have advanced, liver transplantation (LT) is now considered the gold standard for treating patients with end-stage liver disease worldwide. However, despite the improved survival following LT, severe hemodynamic disturbances during LT remain a serious issue for the anesthesiologist. The greatest hemodynamic disturbance is postreperfusion syndrome (PRS), which occurs at reperfusion of the donated liver after unclamping of the portal vein. PRS is characterized by marked decreases in mean arterial pressure and systemic vascular resistance, and moderate increases in pulmonary arterial pressure and central venous pressure. The underlying pathophysiological mechanisms of PRS are complex. Moreover, risk factors associated with PRS are not fully understood. Rapid and appropriate treatment with vasopressors, volume replacement, or venesection must be provided depending on the cause of the hemodynamic disturbance when hemodynamic instability becomes profound after reperfusion. The negative effects of PRS on postoperative early morbidity and mortality are clear, but the effect of PRS on postoperative long-term mortality remains a matter of debate.

Transoesophageal echocardiography during liver transplantation

Liver transplantation (LT) has become the standard of care for patients with end stage liver disease. The allocation of organs, which prioritizes the sickest patients, has made the management of liver transplant candidates more complex both as regards their comorbidities and their higher risk of perioperative complications. Patients undergoing LT frequently display considerable physiological changes during the procedures as a result of both the disease process and the surgery. Transoesophageal echocardiography (TEE), which visualizes dynamic cardiac function and overall contractility, has become essential for perioperative LT management and can optimize the anaesthetic management of these highly complex patients. Moreover, TEE can provide useful information on volume status and the adequacy of therapeutic interventions and can diagnose early intraoperative complications, such as the embolization of large vessels or development of pulmonary hypertension. In this review, directed at clinicians who manage TEE during LT, we show why the procedure merits a place in challenging anaesthetic environment and how it can provide essential information in the perioperative management of compromised patients undergoing this very complex surgical procedure.

Complications related to intraoperative transesophageal echocardiography in liver transplantation

Purpose

Intraoperative transesophageal echocardiography (TEE) has commonly been used for evaluating cardiac function and monitoring hemodynamic parameters during complex surgical cases. Anesthesiologists may be dissuaded from using TEE in orthotopic liver transplantation (OLT) out of concern about rupture of esophageal varices. Complications associated with TEE in OLT were evaluated.

Methods

We retrospectively reviewed charts and TEE videos of all OLT cases from January 2003 through December 2013 at Mayo Clinic (Jacksonville, Florida).

Results

Of the 1811 OLTs performed, we identified 232 patients who underwent intraoperative TEE. Esophageal variceal status was documented during presurgical esophagogastroduodenoscopy in 230 of the 232 patients. Of these, 69 (30.0 %), had no varices; 113 (49.1 %), 41 (17.8 %), and 7 (3.0 %) had grades I, II, and III varices, respectively. Two patients (0.9 %) had no EGD performed because of acute liver failure. During OLT, 1 variceal rupture (0.4 %) occurred after placement of an oral gastric tube and TEE probe; the patient required intraoperative variceal banding. Most patients had preexisting coagulopathy at the time of probe placement. The mean (SD) laboratory test results were as follows: prothrombin time, 21.7 (6.6) seconds; international normalized ratio, 1.9 (1.3); partial thromboplastin time, 43.8 (13.3) seconds; platelet, 93.7 (60.8) × 1000/μL; and fibrinogen, 237.8 (127.6) mg/dL.

Conclusion

TEE was a relatively safe procedure with a low incidence of major hemorrhagic complications in patients with documented esophagogastric varices and coagulopathy undergoing OLT. It appeared to effectively disclose cardiac information and allowed rapid reaction for proper patient management.

Peri-operative assessment of right heart function: role of echocardiography

The right heart contributes significantly to overall cardiac function. Right ventricular (RV) haemodynamics and function have been defined to be physiologically different from the left ventricle, and yet independently associated with outcomes in a spectrum of conditions. In particular, RV function has been shown to influence prognosis of patients undergoing surgery. The assessment of right heart function during the intra-operative and immediate postoperative periods plays an important role in the clinical management of patients having surgery. While a number of techniques are available for the assessment of the right heart intra-operatively, echocardiography remains the prime choice being least invasive, relatively safe, readily accessible and cost-effective. Advancements in the field of echocardiographic have improved ability to assess right heart function. This review examines the role echocardiography and advances in this imaging modality in the assessment of right heart function within the peri-operative setting.

Cirrhotic cardiomyopathy: Implications for the perioperative management of liver transplant patients

Cirrhotic cardiomyopathy is a disease that has only recently been recognised as a definitive clinical entity. In the setting of liver cirrhosis, it is characterized by a blunted inotropic and chronotropic response to stress, impaired diastolic relaxation of the myocardium and prolongation of the QT interval in the absence of other known cardiac disease. A key pathological feature is the persistent over-activation of the sympathetic nervous system in cirrhosis, which leads to down-regulation and dysfunction of the β-adrenergic receptor. Diagnosis can be made using a combination of echocardiography (resting and stress), tissue Doppler imaging, cardiac magnetic resonance imaging, 12-lead electrocardiogram and measurement of biomarkers. There are significant implications of cirrhotic cardiomyopathy in a number of clinical situations in which there is an increased physiological demand, which can lead to acute cardiac decompensation and heart failure. Prior to transplantation there is an increased risk of hepatorenal syndrome, cardiac failure following transjugular intrahepatic portosystemic shunt insertion and increased risk of arrhythmias during acute gastrointestinal bleeding. Liver transplantation presents the greatest physiological challenge with a further risk of acute cardiac decompensation. Peri-operative management should involve appropriate choice of graft and minimization of large fluctuations in preload and afterload. The avoidance of cardiac failure during this period has important prognostic implications, as there is evidence to suggest a long-term resolution of the abnormalities in cirrhotic cardiomyopathy.

United States practice patterns in the use of transesophageal echocardiography during adult liver transplantation

OBJECTIVE

To characterize contemporary practice patterns in the use of transesophageal echocardiography during adult liver transplantation and to identify factors preventing more frequent use.

DESIGN

Online questionnaire.

SETTING

Liver transplantation centers in the United States performing 12 or more adult liver transplants in 2011.

PARTICIPANTS

One representative from each qualifying center: The transplant anesthesiology director, a transplant anesthesiologist personally known to the authors, or the department of anesthesiology chair.

INTERVENTIONS

Three e-mail attempts were made to solicit participation in the study between June and August 2012.

MEASUREMENTS AND MAIN RESULTS

Of the 97 institutions identified, an anesthesiologist from each of 79 (81.4%) centers completed the questionnaire; 38.0% of centers reported routine use and 57.0% for special circumstances or rescue situations, yielding an overall use rate of 94.9%. This distribution was consistent regardless of operative volume, practice size, or academic affiliation. The sole factor predictive of routine transesophageal echocardiography use was an overlap between an institution's cardiac and transplant anesthesiology teams. In practices not routinely employing the technology, the most compelling reason was a sense that it was not necessary. Although 69.9% of transplant anesthesiologists reportedly were proficient in echocardiography, inadequate anesthesiologist training was also a strongly cited hindrance.

CONCLUSIONS

Transesophageal echocardiography during adult liver transplantation in the United States has become widely prevalent, with notable growth in its use as a routine diagnostic and monitoring modality. Almost all institutions now use the technology at least occasionally, with the participation of cardiac anesthesiologists being predictive of a center's routine use.

Complications related to invasive hemodynamic monitors during adult liver transplantation

The rate of complications directly related to invasive monitors during liver transplantation (LT) was reviewed in 1206 consecutive adult LTs performed over 8.6 yr (1/1/2004-7/31/2012). The designated anesthesiologists placed intra-operative monitors, including two arterial catheters (via the radial and the right femoral arteries), central venous catheters (a 9 Fr. catheter and an 18 Fr. veno-venous bypass [VVB] return cannula in an internal jugular vein), a pulmonary artery catheter, and a transesophageal echocardiography (TEE) probe. A 17 Fr. VVB drainage cannula was placed via the left femoral vein. No Clavien-Dindo Grade V (death) or Grade IV (organ dysfunction) complication was identified. Nine Grade III complications (requiring surgical intervention) and 15 Grade II complications (conservative treatment) were noted. Seven (0.58% in 1206 cases) were related to a femoral arterial line with Grade III of four; seven (0.58%) were due to VVB return cannula in the femoral vein with Grade III of one; four (0.33%) were related to central venous catheters with Grade III of two; four (0.33%) were due to a TEE probe with Grade III of two; and two minor complications (0.17%) that were related to a radial arterial line. No complication was observed with a pulmonary arterial catheter. Current invasive monitors placed during LT have an acceptable risk.

Liver transplantation: Advances and perioperative care

Liver transplantation is one of the treatments for many-life threatening liver diseases. Numerous advances in liver transplant surgery, anaesthesia and perioperative care have allowed for an increasing number of these procedures. The purpose of this review is to consider some of the important advances in perioperative care of liver transplant patients such as pre-operative evaluation, intraoperative monitoring and management and early extubation. A PubMed and EMBASE search of terms “Anaesthesia” and “Liver Transplantation” were performed with filters of articles in “English”, “Adult” and relevant recent publications of randomised control trial, editorial, systemic review and non-systemic review were selected and synthesized according to the author's personal and professional perspective in the field of liver transplantation and anaesthesia. The article outlines strategies in organ preservation, training and transplant database for further research.

Transesophageal echocardiography during orthotopic liver transplantation in patients with esophagoastric varices

BACKGROUND

Hemodynamic monitoring using transesophageal echocardiography (TEE) in patients with signs of portal hypertension undergoing orthotopic liver transplantation (OLT) carries potential risk of esophageal and gastric variceal hemorrhage. The aim of our retrospective analysis was to evaluate the safety of intraoperative TEE monitoring during OLT in patients with esophagogastric varices.

METHODS

A retrospective analysis of 396 liver transplant recipients was performed at the Medical University of Vienna monitored by TEE during OLT between 2003 and 2010.

RESULTS

Varices were documented by esophagogastroduodenoscopy in 287 (72.5%) of 396 analyzed patients: 130 (32.8%) varices grade I (<5 mm under insufflation) and 157 (39.6%) varices grade II (>5 mm under insufflation). Red spot signs were identified in 40 patients (10.1%). Most varices (82.2%) were documented in the esophagus, 4.2% in the stomach, and 13.6% in both (esophagus and stomach). Only one major bleeding occurred, and it was only in a case of one patient with an esophageal varix, which was treated with a balloon tamponade during OLT. Although patients with varices demonstrated a significantly longer prothrombin time and lower platelet count, there was no significant difference in the requirement for blood products among patients with and without varices.

CONCLUSIONS

TEE is a relatively safe method for monitoring cardiac performance with a low incidence of major hemorrhagic complications in patients with documented esophagogastric varices undergoing OLT.

Anaesthesia for Living Related Liver Transplantation

With the greater success of liver transplantation, livers from deceased donors are insufficient to meet the need for livers required for transplantation. In various parts of Asia, living related liver transplantation is the treatment for patients with end-stage liver disease. An overview of anaesthesia for both the donor and the recipient is described. Controversies involving epidural anaesthesia, blood loss prevention and blood conservation techniques in the donor are discussed. Various aspects in the anaesthetic management of the recipient are also looked at.

Perioperative monitoring in liver transplant patients

Liver transplant (LT) is a major surgical undertaking involving major fluid shifts, hemodynamic instability and metabolic derangements in a patient with preexisting liver failure and multisystemic derangements. Monitoring and organ support initiated in the preoperative phase is continued intraoperatively and into the postoperative phase to ensure an optimal outcome. As cardiovascular events are the leading cause of non-graft related death among LT recipients, major emphasis is placed on cardiovascular monitoring. The other essential monitoring are the continuous assessment of coagulapathy, extent of metabolic derangements, dyselectrolytemis and intracranial pressure monitoring in patients with fulminant hepatic failure. The type and extent of monitoring differs with need according to preexisting child status of the patient and the extent of systemic derangements. It also varies among transplant centers and is mainly determined by individual or institutional practices.

Transoesophageal echocardiography for monitoring liver surgery: data from a pilot study

A pilot study aimed to introduce intraoperative monitoring of liver surgery using transoesophageal echocardiography (TEE) is described. A set of TEE measurements was established as a protocol, consisting of left atrial (LA) dimension at the aortic valve plane; mitral velocity flow integral, calculation of stroke volume and cardiac output (CO); mitral annular plane systolic excursion; finally, right atrial area. A total of 165 measurements (on 21 patients) were performed, 31 occurring during hypotension. The conclusions reached were during acute blood loss LA dimension changed earlier than CVP, and, in one patient, a dynamic left ventricular (LV) obstruction was observed; in 3 patients a transient LV systolic dysfunction was documented. The comparison between 39 CO paired measurements obtained by TEE and PiCCO2 revealed a statistically significant correlation (P < 0.001, r = 0.83). In this pilot study TEE successfully answered the questions raised by the anesthesiologists. Larger cohort studies are needed to address this issue.

Optimizing cost-effectiveness in perioperative care for liver transplantation: a model for low- to medium-income countries

Although liver transplantation (LT) is a highly effective treatment, it has been considered too costly for publicly funded health systems in many countries with low to medium average incomes. However, with economic growth and improving results, some governments are reconsidering this position. Cost-effectiveness data for LT are limited, especially in perioperative care, and the techniques and costs vary widely between centers without overt differences in outcomes. Anesthesiologists working in new programs find it difficult to determine which modalities are essential, which are needed only in exceptional circumstances, and which may be omitted without effects on outcomes. We investigated key elements of preoperative evaluations, intraoperative management, and early postoperative care that might significantly affect costs in order to develop a best-value approach for new programs in resource-limited health systems. We identified all modalities of care commonly used in anesthesia and perioperative care for adult LT along with their costs. Those considered to be universally accepted as minimum requirements for safe care were excluded from the analysis, and so were those considered to be safe and low-cost, even when evidence of efficacy was lacking. The remaining items were, therefore, those with uncertain or context-restricted value and significant costs. A systematic review of the published evidence, practice surveys, and institutional guidelines was performed, and the evidence was graded and summarized. With respect to costs and benefits, each modality was then cited as strongly recommended, recommended or optional, or no recommendation was made because of insufficient evidence. Sixteen modalities, which included preoperative cardiovascular imaging, venovenous bypass, pulmonary artery catheterization, high-flow fluid warming devices, drug therapies for hemostasis, albumin, cell salvage, anesthetic drugs, personnel (staffing) requirements, and early extubation, were assessed. Only high-flow fluid warming was strongly recommended. The recommended modalities included preoperative echocardiography, cell salvage, tranexamic acid and early extubation. Six others were rated optional, and there was insufficient evidence for 5 modalities. We conclude that some costly techniques and treatments can be omitted without adverse effects on outcomes.

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.

Intraoperative management of liver transplant patients

Liver transplantation for end-stage liver disease results in excellent outcomes. Patient and graft outcome is closely monitored on a national level, and 1-year survival is between 80% and 95%. Liver transplantation relies on a multidisciplinary approach, with close involvement of anesthesiologists and intensivists. However, intraoperative care of these patients remains inconsistent and is highly institution dependent. This brief-review article will focus on controversial topics of intraoperative care. Existing evidence on intraoperative monitoring, intraoperative fluid and transfusion management, electrolyte and glucose management, postoperative patient disposition, and, lastly, anesthesia team management will be reviewed.

Perioperative considerations in patients with cirrhotic cardiomyopathy

PURPOSE OF REVIEW

This review aims to identify specific criteria for cirrhotic cardiomyopathy, examine the correlation with perioperative adverse outcomes and explore options for hemodynamic monitoring.

RECENT FINDINGS

Cirrhotic cardiomyopathy is characterized by an increase in cardiac output, blunted systolic contractile response to stress, diastolic dysfunction and electrophysiological abnormalities. Adverse events due to cirrhotic cardiomyopathy are not as well characterized, but evidence suggests that some cardiovascular complications during surgery and in the postoperative period are caused by an impaired response to physiological stress. New developments in hemodynamic monitoring using not only thermodilution technology provide more reliable information about cardiac performance than pressure-derived measures. Transesophogeal echocardiography also offers the physician new information including the ability to visualize heart structures, shape, and function.

SUMMARY

To detect cirrhotic cardiomyopathy, physicians must conduct a systematic examination of the patient. Overt manifestations of cirrhotic cardiomyopathy often only become evident after a patient is exposed to physiological or drug-induced stress. Appropriate hemodynamic monitoring is a cornerstone in the perioperative management of cirrhotic patients.

Effects of phlebotomy and phenylephrine infusion on portal venous pressure and systemic hemodynamics during liver transplantation

BACKGROUND

A regimen of fluid restriction, phlebotomy, vasopressors, and strict, protocol-guided product replacement has been associated with low blood product use during orthotopic liver transplantation. However, the physiologic basis of this strategy remains unclear. We hypothesized that a reduction of intravascular volume by phlebotomy would cause a decrease in portal venous pressure (PVP), which would be sustained during subsequent phenylephrine infusion, possibly explaining reduced bleeding. Because phenylephrine may increase central venous pressure (CVP), we questioned the validity of CVP as a correlate of cardiac filling in this context and compared it with other pulmonary artery catheter and transesophageal echocardiography-derived parameters. In particular, because optimal views for echocardiographic estimation of preload and stroke volume are not always applicable during liver transplantation, we evaluated the use of transmitral flow (TMF) early peak (E) velocity as a surrogate.

METHODS

In study 1, the changes in directly measured PVP and CVP were recorded before and after phlebotomy and phenylephrine infusion in 10 patients near the end of the dissection phase of liver transplantation. In study 2, transesophageal echocardiography-derived TMF velocity in early diastole was measured in 20 patients, and the changes were compared with changes in CVP, pulmonary artery pressure (PAP), pulmonary capillary wedge pressure (PCWP), cardiac output (CO), and calculated systemic vascular resistance (SVR) at the following times: postinduction, postphlebotomy, preclamping of the inferior vena cava, during clamping, and postunclamping.

RESULTS

Phlebotomy decreased PVP along with CO, PAP, PCWP, CVP, and TMF E velocity. Phenylephrine given after phlebotomy increased CVP, SVR, and arterial blood pressure but had no significant effect on CO, PAP, PCWP, or PVP. The change in TMF E velocity correlated well with the change in CO (Pearson correlation coefficient 95% confidence interval 0.738-0.917, P< or =0.015) but less well with the change in PAP (0.554-0.762, P< or =0.012) and PCWP (0.576-0.692, P< or =0.008). TMF E velocity did not correlate significantly with CVP or calculated SVR.

CONCLUSION

Phlebotomy during the dissection phase of liver transplantation decreased PVP, which was unaffected when phenylephrine infusion was used to restore systemic arterial pressure. This may contribute to a decrease in operative blood loss. CVP often increased in response to phenylephrine infusion and did not seem to reflect cardiac filling. The changes in TMF E velocity correlated well with the changes in CO, PAP, and PCWP during liver transplantation but not with the changes in CVP.

Hemodynamic monitoring in pigs undergoing orthotopic abdominal multivisceral transplantation

Anesthesia for abdominal multivisceral transplantation (MVTx) is challenging. Surgical success depends on hemodynamic stability throughout organ removal from the donor and engraftment in recipients. The aim of the current study was to summarize our experience with anesthetic management including monitoring of hemodynamic changes in pigs during MVTx procedures.

MATERIALS AND METHODS

Ten male pigs were randomly divided into two groups: donors and recipients for five MVTxs. A pulmonary artery catheter (PAC), transesophageal echocardiography (TEE), and pulse indicator continuous cardiac output (PiCCO) were used intraoperatively in recipients to monitor hemodynamic changes.

RESULTS

Two recipients had cardiac arrest and died intraoperatively presumably due to hypovolemia. The data obtained by PAC and TEE from three successful cases showed huge changes in hemodynamics during the stages of organ removal and reperfusion after engraftment. Use of PiCOO in one of those three cases allowed successful fluid management, resulting in stable intraoperative hemodynamics.

CONCLUSION

The anesthetic management for MVTx surgery was improved by PAC, TEE, and PiCOO monitoring.

Intraoperative hemodynamic monitoring during organ transplantation: what is new?

PURPOSE OF REVIEW

To highlight the recent developments in hemodynamic monitoring during liver and lung transplantation.

RECENT FINDINGS

Even though a consensus on intraoperative hemodynamic monitoring is still lacking, the most frequently monitoring tool used is the pulmonary artery catheter (PAC). The filling pressures are widely accepted as not being able to accurately define cardiac preload. On the contrary, the use of transesophageal echocardiography (TEE), although it is operator dependent and requires a prolonged training, is increasing during the intraoperative period to directly evaluate the cardiovascular function. New frontiers have been opened by the transpulmonary thermodilution: intrathoracic blood volume has been shown to have a better correlation with preload than the filling pressures. The advanced modified PAC permits evaluation of the right heart function and preload. Recently, right ventricular end diastolic volume has been shown to correlate better with preload than the filling pressures and also the left ventricular end diastolic area.

SUMMARY

The PAC still represents the most used intraoperative hemodynamic monitoring technique. TEE is increasing in popularity. Recent studies demonstrate that volumetric monitoring conducted with transpulmonary thermodilution and advanced volumetric PAC give good definition of preload and should be implemented in clinical practice.

Techniques of cardiac output measurement during liver transplantation: arterial pulse wave versus thermodilution

In this study, we compared continuous cardiac output (CO) obtained from the femoral arterial pressure by simulation of an aortic input impedance model [model-simulated cardiac output (MCO)] to thermodilution cardiac output (TDCO) determined by bolus injection during liver transplantation. Both variables were measured in 39 adult patients (13 females) every 10th minute during liver transplant surgery. Paired measurements were compared during the 4 phases of surgery-dissection, anhepatic phase, early reperfusion (the first 15 minutes after reperfusion), and late reperfusion (15-60 minutes after reperfusion)-without the detection of any significant difference between the 2 estimates of CO. TDCO ranged from 2.3 to 17.2 L/minute, and the bias (the mean difference between MCO and TDCO) prior to calibration was -0.4 +/- 1.6 L/minute (mean +/- standard deviation; 1309 paired measurements; 95% limits of agreement: -3.4 to 2.6 L/minute). After calibration of the first determined MCO by the simultaneously determined TDCO, the bias was 0.1 +/- 1.5 L/minute, with 57% (n = 744) of the comparisons being less than 1 L/minute and 35% (n = 453) being less than 0.5 L/minute; this was independent of the level of CO, and the mutual correlation coefficient was 0.812 (P < 0.001). This study indicates that during liver transplantation surgery, MCO reflects TDCO throughout the operation. Thus, for CO, this less invasive method appears to provide a reliable uninterrupted measurement during orthotopic liver transplantation.