[Summary of the consensus document: "Clinical practice guide for the management of low cardiac output syndrome in the postoperative period of heart surgery"]. / Resumen del documento de consenso «Guías de práctica clínica para el manejo del síndrome de bajo gasto cardiaco en el postoperatorio de cirugía cardiaca¼

Low cardiac output syndrome is a potential complication in cardiac surgery patients and is associated with increased morbidity and mortality. This guide provides recommendations for the management of these patients, immediately after surgery and following admission to the ICU. The recommendations are grouped into different sections, addressing from the most basic concepts such as definition of the disorder to the different sections of basic and advanced monitoring, and culminating with the complex management of this syndrome. We propose an algorithm for initial management, as well as two others for ventricular failure (predominantly left or right). Most of the recommendations are based on expert consensus, due to the lack of randomized trials of adequate design and sample size in patients of this kind. The quality of evidence and strength of the recommendations were based on the GRADE methodology. The guide is presented as a list of recommendations (with the level of evidence for each recommendation) for each question on the selected topic. For each question, justification of the recommendations is then provided.

[Clinical practice guide for the management of low cardiac output syndrome in the postoperative period of heart surgery]. / Guías de práctica clínica para el manejo del síndrome de bajo gasto cardíaco en el postoperatorio de cirugía cardíaca.

The low cardiac output syndrome is a potential complication in cardiac surgery patients and associated with increased morbidity and mortality. This guide is to provide recommendations for the management of these patients, immediately after surgery, admitted to the ICU. The recommendations are grouped into different sections, trying to answer from the most basic concepts such as the definition to the different sections of basic and advanced monitoring and ending with the complex management of this syndrome. We propose an algorithm for initial management, as well as two other for ventricular failure (predominantly left or right). Most of the recommendations are based on expert consensus because of the lack of randomized trials of adequate design and sample size in this group of patients. The quality of evidence and strength of the recommendations were made following the GRADE methodology. The guide is presented as a list of recommendations (and level of evidence for each recommendation) for each question on the selected topic. Then for each question, we proceed to the justification of the recommendations.

Prognosis after heart transplant in patients with pulmonary hypertension secondary to cardiopathy.

INTRODUCTION: Pulmonary hypertension (PHT) is associated with greater posttransplant mortality. In the last few years, many vasodilator drugs have been developed and some patients have therefore been transplanted. However, conflicting data exist regarding the impact of reversible PHT on posttransplant outcomes. The aim of this study was to determine the evolution of our transplanted patients with reactive PHT and the causes of right cardiac insufficiency and perioperative mortality. MATERIAL AND METHODS: We performed a retrospective analysis of 39 consecutive heart transplant recipients from January 2005 to December 2006. We analyzed significant pretransplant PHT, the percentage of emergency transplants, surgical technique, as well as ischemia and extracorporeal circulation times. RESULTS: Before transplantation, significant PHT was present in 12 patients (30.8%), all of whom had a positive acute vasoreactivity test or response to oral treatment with pulmonary vasodilators. A nonsignificant tendency to increased posttransplant mortality was observed among patients with pretransplant PHT. We observed a significant increase in mortality in patients with prolonged operative times, over the third percentile, odds ratio (OR) for ECC of 21% (P = .001) and OR for prolonged ischemia time of 9.5% (P = .022). However, mortality did not increase significantly in cases of emergent transplantation (P = .08) or in the use of the Shumway bicaval surgical technique (P = .9). CONCLUSIONS: There seemed to be a slight tendency to increased mortality among patients with reversible HTP, suggesting that high-risk patients need closer monitoring but are not absolutely contraindicated for transplantation.

Application of the McCluskey Index to predict blood product requirements during liver transplantation.

BACKGROUND: A recent study proposed a risk index (McCluskey index) based on 7 parameters to identify the transfusion needs of patients during surgery and in the first 24 hours postoperation. The initial objective of our study was to validate this predictor for blood product transfusions. PATIENTS AND METHODS: We undertook a retrospective, observational study of all liver transplant patients between January 1, 2005 and December 31, 2006. The following variables were recorded for each patient: age, gender, patient comorbidity, biochemical values prior to liver transplantation, and transfusion needs. RESULTS: Comparing the transfusion needs of those patients with scores <5 with those of scores >/=5, we observed significant differences in terms of the use of red blood cell concentrates, plasma, and platelets, both during the first 24 hours and in the total number. The index sensitivity was 80% (95% confidence interval [CI]: 71.23-88.76), with a specificity of 84.21% (95% CI: 67.81-100), where the positive predictive value was 95.52% (95% CI: 90.57-100.4) and the negative predictive value was 50% (95% CI: 32.67-67.32). CONCLUSION: The McCluskey index showed sufficient sensitivity and specificity to predict which patients will require a massive transfusion.

Comparison between two drugs on the hemodynamic evaluation of pulmonary hypertension prior to heart transplantation.

INTRODUCTION: Invasive estimation of pulmonary pressure is part of the usual protocol prior to heart transplantation. The aim of this study was to compare the results of 2 different vasodilators, nitric oxide (NO) and prostacyclin, in an acute vasodilator test (AVT) for patients with pulmonary venous hypertension. MATERIALS AND METHODS: From January 2000 to December 2006, 94 right-sided heart catheterizations were performed in our center within pretransplantation evaluations. AVT was performed if the mean pulmonary artery pressure (mPAP) >35 mm Hg or if the pulmonary vascular resistance (PVR) was >4 Wood units (WU). Epoprostenol was administered to 40 patients, NO to 6 patients, and both agents to 8 patients. RESULTS: A significant decrease in both mPAP and PVR was shown with maximum doses of epoprostenol, with an average variation of 8.96 mm Hg in mPAP (P < .001) and 3.26 WU in PVR (P < .001). An increased cardiac output (CO) was observed with epoprostenol, with a mean difference of 1.9 L/min (P < .001) at maximum compared with baseline doses. A tendency for the mPAP and PVR to decrease was also observed with maximum NO doses, with mean decreases of mPAP and PVR of 5.62 mm Hg and 1.14 WU, respectively. A tendency for CO to decrease was observed with NO (0.75 L/min; P = .039). CONCLUSIONS: In our experience, NO is the best drug for AVT due to its pulmonary tree selectivity. A study with epoprostenol was complementary; both drugs can be used in these patients prior to heart transplantation.

Correlation of echocardiographic and hemodynamic parameters in pulmonary hypertension assessment prior to heart transplantation.

INTRODUCTION: Invasive assessment of pulmonary artery pressure (PAP), via right heart catheterization, is part of the usual protocol prior to heart transplantation. Echocardiography is considered a valuable technique to evaluate PAP. We sought to determine the reliability of measurements of PAP via a noninvasive technique, echocardiography, in relation to the estimated PAP via right catheterization. We also determined its safety when invasive procedures are restricted to just patients with pulmonary hypertension (PHT) according to echocardiographic parameters. MATERIALS AND METHODS: We performed a retrospective study of 67 right catheterizations performed in our hospital, within the heart transplant study protocol, from January 2000 to December 2006. PAP parameters were estimated by echocardiography and right catheterization. RESULTS: Hemodynamically, 57.1% of the patients had severe PHT (more than 45 mm Hg mean PAP); 13.2% moderate PHT (between 35 and 45 mm Hg mean PAP); 12.1% had mild PHT (between 25 and 35 mm Hg mean PAP); and 17.6% of patients showed no PHT. Pearson correlation index with systolic PAP (estimated via echocardiography) and mean PAP (calculated via invasive method) was 0.69 (P < .001). PHT was considered significant when systolic PAP estimated via echocardiography reached more than 40 mm Hg and mean PAP estimated via right catheterization reached more than 35 mm Hg, the value from which the vasodilator test was carried out. According to these parameters, echocardiography showed a sensitivity of 89% to diagnose significant PHT and 46% specificity, with positive and negative predictive values of 70% and 76%, respectively.

Short-term Use of Ventricular Assist Device in a Patient With Restrictive Cardiomyopathy: A Case Report.

The CentriMag (Levitronix LLC, Waltham, MA, USA) ventricular assist device is a centrifugal pump designed for short-term support in patients with cardiogenic shock. In patients with restrictive physiology, there is some concern about the use of these devices due a very small ventricular cavity. We review the evolution of a 32-year-old woman with restrictive cardiomyopathy, moderate pulmonary hypertension, and severe biventricular systo-diastolic dysfunction in whom a biventricular Centrimag device was implanted due to a progressive clinical worsening.

Pharmacokinetic evaluation of mycophenolic acid profiles during the period immediately following an orthotopic liver transplant.

BACKGROUND: Area under the curve (AUC) limited sampling strategies have been proposed to improve the efficiency of mycophenolic acid (MPA), treatment of the transplanted patient. Our objective was to develop a model in the initial phase of the transplantation that explains the variability in the pharmacokinetic behavior of MPA in the immediate posttransplant period, following treatment with mycophenolate mofetil (MMF) in adult liver transplantation. METHODS: One hundred ten pharmacokinetic simplified sampling profiles were collected, including four samples over a 6-hour postdose interval, in over 60 patients treated with cyclosporine or tacrolimus, MMF, and steroids, combining Daclizumab in more than a third of the patients. For an enzyme-multiplied immunoassay technique method was established for MPA estimates. The correlation between the AUC and the plasma concentration points was established using a multiple linear regression with various equations for three different pharmacokinetic groups. RESULTS: The maximum mean values of MPA AUC and predose concentration (C0h) (20.8 +/- 11.8 and 2.3 +/- 1.8, respectively) were reached on the third day. The single sample showing the greatest correlation with the MPA AUC was the one collected after 3 hours (r(2) = 0.575); 59.1% of profiles displayed a single peak with more than half showing a tmax >/= 3 hours. CONCLUSIONS: This profile analysis during the first few weeks highlighted the problems in determining therapeutic targets. Profiles showing a double peak revealed the marked influence of the enterohepatic cycle on MPA concentrations during the initial phase.

[Predictive factors of neurological complications in the period immediately after liver transplant: experiences in the Centro de Investigaciones Médico Quirúrgicas in Cuba]. / Factores predictivos de las complicaciones neurológicas en el postrasplante hepático inmediato: experiencia en el Centro de Investigaciones Médico Quirúrgicas de Cuba.

INTRODUCTION: Liver transplant (LT) is today a first choice procedure in a group of hepatic diseases in their acute and chronic terminal stages. It is not, however, a technique that is completely free of complications and those of a neurological nature constitute between 8 47% of those reported. AIMS. The purpose of this study is to present the immediate neurological complications (NC) found in our patients, as well as to determine the predictive factors and their relation to the mortality rate. PATIENTS AND METHODS: From the medical records of 26 patients who received LT at the CIMEQ (July 1999 December 2001), we collected a group of variables related to the donor, the surgical procedure and the post operative period and associated them to the occurrence of NC while these patients were in the ICU. RESULTS: NC were found in 16 patients (61.5%), the most frequent being encephalopathy (30.8%), tremor (26.9%), and convulsions (19.2%). No relation was found between the presence of NC and prior hepatic encephalopathy, the use of a suboptimal donor, nor did it represent a significant increase in the mortality rate. There was a significant relation with LT to recipients rated as grade C on the Child Pugh classification system, the presence of intraoperative hypotension (p= 0.0164) and primary dysfunction of the liver graft (p= 0.041). CONCLUSIONS: NC represented a significant cause of morbidity in the period following a liver transplant in our series, although they had no significant repercussion on the mortality rate. Their presence is related to variables concerning the recipient, the surgical procedure itself and the immediate post operative period.

Changes of lactate levels during cardiopulmonary bypass in patients undergoing cardiac transplantation: possible early marker of morbidity and mortality.

OBJECTIVES: High levels of lactate are associated with tissue hypoperfusion during cardiac surgery resulting in postoperative morbidity and mortality among patients undergoing cardiopulmonary bypass (CBP). Our goal was to evaluate the change in lactate levels during CBP for their possible predictive value for complications after heart transplant surgery. MATERIALS AND METHODS: From January to December 2010 we studied lactate levels in 16 heart transplant patients. Arterial blood samples were collected before, during, and after cardiopulmonary bypass on admission to the intensive care unit (ICU). Lactate levels were measured using the cobas B221 (Roche Diagnostic). The neurological, lung, and kidney complications were associated with mortality within 30 days. RESULTS: One patient displayed lactate levels > 2 mmol/L before bypass while 4 (25%) showed levels > 4 mmol/L during CPB. Lactate values higher than or equal to 4 mmol/L on ICU admission occurred in nine patients (56%). Postoperative mortality was higher among the group with levels above below 4 mmol/L on ICU admission (18.7% vs 6.2%). Neurological complications were observed in 22% of patients with elevated levels as opposed to none of the patients with levels below 4 mmol/L. Pulmonary complications were noted in 22% of patients with high lactate values versus 0% among the other group. CONCLUSION: Hyperlactemia above certain levels occurring during CPB serve as a biomarker to identify early postoperative morbidity and mortality.

Kidney failure after heart transplantation.

BACKGROUND AND PURPOSE: Heart transplantation is a procedure with a high mortality rate. Altered kidney function (AKF) after a heart transplant is common. The purpose of this study was to determine the incidence of and associated factors for renal dysfunction among patients who underwent heart transplantation in our hospital between January 2006 and November 2008. PATIENTS AND METHODS: This retrospective observational study was performed on all patients receiving a heart transplant between January 1, 2006 and November 15, 2008. The following variables were recorded: patient comorbidities, indication, presurgical urea and creatinine levels, donor variables, surgical procedure, and postoperative features. RESULTS: A total of 54 heart transplantations were performed with 68.5% of patients being male. The average age at transplant was 49.52 years (±13.45 y) and the mean weight 72.5 kg (±14.8 kg). Overall mortality was 28.30%. Of the 54 patients, 70.4% showed AKF during the first week after transplantation; 30.61% were in stage III according to the Acute Kidney Injury classification. There were no statistically significant differences between the group of patients with versus without renal failure, except for the extracorporeal surgery time, which was significantly longer among those patients who had AKF, and glycemia, which was also higher in the immediate postoperative period. Analysis of patient mortality showed no significant differences for the patients with AKF (80% vs 68.4%; P=31). CONCLUSIONS: The rate of acute kidney failure was high (70.4%), as was the use of chronic renal replacement therapy (28.85%), but it decreased considerably when followed over time.

Considerations regarding major bleeding after cardiac transplantation.

Postoperative bleeding is one of the most frequent complications after cardiac surgery, leading to longer stays in the intensive care unit (ICU) and the hospital as well as increased morbidity and mortality. We designed an observational prospective study to evaluate early complications after cardiac transplantation, focusing on major bleeding and transfusion requirements. We also evaluated whether massive transfusion was related to increased morbidity and mortality. In patients who received ≥6 blood units, we observed significant differences regarding the need for continuous renal replacement techniques (50% vs 12.5%; P=.01) and ICU mortality (33.3% vs 4%; P=.01). This difference in mortality was also observed when comparing plasma transfusion requirements (35.3% vs 9.4%; P=.04). The overall mortality rate was 24.50%, showing significant differences in patients with massive transfusion (83.3% vs 37.8%; P=.008). In conclusion, perioperative bleeding and massive transfusion were associated with increased morbidity and mortality in this group of patients, which may prompt a review of surgical procedures and the introduction of new techniques, such as thromboelastography.

Severe rhabdomyolysis after allogeneic transplantation of facial structures: a case report.

We present a patient with panfacial neurofibromatosis type 1 who underwent allogeneic transplantation of facial structures, which was complicated by severe rhabdomyolysis and temporary oligoanuria. Because of his underlying disease, this 35 year-old man, weighing 68 kg and with a body mass index (BMI) of 27, had undergone 17 operations for resection modeling of hypertrophied tissues, either alone or combined with static suspension techniques. He finally underwent allogeneic transplantation of facial structures. In the early hours of the postoperative period, in the context of a systemic inflammatory response syndrome, he experienced severe rhabdomyolysis, with elevation of the muscle enzyme creatine kinase producing a minor impact on kidney function. The patient was discharged home at 12 weeks after the transplantation.