Influence of coronary artery disease on outcomes after liver transplantation

Patients with coronary artery disease (CAD) who undergo liver transplantation (OLT) have been previously identified as a high-risk group. Since that identification, the management of CAD has undergone significant changes as has the cardiovascular screening and selection of patients for OLT. We retrospectively identified 42 patients with known CAD who underwent OLT to compare outcomes with a control group of 42 patients without CAD who were matched for gender, age, and primary liver disease. Mortality rates were higher in the CAD than the control group at 1 year (5 vs 1) and 3 years (11 vs 3; P < .05) although lower than previously reported (at 3 years, 26% vs 50%). New cardiovascular morbidity was also more frequent among the CAD than control group at 1 year (11 vs 3; P < .05) and 3 years (16 vs 4; P < .05). Although outcomes for patients with CAD undergoing OLT are improved from historical levels, they are still worse than those in patients without CAD despite current management and selection strategies.

Preoperative dobutamine stress echocardiography, intraoperative events, and intraoperative myocardial injury in liver transplantation

INTRODUCTION

The appropriate method of screening for coronary artery disease in patients who present for liver transplantation is currently uncertain.

METHODS

We assessed the utility of a screening protocol using dobutamine stress echocardiography (DSE) in 119 patients who underwent liver transplantation. Patients with cardiac risk factors had DSE performed, and those with positive results were referred for coronary angiography. Outcome was myocardial injury during liver transplantation determined by an elevation of cardiac troponin T measured after transplantation.

RESULTS

Seventy-three patients had DSE performed; eight were reported as positive for inducible ischemia. Seven of these patients underwent coronary angiography, and one had significant coronary artery disease. Postoperative troponin elevation occurred in 14 patients. There was no significant difference in the prevalence of troponin elevation in those patients with positive DSE versus those with negative DSE. No significant difference was identified in the prevalence of troponin elevation when comparing those patients with cardiac risk factors who underwent DSE with those patients with no risk factors and no DSE performed. DSE had a sensitivity of 0.2 and a specificity of 0.9 for myocardial injury. The prevalence of intraoperative hemodynamic instability was significantly higher in patients who had evidence of myocardial injury, but hemodynamic instability was no more common in patients who had a positive DSE.

CONCLUSION

When used in accordance with our protocol a positive DSE does not reliably identify patients at high cardiac risk during liver transplantation, but a negative DSE is strongly predictive of no myocardial injury.

Aprotinin reduces red blood cell transfusion in orthotopic liver transplantation: a prospective, randomized, double-blind study

The effect of an aprotinin infusion on blood and blood product transfusion during adult primary orthotopic liver transplantation (OLT) was investigated in a prospective, randomized, double-blind study. Sixty-three patients were enrolled; 33 patients were administered an aprotinin regimen of a 1,000,000-KIU loading dose, followed by a 250,000-KIU/h infusion during surgery, and 30 patients were administered equivalent volumes of normal saline. Red blood cell (RBC) and blood product transfusion intraoperatively and for the first 24 hours postoperatively was by protocol. Intraoperative coagulation testing and thromboelastography (TEG; Hemoscope Corp, Skokie, IL) were performed. Intraoperative RBC transfusion was significantly less in the aprotinin group versus controls: median, 5 units (interquartile range [IQR], 3 to 9 units) versus 7 units (IQR, 5 to 16 units; P =.0016). No significant differences were found for intraoperative blood product transfusion or transfusion of RBCs or blood products in the 24-hour postoperative period. No significant differences were observed in intraoperative coagulation testing or TEG parameters. We conclude that aprotinin infusion reduces RBC transfusion requirements in OLT.

Liver transplantation for massive hepatic haemangiomatosis causing restrictive lung disease

A 34-yr-old man with hepatic haemangiomatosis presented for orthotopic liver transplantation. His massively distended abdomen caused thoracic compression and severe restrictive lung disease. Respiratory failure was the principal indication for transplantation. Increased airway pressures, pulmonary hypertension, systemic hypotension caused by aorto-caval compression, and blood loss, complicated the intra-operative anaesthetic management. Weaning from mechanical ventilation was impaired by acute and chronic metabolic alkalosis, and diaphragmatic laxity.

Influence of social deprivation on intensive care outcome

OBJECTIVE

To assess the influence of social deprivation on outcome from admission to the intensive care unit.

DESIGN

Retrospective cohort study.

SETTING

Tertiary referral centre mixed adult intensive care unit (ICU).

PATIENTS

Seven hundred seventy-four consecutive admissions to the ICU over a 2-year period.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Age, admission illness severity measured by APACHE II score, predicted hospital mortality, actual hospital mortality and length of ICU stay were obtained for all patients. Social deprivation was assessed by Carstairs Score for postcode sector of residence categorised from 1 (most affluent ) to 7 (most deprived). Carstairs Scores were obtained for 716 patients. When patients in categories 6 and 7 were compared with the others there were no significant differences in age, admission illness severity, predicted or actual hospital mortality and length of ICU stay. On multivariate analysis there was no evidence of an increased mortality risk for patients in categories 6 and 7 (p = 0.256, odds ratio 1.2, 95% confidence interval 0.9-1.7).

CONCLUSIONS

Social deprivation does not influence outcome in patients admitted to the ICU.

Pulmonary hemodynamics and perioperative cardiopulmonary-related mortality in patients with portopulmonary hypertension undergoing liver transplantation

In the setting of moderate to severe pulmonary artery hypertension, orthotopic liver transplantation (OLT) may be complicated by pulmonary hemodynamic instability and cardiopulmonary mortality. We retrospectively studied the relationship between cardiopulmonary-related mortality and initial (untreated) pre-OLT pulmonary hemodynamics in 43 patients with portopulmonary hypertension who underwent attempted OLT. Thirty-six patients were reported in 18 peer-reviewed studies, and 7 patients underwent OLT at our institution since 1996. Transplantation procedure outcome, mean pulmonary artery pressure (MPAP), pulmonary vascular resistance (PVR), cardiac output, pulmonary capillary wedge pressure, and transpulmonary gradient (TPG) are summarized. Overall mortality was reported in 15 of 43 patients (35%). Fourteen of the 15 deaths (93%) were primarily related to cardiopulmonary dysfunction. Two deaths were intraoperative, 8 deaths occurred during the transplantation hospitalization, and 4 patients died of cardiopulmonary deterioration posthospitalization. In 4 patients, the transplantation procedure could not be successfully completed. Cardiopulmonary mortality was associated with greater pre-OLT MPAP (49 +/- 14 v 36 +/- 7 mm Hg; P <.005), PVR (441 +/- 173 v 261 +/- 156 dynes.s.cm(-5); P <.005), and TPG (37 +/- 13 v 22 +/- 10 mm Hg; P <.005). MPAP of 50 mm Hg or greater was associated with 100% cardiopulmonary mortality. In patients with an MPAP of 35 to less than 50 mm Hg and PVR of 250 dynes.s.cm(-5) or greater, the mortality rate was 50%. No mortality was reported in patients with a pre-OLT MPAP less than 35 mm Hg or TPG less than 15 mm Hg. Cardiopulmonary-related mortality in OLT patients with portopulmonary hypertension was frequent and associated with significantly increased pre-OLT MPAP, PVR, and TPG compared with survivors. Treated or untreated, we recommend intraoperative cancellation or advise against proceeding to OLT for an MPAP of 50 mm Hg or greater. Patients with an MPAP of 35 to less than 50 mm Hg and PVR of 250 dynes.s.cm(-5) or greater appear to be at high risk for cardiopulmonary-related mortality after OLT. A prospective study is needed to define optimal pretransplantation treatments and pulmonary hemodynamic criteria that minimize OLT mortality associated with portopulmonary hypertension.

Poor prediction of blood transfusion requirements in adult liver transplantations from preoperative variables

STUDY OBJECTIVE

To assess the ability of preoperative information to predict intraoperative blood transfusion requirements in adult orthotopic liver transplantation.

DESIGN

Retrospective review.

SETTING

Liver transplantation program in a referral center.

PATIENTS

583 sequential adult patients undergoing orthotopic liver transplantation.

MEASUREMENTS

Preoperative variables with a previously demonstrated relationship to intraoperative transfusion were identified from the literature. These variables were then collected retrospectively from 583 consecutive liver transplantations. Relationships between these and intraoperative blood transfusion requirements were examined by both univariate analyses and multiple linear regression analysis.

RESULTS

Univariate analysis revealed significant associations between blood transfused and the following preoperative variables: age, gender, diagnosis, presence of grade 3 or 4 encephalopathy, pseudocholinesterase, creatinine, bilirubin, mean pulmonary artery pressure, activated partial thromboplastin time, and platelet count. Multiple linear regression analysis with correction for diagnosis identified age, creatinine, bilirubin, and pseudocholinesterase as independent predictors; for the final model r(2) = 0.22.

CONCLUSION

Preoperative variables are poor predictors of intraoperative transfusion requirements even when significant associations exist, identifying a small proportion of the variability observed. A predictive approach based on this method would be too inaccurate to be of clinical use. The majority of the variability in transfusion requirements during liver transplantation most likely results from intraoperative and donor organ factors.

Inhaled nitric oxide reduces pulmonary artery pressures in portopulmonary hypertension

Pulmonary artery hypertension in association with liver failure (portopulmonary hypertension [PPHTN]) is a significant barrier to liver transplantation because patients with this condition have a very high mortality when transplantation is undertaken. Inhaled nitric oxide (NO), a potent pulmonary vasodilator, reduces pulmonary artery pressure (PAP) in some patients with primary pulmonary hypertension, but its effect in patients with PPHTN is controversial. We investigated the hemodynamic effects of inhaled NO in 6 patients with PPHTN. Five of 6 patients responded to NO inhalation with decreases in PAP and pulmonary vascular resistance of greater than 10%; these decreases were statistically significant at NO concentrations of 10 and 30 ppm. Cardiac output did not significantly change. We conclude that inhalation of NO reduces PAPs in some patients with PPHTN.

Progressive splenomegaly after epoprostenol therapy in portopulmonary hypertension

Patients with end-stage liver failure, portal hypertension, and associated pulmonary artery hypertension (portopulmonary hypertension [PPHTN]) have a high mortality when undergoing liver transplantation. Successful transplantation in these patients may depend on efforts to reduce pulmonary artery pressure (PAP). To this end, a number of centers are using a continuous intravenous (IV) infusion of epoprostenol, which has been shown to improve symptoms, extend life span, and reduce PAP in patients with primary pulmonary hypertension. We report four cases in which treatment of patients with PPHTN with continuous IV epoprostenol was followed by the development of progressive splenomegaly, with worsening thrombocytopenia and leukopenia. This finding may limit the usefulness of epoprostenol in PPHTN and influence the timing of transplantation in such patients.