Factors That Predict the Use of Positive Inotropic Drug Support After Cardiac Valve Surgery

The Role of Perioperative Levosimendan in Patients with Reduced Ejection Fraction undergoing Cardiac surgery in Reducing Post-operative Hemodynamic Support

BACKGROUND: Acute perioperative left ventricular dysfunction is a major complication affecting patients subjected to cardiac surgery and is associated with increased mortality. Levosimendan as a “calcium sensitizers” with inodilator effect improves myocardial contractility by sensitizing troponin C to calcium without increasing myocardial oxygen consumption and without impairing relaxation and diastolic function. AIM: The aim of this study was to evaluate the effect of perioperative levosimendan compared to the conventional management used in the patient with poor left ventricular function undergoing cardiac surgery to reduce the need of post-operative pharmacological and mechanical circulatory support. METHODS: It is prospective observational studies were patients undergoing cardiac surgery divided into two groups of 25 patients each. The first group received conventional management while the other group received levosimendan additionally duration and type of post-operative pharmacological support, duration of mechanical ventilation, durations of ICU and hospital stays, and major outcomes, and data about the need of mechanical support were collected. RESULTS: In the levosimendan, fewer patients required vasoactive agents post-surgery (Noradrenaline) compared to the conventional group, yet the use of inotropic support (adrenaline) in the 2nd day and the need of mechanical circulatory support was equal in both groups. The mortality was equal in both groups. CONCLUSION: Perioperative levosimendan may reduce the need of vasoactive agents postoperatively, but it does not reduce the need of inotropic nor mechanical support.

Beneficial effects of levosimendan on survival in patients undergoing extracorporeal membrane oxygenation after cardiovascular surgery

BACKGROUND

The impact of levosimendan treatment on clinical outcome in patients undergoing extracorporeal membrane oxygenation (ECMO) support after cardiovascular surgery is unknown. We hypothesized that the beneficial effects of levosimendan might improve survival when adequate end-organ perfusion is ensured by concomitant ECMO therapy. We therefore studied the impact of levosimendan treatment on survival and failure of ECMO weaning in patients after cardiovascular surgery.

METHODS

We enrolled a total of 240 patients undergoing veno-arterial ECMO therapy after cardiovascular surgery at a university-affiliated tertiary care centre into our observational single-centre registry.

RESULTS

During a median follow-up period of 37 months (interquartile range 19-67 months), 65% of patients died. Seventy-five per cent of patients received levosimendan treatment within the first 24 h after initiation of ECMO therapy. Cox regression analysis showed an association between levosimendan treatment and successful ECMO weaning [adjusted hazard ratio (HR) 0.41; 95% confience interval (CI) 0.22-0.80; P=0.008], 30 day mortality (adjusted HR 0.52; 95% CI 0.30-0.89; P=0.016), and long-term mortality (adjusted HR 0.64; 95% CI 0.42-0.98; P=0.04).

CONCLUSIONS

These data suggest an association between levosimendan treatment and improved short- and long-term survival in patients undergoing ECMO support after cardiovascular surgery.

Intraoperative milrinone versus dobutamine in cardiac surgery patients: a retrospective cohort study on mortality

Background

Several choices of inotropic therapy are available and used in relation to cardiac surgery. Comparisons are necessary to select optimal therapy. In Denmark, dobutamine and milrinone are the two inotropic agents most commonly used to treat post-bypass low cardiac output syndrome. This study compares all-cause mortality with these drugs.

Methods

In a retrospective observational study we investigated 10,700 consecutive patients undergoing cardiac surgery from 1 April 2006 to 31 December 2013 at Aarhus and Aalborg University Hospitals in the Central and Northern Denmark Region. Prospectively entered data in the Western Danish Heart Registry on intraoperative use of inotropes were used to identify 952 patients treated with milrinone, 418 patients treated with dobutamine, and 82 patients receiving a combination of the two inotropes. All-cause mortality among patients receiving dobutamine was compared to all-cause mortality among milrinone receivers.

Multiple logistic regression analyses including preoperative and intraoperative variables along with g-formula analyses were used to model 30-day and 1-year mortality risks. Reported were standardized mortality risk differences between the treatment groups.

Results

Among patients receiving intraoperative dobutamine, 18 (4.3%) died within 30 days and 49 (11.7%) within 1 year. Corresponding 30-day and 1-year mortality for milrinone receivers were 81 (8.5%) and 170 (17.9%). Risk of death within 30 days and 1 year was increased for intraoperative milrinone compared to dobutamine with a standardized risk difference of 4.06% (confidence interval (CI) 1.23; 6.89, p = 0.005) and 4.77% (CI 0.39; 9.15, p = 0.033), respectively. Sensitivity analyses including adjustment for milrinone preference, hemodynamic instability prior to cardiopulmonary bypass, and separate analyses on hospital level all confirmed a sign toward increased mortality among milrinone receivers.

Conclusions

Intraoperative use of milrinone in cardiac surgery may be associated with an increase in all-cause mortality compared to use of dobutamine.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-1969-1) contains supplementary material, which is available to authorized users.

Outcome of cardiac surgery in patients with low preoperative ejection fraction

Background

In patients undergoing cardiac surgery, a reduced preoperative left ventricular ejection fraction (LVEF) is common and is associated with a worse outcome. Available outcome data for these patients address specific surgical procedures, mainly coronary artery bypass graft (CABG). Aim of our study was to investigate perioperative outcome of surgery on patients with low pre-operative LVEF undergoing a broad range of cardiac surgical procedures.

Methods

Data from patients with pre-operative LVEF ≤40 % undergoing cardiac surgery at a university hospital were reviewed and analyzed. A subgroup analysis on patients with pre-operative LVEF ≤30 % was also performed.

Results

A total of 7313 patients underwent cardiac surgery during the study period. Out of these, 781 patients (11 %) had a pre-operative LVEF ≤40 % and were included in the analysis. Mean pre-operative LVEF was 33.9 ± 6.1 % and in 290 patients (37 %) LVEF was ≤30 %. The most frequently performed operation was CABG (31 % of procedures), followed by mitral valve surgery (22 %) and aortic valve surgery (19 %). Overall perioperative mortality was 5.6 %. Mitral valve surgery was more frequent among patients who did not survive, while survivors underwent more frequently CABG. Post-operative myocardial infarction occurred in 19 (2.4 %) of patients, low cardiac output syndrome in 271 (35 %). Acute kidney injury occurred in 195 (25 %) of patients. Duration of mechanical ventilation was 18 (12–48) hours. Incidence of complications was higher in patients with LVEF ≤30 %. Stepwise multivariate analysis identified chronic obstructive pulmonary disease, pre-operative insertion of intra-aortic balloon pump, and pre-operative need for inotropes as independent predictors of mortality among patients with LVEF ≤40 %.

Conclusions

We confirmed that patients with low pre-operative LVEF undergoing cardiac surgery are at higher risk of post-operative complications. Cardiac surgery can be performed with acceptable mortality rates; however, mitral valve surgery, was found to be associated with higher mortality rates in this population. Accurate selection of patients, risk/benefit evaluation, and planning of surgical and anesthesiological management are mandatory to improve outcome.

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-016-0271-5) contains supplementary material, which is available to authorized users.

Initial Perioperative Care of the Cardiac Surgical Patient

Recently, changes in the management of cardiac patients have allowed earlier discharge from the cardiac recovery area and reduced hospital length of stay. These changes have been drien by a need to reduce the cost of cardiac surgery and imrove efficiency. This change has been both financially sucessful and safe for patients. To allow for this success, a joint effort is required between the departments of cardiac surgery and anesthesiology involving the preoperative, intraoperative and postoperative treatment of these patients. Through recogition of suitable candidates, modifications in anesthetic techique, and appropriate postoperative management, the goal of extubation within 6 hours of admission to the cardiac recovery area can be achieved. Changes in intraoperative and early postoperative management of cardiac surgical patients are discussed. Specific recovery models are reviewed with disussion of the parallel and integrated models. Methods of preicting prolonged extubation times and intensive care unit length of stay are also discussed. Initial management of the cardiac patient in the cardiac recovery area is presented with a more in-depth review of specific complications: stroke, atril fibrillation, blood loss, left ventricular dysfunction, and pulonary dysfunction.

Liver function predicts survival in patients undergoing extracorporeal membrane oxygenation following cardiovascular surgery

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) represents a valuable and rapidly evolving therapeutic option in patients with severe heart or lung failure following cardiovascular surgery. However, despite significant advances in ECMO techniques and management, prognosis remains poor and accurate risk stratification challenging. We therefore evaluated the predictive value of liver function variables on all-cause mortality in patients undergoing venoarterial ECMO support after cardiovascular surgery.

METHODS

We included into our single-center registry a total of 240 patients undergoing venoarterial ECMO therapy following cardiovascular surgery at a university-affiliated tertiary care center.

RESULTS

The median follow-up was 37 months (interquartile range 19-67 months), and a total of 156 patients (65%) died. Alkaline phosphatase and total bilirubin were the strongest predictors for 30-day mortality, with adjusted hazard ratios (HRs) per 1-standard deviation increase of 1.36 (95% confidence interval [CI] 1.10-1.68; P = 0.004) and 1.22 (95% CI 1.07-1.40; P = 0.004), respectively. The observed associations persisted for long-term mortality, with adjusted HRs of 1.27 (95% CI 1.03-1.56; P = 0.023) for alkaline phosphatase and 1.22 (95% CI 1.07-1.39; P = 0.003) for total bilirubin.

CONCLUSIONS

The present study demonstrates that elevated values of alkaline phosphatase and total bilirubin are sensitive parameters for predicting the short-term and long-term outcomes of ECMO patients.

Postoperative inotrope and vasopressor use following CABG: outcome data from the CAPS-care study

BACKGROUND/AIM

Limited clinical data exist to guide practice patterns and evidence-based use of inotropes and vasopressors following coronary artery bypass grafting (CABG).

METHODS

Contemporary Analysis of Perioperative Cardiovascular Surgical Care (CAPS-Care) collected detailed perioperative data from 2390 CABG patients between 2004 and 2005 at 55 U.S. hospitals. High-risk elective or urgent CABG patients were eligible for inclusion. We stratified participating hospitals into high, medium, and low tertiles of inotrope use. Hospital-level outcomes were compared before and after risk adjustment for baseline characteristics.

RESULTS

Hospital-level risk-adjusted rates of any inotrope/vasopressor use varied from 100% to 35%. Hospitals in the highest tertile of use had more patients with mitral regurgitation compared to medium- or low-use hospitals (p < 0.001), more previous cardiovascular interventions (p = 0.002), longer cardiopulmonary bypass (p < 0.001), longer cross-clamp times (p < 0.001), and required more transfusions (p = 0.001). Despite these differences, unadjusted outcomes were similar between high-, medium-, and low-use hospitals for operative mortality (4.5% vs. 5.3% vs. 5.2%; p = 0.702), 30-day mortality (4.1% vs. 4.6% vs. 5.0%; p = 0.690), postoperative renal failure (7.2% vs. 9.2% vs. 6.6%; p = 0.142), atrial fibrillation (23.0% vs. 27.2% vs. 25.6%; p = 0.106), and acute limb ischemia (0.6% vs. 0.5% vs. 0.5%; p = 0.945). These similar outcomes persisted after risk adjustment: adjusted OR = 0.97 (95% CI [0.94, 1.00], p = 0.086) for operative mortality and adjusted OR = 1.00 (95% CI [0.96, 1.04], p = 0.974) for postoperative renal failure.

CONCLUSION

While considerable variability is present among hospitals in inotrope use following CABG, observational comparison of outcomes did not distinguish a superior pattern; thus, randomized prospective data are needed to better guide clinical practice.

Intraoperative Hemodynamic Instability During and After Separation From Cardiopulmonary Bypass

Every year, more than 1 million patients worldwide undergo cardiac surgery. Because of the aging of the population, cardiac surgery will increasingly be offered to patients at a higher risk of complications. The consequence is a reduced physiological reserve and hence an increased risk of mortality. These issues will have a significant impact on future health care costs because the population undergoing cardiac surgery will be older and more likely to develop postoperative complications. One of the most dreaded complications in cardiac surgery is difficult separation from cardiopulmonary bypass (CPB). When separation from CPB is associated with right-ventricular failure, the mortality rate will range from 44% to 86%. Therefore, the diagnosis and the preoperative prediction of difficult separation from CPB will be crucial to improve the selection and care of patients and to prevent complications for this high-risk patient population.

In patients chronically treated with metoprolol, the demand of inotropic catecholamine support after coronary artery bypass grafting is determined by the Arg389Gly-β1-adrenoceptor polymorphism

In vitro, the Arg389Gly-beta(1)-adrenoceptor (AR) polymorphism exhibits decreased receptor signaling. In vivo, dobutamine infusion evoked smaller heart rate and/or contractility increases in subjects carrying Gly389Gly-beta(1)AR vs subjects carrying Arg389Arg-beta(1)AR. The aim of this study was to find out whether the Arg389Gly-beta(1)AR polymorphism might also determine demand of catecholamine-induced inotropic support in patients with low cardiac index (CI) after coronary artery bypass grafting (CABG) surgery with cardiopulmonary bypass (CPB). For this purpose, we assessed in 82 patients, who were preoperatively chronically treated with metoprolol, after CABG surgery with CPB, the dose and duration of adrenaline-induced inotropic support in relation to the Arg389Gly-beta(1)AR genotype. Patients homozygous for the Arg389-beta(1)AR variant (n = 45) required, in comparison to patients homozygous for the Gly389-beta(1)AR variant (n = 9), lower adrenaline doses (53 +/- 24 vs 164 +/- 39 ng/kg body weight/min, p < 0.05) to reach a stable and comparable hemodynamic status and a CI >or= 3.0 l/min/m(2). Moreover, the time necessary for inotropic support tended to be shorter in patients homozygous for the Arg389-beta(1)AR than in patients homozygous for the Gly389-beta(1)AR (10.5 +/- 6 vs 20.5 +/- 12 h). Values for patients heterozygous for the Arg389Gly-beta(1)AR (n = 28) were in between. We conclude that the Arg389Gly-beta(1)AR polymorphism appears to be a determinant of cardiac responses to catecholamine stimulation. Thus, by assessment of the Arg389Gly-beta(1)AR polymorphism, it might be possible to predict demand of and therapeutic responses to beta AR agonist treatment.

Incidence and significance of abnormal hepatic venous Doppler flow velocities before cardiac surgery

OBJECTIVE

The purpose of this study was to determine the incidence and significance of abnormal hepatic Doppler venous flow velocities as signs of an abnormal right ventricular filling pattern before cardiac surgery.

DESIGN

Retrospective and prospective validation study.

SETTING

Tertiary care hospital.

PARTICIPANTS

Cardiac surgical patients (121 patients).

INTERVENTIONS

Not applicable.

MEASUREMENTS

Demographic, hemodynamic, and echocardiographic variables; vasoactive support; and difficult separation from bypass were compared between patients with or without abnormal hepatic venous Doppler flow. Logistic regression analysis was performed to identify predictors of difficult separation from bypass. Abnormal hepatic venous flow was observed in 23 (29%) and 17 patients (41%) in the retrospective and prospective study. Abnormal hepatic venous flow before surgery was associated with more vasoactive support in both the retrospective (p = 0.0362) and prospective study (p = 0.0163). In the prospective study, abnormal hepatic venous flow was associated with a higher Parsonnet score (p = 0.0005), more atrial fibrillation (p < 0.0001), pacemaker requirement (p = 0.0124), mitral valve replacement (p = 0.0325), reoperation (p = 0.0050), lower mean arterial pressure to pulmonary artery pressure ratio (p = 0.0127), higher wall motion score index (p = 0.0491), and higher incidence of abnormal right ventricular systolic function (p = 0.0139). Abnormal hepatic venous flow was not found to be an independent predictor of difficult separation from bypass.

CONCLUSIONS

Abnormal hepatic venous flow velocities before cardiac surgery are frequent and are associated with increased need for vasoactive support after cardiopulmonary bypass. However, it is not an independent predictor of difficult separation from bypass and worse outcome.

Intraoperative regional myocardial acidosis predicts the need for inotropic support in cardiac surgery

OBJECTIVE

To determine the impact of regional myocardial acidosis encountered during cardiac surgery on the need for inotropic and intra-aortic balloon (IAB) support.

METHODS

Intramyocardial tissue pH(37C) was measured in 247 patients undergoing cardiopulmonary bypass (CPB). Inotropic support (INO) was defined as requiring one or more of norepinephrine/epinephrine/amrinone/dobutamine/>2.5 mug/kg/min dopamine, for at least 45 minutes intraoperatively, and intraoperative or postoperative IAB use. PH (corrected to 37 degrees C, pH(37C)) during surgery was compared in patients who needed INO versus those who did not. Multivariate logistic regression models identified the determinants of INO.

RESULTS

Fifty patients (20.2%) required INO intraoperatively. pH(37C) was significantly lower throughout reperfusion in patients needing INO. Preoperative ejection fraction and pH(37C) during reperfusion were identified as independent predictors of INO.

CONCLUSIONS

This is the first study to show that intraoperative regional myocardial acidosis, a preventable condition, independently determines the need for intraoperative INO. Increased INO is associated with greater postoperative mortality and morbidity.

Predictors of inotrope use during separation from cardiopulmonary bypass

OBJECTIVE

To identify the demographic, clinical, and echocardiographic features that predict the use of inotropic support at separation from cardiopulmonary bypass (CPB).

DESIGN

Retrospective study of consecutive patients undergoing coronary artery bypass graft (CABG) surgery.

SETTING

Referral center for cardiothoracic surgery at a university hospital.

PARTICIPANTS

One thousand nine patients undergoing either CABG or combined CABG and valve surgery with CPB in whom an intraoperative transesophageal echocardiography (TEE) examination was performed.

INTERVENTIONS

Inotropic support was defined as the use of dopamine >/=5 microg/kg/min; any dose of epinephrine, norepinephrine, dobutamine, and milrinone; or the insertion of an IABP during separation from CPB. Support was implemented by the anesthesia care team as clinically indicated. Comprehensive TEE examinations were conducted before CPB in all patients according to published guidelines and subsequently reviewed by a single, independent operator.

MEASUREMENTS AND MAIN RESULTS

Inotropic support was used in a total of 394 patients (39%) at separation from CPB. The study identified 6 significant, independent predictors of inotrope use: (1) Wall Motion Score Index, (2) combined CABG and mitral valve repair or replacement surgery, (3) left ventricular ejection fraction <35%, (4) reoperation, (5) moderate-to-severe mitral regurgitation, and (6) aortic cross-clamp time.

CONCLUSIONS

Incorporating data from a comprehensive intraoperative TEE examination, the authors identified 6 reproducible factors that independently predict the use of inotropic support at separation from CPB.

Interleukin-8 secretion following cardiopulmonary bypass in children as a marker of early postoperative morbidity

BACKGROUND

Interleukin (IL)-8, an 8 kDa peptide, is the first chemoattractant identified as being specific for neutrophils. Its possible association with early postoperative morbidity following cardiopulmonary bypass (CPB) in infants and children is unknown. This prospective cohort study sought possible roles of IL-8 in the inflammatory response to CPB and investigated if changes in IL-8 levels and clinical course and outcome were related.

METHODS

IL-8 levels were measured in 16 children undergoing CPB. Systemic blood was collected after induction of anaesthesia (baseline), at 15 min after CPB onset and cessation, and at 1, 4, 8, 12 and 24 h thereafter.

RESULTS

Correlation coefficients between IL-8 levels and CPB time ranged from 0.45 to 0.55, heart rate 0.41--0.44, surgical time 0.41--0.63 and pH --0.56 to --0.50 (P < 0.05 for all parameters). Univariate analyses showed that patients requiring inotropic support and those with tachycardia had significantly higher postoperative IL-8 levels (P < 0.05). Furthermore, IL-8 levels were significantly higher in patients with surgical times > 200 min and in patients with an aortic clamp in place for > 65 min.

CONCLUSIONS

There was an association between IL-8 and early postoperative heart rate, and the need for inotropic support IL-8 correlated positively with surgical time, CPB time and heart rate and negatively with pH. IL-8 release may be related to some of the haemodynamic changes in the early postoperative course following CPB. The relationship between IL-8 and late markers of patient outcome in high-risk infants awaits further studies.

Management of perioperative ventricular dysfunction

With the recognition of the clinical importance of the right ventricle; the development of new techniques for the perioperative evaluation of RV function, particularly transesophageal echocardiography; and new treatment modalities (pharmacologic and mechanical), clinicians will be able to more accurately diagnose and precisely manage patients who have sustained RV injury.

Plasma-soluble E-selectin after cardiopulmonary bypass in children: is it a marker of the postoperative course?

OBJECTIVE

To investigate the relationship and possible role of soluble adhesion molecule E-selectin in the postoperative course in children undergoing cardiopulmonary bypass (CPB).

DESIGN

Prospective cohort study.

SETTING

Pediatric intensive care unit of a university hospital.

PARTICIPANTS

Thirteen children who were candidates for cardiac surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Serial blood samples of 13 CPB patients were collected from the arterial catheter or from the bypass circuits preoperatively; on initiation of CPB; on termination of CPB; and 1, 2, 4, 8, 12, 18, 24, and 48 hours postoperatively. Plasma was recovered immediately, aliquoted, and frozen at -70 degrees C until use. Circulating soluble selectin molecules were measured with a sandwich enzyme-linked immunosorbent assay technique. There were significant changes in plasma levels of soluble E-selectins in patients after CPB, and these levels were associated with patient characteristics, operative variables, and postoperative course. Soluble E-selectin correlated significantly with inotropic support and the use of anti-inflammatory drugs. There was a significant association between the development of postoperative sepsis and soluble E-selectin levels. No correlation was found between soluble E-selectins and duration of CPB, aortic cross-clamping, or hemodynamic variables, including heart rate and mean systemic arterial pressure.

CONCLUSION

These results suggest a relationship between CPB-induced mediators and early and late clinical effects. Although the mechanism for the increase of soluble E-selectin remains to be elucidated, the upregulation of soluble E-selectin indicates neutrophil activation, and its inhibition may represent a target for reducing the inflammatory response associated with CPB.