Association between vasopressor dependence and early outcome in patients after cardiac 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.

Vasoplegia after heart transplantation: outcomes at 1 year

OBJECTIVES

Vasoplegia syndrome is a potentially life-threatening condition that can occur following cardiopulmonary bypass. Heart transplantation is a recognized risk factor for developing this vasodilatory state. The objective of this study was to determine the effects of vasoplegia syndrome on 1-year heart transplant outcomes.

METHODS

A retrospective review of orthotopic heart transplants at a single institution between November 2010 and December 2014 was performed. Of the 347 consecutive adult patients, 107 patients (30.8%) met criteria for vasoplegia syndrome. Preoperative factors and intraoperative variables were collected and compared between vasoplegia and non-vasoplegia cohorts. The incidence of postoperative complications, transplant rejection and patient survival within 1 year were evaluated.

RESULTS

Demographics and preoperative medication profiles were similar in both groups, while mechanical circulatory support device use was associated with vasoplegia syndrome (30.8% vs 20.0%; P = 0.039). Perioperative characteristics such as longer cardiopulmonary bypass [165.0 (interquartile range [IQR] 74) min vs 140.0 (IQR 42.7) min; P < 0.001] and increased blood product usage (24.7 ± 17.2 units vs 17.7 ± 14.3 units; P < 0.001) were associated with vasoplegia. Non-vasoplegia patients were more likely to be extubated [42.9 (IQR 37.3) h vs 66.8 (IQR 50.2) h; P < 0.001] and discharged earlier [10.0 (IQR 6) days vs 14.0 (IQR 11.5) days; P < 0.001]. One-year patient survival (92.0% vs 88.6%; P = 0.338) and any-treated rejection rates (82.7% vs 84.3%; P = 0.569) were not significantly different between groups.

CONCLUSIONS

Although vasoplegia syndrome was associated with an increase in perioperative morbidity, including greater mechanical ventilation time and hospital length of stay, no significant differences in survival or allograft rejection at 1 year was demonstrated.

Vasopressin versus Norepinephrine in Patients with Vasoplegic Shock after Cardiac Surgery: The VANCS Randomized Controlled Trial

BACKGROUND

Vasoplegic syndrome is a common complication after cardiac surgery and impacts negatively on patient outcomes. The objective of this study was to evaluate whether vasopressin is superior to norepinephrine in reducing postoperative complications in patients with vasoplegic syndrome.

METHODS

This prospective, randomized, double-blind trial was conducted at the Heart Institute, University of Sao Paulo, Sao Paulo, Brazil, between January 2012 and March 2014. Patients with vasoplegic shock (defined as mean arterial pressure less than 65 mmHg resistant to fluid challenge and cardiac index greater than 2.2 l · min · m) after cardiac surgery were randomized to receive vasopressin (0.01 to 0.06 U/min) or norepinephrine (10 to 60 μg/min) to maintain arterial pressure. The primary endpoint was a composite of mortality or severe complications (stroke, requirement for mechanical ventilation for longer than 48 h, deep sternal wound infection, reoperation, or acute renal failure) within 30 days.

RESULTS

A total of 330 patients were randomized, and 300 were infused with one of the study drugs (vasopressin, 149; norepinephrine, 151). The primary outcome occurred in 32% of the vasopressin patients and in 49% of the norepinephrine patients (unadjusted hazard ratio, 0.55; 95% CI, 0.38 to 0.80; P = 0.0014). Regarding adverse events, the authors found a lower occurrence of atrial fibrillation in the vasopressin group (63.8% vs. 82.1%; P = 0.0004) and no difference between groups in the rates of digital ischemia, mesenteric ischemia, hyponatremia, and myocardial infarction.

CONCLUSIONS

The authors' results suggest that vasopressin can be used as a first-line vasopressor agent in postcardiac surgery vasoplegic shock and improves clinical outcomes.

Bispectral index guided titration of sevoflurane in on-pump cardiac surgery reduces plasma sevoflurane concentration and vasopressor requirements: a prospective, controlled, sequential two-arm clinical study

BACKGROUND

Electroencephalographic-based monitoring systems such as the bispectral index (BIS) may reduce anaesthetic overdose rates.

OBJECTIVE

We hypothesised that goal-directed sevoflurane administration (guided by BIS monitoring) could reduce the sevoflurane plasma concentration (SPC) and intraoperative vasopressor doses during on-pump cardiac surgery.

DESIGN

A prospective, controlled, sequential two-arm clinical study.

SETTING

German university medical centre with more than 2500 cardiac surgery interventions per year.

PATIENTS

Sixty elective on-pump cardiac surgery patients.

INTERVENTION

In group Sevo1.8% (n = 29), the sedation depth was maintained with a sustained inspired concentration of sevoflurane 1.8% before and during cardiopulmonary bypass (CPB). In group SevoBIS (n = 31), the inspired sevoflurane concentration was titrated to maintain a BIS target between 40 and 60.

OUTCOME MEASURES

SPC during CPB and the intraoperative administration of noradrenaline. Additional analyses were performed on intraoperative awareness, postoperative blood lactate concentration, duration of mechanical ventilation, intensive care unit length of stay and kidney injury.

RESULTS

Mean inspired sevoflurane concentration was 0.8% in group SevoBIS, representing a 57.1% reduction (P < 0.001) compared with group Sevo1.8%. The mean SPC was 42.3 μg ml(-1) [95% confidence interval (CI) 40.0 to 44.6] in group Sevo1.8% and 21.0 μg ml(-1) (95% CI 18.8 to 23.3) in group SevoBIS, representing a 50.2% reduction (P < 0.001). During CPB, the mean cumulative dose of noradrenaline administered was 13.48 μg kg(-1) (95% CI 10.52 to 17.19) in group Sevo1.8% and 4.06 μg kg(-1) (95% CI 2.67 to 5.97) in group SevoBIS (P < 0.001). Pearson's correlation coefficient (between the cumulative applied dosage of sevoflurane calculated from the area under the curve of the SPC over time and the administered cumulative noradrenaline dose) was 0.607 (P < 0.001). No intraoperative awareness signs were detected.

CONCLUSION

BIS-guided titration of sevoflurane reduces the SPC and decreases noradrenaline administration compared with routine care during on-pump cardiac surgery.

Catecholamine and volume therapy for cardiac surgery in Germany--results from a postal survey

BACKGROUND

Management of cardiac surgery patients is a very standardized procedure in respective local institutions. Yet only very limited evidence exists concerning optimal indication, safety and efficacy of hemodynamic monitoring catecholamine and fluid therapy.

METHODS

Between April and May 2013, all 81 German anaesthesia departments involved in cardiac surgery care were asked to participate in a questionnaire addressing the institutional specific current practice in hemodynamic monitoring, catecholamine and volume therapy.

RESULTS

51 (63%) questionnaires were completed and returned. All participating centers used basic hemodynamic monitoring (i.e. invasive arterial blood pressure and central venous pressure), supplemented by transesophageal echocardiography. Pulmonary arterial catheter and calibrated trend monitoring devices were also routinely available. In contrast, non-calibrated trend monitoring and esophageal doppler ultrasound devices were not commonly in use. Cerebral oximetry is increasingly emerging, but lacks clear indications. The majority of patients undergoing cardiac surgery, especially in university hospitals, required catecholamines during perioperative care, In case of low cardiac output syndrome, dobutamine (32%), epinephrine (30%) or phosphodiesterase inhibitors (8%) were first choice. In case of hypotension following vasoplegia, norepinephrine (96%) represented the most common catecholamine. 88% of the participating centers reported regular use of colloid fluids, with hydroxyethyl starches (HES) being first choice (64%).

CONCLUSIONS

Choice of hemodynamic monitoring is homogenous throughout German centers treating cardiac surgery patients. Norepinephrine is the first line catecholamine in cases of decrease in peripheral vascular resistance. However, catecholamine choice for low cardiac output syndrome varies considerably. HES was the primary colloid used for fluid resuscitation. After conduct of this survey, HES use was restricted by European regulatory authorities in critically ill patients and should only be considered as second-line fluid in surgical patients without renal impairment or severe coagulopathy. Large clinical studies addressing catecholamine and fluid therapy in cardiac surgery patients are lacking.

Custodiol for myocardial protection and preservation: a systematic review

INTRODUCTION

Custodiol cardioplegia is attractive for minimally invasive cardiac surgery, as a single dose provides a long period of myocardial protection. Despite widespread use in Europe, there is little data confirming its efficacy compared with conventional (blood or crystalloid) cardioplegia. There is similar enthusiasm for its use in organ preservation for transplant, but also a lack of data. This systematic review aimed to assess the evidence for the efficacy of Custodiol in myocardial protection and as a preservation solution in heart transplant.

METHODS

Electronic searches were performed of six databases from inception to October 2013. Reviewers independently identified studies that compared Custodiol with conventional cardioplegia (blood or extracellular crystalloid) in adult patients for meta-analysis; large case series that reported results using Custodiol were analyzed. Next, we identified studies that compared Custodiol with other organ preservation solutions for organ preservation in heart transplant.

RESULTS

Fourteen studies compared Custodiol with conventional cardioplegia for myocardial protection in adult cardiac surgery. No difference was identified in mortality; there was a trend for increased incidence of ventricular fibrillation in the Custodiol group that did not reach statistical significance. No difference was identified in studies that compared Custodiol with other solutions for heart transplant.

CONCLUSIONS

Despite widespread clinical use, the evidence supporting the superiority of Custodiol over other solutions for myocardial protection or organ preservation is limited. Large randomised trials are required.

[Factors involved in the development of vasoplegia after cardiac surgery with extracorporeal circulation. A prospective observational study]

OBJECTIVE

The incidence and risk factors for vasoplegia in the early postoperative period and at 24h are investigated in patients subjected to cardiopulmonary bypass surgery. Vasoplegia following cardiac surgery with cardiopulmonary bypass is associated with a high morbimortality. The risk factors described emerged from retrospective, non-controlled studies.

METHODS

Observational prospective study of 188 consecutive patients subjected to cardiac surgery with cardiopulmonary bypass in a single hospital between November 2011 and May 2012. Emergency surgery or complex procedures were excluded. Vasoplegia was assessed during the immediate postoperative period, and at 24h after surgery, and was defined as a mean arterial pressure below 50mmHg, and the need for a noradrenaline perfusion of more than 0.08μg/kg/min, monitored by cardiac output and systemic vascular resistances. The anaesthetic and cardiopulmonary bypass protocols, as well as haemodynamic management, were the same in all patients.

RESULTS

Almost half (48%) of patients had vasoplegia in the immediate postoperative period, and 34% at 24h. Risk factors for immediate vasoplegia development were preoperative use of angiotensin converting enzyme inhibitor drugs, a mean arterial pressure<50mmHg immediately after beginning cardiopulmonary bypass, duration of aortic clamping as well as the cardiopulmonary bypass, and minimum temperature in cardiopulmonary bypass. Vasoplegia at 24h after surgery was correlated to preoperative angiotensin converting enzyme inhibitor drug treatment and cardiopulmonary bypass duration.

CONCLUSION

The incidence of vasoplegia after cardiac surgery with cardiopulmonary bypass is high during the first 24 postoperative hours. Preoperative treatment with angiotensin converting enzyme inhibitor and the mean arterial pressure at the beginning of cardiopulmonary bypass are the more easily controllable risk factors. In patients arriving to surgery with those drugs, treatment or prevention of vasoplejia should be planned.

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.

Rapid decline in 51Cr-EDTA measured renal function during the first weeks following lung transplantation

We previously described a 54% decline in renal function at 6 months after lung transplantation (LTx). We hypothesized that this decline is a very early event following LTx. Thirty-one consecutive patients (16 females/15 males), mean age 49 (+/-13) years, with emphysema, cystic fibrosis/bronchiectasis or idiopathic pulmonary fibrosis were included in an analysis of renal function before and after LTx. The glomerular filtration rate (GFR) was measured using the (51)Cr-ethylenediaminetetra acetic acid plasma clearance single injection technique (mGFR) at baseline before transplantation and at 1, 2, 3 and 12 weeks postoperatively. Mean mGFR declined from 103 +/- 18 to 65 +/- 22, 53 +/- 16 and 57 +/- 18 mL/min/1.73m(2) at 1-, 3- and 12-weeks post-LTx (p < 0.0001), respectively. In a time-dependent repeated measures ANOVA, risk factors for a decline in mGFR posttransplant included: time (p < 0.0001), acute renal failure within 2 weeks post-LTx (p = 0.0003), use of heart and lung machine (p = 0.04), and the use of ephedrine (p = 0.048), as well as increasing age, older than 18 years at LTx (p = 0.006). These data demonstrate that renal function, measured with an isotope method, decreases dramatically during the first week after LTx.

[Corticosteroid insufficiency in the critically ill. Pathomechanisms and recommendations for diagnosis and treatment]

Critically ill patients with severe systemic inflammation can develop critical illness-related corticosteroid insufficiency (CIRCI), which is associated with a poor outcome. A task force of the American College of Critical Care Medicine compiled recommendations for diagnosis and treatment of this clinical entity thereby focusing on patients with septic shock and acute respiratory distress syndrome (ARDS). The results of large scale multi-centre trials gave partially conflicting results arguing against the broad use of corticosteroids in stress doses. However, the task force recommended treatment with stress-dose corticosteroids in patients with septic shock who respond poorly to fluid resuscitation and vasopressor therapy and in patients with early ARDS (<14 days after onset). The dose of corticosteroids should be reduced in a step-wise manner. Corticosteroids at stress doses are currently under investigation in other target populations of critically ill patients potentially suffering from CIRCI. Preliminary data suggest that patients with vasodilatory shock after cardiac surgery and patients with liver cirrhosis and sepsis can benefit from corticosteroids. Critical illness-related corticosteroid insufficiency can also occur in patients with trauma, traumatic brain injury, acute pancreatitis and burn injuries, but data from clinical trials on these target groups are insufficient at present. The therapeutic use of corticosteroids in stress doses reduces the incidence of post-traumatic stress disorder (PTSD) after intensive care treatment.

Stress doses of hydrocortisone in high-risk patients undergoing cardiac surgery: effects on interleukin-6 to interleukin-10 ratio and early outcome

BACKGROUND

Severe systemic inflammation (systemic inflammatory response syndrome) associated with cardiac surgery often leads to a worse short-term and long-term outcome. Stress doses of hydrocortisone have been successfully used to improve outcome of CS. The interleukin (IL)-6 to IL-10 ratio is associated with outcome after trauma and major surgery.

OBJECTIVE

To evaluate immunologic effects (especially IL-6 to IL-10 ratio) of stress doses of hydrocortisone in a high-risk group of patients after cardiac surgery with cardiopulmonary bypass.

DESIGN

Prospective, randomized, double-blinded, placebo-controlled trial.

SETTING

Cardiovascular intensive care unit of a university hospital.

PATIENTS

High-risk patients (n = 36) undergoing CS.

INTERVENTION

Stress doses of hydrocortisone or placebo.

MAIN OUTCOME MEASURES

IL-6 to IL-10 ratio and other markers of systemic inflammation at predefined time points; short-term clinical outcome.

RESULTS

The two study groups did not differ with regard to demographic data. The patients from the hydrocortisone group (n = 19) had significantly lower levels of IL-6 and higher levels of IL-10, resulting in an attenuated change in IL-6/IL-10 ratio (28.7 [6.4/128.7] vs. 292.8 [6.5/534.6] 4 hours after cardiopulmonary bypass; p < 0.001). Patients in the hydrocortisone group had a shorter duration of catecholamine support (1 [1/2] vs. 4 [2/4.5] days; p = 0.02), a shorter length of stay in the intensive care unit (2 [2/3] vs. 6 [4/8] days; p = 0.001), and a lower incidence of postoperative atrial fibrillation (26% vs. 59%; p = 0.04).

CONCLUSIONS

Stress doses of hydrocortisone attenuate the evolution of IL-6/IL-10 ratio in patients with systemic inflammatory response syndrome after CS, which seems to be associated with an improved outcome. The immunologic effects of hydrocortisone may thus be both, inhibitory (IL-6) and permissive (IL-10), regarding the immune response.

Indications and practical use of replacement dose of corticosteroids in critical illness

PURPOSE OF REVIEW

Ongoing and severe systemic inflammation affecting critically ill patients may cause adrenal insufficiency and steroid resistance in target cells. As the appropriate diagnosis of this clinical entity remains a challenge, indication and practical use of corticosteroid replacement therapy in the critically ill is generally directed by clinical symptoms and features.

RECENT FINDINGS

In the last 2 years, a series of clinical trials have been undertaken to investigate corticosteroid replacement therapy in critically ill patients with severe systemic inflammation of various origin. Improvements of morbidity have been demonstrated in some studies. The data of recent studies should lead to a restriction of corticosteroid replacement therapy in critically ill patients. The purpose of this review is to investigate indications and the best current practical use of corticosteroid replacement therapy in critically ill patients in the absence of accurate laboratory assessment of adrenal insufficiency.

SUMMARY

Corticosteroid replacement therapy may improve morbidity and mortality in specific target groups of critically ill patients. The appropriate target groups remain to be refined. To demonstrate this, additional studies are required on endocrine disorder in critical illness and corticosteroid replacement therapy.