Levosimendan for resuscitating the microcirculation in patients with septic shock: a randomized controlled study

Levosimendan does not provide mortality benefit over dobutamine in adult patients with septic shock: A meta-analysis of randomized controlled trials

OBJECTIVES

Despite of advancement in intensive care medicine, sepsis and septic shock carry a high mortality. Levosimendan, an inodilator, may be promising for septic shock patients with myocardial dysfunction; however, firm evidence is lacking. In this meta- analysis of randomized controlled trials, levosimendan has been compared with dobutamine in adult patients with sepsis and septic shock.

DESIGN

Meta-analysis of randomized controlled trial.

SETTING

Intensive-care unit.

PARTICIPANTS

Adult septic shock patients.

INTERVENTION

Adult septic shock patients received dobutamine or levosimendan.

MAIN OUTCOME MEASURE

Mortality at longest follow-up, blood lactate level, cardiac index and noradrenaline requirement.

RESULTS

Data from 7 randomized trials have been included in this meta-analysis. Levosimendan has no benefit in terms of mortality at longest follow up in comparison to dobutamine (Odds ratio 0.77, 95% CI 0.45, 132; p=0.34) and length of ICU stay (MD -4.7days, 95% CI -10.3, 0.9days, p=0.10). Patients received levosimendan had less blood lactate level (standardized mean difference -0.95; 95% CI -1.64, -0.27; p=0.006) and higher cardiac index (mean difference 0.44; 95% CI 0.17, 0.71; p=0.001). Noradrenaline requirements are similar in both the groups.

CONCLUSION

There is no evidence that levosimendan is superior to dobutamine in adult patients with sepsis and septic shock. Further large randomized trials are necessary in this area.

Sepsis and Immunosenescence in the Elderly Patient: A Review

Sepsis is a prevalent, serious medical condition with substantial mortality and a significant consumption of health-care resources. Its incidence has increased around 9% annually in general population over the last years and specially in aged patients group. Several risk factors such as comorbidities, preadmission status, malnutrition, frailty, and an impared function in the immune system called immunosenescence are involved in the higher predisposition to sepsis in the elderly patients. Immunosenescence status consists in a functional impairment in both cell-mediated immunity and humoral immune responses and increases not only the risk for develop sepsis but also lead to more severe presentation of infection and may be is also related with a higher mortality. There is a also a concern about to admit patients in the intensive care units taking into account that the outcome of elderly patients is poorer compared to younger people. Nevertheless, the management of septic elderly patients does not differ substantially from younger people. In addition, the quality of life in septic elderly survivors is also lower than in younger people. But age, as alone factor, should not be used to determine treatment options because the poorer outcomes is thought to be due to the increased comorbidities and frailty in this group of patients.

Vasopressors During Sepsis: Selection and Targets

Clinicians have greatly improved care for septic shock. Urgent resuscitation using intravenous fluids and vasopressors as well as rapid administration of broad spectrum antibiotics are probably the most basic and universally accepted interventions. Various trials have compared different types of vasopressors, associations of vasopressors and inotropes, and pressure targets. End goal-directed therapy algorithms are designed to optimize oxygen delivery by use of fluids, vasopressors, inotropes, and blood products. Patients who have a poor response to resuscitation and patients with known severe ventricular dysfunction might merit advanced hemodynamic monitoring. This review examines important vasopressor and septic shock trials.

The role of cardiac dysfunction in multiorgan dysfunction

PURPOSE OF REVIEW

The aim of this review was to examine the main determinants of cardiac dysfunction in critically ill patients, as well as how a reduction in cardiac performance influences other organ function.

RECENT FINDINGS

Cardiac dysfunction is a frequent complication in critically ill patients and contributes to organ hypoperfusion and poor outcome. Pathophysiological determinants may include a primary ischaemia/reperfusion injury of the heart, effects of systemic inflammatory and adrenergic responses of the body to a variety of acute insults, as well as cardiovascular effects of commonly applied intensive respiratory or haemodynamic treatments. A strict connection exists between cardiac and other organ function, mediated by haemodynamic, humoral, and immune mechanisms. Heart, lungs, kidneys, and other splanchnic organs such as gut and liver influence each other function in a bidirectional way: this organ crosstalk must be regarded as a key aspect in multiorgan dysfunction.

SUMMARY

The heart should never be regarded as an isolated organ. When dealing with cardiac dysfunction, clinicians must consider the underlying pathophysiology, potential myocardial depressant effects of intensive treatments, and the complex interaction with other organ function.

Hemodynamic coherence in sepsis

Microvascular alterations are a hallmark of sepsis and play a crucial role in its pathophysiology. Such alterations are the result of overwhelming inflammation, which negatively affects all the components of the microcirculation. As the severity of microvascular alterations is associated with organ dysfunction and mortality, several strategies have been tested for improving microcirculation. Nevertheless, they are mainly based on the conventional manipulation of systemic hemodynamics to increase the total flow to the organs and tissues. Other therapeutic interventions are still being investigated. In this review, we discuss the pathophysiology of septic microcirculatory dysfunction and its implications for possible treatments.

Levosimendan for the Prevention of Acute Organ Dysfunction in Sepsis

BACKGROUND

Levosimendan is a calcium-sensitizing drug with inotropic and other properties that may improve outcomes in patients with sepsis.

METHODS

We conducted a double-blind, randomized clinical trial to investigate whether levosimendan reduces the severity of organ dysfunction in adults with sepsis. Patients were randomly assigned to receive a blinded infusion of levosimendan (at a dose of 0.05 to 0.2 μg per kilogram of body weight per minute) for 24 hours or placebo in addition to standard care. The primary outcome was the mean daily Sequential Organ Failure Assessment (SOFA) score in the intensive care unit up to day 28 (scores for each of five systems range from 0 to 4, with higher scores indicating more severe dysfunction; maximum score, 20). Secondary outcomes included 28-day mortality, time to weaning from mechanical ventilation, and adverse events.

RESULTS

The trial recruited 516 patients; 259 were assigned to receive levosimendan and 257 to receive placebo. There was no significant difference in the mean (±SD) SOFA score between the levosimendan group and the placebo group (6.68±3.96 vs. 6.06±3.89; mean difference, 0.61; 95% confidence interval [CI], -0.07 to 1.29; P=0.053). Mortality at 28 days was 34.5% in the levosimendan group and 30.9% in the placebo group (absolute difference, 3.6 percentage points; 95% CI, -4.5 to 11.7; P=0.43). Among patients requiring ventilation at baseline, those in the levosimendan group were less likely than those in the placebo group to be successfully weaned from mechanical ventilation over the period of 28 days (hazard ratio, 0.77; 95% CI, 0.60 to 0.97; P=0.03). More patients in the levosimendan group than in the placebo group had supraventricular tachyarrhythmia (3.1% vs. 0.4%; absolute difference, 2.7 percentage points; 95% CI, 0.1 to 5.3; P=0.04).

CONCLUSIONS

The addition of levosimendan to standard treatment in adults with sepsis was not associated with less severe organ dysfunction or lower mortality. Levosimendan was associated with a lower likelihood of successful weaning from mechanical ventilation and a higher risk of supraventricular tachyarrhythmia. (Funded by the NIHR Efficacy and Mechanism Evaluation Programme and others; LeoPARDS Current Controlled Trials number, ISRCTN12776039 .).

Levosimendan Administration in Limb Ischemia: Multicomponent Signaling Serving Kidney Protection

Aims and Objectives

Acute renal failure is a severe complication of lower extremity major arterial reconstructions, which could even be fatal. Levosimendan is a dual-acting positive inotropic and vasodilatory agent, which is suspected to have protective effects against cardiac ischemia. However, there is no data available on lower limb or remote organ ischemic injuries therefore the aim of the study was to investigate the effect of levosimendan on lower limb ischemia-reperfusion injury and the corollary renal dysfunction.

Methods

Male Wistar rats underwent 180 min bilateral lower limb ischemia followed by 4 or 24 hours of reperfusion. Intravenous Levosimendan was administered continuously (0.2μg/bwkg/min) throughout the whole course of ischemia and the first 3h of reperfusion. Results were compared with sham-operated and ischemia-reperfusion groups. Hemodynamic monitoring was performed by invasive arterial blood pressure measurement. Kidney and lower limb muscle microcirculation was registered by a laser Doppler flowmeter. After 4h and 24h of reperfusion, serum, urine and histological samples were collected.

Results

Systemic hemodynamic parameters and microcirculation of kidney and the lower limb significantly improved in the Levosimendan treated group. Muscle viability was significantly preserved 4 and 24 hours after reperfusion. At the same time, renal functional laboratory tests and kidney histology demonstrated significantly less expressive kidney injury in Levosimendan groups. TNF-α levels were significantly less elevated in the Levosimendan group 4 hours after reperfusion.

Conclusion

The results claim a protective role for Levosimendan administration during major vascular surgeries to prevent renal complications.

Association of Microcirculation, Macrocirculation, and Severity of Illness in Septic Shock: A Prospective Observational Study to Identify Microcirculatory Targets Potentially Suitable for Guidance of Hemodynamic Therapy

PURPOSE

Clinically unapparent microcirculatory impairment is common and has a negative impact on septic shock, but specific therapy is not established so far. This prospective observational study aimed at identifying candidate parameters for microcirculatory-guided hemodynamic therapy. ClinicalTrials.gov : NCT01530932.

MATERIALS AND METHODS

Microcirculatory flow and postcapillary venous oxygen saturation were detected during vaso-occlusive testing (VOT) on days 1 (T0), 2 (T24), and 4 (T72) in 20 patients with septic shock at a surgical intensive care unit using a laser Doppler spectrophotometry system (O2C).

RESULTS

Reperfusional maximal venous capillary oxygen saturation (SvcO₂max) showed negative correlations with Simplified Acute Physiology Score II (SAPSII)/Sequential Organ Failure Assessment (SOFA) score, norepinephrine dosage, and lactate concentration and showed positive correlations with cardiac index (CI). At T24 and T72, SvcO₂max was also inversely linked to fluid balance. With respect to any predictive value, SvcO₂max and CI determined on day 1 (T0) were negatively correlated with SAPS II/SOFA on day 4 (T72). Moreover, SvcO₂max measured on day 1 or day 2 was negatively correlated with cumulated fluid balance on day 4 ( r= -.472, P < .05 and r = -.829, P < .001). By contrast, CI neither on day 1 nor on day 2 was correlated with cumulated fluid balance on day 4 ( r = -.343, P = .17 and r = -.365, P = .15).

CONCLUSION

In patients with septic shock, microcirculatory reserve as assessed by SvcO₂max following VOT was impaired and negatively correlated with severity of illness and fluid balance. In contrast to CI, SvcO₂max determined on day 1 or day 2 was significantly negatively correlated with cumulative fluid balance on day 4. Therefore, early microcirculatory measurement of SvcO₂max might be superior to CI in guidance of sepsis therapy to avoid fluid overload. This has to be addressed in future clinical studies.

Vasoactive agents for the treatment of sepsis

The article describes some commonly used vasoactive agents in patients with septic shock. Depending on their distinct pharmacological properties, their effects on vascular bed and cardiac function are different. For example, dopamine has equivalent effect on heart and vasculature, which can result in increases in cardiac output, mean arterial pressure and heart rate. Dobutamine is considered as inodilator because it has potent effect on cardiac systole and vasculature. Patients with sepsis and septic shock sometimes have coexisting cardiac dysfunction that justifies the use of dobutamine. Levosimendan is a relatively new agent exerting its inodilator effect by increasing sensitivity of myocardium to calcium. Some preliminary studies showed a promising result of levosimendan on reducing mortality.

Impact of microcirculatory video quality on the evaluation of sublingual microcirculation in critically ill patients

We aimed to assess the impact of image quality on microcirculatory evaluation with sidestream dark-field (SDF) videomicroscopy in critically ill patients and explore factors associated with low video quality. This was a retrospective analysis of a single-centre prospective observational study. Videos of the sublingual microcirculation were recorded using SDF videomicroscopy in 100 adult patients within 12 h from admittance to the intensive care unit and every 24 h until discharge/death. Parameters of vessel density and perfusion were calculated offline for small vessels. For all videos, a quality score (-12 = unacceptable, 1 = suboptimal, 2 = optimal) was assigned for brightness, focus, content, stability, pressure and duration. Videos with a total score ≤8 were deemed as unacceptable. A total of 2455 videos (853 triplets) was analysed. Quality was acceptable in 56 % of videos. Lower quality was associated with worse microvascular density and perfusion. Unreliable triplets (≥1 unacceptable or missing video, 65 % of total) showed lower vessel density, worse perfusion and higher flow heterogeneity as compared to reliable triplets (p < 0.001). Quality was higher among triplets collected by an extensively-experienced investigator or in patients receiving sedation or mechanical ventilation. Perfused vessel density was higher in patients with Glasgow Coma Scale (GCS) ≤8 (18.9 ± 4.5 vs. 17.0 ± 3.9 mm/mm² in those with GCS >8, p < 0.001) or requiring mechanical ventilation (18.0 ± 4.5 vs. 17.2 ± 3.8 mm/mm² in not mechanically ventilated patients, p = 0.059). We concluded that SDF video quality depends on both the operator's experience and patient's cooperation. Low-quality videos may produce spurious data, leading to an overestimation of microvascular alterations.

Levosimendan beyond inotropy and acute heart failure: Evidence of pleiotropic effects on the heart and other organs: An expert panel position paper

Levosimendan is a positive inotrope with vasodilating properties (inodilator) indicated for decompensated heart failure (HF) patients with low cardiac output. Accumulated evidence supports several pleiotropic effects of levosimendan beyond inotropy, the heart and decompensated HF. Those effects are not readily explained by cardiac function enhancement and seem to be related to additional properties of the drug such as anti-inflammatory, anti-oxidative and anti-apoptotic ones. Mechanistic and proof-of-concept studies are still required to clarify the underlying mechanisms involved, while properly designed clinical trials are warranted to translate preclinical or early-phase clinical data into more robust clinical evidence. The present position paper, derived by a panel of 35 experts in the field of cardiology, cardiac anesthesiology, intensive care medicine, cardiac physiology, and cardiovascular pharmacology from 22 European countries, compiles the existing evidence on the pleiotropic effects of levosimendan, identifies potential novel areas of clinical application and defines the corresponding gaps in evidence and the required research efforts to address those gaps.

Microcirculatory dysfunction in sepsis: pathophysiology, clinical monitoring, and potential therapies

Abnormal microvascular perfusion, including decreased functional capillary density and increased blood flow heterogeneity, is observed in early stages of the systemic inflammatory response to infection and appears to have prognostic significance in human sepsis. It is known that improvements in systemic hemodynamics are weakly correlated with the correction of microcirculatory parameters, despite an appropriate treatment of macrohemodynamic abnormalities. Furthermore, conventional hemodynamic monitoring systems available in clinical practice fail to detect microcirculatory parameter changes and responses to treatments, as they do not evaluate intrinsic events that occur in the microcirculation. Fortunately, some bedside diagnostic methods and therapeutic options are specifically directed to the assessment and treatment of microcirculatory changes. In the present review we discuss fundamental aspects of septic microcirculatory abnormalities, including pathophysiology, clinical monitoring, and potential therapies.

Levosimendan Versus Dobutamine in Myocardial Injury Patients with Septic Shock: A Randomized Controlled Trial

BACKGROUND We aimed to investigate the effect of levosimendan on biomarkers of myocardial injury and systemic hemodynamics in patients with septic shock. MATERIAL AND METHODS After achieving normovolemia and a mean arterial pressure of at least 65 mmHg, 38 septic shock patients with low cardiac output (left ventricular ejective fraction), LEVF £45%) were randomly divided into two groups: levosimendan dobutamine. Patients in the levosimendan and dobutamine groups were maintained with intravenous infusion of levosimendan (0.2 μg/kg/minute) and dobutamine (5 μg/kg/minute) for 24 hours respectively. During treatment we monitored hemodynamics and LVEF, and measured levels of heart-type fatty acid binding protein (HFABP), troponin I (TNI), and brain natriuretic peptide(BNP). In addition, the length of mechanical ventilation, intensive care unit (ICU) stay, hospital stay, and 28-day mortality were compared between the two groups. RESULTS The levosimendan group and the dobutamine group were well matched with respect to age (years, 55.4 ± 1 7.5 versus 50.2 ± 13.6) and gender (males, 68.4% versus 57.9%). Levosimendan-treated patients had higher stroke volume index (SVI), cardiac index (CI), LVEF, and left ventricular stroke work index (LVSWI), and lower extravascular lung water index (EVLWI) compared to dobutamine-treated patients (p<0.05). HFABP, TNI, and BNP in the levosimendan group were less than in the dobutamine group (p<0.05). There was no difference in the mechanical ventilation time, length of stay in ICU and hospital, and 28-day mortality between the two groups. CONCLUSIONS Compared with dobutamine, levosimendan reduces biomarkers of myocardial injury and improves systemic hemodynamics in patients with septic shock. However, it does not reduce the days on mechanical ventilation, length of stay in ICU and hospital, or 28-day mortality.

Sepsis: in search of cure

INTRODUCTION

Sepsis is a complex inflammatory disorder believed to originate from an infection by any types of microbes and/or their products. It is the leading cause of death in intensive care units (ICUs) throughout the globe. The mortality rates depend both on the severity of infection and the host's response to infection.

METHODS

Literature survey on pathobiology of sepsis in general and failure of more than hundred clinical trials conducted so far in search of a possible cure for sepsis resulted in the preparation of this manuscript.

FINDINGS

Sepsis lacks a suitable animal model that mimics human sepsis. However, based on the results obtained in animal models of sepsis, clinical trials conducted so far have been disappointing. Although involvement of multiple mediators and pathways in sepsis has been recognized, only few components are being targeted and this could be the major reason behind the failure of clinical trials.

CONCLUSION

Inability to recognize a single critical mediator of sepsis may be the underlying cause for the poor therapeutic intervention of sepsis. Therefore, sepsis is still considered as a disease-in search of cure.

Microcirculatory alterations during haemorrhagic shock and after resuscitation in a paediatric animal model

BACKGROUND

Haemorrhagic shock is frequent in paediatric trauma patients and after cardiac surgery, especially after cardiopulmonary bypass. It has demonstrated to be related to bad outcome.

OBJECTIVES

To evaluate changes on microcirculatory parameters during haemorrhagic shock and resuscitation in a paediatric animal model. To determine correlation between microcirculatory parameters and other variables routinely used in the monitoring of haemorrhagic shock.

METHODS

Experimental study on 17 Maryland pigs. Thirty minutes after haemorrhagic shock induction by controlled bleed animals were randomly assigned to three treatment groups receiving 0.9% normal saline, 5% albumin with 3% hypertonic saline, or 5% albumin with 3% hypertonic saline plus a bolus of terlipressin. Changes on microcirculation (perfused vessel density (PVD), microvascular blood flow (MFI) and heterogeneity index (HI)) were evaluated and compared with changes on macrocirculation and tisular perfusion parameters.

RESULTS

Shock altered microcirculation: PVD decreased from 13.5 to 12.3 mm mm(-2) (p=0.05), MFI decreased from 2.7 to 1.9 (p<0.001) and HI increased from 0.2 to 0.5 (p<0.001). After treatment, microcirculatory parameters returned to baseline (PVD 13.6 mm mm(-2) (p<0.05), MFI 2.6 (p<0.001) and HI 0.3 (p<0.05)). Microcirculatory parameters showed moderate correlation with other parameters of tissue perfusion. There were no differences between treatments.

CONCLUSIONS

Haemorrhagic shock causes important microcirculatory alterations, which are reversed after treatment. Microcirculation should be assessed during haemorrhagic shock providing additional information to guide resuscitation.

Early prevention of trauma-related infection/sepsis

Trauma still represents one of the major causes of death worldwide. Despite the reduction of post-traumatic sepsis over the past two decades, the mortality of septic trauma inpatients is still high (19.5-23 %). Early prevention of sepsis development can aid in the subsequent treatment of patients and help improve their outcomes. To date, the prevention of trauma-related infection/sepsis has mainly included infection prevention (e.g., surgical management, prophylactic antibiotics, tetanus vaccination, immunomodulatory interventions) and organ dysfunction prevention (e.g., pharmaceuticals, temporary intravascular shunts, lung-protective strategies, enteral immunonutrition, acupuncture). Overall, more efficient ways should be developed to prevent trauma-related infection/sepsis.

To beta block or not to beta block; that is the question

The fast-acting β-1 blocker esmolol has been the center of attention since the landmark article by Morrelli and colleagues suggesting that, in patients with sepsis, reducing heart rate by administering esmolol can result in a survival benefit. However, the use of esmolol for the treatment of sepsis and the underlying mechanism responsible for this benefit remain controversial. This commentary discusses the study by Jacquet-Lagrèze and colleagues, who in a pig model of sepsis tested the hypothesis that administration of esmolol to reduce heart rate may correct sepsis-induced sublingual and gut microcirculatory alterations which are known to be associated with adverse outcome.

Effects of ketanserin on microcirculatory alterations in septic shock: An open-label pilot study

INTRODUCTION

Microcirculatory alterations in sepsis are associated with increased morbidity and mortality. These alterations occur despite macrohemodynamic resuscitation. Alternative pro-microcirculatory strategies, including vasodilatory drugs, have been suggested to improve capillary blood flow. Ketanserin, a serotonin receptor antagonist, is an attractive candidate because of its vasodilatory, antithrombotic, and anti-inflammatory effects.

METHODS

This is an open-label pilot study on the effect of ketanserin administration on microcirculatory alterations in septic shock, defined as microvascular flow index (MFI)≤2.5 after a strict macrohemodynamic resuscitation protocol. Sidestream dark-field imaging was applied to assess the microcirculation. A stepwise incremental dose regiment was applied until an MFI>2.9, the primary end point, was reached.

RESULTS

Ten patients (Acute Physiology and Chronic Health Evaluation IV scores of 115 [100-136]) were included. Baseline MFI was 1.71 (1.31-2.32) and was significantly increasing to 2.96 (2.54-3.00; P=.021) during the ketanserin infusion. The total ketanserin dose was 0.09 (0.08-0.13) mg/kg per patient in 60 (30-60) minutes. In 3 patients (30%), the ketanserin infusion was discontinued due to refractory hypotension.

CONCLUSION

An improvement in microcirculatory perfusion was observed during ketanserin administration in patients with septic shock after macrohemodynamic resuscitation. This finding needs further exploration in a placebo-controlled setting.

Levosimendan reduces mortality in patients with severe sepsis and septic shock: A meta-analysis of randomized trials

PURPOSE

There is controversy about the use of inotropes in the treatment of severe sepsis and septic shock. The objective of this study was to evaluate if levosimendan, as compared with standard inotropic therapy (eg, dobutamine), reduces mortality in septic patients.

MATERIALS AND METHODS

BioMedCentral, PubMed, EMBASE, and the Cochrane Central Register were searched for pertinent studies, up to 1st May 2015. Randomized trials on the use of levosimendan in patients with severe sepsis and septic shock were included if reporting mortality data. The primary outcome was mortality, whereas secondary outcomes were blood lactate, cardiac index, total fluid infused, norepinephrine dosage, and mean arterial pressure.

RESULTS

Seven studies for a total of 246 patients were included in the analysis. Levosimendan was associated with significantly reduced mortality compared with standard inotropic therapy (59/125 [47%] in the levosimendan group and 74/121 [61%] in the control group; risk difference = -0.14, risk ratio = 0.79 [0.63-0.98], P for effect = .03, I(2) = 0%, numbers needed to treat = 7). Blood lactate was significantly reduced in the levosimendan group, whereas cardiac index and total fluid infused were significantly higher in the levosimendan group. No difference in mean arterial pressure and norepinephrine usage was noted.

CONCLUSIONS

In patients with severe sepsis and septic shock, levosimendan is associated with a significant reduction in mortality compared with standard inotropic therapy. A large ongoing multicenter randomized trial will have to confirm these findings.

International study on microcirculatory shock occurrence in acutely ill patients

OBJECTIVES

Microcirculatory alterations are associated with adverse outcome in subsets of critically ill patients. The prevalence and significance of microcirculatory alterations in the general ICU population are unknown. We studied the prevalence of microcirculatory alterations in a heterogeneous ICU population and its predictive value in an integrative model of macro- and microcirculatory variables.

DESIGN

Multicenter observational point prevalence study.

SETTING

The Microcirculatory Shock Occurrence in Acutely ill Patients study was conducted in 36 ICUs worldwide.

PATIENTS

A heterogeneous ICU population consisting of 501 patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Demographic, hemodynamic, and laboratory data were collected in all ICU patients who were 18 years old or older. Sublingual Sidestream Dark Field imaging was performed to determine the prevalence of an abnormal capillary microvascular flow index (< 2.6) and its additional value in predicting hospital mortality. In 501 patients with a median Acute Physiology and Chronic Health Evaluation II score of 15 (10-21), a Sequential Organ Failure Assessment score of 5 (2-8), and a hospital mortality of 28.4%, 17% exhibited an abnormal capillary microvascular flow index. Tachycardia (heart rate > 90 beats/min) (odds ratio, 2.71; 95% CI, 1.67-4.39; p < 0.001), mean arterial pressure (odds ratio, 0.979; 95% CI, 0.963-0.996; p = 0.013), vasopressor use (odds ratio, 1.84; 95% CI, 1.11-3.07; p = 0.019), and lactate level more than 1.5 mEq/L (odds ratio, 2.15; 95% CI, 1.28-3.62; p = 0.004) were independent risk factors for hospital mortality, but not abnormal microvascular flow index. In reference to microvascular flow index, a significant interaction was observed with tachycardia. In patients with tachycardia, the presence of an abnormal microvascular flow index was an independent, additive predictor for in-hospital mortality (odds ratio, 3.24; 95% CI, 1.30-8.06; p = 0.011). This was not true for nontachycardic patients nor for the total group of patients.

CONCLUSIONS

In a heterogeneous ICU population, an abnormal microvascular flow index was present in 17% of patients. This was not associated with mortality. However, in patients with tachycardia, an abnormal microvascular flow index was independently associated with an increased risk of hospital death.

Levosimendan Improves Neurological Outcome in a Swine Model of Asphyxial Cardiac Arrest

BACKGROUND

In asphyxial cardiac arrest, the severe hypoxic stress complicates the resuscitation efforts and results in poor neurological outcomes. Our aim was to assess the effects of levosimendan on a swine model of asphyxial cardiac arrest.

METHODS

Asphyxial cardiac arrest was induced in 20 Landrace/Large White piglets, which were subsequently left untreated for four minutes. The animals were randomised to receive adrenaline alone (n=10, Group A) and adrenaline plus levosimendan (n=10, Group B). All animals were resuscitated according to the 2010 European Resuscitation Council guidelines. Haemodynamic variables were measured before arrest, during arrest and resuscitation, and during the first 30 minutes after return of spontaneous circulation (ROSC), while survival and neurologic alertness score were measured 24 hours later.

RESULTS

Return of spontaneous circulation was achieved in six animals (60%) from Group A and nine animals (90%) from Group B (p=0.303). During the first minute of cardiopulmonary resuscitation, coronary perfusion pressure was significantly higher in Group B (p=0.046), but there was no significant difference at subsequent time points until ROSC. Although six animals (60%) from each group survived after 24 hours (p=1.000), neurologic examination was significantly better in the animals of Group B (p<0.01).

CONCLUSIONS

The addition of levosimendan to adrenaline improved coronary perfusion pressure immediately after the onset of cardiopulmonary resuscitation and resulted in better 24-hour neurological outcome.

Randomized controlled trial of inhaled nitric oxide for the treatment of microcirculatory dysfunction in patients with sepsis*

OBJECTIVES

Sepsis treatment guidelines recommend macrocirculatory hemodynamic optimization; however, microcirculatory dysfunction is integral to sepsis pathogenesis. We aimed to test the hypothesis that following macrocirculatory optimization, inhaled nitric oxide would improve microcirculation in patients with sepsis and that improved microcirculation would improve lactate clearance and multiple organ dysfunction.

DESIGN

Randomized, sham-controlled clinical trial.

SETTING

Single urban academic medical center.

PATIENTS

Adult patients with severe sepsis and systolic blood pressure less than 90 mm Hg despite intravascular volume expansion and/or serum lactate greater than or equal to 4.0 mmol/L.

INTERVENTIONS

After achievement of macrocirculatory resuscitation goals, we randomized patients to 6 hours of inhaled nitric oxide (40 ppm) or sham inhaled nitric oxide administration. We administered study drug via a specialized delivery device that concealed treatment allocation so that investigators and clinical staff remained blinded.

MEASUREMENTS AND MAIN RESULTS

We performed sidestream dark-field videomicroscopy of the sublingual microcirculation prior to and 2 hours after study drug initiation. The primary outcome measure was the change in microcirculatory flow index. Secondary outcomes were lactate clearance and change in Sequential Organ Failure Assessment score. We enrolled 50 patients (28 of 50 [56%] requiring vasopressor agents; 15 of 50 [30%] died). Although inhaled nitric oxide significantly raised plasma nitrite levels, it did not improve microcirculatory flow, lactate clearance, or organ dysfunction. In contrast to previous studies conducted during the earliest phase of resuscitation, we found no association between changes in microcirculatory flow and lactate clearance or organ dysfunction.

CONCLUSIONS

Following macrocirculatory optimization, inhaled nitric oxide at 40 ppm did not augment microcirculatory perfusion in patients with sepsis. Further, we found no association between microcirculatory perfusion and multiple organ dysfunction after initial resuscitation.

Beneficial impact of levosimendan in critically ill patients with or at risk for acute renal failure: a meta-analysis of randomized clinical trials

INTRODUCTION

The incidence of Acute Kidney Injury is nowadays high in critically ill patients. Its etiology is multifactorial and a primary role is played by low cardiac output syndrome. Everything targeted to normalize cardiac output should increase the renal perfusion and abolish the secondary vasoconstriction. Levosimendan is a calcium sensitizer drug with inotropic properties that improves cardiac output and seems to increase renal blood flow. The aim of this meta-analysis was to evaluate the role of levosimendan in critically ill patients with or at risk of Acute Kidney Injury.

METHODS

We performed a meta-analysis of  randomized controlled trials searching for trials that compared levosimendan with any comparator. The endpoints were the number of patients receiving Renal Replacement Therapy after randomization and the number of patients developing Acute Kidney Injury.

RESULTS

Final analysis included 33 trials and 3,879 patients (2,024 levosimendan and 1,855 control). The overall analysis showed that the use of levosimendan was associated with a significant reduction in the risk of Renal Replacement Therapy (17 of 492 [3.5%] in the levosimendan group versus 37 of 427 [8.7%] in the control group, relative risk =0.52 [0.32 to 0.86], p for effect =0.01) and of Acute Kidney Injury (114 of 1,598 [7.1%] in the levosimendan group versus 143 of 1,529 [9.4%] in the control arm, relative risk =0.79 [0.63 to 0.99], p for effect =0.048).

CONCLUSIONS

This meta-analysis suggests that the use of levosimendan is associated with a significant reduction of Renal Replacement Therapy in critically ill patients.

Levosimendan attenuates multiple organ injury and improves survival in peritonitis-induced septic shock: studies in a rat model

INTRODUCTION

The aim of this study was to investigate the effects of levosimendan on rodent septic shock induced by cecal ligation and puncture (CLP).

METHODS

Three hours after peritonitis-induced sepsis, male Wistar rats were randomly assigned to receive an intravenous infusion of levosimendan (1.2 μg/kg/min for 10 min and then 0.3 μg/kg/min for 6 h) or an equivalent volume of saline and vehicle (5% dextrose) solution.

RESULTS

The levosimendan-treated CLP animals had significantly higher arterial pressure and lower biochemical indices of liver and kidney dysfunction compared to the CLP animals (P < 0.05). Plasma interleukin-1β, nitric oxide and organ superoxide levels in the levosimendan-treated CLP group were less than those in CLP rats treated with vehicle (P < 0.05). In addition, the inducible nitric oxide synthase (iNOS) in lung and caspase-3 expressions in spleen were significantly lower in the levosimendan-treated CLP group (P < 0.05). The administration of CLP rats with levosimendan was associated with significantly higher survival (61.9% vs. 40% at 18 h after CLP, P < 0.05). At postmortem examination, the histological changes and neutrophil filtration index in liver and lung were significantly attenuated in the levosimendan-treated CLP group (vs. CLP group, P < 0.05).

CONCLUSIONS

In this clinically relevant model of septic shock induced by fecal peritonitis, the administration of levosimendan had beneficial effects on haemodynamic variables, liver and kidney dysfunction, and metabolic acidosis. (1) Lower levels of interleukin-1β, nitric oxide and superoxide, (2) attenuation of iNOS and caspase-3 expressions, and (3) decreases of neutrophil infiltration by levosimendan in peritonitis-induced sepsis animals suggest that anti-inflammation and anti-apoptosis effects of levosimendan contribute to prolonged survival.

The Japanese guidelines for the management of sepsis

This is a guideline for the management of sepsis, developed by the Sepsis Registry Committee of The Japanese Society of Intensive Care Medicine (JSICM) launched in March 2007. This guideline was developed on the basis of evidence-based medicine and focuses on unique treatments in Japan that have not been included in the Surviving Sepsis Campaign guidelines (SSCG), as well as treatments that are viewed differently in Japan and in Western countries. Although the methods in this guideline conform to the 2008 SSCG, the Japanese literature and the results of the Sepsis Registry Survey, which was performed twice by the Sepsis Registry Committee in intensive care units (ICUs) registered with JSICM, are also referred. This is the first and original guideline for sepsis in Japan and is expected to be properly used in daily clinical practice.

This article is translated from Japanese, originally published as “The Japanese Guidelines for the Management of Sepsis” in the Journal of the Japanese Society of Intensive Care Medicine (J Jpn Soc Intensive Care Med), 2013; 20:124–73. The original work is at http://dx.doi.org/10.3918/jsicm.20.124.

Monitoring the microcirculation in critically ill patients

Alterations in microvascular perfusion have been identified in critically ill patients, especially in sepsis but also in cardiogenic shock, after cardiac arrest, and in high-risk surgery patients. These alterations seem to be implicated in the development of organ dysfunction and are associated with outcome. Even though microvascular perfusion can sometimes be homogenously decreased as in acute hemorrhage or in non-resuscitated cardiogenic shock, heterogeneity of perfusion is observed in sepsis and in resuscitated hemorrhagic/cardiogenic shock. Heterogeneity of perfusion has major implications for monitoring, as many techniques cannot detect microcirculatory alterations when heterogeneity of flow is present in significant amount. Indeed, devices such as laser Doppler or O2 electrodes and near-infrared spectroscopy have a relatively large sampling volume and measurements are affected by the highest values in the field. Using these techniques during a vascular occlusion test may help to characterize microvascular reactivity; however, microvascular reactivity sometimes fails to represent actual microvascular perfusion. Videomicroscopic techniques can nowadays be applied at bedside but are still restricted to some selected patients (quiet or sedated patients). Tissue PCO2 is an elegant alternative but is not yet broadly used. In this manuscript, we discuss the main advantages and limitations of the techniques available for bedside evaluation of the microcirculation in critically ill patients.

The effect of levosimendan on lung damage after myocardial ischemia reperfusion in rats in which experimental diabetes was induced

BACKGROUND

It is known that diabetic complications and lipid peroxidation are closely associated. During ischemia and reperfusion (IR), injury may occur in distant organs, as well as in tissues next to the region exposed to the ischemia, and the lungs can be one of the most affected of these organs. Therefore, this study investigated the effects of levosimendan on lung tissue and the oxidant-antioxidant system in diabetic rats.

MATERIALS AND METHODS

The study was conducted in 24 Wistar albino rats that were separated into four groups (C, control; DC, diabetic control; DIR, diabetic IR; and DIRL, diabetic IR levosimendan). Diabetes was induced in 18 rats using streptozotocin (55 mg/kg), and the animals were randomly separated into three groups after the effects of the diabetes became apparent. After a left thoracotomy, ischemia was performed on the myocardial muscle with the left main coronary artery (LAD) for 30 min in the DIR and DIRL groups. After ischemia, the LAD ligation was removed, and reperfusion was applied for 120 min. Single-dose intraperitoneal 12 μg/kg levosimendan was administered to group DIRL before the ischemia. Group DC was evaluated as the diabetic control group, and six rats were considered to be the control group (group C), in which thoracotomy was performed and then closed with no induction of myocardial ischemia. We measured the levels of malondialdehyde, as a lipid peroxidation end product, as well as catalase and glutathione S-transferase activities, as antioxidant enzymes in the lung tissue. Tissue samples were also examined histopathologically.

RESULTS

Neutrophil infiltration or aggregation in lung tissue was significantly higher in the DIR group compared with the C, DC, and DIRL groups (P = 0.003, P = 0.026, and P = 0.026, respectively). Alveolar wall thickening in lung tissue was significantly higher in the DIR group compared with the C, DC, and DIRL groups (P = 0.002, P = 0.002, and P = 0.006, respectively). In addition, the lung tissue damage score was significantly higher in the DIR group compared with the C, DC, and DIRL groups (P = 0.001, P = 0.004, and P = 0.007, respectively). Finally, catalase and glutathione S-transferase activity levels were significantly higher in the DIR group compared with those observed in the C, DC, and DIRL groups.

CONCLUSIONS

Although diabetes increases lipid peroxidation, it suppresses antioxidant activity. Our results showed that levosimendan had a protective effect against lung damage secondary to IR in the rats with induced diabetes. We recommend that experimental and clinical studies be conducted to examine the effects of levosimendan at different doses and different IR durations on various organs for clinical use.

Clinical assessment of peripheral perfusion to predict postoperative complications after major abdominal surgery early: a prospective observational study in adults

INTRODUCTION

Altered peripheral perfusion is strongly associated with poor outcome in critically ill patients. We wanted to determine whether repeated assessments of peripheral perfusion during the days following surgery could help to early identify patients that are more likely to develop postoperative complications.

METHODS

Haemodynamic measurements and peripheral perfusion parameters were collected one day prior to surgery, directly after surgery (D0) and on the first (D1), second (D2) and third (D3) postoperative days. Peripheral perfusion assessment consisted of capillary refill time (CRT), peripheral perfusion index (PPI) and forearm-to-fingertip skin temperature gradient (T(skin-diff)). Generalized linear mixed models were used to predict severe complications within ten days after surgery based on Clavien-Dindo classification.

RESULTS

We prospectively followed 137 consecutive patients, from among whom 111 were included in the analysis. Severe complications were observed in 19 patients (17.0%). Postoperatively, peripheral perfusion parameters were significantly altered in patients who subsequently developed severe complications compared to those who did not, and these parameters persisted over time. CRT was altered at D0, and PPI and T(skin-diff) were altered on D1 and D2, respectively. Among the different peripheral perfusion parameters, the diagnostic accuracy in predicting severe postoperative complications was highest for CRT on D2 (area under the receiver operating characteristic curve = 0.91 (95% confidence interval (CI) = 0.83 to 0.92)) with a sensitivity of 0.79 (95% CI = 0.54 to 0.94) and a specificity of 0.93 (95% CI = 0.86 to 0.97). Generalized mixed-model analysis demonstrated that abnormal peripheral perfusion on D2 and D3 was an independent predictor of severe postoperative complications (D2 odds ratio (OR) = 8.4, 95% CI = 2.7 to 25.9; D2 OR = 6.4, 95% CI = 2.1 to 19.6).

CONCLUSIONS

In a group of patients assessed following major abdominal surgery, peripheral perfusion alterations were associated with the development of severe complications independently of systemic haemodynamics. Further research is needed to confirm these findings and to explore in more detail the effects of peripheral perfusion-targeted resuscitation following major abdominal surgery.

An efficacy and mechanism evaluation study of Levosimendan for the Prevention of Acute oRgan Dysfunction in Sepsis (LeoPARDS): protocol for a randomized controlled trial

BACKGROUND

Organ dysfunction consequent to infection ('severe sepsis') is the leading cause of admission to an intensive care unit (ICU). In both animal models and early clinical studies the calcium channel sensitizer levosimendan has been demonstrated to have potentially beneficial effects on organ function. The aims of the Levosimendan for the Prevention of Acute oRgan Dysfunction in Sepsis (LeoPARDS) trial are to identify whether a 24-hour infusion of levosimendan will improve organ dysfunction in adults who have septic shock and to establish the safety profile of levosimendan in this group of patients.

METHODS/DESIGN

This is a multicenter, randomized, double-blind, parallel group, placebo-controlled trial. Adults fulfilling the criteria for systemic inflammatory response syndrome due to infection, and requiring vasopressor therapy, will be eligible for inclusion in the trial. Within 24 hours of meeting these inclusion criteria, patients will be randomized in a 1:1 ratio stratified by the ICU to receive either levosimendan (0.05 to 0.2 μg.kg⁻¹.min⁻¹ or placebo for 24 hours in addition to standard care. The primary outcome measure is the mean Sequential Organ Failure Assessment (SOFA) score while in the ICU. Secondary outcomes include: central venous oxygen saturations and cardiac output; incidence and severity of renal failure using the Acute Kidney Injury Network criteria; duration of renal replacement therapy; serum bilirubin; time to liberation from mechanical ventilation; 28-day, hospital, 3 and 6 month survival; ICU and hospital length-of-stay; and days free from catecholamine therapy. Blood and urine samples will be collected on the day of inclusion, at 24 hours, and on days 4 and 6 post-inclusion for investigation of the mechanisms by which levosimendan might improve organ function. Eighty patients will have additional blood samples taken to measure levels of levosimendan and its active metabolites OR-1896 and OR-1855. A total of 516 patients will be recruited from approximately 25 ICUs in the United Kingdom.

DISCUSSION

This trial will test the efficacy of levosimendan to reduce acute organ dysfunction in adult patients who have septic shock and evaluate its biological mechanisms of action.

TRIAL REGISTRATION

Current controlled trials ISRCTN12776039 (19 September 2013).

Levosimendan in critical illness: a literature review

Levosimendan, the active enantiomer of simendan, is a calcium sensitizer developed for treatment of decompensated heart failure, exerts its effects independently of the beta adrenergic receptor and seems beneficial in cases of severe, intractable heart failure. Levosimendan is usually administered as 24-h infusion, with or without a loading dose, but dosing needs adjustment in patients with severe liver or renal dysfunction. Despite several promising reports, the role of levosimendan in critical illness has not been thoroughly evaluated. Available evidence suggests that levosimendan is a safe treatment option in critically ill patients and may reduce mortality from cardiac failure. However, data from well-designed randomized controlled trials in critically ill patients are needed to validate or refute these preliminary conclusions. This literature review is an attempt to synthesize available evidence on the role and possible benefits of levosimendan in critically ill patients with severe heart failure.

Inotropic agents and vasodilator strategies for acute myocardial infarction complicated by cardiogenic shock or low cardiac output syndrome

BACKGROUND

The recently published German-Austrian S3 Guideline for the treatment of infarct related cardiogenic shock (CS) revealed a lack of evidence for all recommended therapeutic measures.

OBJECTIVES

To determine the effects in terms of efficacy, efficiency and safety of cardiac care with inotropic agents and vasodilator strategies versus placebo or against each other for haemodynamic stabilisation following surgical treatment, interventional therapy (angioplasty, stent implantation) and conservative treatment (that is no revascularization) on mortality and morbidity in patients with acute myocardial infarction (AMI) complicated by CS or low cardiac output syndrome (LCOS).

SEARCH METHODS

We searched CENTRAL, MEDLINE (Ovid), EMBASE (Ovid) and ISI Web of Science, registers of ongoing trials and proceedings of conferences in January 2013. Reference lists were scanned and experts in the field were contacted to obtain further information. No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials in patients with AMI complicated by CS or LCOS.

DATA COLLECTION AND ANALYSIS

Data collection and analysis were performed according to the published protocol. All trials were analysed individually. Hazard ratios (HRs) and odds ratios with 95% confidence intervals (CI) were extracted but not pooled because of high heterogeneity between the control group interventions.

MAIN RESULTS

Four eligible, very small studies were identified from a total of 4065 references. Three trials with high overall risk of bias compared levosimendan to standard treatment (enoximone or dobutamine) or placebo. Data from a total of 63 participants were included in our comparisons, 31 were treated with levosimendan and 32 served as controls. Levosimendan showed an imprecise survival benefit in comparison with enoximone based on a very small trial with 32 participants (HR 0.33; 95% CI 0.11 to 0.97). Results from the other similarly small trials were too imprecise to provide any meaningful information about the effect of levosimendan in comparison with dobutamine or placebo. Only small differences in haemodynamics, length of hospital stay and the frequency of major adverse cardiac events or adverse events overall were found between study groups.Only one small randomised controlled trial with three participants was found for vasodilator strategies (nitric oxide gas versus placebo) in AMI complicated by CS or LCOS. This study was too small to draw any conclusions on the effects on our key outcomes.

AUTHORS' CONCLUSIONS

At present there are no robust and convincing data to support a distinct inotropic or vasodilator drug based therapy as a superior solution to reduce mortality in haemodynamically unstable patients with CS or low cardiac output complicating AMI.

Isoproterenol infusion and microcirculation in septic shock

INTRODUCTION

Our study primarily aimed at investigating the effect of isoproterenol infusion on tissue oxygen saturation in patients with septic shock. The secondary aim was to assess the relation between cardiac index, central venous oxygen saturation and tissue oxygen saturation.

METHODS

This retrospective study was conducted from December 2010 to March 2012. We included 14 consecutive patients with septic shock treated with isoproterenol. All patients were monitored by cardiac index and tissue oxygen saturation. From medical charts, routine hemodynamic data were extracted one hour before and six hours after the onset of isoproterenol infusion.

RESULTS

From baseline to H6, tissue oxygen saturation levels rise from 78 [72-82]% to 85 [78-88]% (p = 0.03). Isoproterenol infusion was associated with an increase of central venous oxygen saturation (from 67 [65-74]% to 84 [77-86]%, p = 0.02) and cardiac index (from 2.9 [2.7-3.1] L/min/m² to 3.9 [3.0-4.4] L/min/m², p = 0.006). Tissue oxygen saturation was correlated neither to cardiac index (p = 0.14, R(2) = 0.08) nor to central venous oxygen saturation (p = 0.19, R(2) = 0.10).

CONCLUSIONS

Use of isoproterenol was associated with an increase of tissue oxygen saturation. This increase was not correlated to cardiac index, suggesting a decoupling between macrocirculation and microcirculation.

Inotropic Support in the Treatment of Septic Myocardial Dysfunction: Pathophysiological Implications Supporting the Use of Levosimendan

Myocardial dysfunction is a frequent organ manifestation during septic shock and the subsequent impairment in cardiac output may result in organ hypoperfusion, requiring prompt and adequate treatment to restore cardiovascular function and reverse shock [1]. Current sepsis guidelines recommend resuscitation with intravascular fluid administration in association with inotropes and vasopressors to maintain organ perfusion [2]. Dobutamine is recommended as first-line inotropic agent and should be administered when low cardiac output or signs of hypoperfusion persist after adequate fluid resuscitation and perfusion pressure have been achieved [2]. However, the efficacy of dobutamine in patients with heart failure has not been fully demonstrated and concerns on its use are still present [3]. Although dobutamine improves perfusion and increases oxygen delivery (DO₂), its impact on survival in septic shock patients is limited, with guideline recommendations based mainly on the landmark study by Rivers et al. [4]. Recently, Wilkman et al. [5] reported that the use of inotropes, particularly dobutamine, in septic shock was associated with increased 90-day mortality. In explaining the lack of outcome benefit [3, 5], several aspects need to be taken into account. First, the need of inotropic support may simply represent an expression of disease severity rather than the cause of a poor outcome. Second, whereas the treatment of impaired cardiac output should be tailored based on the etiological mechanism of the cardiovascular dysfunction, the current guidelines recommend the use of inotropes without differentiating the underlying causes of impaired left ventricular (LV) stroke volume [2, 6]. In addition, the majority of cardiovascular monitoring instruments provide data almost exclusively on cardiac output and pressures. This approach may potentially increase the number of patients who may be harmed by inotrope administration (Fig. 1). Finally, the beneficial short-term effect of enhanced contractility by cAMP-increasing drugs (e. g., dobutamine, milrinone) is, at least partly, abolished by the increased energy consumption, the worsening of ventricular relaxation and the direct cardiomyocyte toxicity [1, 7–10].

Pathophysiology of microcirculatory dysfunction and the pathogenesis of septic shock

Multiple experimental and human trials have shown that microcirculatory alterations are frequent in sepsis. In this review, we discuss the various mechanisms that are potentially involved in their development and the implications of these alterations. Endothelial dysfunction, impaired inter-cell communication, altered glycocalyx, adhesion and rolling of white blood cells and platelets, and altered red blood cell deformability are the main mechanisms involved in the development of these alterations. Microcirculatory alterations increase the diffusion distance for oxygen and, due to the heterogeneity of microcirculatory perfusion in sepsis, may promote development of areas of tissue hypoxia in close vicinity to well-oxygenated zones. The severity of microvascular alterations is associated with organ dysfunction and mortality. At this stage, therapies to specifically target the microcirculation are still being investigated.