Differential hemodynamic effects of levosimendan in a porcine model of neonatal hypoxia-reoxygenation

The Effect of Levosimendan on Phosphine-Induced Nephrotoxicity: Biochemical and Histopathological Assessment

BACKGROUND

Aluminum phosphide (AlP) toxicity is associated with a high risk of death due to heart, liver, and kidney failure as the target organs. Phosphine gas released due to the ingestion is the main factor involved in the multi-organ failure with various mechanisms. Levosimendan (LEV) is a calcium sensitizer with a pleiotropic effect on multiple organs. This study aimed to investigate whether LEV can alleviate AlP-induced nephrotoxicity in the rat model.

METHOD

Six groups included control group (almond oil only), sole LEV group (48 µg/kg), AlP group (LD50=10 µg/kg), and the poisoned groups treated with LEV at doses of 12, 24, and 48 µg/kg 30 min after AlP gavage. After 24 hours of treatment, serum and kidney samples were taken for biochemical and histopathological analyses.

RESULT

Biochemical analysis of the AlP group showed that the activity of complexes I, II, and IV was significantly reduced, while the levels of lipid peroxidation (LPO) and reactive oxygen species (ROS), lactate, and myeloperoxidase (MPO) activity significantly increased. Also, AlP reduced live renal cells and elevated necrosis. However, the levels of serum creatinine and blood urea nitrogen were not affected by the poisoning. LEV co-treatment could increase mitochondrial complex activity and reduce MPO activity, LPO, ROS, and lactate levels. Additionally, the histopathological analysis showed the detrimental effects of AlP on kidney tissue, which was mitigated by LEV administration.

CONCLUSION

Our findings showed that LEV can potentially improve oxidative stress, imbalance in the redox status, necrosis, and pathological injuries in kidney tissue following AlP-poisoning.

The Use of Cardiotonic Drugs in Neonates

There is a distinct lack of age-appropriate cardiotonic drugs, and adult derived formulations continue to be administered, without evidence-based knowledge on their dosing, safety, efficacy, and long-term effects. Dopamine remains the most commonly studied and prescribed cardiotonic drug in the neonatal intensive care unit (NICU), but evidence of its effect on endorgan perfusion still remains. Unlike adult and pediatric critical care, there are significant gaps in our knowledge on the use of various cardiotonic drugs in various forms of circulatory failure in the NICU.

Cardiovascular Supportive Therapies for Neonates With Asphyxia - A Literature Review of Pre-clinical and Clinical Studies

Asphyxiated neonates often have hypotension, shock, and poor tissue perfusion. Various "inotropic" medications are used to provide cardiovascular support to improve the blood pressure and to treat shock. However, there is incomplete literature on the examination of hemodynamic effects of these medications in asphyxiated neonates, especially in the realm of clinical studies (mostly in late preterm or term populations). Although the extrapolation of findings from animal studies and other clinical populations such as children and adults require caution, it seems appropriate that findings from carefully conducted pre-clinical studies are important in answering some of the fundamental knowledge gaps. Based on a literature search, this review discusses the current available information, from both clinical studies and animal models of neonatal asphyxia, on common medications used to provide hemodynamic support including dopamine, dobutamine, epinephrine, milrinone, norepinephrine, vasopressin, levosimendan, and hydrocortisone.

Comparison of the Effects of Levosimendan Dobutamine and Vasodilator Therapy on Ongoing Myocardial Injury in Acute Decompensated Heart Failure

BACKGROUND

Cardiac troponins (cTn) are reliable and the most sensitive biomarker in the setting of acute decompensated heart failure (ADHF). Acute decompensated heart failure is usually associated with worsening chronic heart failure, and it may be caused by ongoing minor myocardial cell damage that may occur without any reported precipitating factors.

METHODS

We compared the short-term effect of levosimendan (LEV), dobutamine (DOB), and vasodilator treatment (nitroglycerin [NTG]) on myocardial injury with hemodynamic, neurohumoral, and inflammatory indicators. One hundred twenty-two patients with a mean age of 66 ± 9 years were treated with LEV (n = 40), DOB (n = 42), and NTG (n = 40) and examined retrospectively. Blood samples (cTnI, N-terminal probrain natriuretic peptide [NT-proBNP], highly sensitive C-reactive protein [HsCRP], and others), left ventricular ejection fraction (LVEF), systolic pulmonary artery pressure (sPAP), and 6-minute walk distance (6MWD) were compared before and after treatment.

RESULTS

At admission, detectable levels of cTnI were observed in 53% of patients (≥0.05 ng/mL). Serial changes in the mean cTnI levels were not significantly different between the groups (LEV 0.04 ± 0.01 to 0.03 ± 0.01 ng/mL; DOB 0.145 ± 0.08 to 0.08 ± 0.03 ng/mL; NTG 0.1 ± 0.03 to 0.09 ± 0.02 ng/mL; overall P = .859). Favourable effects on the NT-proBNP, sPAP values, LVEF, 6MWD, and HsCRP were observed overall, especially in the LEV groups.

CONCLUSION

Beneficial effects of short-term use of LEV, DOB, and NTG on ongoing myocardial injury were demonstrated. These findings can be attributed to the anti-ischemic properties as well as the hemodynamic, neurohumoral, and functional benefits from the positive inotropes, especially LEV, in patients with ADHF.

[Use of levosimendan in children]

Levosimendan is a calcium-sensitizing drug with positive inotropic properties. As an inodilator, this molecule also has a vasodilation effect. While its efficacy has been demonstrated in the adult in the context of cardiac surgery, its pediatric use is still not widespread. Many studies have shown its safety of use in children, including in the newborn. Across the world, a growing number of teams use levosimendan to treat both acute and chronic heart failure. Through a review of the literature, we describe its pharmacodynamic effects, its current applications, and its perspectives of use in children.

Controversies in neonatal resuscitation

Despite recent advances in perinatal medicine and in the art of neonatal resuscitation, resuscitation strategy and treatment methods in the delivery room should be individualized depending on the unique characteristics of the neonate. The constantly increasing evidence has resulted in significant treatment controversies, which need to be resolved with further clinical and experimental research.

Milrinone is preferred to levosimendan for mesenteric perfusion in hypoxia-reoxygenated newborn piglets treated with dopamine

INTRODUCTION

There is little information regarding the comparative hemodynamic effects of adding milrinone or levosimendan to dopamine infusion in hypoxia-reoxygenated (H-R) newborns.

RESULTS

Severely hypoxic piglets had cardiogenic shock with depressed cardiac index (CI) and mean arterial pressure (MAP). The hemodynamics deteriorated gradually after initial recovery upon reoxygenation. Heart rate and CI improved with milrinone (D+M) and levosimendan (D+L) administration (P < 0.05 vs. control). Both regimens improved carotid arterial flow and carotid vascular resistance; D+M additionally improved superior mesentric arterial flow (all P < 0.05 vs. control). No effect was found on renal arterial flow or elevated lactate state with either regimen. D+M piglets also had a lower myocardial oxidized/reduced glutathione ratio (P < 0.05 vs. control).

DISCUSSION

In conclusion, adding milrinone or levosimendan to dopamine similarly improved systemic hemodynamics in H-R newborn piglets. Milrinone also improved mesenteric perfusion and attenuated myocardial oxidative stress.

METHODS

Twenty-eight piglets (1-4 d, 1.5-2.5 kg) were instrumented for continuous monitoring of systemic MAP and pulmonary arterial pressure (PAP), CI, and carotid, superior mesenteric, and renal arterial flows. Piglets were randomized with blinding to sham-operated, H-R control (saline), and H-R dopamine (10 μg/kg/min) with D+M or D+L groups. H-R piglets underwent H-R followed by 2 h of drug infusion after reoxygenation. Tissue was collected for biochemical/oxidative stress testing and histological analysis.