The Vasoactive-Inotropic Score and Levosimendan: Time for LVIS?

Abstract

Three recent randomized controlled trials1Momeni M. Rubay J. Matta A. et al.Levosimendan in congenital cardiac surgery: A randomized, double-blind clinical trial.J Cardiothorac Vasc Anesth. 2011; 25: 419-424Abstract Full Text Full Text PDF PubMed Scopus (63) Google Scholar, 2Ricci Z. Garisto C. Favia. I et al.Levosimendan infusion in newborns after corrective surgery for congenital heart disease: Randomized controlled trial.Intensive Care Med. 2012; 38: 1198-1204Crossref PubMed Scopus (43) Google Scholar, 3Lechner E. Hofer A. Leitner-Peneder G. et al.Levosimendan versus milrinone in neonates and infants after corrective open-heart surgery: A pilot study.Pediatr Crit Care Med. 2012; ([Epub ahead of print])PubMed Google Scholar evaluated the safety and efficacy of levosimendan in children with congenital heart disease undergoing cardiac surgery. All these papers concluded that levosimendan was safe and contributed to improvement of cardiac function and inotropic support optimization. From these initial experiences following levosimendan use in adult critically ill patients, indications for this drug in the pediatric setting is expected to increase. Recently, Davidson et al4Davidson J. Tong S. Hancock H. et al.Prospective validation of the vasoactive-inotropic score and correlation to short-term outcomes in neonates and infants after cardiothoracic surgery.Intensive Care Med. 2012; 38: 1184-1190Crossref PubMed Scopus (123) Google Scholar prospectively compared the vasoactive-inotropic score (VIS) and inotrope score in infants after cardiovascular surgery, as mathematical measures for evaluating vasoactive drug administration, and, consequently, the hemodynamic condition of patients. At all assessed time points, VIS was shown to be more predictive of poor short-term outcome than inotrope score. Interestingly, the authors observed that from a clinical perspective, a high VIS at 48 hours postoperatively achieved the best performance as a predictor for poor outcome. VIS is calculated as dopamine dose (mcg/kg/min)+dobutamine dose (mcg/kg/min)+100×epinephrine dose (mcg/kg/min)+10×milrinone dose (mcg/kg/min)+10,000×vasopressin dose (U/kg/min)+100×norepinephrine dose (mcg/kg/min). We noticed that levosimendan is not currently included in the VIS calculation. In our opinion, the time has come for a modified version of VIS also including levosimendan input in the formula (levosimendan VIS [LVIS]). It should be mentioned that the hypothetical application of levosimendan to the VIS formula should be prolonged for a week (3 or 4 days after the drug infusion has been stopped, due to its prolonged metabolite activity). We propose to include levosimendan with a factor of 50 (to achieve a contribution to VIS similar to milrinone); milrinone 0.5 to 1 mcg/kg/min has a VIS weight from 5 to 10. Similarly, a levosimendan dose of 0.1 to 0.2 mcg/kg/min would achieve a LVIS formula weight of 5 to 10. We tried to apply this concept to a recent study from our group2Ricci Z. Garisto C. Favia. I et al.Levosimendan infusion in newborns after corrective surgery for congenital heart disease: Randomized controlled trial.Intensive Care Med. 2012; 38: 1198-1204Crossref PubMed Scopus (43) Google Scholar and found that the significant VIS differences between the levosimendan group and controls would change dramatically; significant LVIS differences are not present between the 2 groups (Fig 1A and B). We suggest authors and reviewers take into account the following LVIS in future pediatric papers dealing with levosimendan: LVIS = dopamine dose (mcg/kg/min)+dobutamine dose (mcg/kg/min)+100×epinephrine dose (mcg/kg/min)+10×milrinone dose (mcg/kg/min)+10,000×vasopressin dose (U/kg/min)+100×norepinephrine dose (mcg/kg/min)+50×levosimendan dose (mcg/kg/min).