ABSTRACTS from 16th International COnference on ... - CRRT Online

C03
Critical Care Pharmacology: Vasopressors, and Inotropes
Educational Objectives:
1. Provide an understanding of what inotropic agents and vaspressors are
Peter Pickkers MD, PhD
4:00-5:30
Tuesday, February 14
2. Understand the various syndromes in which vasopressors and inotropes need to be used
3. Review current literature on vasopressors and inotropic agents, of both established and new agents.
Content Description:
Preload is the stretch of a muscle immediately prior to contraction. In the context of human pathophysiology,
preload is the left ventricular end diastolic fibre length which is proportional to left ventricular end diastolic volume
(LVEDV). This in turn is proportional to LVEDP. Clinically this sometimes is measured by venous pressures
(JVP or CVP). The famous Starling curve relates an increase in preload to an increase in force of contraction
(increasing LVEDV increases cardiac output).
Afterload is the pressure developed in the myocardium wall during systole. A decrease in afterload (vasodilatation)
will increase the cardiac output. and often vice versa.
A positive inotropic agent will increase force of contraction independent of preload and afterload. A vasopressor
agent is one that will increase vascular tone and hence increase blood pressure.
It is important to conceptually differentiate these two phenomena, but in the clinical situation one agent may
have both effects.
Shock can be defined as inadequate tissue oxygenation. The various causes of shock have been divided into 4
categories:- hypovolaemic, distributive, cardiogenic and obstructive. (Note, clinically there may sometimes be
overlap or a combination). Distributive shock is most often <strong>from</strong> sepsis. The most common use of vasopressors
in ICU is in septic shock, as it is for the use of inotropic agents.
Whilst there is no ideal inotropic agent, many have been used for septic shock. This holds too for vaspressor
agents too, The various agents used clinically will be reviewed as will their “side effects”.
It is probably safe to say most commonly dobutamine and norepinephrine are used in septic shock, but clinical
data of new drugs is becoming available. Apart <strong>from</strong> the conventional agents, mechanism of action and clinical
effects of vasopressin, potassium channel blockers and levosimendan will be presented.
Suggested Reading:
1. De Backer D, Aldecoa C, Njimi H, Vincent JL. Dopamine versus norepinephrine in the treatment of septic
shock: A meta-analysis. Crit Care Med. 2011 Oct 27. [Epub ahead of print]
2. Annane D, Vignon P, Renault A, Bollaert PE, Charpentier C, Martin C, Troché G, Ricard JD, Nitenberg G,
Papazian L, Azoulay E, Bellissant E; CATS Study Group. Norepinephrine plus dobutamine versus epinephrine
alone for management of septic shock: a randomised trial. Lancet. 2007 Aug 25;370(9588):676-84.
3. Landoni G, Biondi-Zoccai G, Greco M, Greco T, Bignami E, Morelli A, Guarracino F, Zangrillo A. Effects of
levosimendan on mortality and hospitalization. A meta-analysis of randomized controlled studies. Crit Care Med.
2012 Feb;40(2):634-46.
4. Doorduin J, Heunks LM, Pickkers P. How can you mend a broken heart?. Crit Care Med. 2012
Feb;40(2):702-3.
5. Papp Z, Edes I, Fruhwald S, De Hert SG, Salmenperä M, Leppikangas H, Mebazaa A, Landoni G, Grossini E,
Caimmi P, Morelli A, Guarracino F, Schwinger RH, Meyer S, Algotsson L, Wikström BG, Jörgensen K,
Filippatos G, Parissis JT, González MJ, Parkhomenko A, Yilmaz MB, Kivikko M, Pollesello P, Follath F.
Levosimendan: Molecular mechanisms and clinical implications Consensus of experts on the mechanisms of
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