Goal-Directed Therapy:
Optimizing fluid management in your patient
Michael R. Pinsky, MD

Surgical trauma often exposes patients to periods of cardiovascular insufficiency, either because of anesthesia-induced loss of vasomotor tone and baroreceptor responsiveness, or because of blood loss and mechanical obstruction to blood flow. In all cases, cardiac output will fall and if the heart rate remains constant, stroke volume will fall as well. If there is sustained cardiovascular insufficiency with inadequate O2 delivery to the tissues, then end-organ dysfunction may occur, resulting in increased patient morbidity and mortality. Although most surgery does not result in profound tissue hypoperfusion causing organ system function, some degree of hypoperfusion does occur. Since surgical stress also stimulates a vigorous cytokine storm, the combination of relative hypoperfusion and immune modulation will alter the microcirculation, causing subclinical injury.

Until ~20 years ago, it was felt that these concerns were primarily academic and did not affect patient outcomes. However, in the 1980s, William Shoemaker and colleagues documented that a surgery-associated reduction of global oxygen delivery (DO2), calculated as the product of cardiac output and arterial oxygen content, resulted in a deficiency relative to the preoperative basal oxygen delivery/oxygen consumption. Importantly, if this decreased DO2 caused O2 consumption to also fall, then it was assumed to reflect a surgery-induced "oxygen delivery debt." The magnitude of this oxygen debt was uniquely associated with the patient outcome in that both morbidity and mortality were associated with the highest levels of oxygen debt. Although their initial clinical trial to target what they referred to as "survivor levels" of DO2 was successful, subsequent trails were uniformly negative or actually resulted in a worse outcome. It was presumed at the time that the risks associated with aggressive resuscitation and vasoactive drug therapies needed to achieve these levels of DO2 could be detrimental.

Panel Discussion
Optimizing fluid management: Opinions from the Experts
Moderator: Michael R. Pinsky, MD
Panelists: Scott Brudney, MB, BCh
Maxime Cannesson, MD, PhD
Paul Marik, MBBCh
Gabriel Mena, MD
Rupert Pearse, MD
John Gallagher, MSN, RN, RRT

Rapid Response.

This one-hour computer based learning module has been designed for the bedside healthcare provider and members of the RRT as a primer on the importance of early identification of a patient in crisis, effective team communication during a crisis and rapid assessment and stabilization of the patient.