Perioperative fluid therapy: a statement from the international Fluid Optimization Group

Abstract

Background: Perioperative fluid therapy remains a highly debated topic. Its purpose is to maintain or restore effective circulating blood volume during the immediate perioperative period. Maintaining effective circulating blood volume and pressure are key components of assuring adequate organ perfusion while avoiding the risks associated with either organ hypo- or hyperperfusion. Relative to perioperative fluid therapy, three inescapable conclusions exist: overhydration is bad, underhydration is bad, and what we assume about the fluid status of our patients may be incorrect. There is wide variability of practice, both between individuals and institutions. The aims of this paper are to clearly define the risks and benefits of fluid choices within the perioperative space, to describe current evidence-based methodologies for their administration, and ultimately to reduce the variability with which perioperative fluids are administered.

Methods: Based on the abovementioned acknowledgements, a group of 72 researchers, well known within the field of fluid resuscitation, were invited, via email, to attend a meeting that was held in Chicago in 2011 to discuss perioperative fluid therapy. From the 72 invitees, 14 researchers representing 7 countries attended, and thus, the international Fluid Optimization Group (FOG) came into existence. These researches, working collaboratively, have reviewed the data from 162 different fluid resuscitation papers including both operative and intensive care unit populations. This manuscript is the result of 3 years of evidence-based, discussions, analysis, and synthesis of the currently known risks and benefits of individual fluids and the best methods for administering them.

Results: The results of this review paper provide an overview of the components of an effective perioperative fluid administration plan and address both the physiologic principles and outcomes of fluid administration.

Conclusions: We recommend that both perioperative fluid choice and therapy be individualized. Patients should receive fluid therapy guided by predefined physiologic targets. Specifically, fluids should be administered when patients require augmentation of their perfusion and are also volume responsive. This paper provides a general approach to fluid therapy and practical recommendations.

Keywords: Fluid responsiveness; Fluid resuscitation; Goal-directed fluid therapy; Perioperative fluids.

Figure 1

Perspective of the anesthesiologist’s tools (fluid and drugs) and the physiologic targets of these tools (blood volume, the heart, and blood vessels). The heart has two components (contractility and rate), and the blood vessels have two major characteristics (compliance and resistance). It is blood volume, heart, and blood vessels that produce pressure, flow, and oxygen delivery, while the intermediate physiologic functions and their metrics provide a means of assessing the cardiovascular state and how effective fluids are likely to be.

Figure 2

Goal-directed hemodynamic algorithm to guide intraoperative volume therapy in major abdominal surgeries: (a) initial assessment and treatment and (b) further intraoperative optimization [ 58 ] (used per BioMed Central’s creative commons license). PPV, pulse pressure variation; CI, cardiac index; MAP, mean arterial pressure.

Figure 3

A rational approach to intraoperative monitoring. A useful approach for assessing the needed level of hemodynamic monitoring based on the patient status, surgical risk, and clinical management requirements (what are my management needs?). NIBP, noninvasive blood pressure; ECG, electrocardiogram; A-line, arterial catheterization; NICP, noninvasive continuous pressure; CVC, central venous catheter; ECHO, transthoracic or transesophageal echocardiography; PAC, pulmonary artery catheter; ScVO₂, central venous oxygen saturation; MVO₂, mixed venous oxygen saturation; PCA, pulse contour analysis; BioImp, bioimpedance or bioreactance.