Will my patient benefit from additional IV fluid?
Clinicians have always wanted to know if additional IV fluid will improve perfusion, which has traditionally been indirectly assessed by measuring blood pressure, end organ function (urine output, mentation) or biomarkers such as lactate.
Today, with Cheetah’s ability to noninvasively measure stroke volume, we can directly answer this question via a dynamic assessment.
What is a dynamic assessment?
A dynamic assessment evokes a simple physiologic patient response by challenging the patient with a small volume of intravascular fluid and directly observing the heart’s ventricular response. If a patient’s stroke volume or cardiac output increases by at least 10%, this is highly predictive of significant cardiac output (and perfusion) increase with additional IV fluid administration. A response of less than 10% is predictive that the patient is unlikely to increase perfusion with additional fluid.
Only approximately 50% of hemodynamically unstable patients improve perfusion with IV fluid!
Multiple studies demonstrate that only 40 to 72% of hemodynamically unstable patients benefit from IV fluid by increasing cardiac output and improving perfusion1. In nearly half of hemodynamically unstable patients, additional IV fluid does not improve perfusion, and may cause harm1. Only recently, with new technologies such as the CHEETAH NICOM and Starling SV, can we routinely, directly and noninvasively assess stroke volume and cardiac output changes in response to fluid therapy.
Additionally, we are learning today that getting fluid right – really matters!
Clinicians have always known that under-resuscitating a patient can lead to complications, just as too much IV fluid can lead to volume overload. New and continued research continues to prove that getting fluid just right, is very important2. This is particularly true in sepsis and in surgery patients 3,4.
1. Michard F and Teboul JL. Predicting fluid responsiveness in ICU patients: a critical analysis of the evidence. Chest. 2002; 121:2000-2008.
2. Marik P and Cavallazzi R. Does central venous pressure predict fluid responsiveness? An updated meta-analysis and a plea for some common sense. Crit Care Med 2013; 41: 1774-1778.
3. Kelm DJ, et al. Fluid overload in patients with severe sepsis and septic shock treated with early goal-directed therapy is associated with increased acute need for fluid-related medical interventions and hospital death. Shock 2015; 43:68-73.
4. Corcoran T et al. Perioperative Fluid Management Strategies in Major Surgery: A stratified meta-analysis. Anesth Analg 2012; 114: 640-651.