Only 50% of hemodynamically unstable patients will improve their hemodynamics in response to a fluid bolus. However, because excessive fluid administration can lead to organ edema and dysfunction, it is important to give hemodynamically unstable patients only the necessary amount of fluids to improve their hemodynamics.
There are two general categories of assessing a patient's response to volume administration; static and dynamic assessments (see referenced article below):
Static assessment (generally unreliable, but traditionally used):
Physical exam (dry mucus membranes, cool extremities, etc.)
Urine output
Blood pressure
Central venous pressure via central-line
Dynamic assessment (more reliable but more labor intensive)
Pulse Pressure Variation
IVC Distensibility Index
End-expiratory occlusion test
Passive Leg-Raise
There is no simple way to accurately determine the need for a fluid bolus however the integration of the techniques above can help the clinician make better decisions.
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