Isooncotic human albumin
The theoretical value of fluid therapy with isooncotic human albumin over crystalloids is multifactorial [20, 27, 42]. Physiologically, albumin is the primary determinant of intravascular osmotic pressure, aids in the transport of several compounds, serves as a native free radical scavenger and possess both anti-inflammatory and antioxidant properties [27, 42-44].
As a volume expander, isooncotic human albumin is theorized to provide intravascular volume expansion more efficiently than crystalloids [24]. Colloids are hypothesized to remain in the intravascular space for a more sustained period of time [25, 45], and provide volume expansion without a significant chloride burden when compared to both isotonic saline and balanced crystalloid solutions [20, 27]. The latter is particularly relevant given the growing body of evidence that indicates elevated chloride levels are harmful in the critically ill [46-48].
The potential risks of resuscitation in the ICU with human albumin has also been investigated [49-51]. When compared to crystalloids, there is evidence to suggest resuscitation with human albumin may be related to coagulation abnormalities [50], increased need for blood transfusions [50, 52], anaphylactoid reactions [40], and acute kidney injury [51, 53]. Moreover, there has been no consistent evidence that suggests resuscitation with albumin improves mortality, number of ventilator free days or length of hospital stay [52]. In addition to these potential clinical sequelae, human albumin costs significantly more in comparison to saline and balanced intravenous fluids [12, 49, 52].