Acute Intravascular Volume Expansion with Rapidly Administered Crystalloid or Colloid in the Setting of Moderate Hypovolemia

• Published in: Anesthesia and analgesia Vol. 96; no. 6; pp. 1572 - 1577
• Main Authors: McIlroy, David R., Kharasch, Evan D.
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD International Anesthesia Research Society 01.06.2003; Lippincott
• Subjects: Adult; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Blood Volume - drug effects; Blood. Blood and plasma substitutes. Blood products. Blood cells. Blood typing. Plasmapheresis. Apheresis; Colloids - therapeutic use; Cross-Over Studies; Crystalloid Solutions; Female; Hematocrit; Humans; Hydroxyethyl Starch Derivatives - therapeutic use; Hypovolemia - physiopathology; Hypovolemia - therapy; Isotonic Solutions - therapeutic use; Male; Medical sciences; Plasma Substitutes - therapeutic use; Prospective Studies; Ringer's Solution; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; Human; Ringer lactate; Intravenous administration; Healthy subject; Hypovolemia; Intravascular space; Male; Colloid; Plasma substitute; Rapid technique; Blood volume; Crystalloid solution; Perfusion; Starch(hydroxyethyl); Comparative study
• ISSN: 0003-2999
• DOI: 10.1213/01.ANE.0000061460.59320.B0

Although the distribution of various crystalloid and colloid solutions at equilibrium has been well established, the acute peak expansion of intravascular volume that can be achieved with the rapid administration of crystalloid or colloid is unknown. We studied eight healthy male subjects in a two-part crossover trial designed to assess the maximal increase in intravascular volume achieved with 1000 mL of lactated Ringer’s solution compared with the same volume of 6% Hetastarch. Subjects were made moderately hypovolemic by the withdrawal of 900 mL of blood, and then the crystalloid or colloid solution was rapidly infused over 5–7 min. Serial dilution of hematocrit was measured every 5 min for 30 min to determine changes in blood volume. Peak expansion of intravascular volume with lactated Ringer’s solution was 630 ± 127 mL, occurring immediately the rapid infusion was complete, whereas the peak expansion of intravascular volume with 6% Hetastarch was 1123 ± 116 mL and occurred 5 min after the completion of the fluid infusion. The results were significantly different (P < 0.001). These results would suggest that even for very short periods of time, rapid infusion of colloid significantly more effectively increases blood volume and, by inference, cardiac output than the same volume of crystalloid, even if the crystalloid is administered very rapidly. IMPLICATIONSUnder conditions of moderate hypovolemia, the maximal acute intravascular volume expansion with the rapid infusion of 1000 mL of lactated Ringer’s solution is slightly more than half that achieved with the same volume of 6% Hetastarch.