Dose response effects of hypertonic saline and dextran on cardiovascular responses and plasma volume expansion in sheep.

Abstract

Despite the established efficacy of 7.5% NaCl/6% dextran-70 in the treatment of hypovolemia, the optimal formulation of a hyperosmotic/hyperoncotic small volume resuscitation solution has yet to be defined. The present study investigates the cardiovascular effects of hypertonic saline ranging from 3.75%-25% NaCl (HS) and dextran-70 (D-70) ranging from 3 to 24%. HS and D-70 were studied alone or in specific combinations at a dose of 4 mL/kg, in euvolemic sheep. Blood samples were collected before, during and up to 60 min after infusion of the test solutions. Dose-dependent effects of HS were immediate increases in cardiac output (CO) of 30-85%, falling to 10-35% over baseline after 60 min. HS concentrations over 3.75% significantly reduced systemic vascular resistance, but HS had no significant effect on mean arterial pressure (MAP). Plasma volume (PV) expansion with HS was an immediate, but transient increase of 12-35%. Infusion of D-70 induced sustained 10-20% increases in CO and 10-30% increases in PV, peaking 10 min post-infusion. D-70 also resulted in small (5-12 mmHg) increases in MAP. Cardiovascular effects of D-70 correlated with a dose-dependent increase in plasma dextran concentrations. All HS solutions significantly increased plasma Na, which peaked at > or = 200 mEq/L in the 25% group. The effects of D-70 and HS combined were additive on PV expansion and CO. These data indicate that concentrations of HS and D-70 which are higher than those currently used have a greater capability for expanding PV, but use of HS > 7.5% may be limited by resulting hypernatremia.

• Authors: M A Dubick, J M Davis, T Myers, C E Wade, G C Kramer
• Journal: Shock (Augusta, Ga.) (Shock) Vol. 3 Issue 2 Pg. 137-44 (Feb 1995) ISSN: 1073-2322 [Print] United States
• PMID: 7538433 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Dextrans
• Electrolytes
• Hypertonic Solutions
• Saline Solution, Hypertonic

Topics

• Animals
• Blood Pressure (drug effects)
• Cardiac Output (drug effects)
• Dextrans (blood, pharmacology)
• Dose-Response Relationship, Drug
• Electrolytes (blood)
• Female
• Hypertonic Solutions (pharmacology)
• Plasma Volume (drug effects, physiology)
• Saline Solution, Hypertonic (pharmacology)
• Sheep
• Time Factors
• Vascular Resistance (drug effects)