Cardiovascular and pulmonary effects of hetastarch plus hypertonic saline solutions during experimental endotoxemia in anesthetized horses.
BACKGROUND
Small volume resuscitation has been advocated as a beneficial therapy for endotoxemia in horses but this therapy has not been investigated in a prospective manner. The objective of this study was to determine the cardiopulmonary effects of small-volume resuscitation using hypertonic saline solution (HSS) plus Hetastarch (HES) during experimental endotoxemia in anesthetized horses.


OBJECTIVE
Treatment of horses with induced endotoxemia using HES-HSS does not alter the response of various cardiopulmonary indices when compared to treatment with either small- or large-volume isotonic crystalloid solutions.


METHODS
Eighteen healthy horses were randomly assigned to 1 of 3 groups. Anesthesia was maintained with halothane. Endotoxemia was induced by administering 50 microg/kg of Escherichia coli endotoxin IV. The horses were treated over 30 minutes with 15 mL/kg of balanced polyionic crystalloid solution (control), 60 mL/kg of balanced polyionic crystalloid solution (ISO), or 5 mL/kg of HSS followed by 10 mL/kg of HES (HSS-HES).


METHODS
Prospective randomized trial.


RESULTS
Cardiac output (CO) after endotoxin infusion increased significantly (P < .05) from baseline in all groups, whereas mean central venous pressure increased significantly (P < .05) in the ISO group only. Mean pulmonary artery pressure increased from baseline (P < .05) in horses treated with isotonic fluids and HSS-HES. There was no effect of treatment with HSS-HES on CO, systemic vascular resistance (SVR), mean arterial pressure, blood lactate concentrations, or arterial oxygenation.


CONCLUSIONS
The use of HSS-HES failed to ameliorate the deleterious hemodynamic responses associated with endotoxemia in horses. The clinical value of this treatment in horses with endotoxemia remains unconfirmed.
Pantaleon
Lucas G
LG
Marion duPont Scott Equine Medical Center, Virginia/ Maryland Regional College of Veterinary Medicine, Leesburg, VA, USA. lucaspantaleon@hotmail.com
Furr
Martin O
MO
McKenzie
Harold C
HC
Donaldson
Lydia
L
D000136:Acid-Base Equilibrium; D000758:Anesthesia / Q000662:veterinary; D000818:Animals; D001784:Blood Gas Analysis / Q000662:veterinary; D001794:Blood Pressure; D001810:Blood Volume; D002302:Cardiac Output / Q000187:drug effects; D019446:Endotoxemia / Q000628:therapy / Q000662:veterinary*; D006438:Hemodilution / Q000662:veterinary; D006734:Horse Diseases / Q000188:drug therapy*; D006736:Horses; D006895:Hydroxyethyl Starch Derivatives / Q000494:pharmacology*; D010952:Plasma Substitutes / Q000494:pharmacology*; D011446:Prospective Studies; D012462:Saline Solution, Hypertonic / Q000494:pharmacology*; D012772:Shock, Septic / Q000628:therapy / Q000662:veterinary; D016896:Treatment Outcome; D014655:Vascular Resistance
D006895:Hydroxyethyl Starch Derivatives; D010952:Plasma Substitutes; D012462:Saline Solution, Hypertonic