Digital blood flow and plasma endothelin concentration in clinically endotoxemic horses

• Published in: American journal of veterinary research Vol. 66; no. 4; pp. 630 - 636
• Main Authors: Menzies-Gow, N.J, Bailey, S.R, Stevens, K, Katz, L, Elliott, J, Marr, C.M
• Format: Journal Article
• Language: English
• Published: United States 01.04.2005
• Subjects: Animals; Blood Chemical Analysis - veterinary; blood flow; blood plasma; Blood Pressure - physiology; Body Temperature - physiology; digestive system diseases; Digestive System Surgical Procedures - adverse effects; Digestive System Surgical Procedures - veterinary; endothelin; Endothelin-1 - blood; endotoxemia; Endotoxemia - blood; Endotoxemia - etiology; Endotoxemia - physiopathology; Endotoxemia - veterinary; Female; Follow-Up Studies; Foot - blood supply; Foot - diagnostic imaging; Gastrointestinal Diseases - complications; Gastrointestinal Diseases - surgery; Gastrointestinal Diseases - veterinary; Heart Rate - physiology; horse diseases; Horse Diseases - blood; Horse Diseases - physiopathology; Horses; laminitis; Leukocyte Count - veterinary; limbs (animal); lipopolysaccharides; Lipopolysaccharides - blood; longitudinal studies; Male; mortality; Respiration; Surveys and Questionnaires; Ultrasonography; vasoconstrictor agents
• ISSN: 0002-9645; 1943-5681
• DOI: 10.2460/ajvr.2005.66.630

To measure plasma endothelin-1 (ET-1) concentrations and digital blood flow in clinically endotoxemic horses. 36 adult horses that underwent emergency celiotomy for primary gastrointestinal tract disease. On days 2 and 5 following surgery, Doppler ultrasonographic digital arterial blood flow measurements were obtained. Hematologic and biochemical analyses were performed, and plasma concentrations of ET-1 and endotoxin (lipopolysaccharide) were determined. A scoring system based on 9 clinical variables was used to assign horses to group B (quartile with greatest cumulative score) or group A (remaining 3 quartiles). Follow-up at 2.5 years was obtained by telephone questionnaire. For all horses on day 2, median (interquartile values) plasma ET-1 concentrations were 1.4 (0.8, 1.7) pg/mL, whereas on day 5, plasma ET-1 concentrations were 1.0 (0.5, 1.6) pg/mL. On day 2, digital blood flow was 0.057 (0.02, 0.07) mL/min in group A horses and 0.035 (0.02, 0.03) mL/min in group B horses. On day 5, plasma ET-1 concentration was significantly (73%) higher in group B horses, compared with group A horses. Thirty of 36 horses were alive at 2.5 years; group A horses were more likely to have survived (odds ratio, 25; 95% confidence interval, 2.4 to 262). Significant associations were found between an increase in digital pulses, hoof wall temperatures, or both and increased digital blood flow (0.14 vs 0.04 mL/min) on day 2 and increased digital arterial diameter (0.32 vs 0.23 cm) on day 5. Horses with more severe endotoxemia had decreased digital blood flow, increased plasma ET-1 concentrations, and decreased long-term survival.