Hemodynamic Parameters Change Earlier Than Tissue Oxygen Tension in Hemorrhage

• Published in: The Journal of surgical research 2010-05, Vol.160 (2), p.288-293
• Main Authors: Pestel, Gunther J., M.D, Fukui, Kimiko, M.D, Kimberger, Oliver, M.D, Hager, Helmut, M.D, Kurz, Andrea, M.D, Hiltebrand, Luzius B., M.D
• Format: Article
• Language: English
• Subjects: Acute Disease; Animals; Biological and medical sciences; bleeding; Blood Pressure - physiology; Blood Volume - physiology; Cardiac Output - physiology; Cardiovascular system; Colon - blood supply; Colon - metabolism; difference in pulse pressure; Disease Models, Animal; dPP; General aspects; Heart Arrest - metabolism; Heart Arrest - physiopathology; hemodynamics; Hemodynamics - physiology; hemorrhage; Hemorrhage - metabolism; Hemorrhage - physiopathology; Hypovolemia - metabolism; Hypovolemia - physiopathology; Investigative techniques, diagnostic techniques (general aspects); Jejunum - blood supply; Jejunum - metabolism; Laser-Doppler Flowmetry; Liver - blood supply; Liver - metabolism; Medical sciences; Microcirculation - physiology; monitoring; Oxygen - metabolism; pigs; pulse pressure variation; Surgery; Sus scrofa; tissue oxygen tension; Ultrasonic investigative techniques
• ISSN: 0022-4804; 1095-8673
• DOI: 10.1016/j.jss.2008.11.002

Background Untreated hypovolemia results in impaired outcome. This study tests our hypothesis whether general hemodynamic parameters detect acute blood loss earlier than monitoring parameters of regional tissue beds. Materials and Methods Eight pigs (23–25 kg) were anesthetized and mechanically ventilated. A pulmonary artery catheter and an arterial catheter were inserted. Tissue oxygen tension was measured with Clark-type electrodes in the jejunal and colonic wall, in the liver, and subcutaneously. Jejunal microcirculation was assessed by laser Doppler flowmetry (LDF). Intravascular volume was optimized using difference in pulse pressure (dPP) to keep dPP below 13%. Sixty minutes after preparation, baseline measurements were taken. At first, 5% of total blood volume was withdrawn, followed by another 5% increment, and then in 10% increments until death. Results After withdrawal of 5% of estimated blood volume, dPP increased from 6.1% ± 3.0% to 20.8% ± 2.7% ( P < 0.01). Mean arterial pressure (MAP), mean pulmonary artery pressure (PAP) and pulmonary artery occlusion pressure (PAOP) decreased with a blood loss of 10% ( P < 0.01). Cardiac output (CO) changed after a blood loss of 20% ( P < 0.05). Tissue oxygen tension in central organs, and blood flow in the jejunal muscularis decreased ( P < 0.05) after a blood loss of 20%. Tissue oxygen tension in the skin, and jejunal mucosa blood flow decreased ( P < 0.05) after a blood loss of 40% and 50%, respectively. Conclusions In this hemorrhagic pig model systemic hemodynamic parameters were more sensitive to detect acute hypovolemia than tissue oxygen tension measurements or jejunal LDF measurements. Acute blood loss was detected first by dPP.