Effects of perfluorocarbon emulsions on microvascular blood flow and oxygen transport in a model of severe arterial gas embolism.
BACKGROUND
Arterial gas embolism (AGE) is a clinical problem that occurs directly in cardiopulmonary bypass machines in open-heart surgeries, or indirectly (through cardiac or pulmonary right to left shunts) in dive accidents, resulting in serious morbidity and even death. Perfluorocarbon (PFC) emulsions have been used for the treatment of AGE in an animal model. We hypothesized that PFC emulsions enhance microvascular blood flow, speed bubble resolution, and oxygenation in AGE compared with saline in a model of cremaster muscle from anesthetized rats.


METHODS
AGE was induced by direct air injection into the femoral artery ipsilateral to the studied cremaster muscle. Microhemodynamics, microvascular, and tissue oxygenation were determined before and after treatment with two different commercial PFC emulsions (C10F20, Oxycyte; Oxygen Biotherapeutics, Inc and C10F18, PHER-O2; Sanguine Corporation, Inc) compared with saline in real time using brightfield and phosphorescence microscopy.


RESULTS
Blood pressure and heart rate remained unchanged. Systemic PO2, oxygen (O2) content, and glucose were higher in PFC groups, whereas hematocrit dropped in all groups. Arteriolar blood flow went up 85% and 80% of baseline after C10F20 and C10F18 treatments, respectively, versus 11% after saline treatment. Arteriolar and tissue PO2, and O2 delivery were higher in PFC groups compared with the control group. There was an increase in arteriolar blood flow, reduction in diffusional resistance of O2 in the plasma, and improved tissue oxygenation.


CONCLUSIONS
Administration of PFC emulsions in AGE is superior to saline primarily because of surfactant properties along with air bubble reabsorption.
Department of Anesthesiology, Virginia Commonwealth University Reanimation Engineering Shock Center (VCURES), Virginia Commonwealth University, Richmond, Virginia; U.S. Army Institute of Surgical Research, Damage Control Resuscitation, San Antonio, Texas. Electronic address: lntorres0624@yahoo.com.
Luciana N
LN
Torres
Department of Anesthesiology, Virginia Commonwealth University Reanimation Engineering Shock Center (VCURES), Virginia Commonwealth University, Richmond, Virginia; Department of Emergency Medicine, Virginia Commonwealth University Reanimation Engineering Shock Center (VCURES), Virginia Commonwealth University, Richmond, Virginia.
Bruce D
BD
Spiess
U.S. Army Institute of Surgical Research, Damage Control Resuscitation, San Antonio, Texas; Department of Emergency Medicine, Virginia Commonwealth University Reanimation Engineering Shock Center (VCURES), Virginia Commonwealth University, Richmond, Virginia.
Ivo P
IP
Torres Filho
D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D004618:Embolism, Air / Q000188:drug therapy* / Q000503:physiopathology; D005263:Femoral Artery / Q000503:physiopathology; D005466:Fluorocarbons / Q000494:pharmacology*; D006339:Heart Rate / Q000502:physiology; D006400:Hematocrit; D006454:Hemoglobins; D008297:Male; D008833:Microcirculation / Q000187:drug effects*; D010100:Oxygen / Q000097:blood*; D010313:Partial Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D012039:Regional Blood Flow / Q000187:drug effects*; D012720:Severity of Illness Index; D013501:Surface-Active Agents
D005466:Fluorocarbons; D006454:Hemoglobins; D013501:Surface-Active Agents; D010100:Oxygen
Intravital microscopy; Oxygen delivery; Oxygen transport; Phosphorescence quenching; Surfactant