Objective: To perform a reproducible long-term (10 days) large animal model of multiple systems organ failure without necessity of a continuous stimulus.

Animal studies have shown that 21-aminosteroids have beneficial effects on cell and organ functions in several acute models of traumatic, hemorrhagic, and septic shock. However, it is not known if the 21-aminosteroid U74389G has any beneficial effect on organ functions in a recently developed chronic sheep model of multiple organ dysfunction after trauma. Furthermore, it is not known whether this drug has any effect on in vivo leukocyte function in this animal model. To study this, anesthetized animals were subjected to hemorrhagic shock (2 hr at a mean arterial blood pressure of 50 mmHg) and femoral reaming at Day 0. The following 5 days, endotoxin (ET; 0.75 micrograms/kg BW) and zymosan-activated plasma (ZAP; 20 ml/animal) were given every 12 hr. During the third phase (Days 6-10), the animals were merely observed. This kind of model resulted in progressive organ dysfunction indicated by increased cardiac output, decreased systemic vascular resistance, an increase of plasma-sorbitoldehydrogenase, impaired bilirubin metabolism, and impaired renal and lung function in nontreated animals. Animals receiving U74389G (3 mg/kg BW) during resuscitation from hemorrhagic shock and each time before ET/ZAP administration showed less severe organ dysfunction. Furthermore, U74389G showed beneficial effects on lung function, although it had no effect on accumulation of leukocytes in the lung or on the chemiluminescence response of isolated leukocytes from bronchoalveolar lavage fluid. These results suggest that U74389G may be a useful therapeutic agent in the prevention of multiple organ dysfunction after hemorrhagic and traumatic shock.

Trauma-induced multiple organ failure in sheep was prevented by aprotinin therapy. Multiple organ failure was induced in 16 female merino sheep by initial haemorrhagic shock and intramedullary femoral nailing (day 0), and 12 hourly injections of 0.75 micrograms/kg Escherichia coli endotoxin +0.7 ml/kg zymosan-activated plasma (days 1-5). In addition, the aprotinin group (n = 6) received simultaneous injections of 5 mg/kg (35 695 KIU/kg) aprotinin, whereas ten animals did not receive aprotinin and served as the control group (n = 10). Organ functions were monitored for a total of 11 days by measuring haemodynamic, cardio-respiratory and biochemical quantities of blood, urine and epithelial lining fluid. During the subsequent eleven day period, aprotinin induced a significant (p < 0.05) reduction of the pathological changes (development of multiple organ failure) seen in the control group. Thus, aprotinin prevented an alteration of cardiac function (cardiac index for control/aprotinin groups at day 1: 6.5/6.2, and at day 10: 10.47/7.0 1/min x m2), an impairment of lung function (mean pulmonary arterial pressure at day 1: 2.26/1.86, and at day 10: 3.83/2.13 kPa; epithelial lining fluid/plasma ratio of albumin concentrations as a direct marker of lung capillary permeability damage at day 0: 0.18/0.16, and at day 10: 0.45/0.15), a deterioration of liver function (plasma sorbitol dehydrogenase at day 0: 7.9/7.6, and at day 10: 29.6/7.4 U/1), but not of renal function (creatinine clearance at day 1: 91.4/66.1, and at day 10: 53.1/59.2 ml/min). Urinary aprotinin excretion increased up to day 3, then decreased rapidly despite further aprotinin administration. As a non-specific marker of cell damage, plasma lactate dehydrogenase indicated an aprotinin-induced organ protection (day 0: 501/409, and at day 10: 719/329 U/1). The neutrophil count and the measured chemiluminescence of neutrophils from the blood and epithelial lining fluid showed that aprotinin reduced the in vivo neutrophil activation, the alveolar neutrophil invasion, the production of inflammatory mediators, and the production of reactive oxygen metabolites during the passage of the capillary-interstitial-alveolar space by neutrophils.

The trauma-induced activation of neutrophils and their functional alterations, i.e., increase in adherence and release of oxygen derived metabolites, is considered to play a central role in the initiation and amplification of capillary endothelial cell damage and following organ failure. In the present study neutrophil-endothelial cell interaction was studied using an in vitro model of human umbilical cord vein endothelial cells and human neutrophils. Production of oxygen-derived metabolites was determined by comparing mean peak chemiluminescence of neutrophils from multiply traumatized patients (n = 40) and mean peak chemiluminescence of neutrophils from blood donors (n = 160). Adherence and endothelial injury by neutrophils of multiply traumatized patients were compared with data of healthy blood donors. Chemiluminescence response of 70,000 neutrophils isolated from healthy control individuals was 699 +/- 98 x 10(3) cpm and could be increased significantly by endothelial cells to 1410 +/- 135 x 10(3) cpm (p < 0.05). Chemiluminescence response to neutrophils of polytraumatized patients was 1174 +/- 94 x 10(3) cpm and could not be significantly increased by endothelial cells (1419 +/- 120 x 10(3) cpm). Adherence of neutrophils of blood donors to endothelial cells was 12.31 +/- 0.77%. Adherence of neutrophils of polytraumatized patients was significantly increased to values of 24.83 +/- 2.03%. Injury of endothelial cells was not detectable with neutrophils from blood donors (1.11 +/- 1.09% 111in-release). Significantly increased 111in-release was apparent upon incubation with neutrophils of polytraumatized patients (5.76 +/- 1.28%). The data shows evidence of in vivo preactivation of neutrophils of polytraumatized patients, and supports the hypothesis that endothelial cells play an active role in neutrophil-endothelial cell interactions by modulating production of oxygen-derived metabolites.

Remmers, D.; Dwenger, A.; Pape, H.-C.; Grotz, M.; Gruner, A.; Scharf, H.; Regel, G. Author Information

Severe head trauma (BI) associated with long bone fractures is present in about 60% of polytraumatized patients admitted to hospital. However, there is no consensus regarding early fracture stabilization in such patients. In an experimental sheep study, the influence of intramedullary nailing of the femur (IMNF) on a cold-induced, vasogenic brain edema (method of Klatzo) in combination with traumatic hemorrhagic shock (THS) was investigated. Three animal groups (n=6) were explored: group A, only BI; group B, BI and THS; group C, BI, THS and IMNF. The animals remained intubated, on controlled ventilation, sedated and received analgesia during the whole experiment. For a period of 6 h after the cold-induced brain injury the hemodynamic changes were measured and the intracranial pressure (ICP) was recorded in the left and the right hemisphere continuously. The hemorrhagic shock (MAP = 60 mm Hg) was maintained over 1.5 h. At the end of the reperfusion period (2 h) the nailing of the femur was performed. The animals were killed and the percentage water content of the brain was determined and compared with the brain water content of a control group (n = 6). There were no significant differences in ICP between groups A, B and C before or after IMNF, but in group C the ICP increased significantly after nailing. Brain water content in group C was significantly higher than in the control group and slightly significantly higher than in groups A and B. Brain edema and ICP are increased by IMNF. Primary nailing of the femur in patients with severe brain injury should be considered carefully. Alternatively, another technique for stabilization could be used.

Lazaroide sind sehr lipophile 21-Aminosteroide, denen die typischen Nebenwirkungen der Glucokorticoide fehlen. Sie hemmen die radikalinduzierte und eisenkatalysierte Lipidperoxidationsreaktion im postischämischen Gewebe als Sauerstoffradikalfänger und durch membranstabilisierende Eigenschaften. Der mögliche therapeutische Nutzen dieser Substanzen ist bisher nur an Akutmodellen untersucht worden. Wir untersuchten daher die Effekte des Lazaroids U-74389G auf mehrere Organfunktionen in einem chronischen Großtiermodell des multiplen Organversagens am Schaf.

In the past various attempts have been made to develop a standardized animal model of multiple organ failure (MOF). Until now there has been no large animal model, that imitates the clinical situation of multiple trauma patients up to MOF. In a manner similar to the pathophysiological sequence in multiple trauma patients, the combination of damaging mechanisms in the early phase (hemorrhagic shock, operating trauma, application of endotoxin (ET; 0.75 microgram/kg body weight) and zymosan-activated plasma (ZAP; 20 ml) every 12 h on days 1-5) leads to sequential irreversible damage to several organs in the late phase (> day 6) in sheep (n = 10). In this animal model representative organ parameters showed a similar course to that in MOF after multiple trauma in humans. The cardiac index increased significantly in the late phase (day 1: 6.47 +/- 0.41 ml/min x m2; day 10: 10.36 +/- 0.79 ml/min x m2), arterial oxygen pressure declined significantly (day 1: 103.1 +/- 1.6 mmHg; day 10: 89.8 +/- 4.2 mmHg). Liver function was impaired, bilirubin levels showed a significant increase (day 1: 2.94 +/- 0.34 mumol/l; day 10: 7.19 +/- 0.91 mumol/l). Creatinine clearance was low on day 1 (54.3 +/- 7.4 ml/min), increased up to day 5 and deteriorated again significantly in the late phase over the entire period (day 2: 104.3 +/- 26.8 ml/min; day 10: 53.1 +/- 17.6 ml/min).

Severe head trauma (BI) associated with long bone fractures is present in about 60% of polytraumatized patients admitted to hospital. However, there is no consensus regarding early fracture stabilization in such patients. In an experimental sheep study, the influence of intramedullary nailing of the femur (IMNF) on a cold-induced, vasogenic brain edema (method of Klatzo) in combination with traumatic hemorrhagic shock (THS) was investigated. Three animal groups (n = 6) were explored: group A, only BI; group B, BI and THS; group C, BI, THS and IMNF. The animals remained intubated, on controlled ventilation, sedated and received analgesia during the whole experiment. For a period of 6 h after the cold-induced brain injury the hemodynamic changes were measured and the intracranial pressure (ICP) was recorded in the left and the right hemisphere continuously. The hemorrhagic shock (MAP = 60 mm Hg) was maintained over 1.5 h. At the end of the reperfusion period (2 h) the nailing of the femur was performed. The animals were killed and the percentage water content of the brain was determined and compared with the brain water content of a control group (n = 6). There were no significant differences in ICP between groups A, B and C before or after IMNF, but in group C the ICP increased significantly after nailing. Brain water content in group C was significantly higher than in the control group and slightly significantly higher than in groups A and B. Brain edema and ICP are increased by IMNF.(ABSTRACT TRUNCATED AT 250 WORDS)

Remmers, D.; Dwenger, A.; Pape, H. C.; Grotz, M.; Gruner, A.; Scharf, H.; Regel, G. Author Information

Bei in vitro-, tierexperimentellen und klinischen Untersuchungen zu Mechanismen des Neutrophilen (PMN)-assoziierten Organschadens hat sich gezeigt, daß das Abfangen reaktiver Sauerstoff-Metabolite (ROM) oder die Hemmung proinflammatorischer Proteinasen (Kallikrein, Plasmin, Elastase) eine Verminderung oxidativer/entzündlicher Prozesse mit reduziertem Organschaden bewirkt [1–9]. Am Modell des Trauma-induzierten sequentiellen irreversiblen Multiorganversagens (MOV) am Schaf [10] wird untersucht, ob die Therapie mit einer Kombination des untoxischen, extrem hydrophilen und hochwirksamen ROM-Scavengers Ascorbinsäure (ASC) und des Plasmin/Kallikrein-Inhibitors Aprotinin (APR) die oxidativen/entzündlichen Prozesse soweit reduziert, daß die Entwicklung eines (Multi)Organversagens ausbleibt.

The effect of different concentrations (0.8, 4.35, 8.7, 17.5, 25 and 35 mg/mL) of intravenous immunoglobulin G (Endobulin) on neutrophil-endothelial cell interaction was studied using an in vitro model of human umbilical cord vein endothelial cells and human neutrophils. Because adherence of neutrophils to endothelial cells is an essential component in inflammatory processes leading to endothelial cell injury the influence of immunoglobulin G on adherence has been investigated. A second aim of the present study was to determine changes in chemiluminescence response of neutrophils during adherence to endothelial cells. Production of oxygen-derived metabolites, measured by chemiluminescence response of neutrophils, decreased significantly in the presence of 8.7 mg immunoglobulin/mL test during coincubation of neutrophils and endothelial cells (p < 0.025). The adherence of neutrophils to endothelial cells was significantly decreased at a concentration of 8.7 mg immunoglobulin/mL test (p < 0.025). The present results indicate that this preparation of immunoglobulin G might exert a protective effect on neutrophil-endothelial cell interaction by decreasing adherence of neutrophils to endothelial cells and by scavenging reactive oxygen metabolites. metabolites. Therefore, the current investigation points to a probable protective effect of immunoglobulin G in oxidative diseases, such as the adult respiratory distress syndrome.