THE SPECIFIC FEATURES OF CELL DEATH OF CIRCULATING NEUTROPHILS IN A SETTING OF EXPERIMENTALLY INDUCED CRUSH SYNDROME.

Although the overall incidence of trauma-induced crush syndrome (CS) is as low as 0.1 per 10,000 of population, which makes it one of the least common traumatic injuries, the hazard of CS lies in the high incidence of hemodynamic and metabolic complications, which call for an early diagnosis of this syndrome. This paper reports the specific features of cell death of neutrophils in rat blood as they changed with time using the model of endogenous toxemia formed in a setting of crush syndrome. To assess apoptosis/necrosis in neutrophils ANNEXIN V FITC assay kit (manufactured by Beckmann Coulter, USA) was used. The results obtained in this study suggest an increase in apoptotic and necrotic processes in a setting of CS from the first day of the experiment through the end of observation. Also we have found a significant impact of reactive oxygen species generation on neutrophils death in a setting of CS. However, other mechanisms to launch apoptosis/necrosis in case of experimental crush syndrome should not be neglected.

Evaluation of Acute Kidney Injury Using Contrast Ultrasonography in a Rabbit Model of Crush Syndrome.

This study aimed to investigate the feasibility of evaluating acute kidney injury (AKI) using contrast ultrasonography in a rabbit model of crush syndrome. Sixty-four New Zealand white rabbits were anesthetized and the left hind limb was wrapped and compressed for 4 h with a sphygmomanometer. Contrast ultrasonography of the left kidney using microbubbles as the contrast medium was performed. The serum levels of blood urea nitrogen (BUN), creatine (Cr), creatine kinase (CK) and lactate dehydrogenase (LDH) were significantly increased in comparison to before the compression. Correlation analysis showed that peak intensity was negatively correlated with the biochemical parameters and area under the curve (AUC) was positively correlated with these parameters. Contrast ultrasonography is thus sensitive to the changes in renal perfusion after limb crush injury in rabbits. The ultrasonography results correlated well with the biochemical parameters that are related to muscle injury and AKI.

A historical perspective on crush syndrome: the clinical application of its pathogenesis, established by the study of wartime crush injuries.

Crush syndrome is a fine example of how pathology can play a direct role in revealing the best treatment and management for diseases. It can occur when crush injuries are sustained. Skeletal muscle becomes damaged under the weight of a heavy object, and victims experience severe shock and renal failure. The discovery of the pathology of crush syndrome belongs to two individuals: Seigo Minami and Eric Bywaters. They separately helped to define the pathogenesis of crush syndrome during World Wars I and II. Seigo Minami is believed to have been the first to record the pathogenesis of crush syndrome. In 1923, he described the cases of three soldiers who died of renal failure caused by crush injury during World War I. Using microscopic studies to investigate the pathology of their kidneys, he found the soldiers had died due to 'autointoxication' caused by rhabdomyolysis. This discovery was not known to Eric Bywaters, who described crush syndrome in 1941, having studied victims of the London Blitz during World War II. He defined the 'autointoxication' as the release of rhabdomyolysis products via reperfusion. He therefore established the need for emergency fluid replacement to treat crush syndrome. The findings made by Minami and Bywaters highlight a remarkable achievement in clinical pathology, despite the adversity of war. It is these findings on which current guidelines are based. By reviewing their work, it is hoped that the role of pathology can be better appreciated as a valuable resource for delineating the treatment and management of diseases.

The reno-protective effects of atorvastatin in crush syndrome and rhabdomyolysis:is there a dilemma?

Background/aim: We aim to determine the effects of low-dose atorvastatin treatment together with crush fluid resuscitation on renal functions and muscle enzyme levels in a rat model of crush syndrome. Materials and methods: The study involved female Wistar Albino rats weighing 250-300 g that were housed with free access to food and water. The crush model was obtained by compression. Rats were randomly divided into four groups: control (C) group, atorvastatin + crush fluid (ACF) group, crush fluid (CF) group, and hypertonic saline (%3) + mannitol + sodium bicarbonate (SM) group. Blood was obtained at 24, 48, and 72 h, and serum creatinine kinase, myoglobin, urea, creatinine, and lactate dehydrogenase levels were studied.Results: All parameters were statistically significantly higher in the control group than in the treatment groups at all hours. However, there was no statistically significant difference among treatment groups regarding any of the parameters.Conclusion: This is the first study determining the role of atorvastatin in the treatment of renal ischemia/reperfusion injury in a crush syndrome and rhabdomyolysis model setting. Larger studies with different atorvastatin doses are required to define the role of this drug in the treatment of renal ischemia/reperfusion injury during crush syndrome.

Combined administration of anisodamine and neostigmine rescued acute lethal crush syndrome through α7nAChR-dependent JAK2-STAT3 signaling.

Previously we showed that Ani (anisodamine)/Neo (neostigmine) combination produced anti-shock effect via activating α7 nicotinic acetylcholine receptor (α7nAChR). In this study, we aim to investigate the therapeutic effect and underlying mechanisms of Ani/Neo combination in acute lethal crush syndrome (CS). In rat and rabbit CS models, Ani/Neo combination increased the 24 h survival rates, improved hemodynamics and decreased the levels of creatine kinase, MB isoenzyme of creatine kinase, blood urea nitrogen, creatinine, K+ in serum. It also decreased the levels of H2O2, myeloperoxidase (MPO) and nitric oxide (NO) in serum and compressed muscle in rat CS model. In wild-type (WT) mice with CS, Ani/Neo combination increased 24 h survival rate and decreased the levels of H2O2, MPO, NO, TNFα, IL-6 and IL-10 in compressed muscle. These effects were attenuated by α7nAChR knockout (KO). Moreover, Ani/Neo combination prevented the decrease of phosphorylation of Janus kinase 2 (JAK2) and phosphorylation of signal transducer and activator of transcription 3 (STAT3) induced by CS. These effects of Ani/Neo in CS mice were cancelled by methyllycaconitine (α7nAChR antagonist) and α7nAChR KO. Collectively, our results demonstrate that Ani/Neo combination could produce therapeutic effects in CS. The underlying mechanism involves the activation of α7nAChR-dependent JAK2-STAT3 signaling pathway.

Prevention of Crush Syndrome through Aggressive Early Resuscitation: Clinical Case in a Buried Worker.

UNLABELLED: Introduction Crush syndrome, of which little is known, occurs as a result of compression injury to the muscles. This syndrome is characterized by systemic manifestations such as acute kidney injury (AKI), hypovolemic shock, and hydroelectrolytic variations. This pathology presents high morbidity and mortality if not managed aggressively by prehospital care. Clinical Case A 40-year-old worker was rescued after being buried underground in a ditch for 19 hours. The patient was administered early resuscitation with isotonic solutions and monitored during the entire rescue operation. Despite having increased plasma levels of total creatine kinase (CK), the patient did not develop AKI or hydroelectrolytic variations. CONCLUSION: Aggressive early management with isotonic solutions before hospital arrival is an effective option for nephron-protection and prevention of crush syndrome. Mardones A , Arellano P , Rojas C , Gutierrez R , Oliver N , Borgna V . Prevention of crush syndrome through aggressive early resuscitation: clinical case in a buried worker. Prehosp Disaster Med. 2016;31(3):340-342.

Double Crush Syndrome.

Double crush syndrome is a distinct compression at two or more locations along the course of a peripheral nerve that can coexist and synergistically increase symptom intensity. In addition, dissatisfaction after treatment at one site may be the result of persistent pathology at another site along a peripheral nerve. Double crush syndrome is a controversial diagnosis; some scientists and surgeons believe it is an illness construction that may do more harm than good because it emphasizes an objective pathophysiologic explanation for unexplained symptoms, disability, and dissatisfaction that may be more psychosocially mediated. However, peripheral neuropathy may coexist with compressive neuropathy and contribute to suboptimal outcomes following nerve decompression. To better manage patients' expectations, treating practitioners should be aware of the possibility of concomitant cervical radiculopathy and carpal tunnel syndrome, as well as the presence of underlying systemic neuropathy.

Immediate Lower Extremity Tourniquet Application to Delay Onset of Reperfusion Injury after Prolonged Crush Injury.

Reperfusion after severe crush injury is an infrequent, but life-threatening condition. It is a unique aspect of prehospital medicine that occurs in the presence of emergency responders attempting to extricate and treat patients who have suffered a crushing injury. These events are unlikely to occur in the hospital setting and, as a result, remain poorly studied. Some evidence exists regarding prophylaxis, but the efficacy of these treatments has not been clearly established. The use of commercial tourniquets to delay the onset of reperfusion injury has previously been described in theory. Extensive literature now exists supporting the safety of tourniquet use in limb trauma and this potential life-saving measure requires further study in patients with crush injury. We present a case of prehospital tourniquet application to delay reperfusion injury after crush injury that resulted in a reduction in morbidity and complete limb salvage.

Disaster nephrology: crush injury and beyond.

Disasters result in a substantial number of renal challenges, either by the creation of crush injury in victims trapped in collapsed buildings or by the destruction of existing dialysis facilities, leaving chronic dialysis patients without access to their dialysis units, medications, or medical care. Over the past two decades, lessons have been learned from the response to a number of major natural disasters that have impacted significantly on crush-related acute kidney injury and chronic dialysis patients. In this paper we review the pathophysiology and treatment of the crush syndrome, as summarized in recent clinical recommendations for the management of crush syndrome. The importance of early fluid resuscitation in preventing acute kidney injury is stressed, logistic difficulties in disaster conditions are described, and the need for an implementation of a renal disaster relief preparedness program is underlined. The role of the Renal Disaster Relief Task Force in providing emergency disaster relief and the logistical support required is outlined. In addition, the importance of detailed education of chronic dialysis patients and renal unit staff in the advance planning for such disasters and the impact of displacement by disasters of chronic dialysis patients are discussed.

Electrocardiographic changes after injury in a rat model of combined crush injury.

BACKGROUND: Crush injury from debris, combined with hypoxia and water and food deprivation (combined crush injury), is common in industrial accidents and events such as earthquakes and terrorist attacks. Whether electrocardiographic changes are associated with combined crush injury is unclear. METHODS: Thirty-six rats underwent electrocardiography at baseline then were randomly assigned to 6 groups of 6. Bilateral hind limbs of all rats were compressed with custom-made clips (pressure 4.5 ± 0.3 kg), and the rats were put into a hypoxic compartment (oxygen concentration 10% ± 0.1%) for 72 hours without food or water. After 72 hours, the rats were moved to a normoxic environment, where the clips were removed (decompression) and food and water were freely accessible. Electrocardiography was performed in a different group at each of days 0, 1, 3, 7, 14, and 28 after decompression. RESULTS: One rat died at 0.6 days. Among the remaining 35 rats, 28 (80%) had abnormal electrocardiographic changes: ST-segment depression (n = 25), tall-peaked T waves (n = 16), arrhythmias (n = 4), abnormal Q waves (n = 2), wide QRS complexes (n = 2) and QT prolongation (n = 1). The abnormality rates among assessed rats were 100% on days 0, 1, and 3; 83% on day 7; and 50% on days 14 and 28. CONCLUSIONS: The findings suggest that abnormal electrocardiographic changes were seen in rats after simulated combined crush injury and decompression and were slow to resolve.

Acute lethal crush-injured rats can be successfully rescued by a single injection of high-dose dexamethasone through a pathway involving PI3K-Akt-eNOS signaling.

BACKGROUND: Crush syndrome (CS) is characterized by ischemia/reperfusion-induced rhabdomyolysis and the subsequent onset of systemic inflammation. CS is associated with a high mortality, even when patients are treated with conventional therapy. We hypothesized that treatment of lethal CS rat model with dexamethasone (DEX) have therapeutic effects on the laboratory findings and clinical course and outcome. METHODS: To create a CS model, anesthetized rats were subjected to bilateral hind limb compression with rubber tourniquets for 5 hours and randomly divided into three groups as follows: saline-treated CS group, CS groups treated with low (0.1 mg/kg) and high doses (5.0 mg/kg) of DEX. Saline for the CS group or DEX for the DEX-treated CS groups was intravenously administered immediately before reperfusion. Under continuous monitoring and recording of arterial blood pressures, blood and tissue samples were collected for histologic and biochemical analysis at designated period before and after reperfusion. RESULTS: Ischemic compression of rat hind limbs reduced the nitrite content in the crushed muscle, and the subsequent reperfusion induced reactive oxygen species-mediated circulatory collapse and systemic inflammation, finally resulting in a mortality rate of 76% by 48 hours after reperfusion. A single injection of high-dose DEX immediately before reperfusion activated endothelial nitric oxide synthase (eNOS) by sequential phosphorylation through the nongenomic phosphoinositide 3-kinase (PI3K)-Akt-eNOS signaling pathway. DEX also exhibited anti-inflammatory effects by modulating proinflammatory and anti-inflammatory mediators, consequently suppressing myeloperoxidase activities and subsequent systemic inflammation, showing a complete recovery of the rats from lethal CS. CONCLUSION: These results indicate that high-dose DEX reduces systemic inflammation and contributes to the improved survival rate in a rat CS model.

Contrast-enhanced ultrasound assessment of muscle blood perfusion of extremities that underwent crush injury: an animal experiment.

BACKGROUND: This research aimed to study the assessment of local muscle microcirculation perfusion of extremities that underwent crush injuries by using contrast-enhanced ultrasonography (CEUS). METHODS: A total of 28 New Zealand rabbits were anesthetized by using intramuscular pentobarbital sodium (30 mg/kg). A balloon cuff device was used to create crush injuries to the left hind leg of each rabbit with a force of 18.6 kPa. CEUS was performed at the 0.5th, 2nd, 6th,24th, and 72nd hour after the release of the crush pressure. Peak intensity (PI) of the crushed regions was compared with those of the uncrushed regions and before the creation of crush injury. Receiver operating characteristic analysis was used to determine the diagnostic value of PI for the crushed region. RESULTS: During the 72nd hour after the release of the crush pressure, 5 of the 28 rabbits died, and thus, their statistics were eliminated from the experiment. At different time points after the release of the crush pressure, the crushed regions in all 23 survivals showed quick and high enhancement, and their intensities were higher than those of the un crushed region in the arterial phase. The time-intensity curves of the crushed regions all appeared as rapid lift-gradual drop. PIs were obviously higher in the crushed regions than in the uncrushed regions and than those before the creation of crush injury ( p G 0.001). Receiver operating characteristic curves showed that extremity crush injury was diagnosed by using PI value. CONCLUSION: CEUS presents that the microcirculation perfusion of the crushed muscle increased obviously after the release of the crush pressure.PIs evaluated quantitatively the microcirculation perfusion changes. It may suggest a potential alternative for evaluating microcirculation abnormality of the muscle crush injury to the extremities.

[Experimental study on establishment of a simple model of rats crush injury-crush syndrome].

OBJECTIVE: To establish a repeatable, simple, and effective model of rat crush injury and crush syndrome. METHODS: A total of 42 female Sprague Dawley rats (2-month-old, (CS) so as to lay a foundation for further study on CS. weighing 160-180 g) were divided randomly into the control group (n=6) and experimental group (n=36). The rats of the experimental group were used to establish the crush injury and CS model in both lower limbs by self-made crush injury mould. The survival rate and hematuria rate were observed after decompression. The biochemical indexes of blood were measured at 2, 4, 8, 12, 24, and 48 hours after decompression. The samples of muscle, kidney, and heart were harvested for morphological observation. There was no treatment in the control group, and the same tests were performed. RESULTS: Seven rats died and 15 rats had hematuria during compression in the experimental group. Swelling of the lower limb and muscle tissue was observed in the survival rats after reperfusion. The liver function test results showed that the levels of alanine transaminase and aspartate aminotransferase in the experimental group were significantly higher than those in the control group (P < 0.05). The renal function test results showed that blood urea nitrogen level increased significantly after 2 hours of decompression in the experimental group, showing significant difference when compared with that in the control group at 12, 24, and 48 hours after decompression (P < 0.05); the creatinine level of the experimental group was higher than that of the control group at 4, 8, 12, and 24 hours, showing significant difference at 8, 12, and 24 hours (P < 0.05). The serum K+ concentration of the experimental group was higher than that of the control group at all time, showing significant difference at the other time (P < 0.05) except at 2 hours. The creatine kinase level showed an increasing tendency in the experimental group, showing significant difference when compared with the level of the control group at 4, 8, 12, and 24 hours (P < 0.05). The histological examination of the experimental group showed that obvious edema and necrosis of the muscle were observed at different time points; glomeruli congestion and swelling, renal tubular epithelial cell degeneration, edema, necrosis, and myoglobin tube type were found in the kidneys; and myocardial structure had no obvious changes. CONCLUSION: The method of the crush injury and CS model by self-made crush injury mould is a simple and effective procedure and the experimental result is stable. It is a simple method to establish an effective model of rats crush injury and CS.

Impact of traumatic muscle crush injury as a cause of cardiomyocyte-specific injury: an experimental study.

BACKGROUND: Muscle crush injury commonly occurs after earthquakes, collapse of buildings and sjambok beatings, and it often induces crush syndrome if not treated promptly. The general manifestation of crush syndrome is the presence of myoglobinuria with acute renal failure. However, whether cardiomyocyte injury is induced after muscle crush injury has not been investigated. The aim of this study was to observe the effects of muscle crush injury on cardiomyocyte injury and its relationship to the changes of ANP and ET-1 levels after muscle crush injury in rats. METHODS: Muscle crush injury was produced in Male Sprague-Dawley rats. Forty-eight rats were divided into six groups. The changes of electrocardiogram (ECG) were recorded. The serum levels of K(+), Ca(2+), urea, creatinine (CR), creatine kinase (CK), creatine kinase-myocardial band (CK-MB) and cardiac troponin I (cTnI) were detected by automated biochemical analysis and automated chemiluminescence assay, respectively. The myocardial and plasma levels of ANP and ET-1 were investigated by radioimmunoassay. Myocardial apoptosis and caspase-3 protein expression were quantitatively analysed by TUNEL-staining and Western blotting, respectively. RESULTS: After six hours of decompression, the serum levels of K(+) and urea increased and ST-segment elevated and heart rates decreased pronouncedly over 48h, CR increased and Ca(2+) decreased considerably over 24h. The serum levels of CK-MB and cTnI increased significantly from 6h to 24h and CK increased markedly from 0h to 24h after decompression and then decreased slowly. However, after 48h of decompression, the serum levels of cTnI were still higher than those of the control group. Plasma levels of ANP and ET-1 increased and myocardial ANP and ET-1 decreased progressively over 48h, and changed significantly from 6h to 48h after decompression. The number of TUNEL-positive myocytes and caspase-3 protein expression were higher from 6h to 48h after decompression. Moreover, the levels of K(+), urea, CR, CK, CK-MB, cTnI and caspase-3 reached their highest values after 12h of decompression. There were significant correlations between the plasma ANP elevation and the myocardial ANP decline, between the plasma ANP elevation and the plasma ET-1 increase, and between the plasma ET-1 increase and the myocardial ET-1 decline. CONCLUSIONS: Cardiomyocyte injury was induced by muscle crush injury at the early stage of decompression but not at compression. The most dangerous period of cardiomyocyte injury was at the 12th hour of decompression. Cardiomyocyte injury may partly relate to the changes of ANP and ET-1.

Muscle crush injury of extremity: quantitative elastography with supersonic shear imaging.

The aim of this study was to determine the characteristic of muscle crush injury at quantitative ultrasonographic elastography using supersonic shear imaging (SSI). Twenty-three New Zealand rabbits underwent crush injury to left hind leg caused by a special balloon cuff device. Conventional ultrasonography and SSI quantitative elastography were performed at both crushed and uncrushed regions of the left hind legs. Quantitative lesion elasticity was measured using the Young's modulus (in kilopascals) at 0.5 h, 2 h, 6 h, 24 h and 72 h after the release of the crushing pressure. Compared with those from the uncrushed regions, both the maximum and mean elasticity values at these time points from the crushed regions were significantly higher (p < 0.001). A receiver operating characteristic (ROC) analysis was employed to assess diagnostic performance. ROC curves showed that extremity crush injury was diagnosed using elasticity value and the greater the elasticity value, the greater the diagnostic value. SSI provides quantitative elasticity measurements, thus, adding complementary information that potentially could help in crush injury characterization with conventional ultrasonography.

Clinical characteristics and electrodiagnostic features in patients with carpal tunnel syndrome, double crush syndrome, and cervical radiculopathy.

Similar unilateral neck and upper limb symptoms are often due to various entrapment neuropathies; carpal tunnel syndrome (CTS) and cervical radiculopathy (CR) are common causes among them. Therefore, we investigated the clinical characteristics and electrodiagnostic features of patients with carpal tunnel syndrome, cervical radiculopathy, and both conditions, called double crush syndrome (DCS). The medical records and electrodiagnostic reports of 866 patients with suspected CTS and CR visited a tertiary-care hospital were retrospectively analyzed. After excluding 101 patients with confounding conditions, 151 (20%) patients were diagnosed to have sole cases of CTS; 362 (47%) patients were diagnosed to have sole cases of CR; 198 (26%) patients were diagnosed to have DCS, while 54 (7%) patients had mere symptoms. Sole cases of CR had the highest incidences of neck pain, upper back pain, wrist and hand weakness. Female patients had the highest incidences of all the diseases in their sixth decade. Male patients had comparably distinguished high occurrence of all the diseases in their fifth to sixth decades. Although comparison of nerve conduction studies between patients with mere symptoms and patients with sole cases of CTS or DCS showed statistical differences, comparison between the latter two revealed no difference. We found most patients referred for electrodiagnostic studies had cervical radiculopathy. High concomitant occurrence of CTS and CR suggests cautious evaluation of patients with upper limb symptoms is important, because the management of these conditions is quite different.

[Hepatoprotective properties of cytochrome C in traumatic toxicosis].

Experiments on rats showed that traumatic toxicosis (crush syndrome) was accompanied by disorders of both excretion and detoxication functions of the liver and a decrease in the energy potential of the liver. Systemic administration of cytochrome C (10 mg/kg) immediately after trauma and decompression increased the level of endogenous cytochrome C, recovered the pool of adenine nucleotides, normalized bromsulfaleine excretion from the blood, and decreased the content of toxic metabolites in the blood. The obtained experimental data show that cytochrome C possesses high hepatoprotective properties with respect to the development of traumatic toxicosis.

The influence of hypothalamic cytokine PRP on protein synthesis in brain subcellular compartments in crush syndrome.

Crush-syndrom (CS) was characterized by Bywaters E.G.L. in 1941 after London blitz. The soft tissues is followed by acute hemodynamic shock, myoglobinuria, acute renal insufficiency, and lethal endotoxicity. Data of CS pathogenesis study has shown that the largest changes in Crush occur during decompression and are accompanied by acute alteration of brain protein synthesis and strong morphological changes of brain structures. The period of decompression might be characterized by the proteolytic breakdown of the myoglobine and formation of toxic peptides. In our current work we have identified four newly formed peptides in the brain of the animals subjected to the experimental muscle tissue injury. Our investigations related with the CS experimental model have demonstrated that during the 2-hours compression protein synthesis was decreased in cytosol (32,7%) and mitochondria (49%), after 5-h compression there were registered non-significant changes in the level of protein synthesis. Intraperitoneal administration of Proline-rich peptide, ((PRP), 1 mcg/100g weight of rats), originating from proteolysis of C-terminal glycoprotein a neurophysin II along with vasopressin and oxytocin and transferring from the hypothalamus to the neurohypophysis by axonal transport, initiates activation of the protein synthesis in all studied cellular subcomponents of brain cells. The positive effect of the peptide is conditioned, most probably, by activation of the immune system and adaptation mechanisms, including mobilization of endogen-protective mechanisms of the organism.