As the technologic sophistication of generation and distribution of electrical energy has grown, so has the general concern about the effects of electric fields on human health. There can be no doubt that the significance of electrical trauma will continue to grow with our increasing use of power. It is apparent that our understanding of the various forms of electric trauma must increase, while we continue to promote safety near electrical hazards and develop effective medical therapies. Tissue damage as a result of electrical injury occurs by two mechanisms which are summative in action and have a variable degree of contribute to the ultimate damage produced. Thermal tissue damage occurs as a result of heat generated within the tissue (which offer an electrical resistance) secondary to the passage of the electrical current. High temperatures can also lead to cell membrane components, e.g., phospholipids, to dissolve. Electroportation damage is the tissue damage induced secondary to the strong electric field. Transmembrane potentials caused by electrical current result in the formation of pore in the phospholipid component of the cell membrane resulting in loss of function of the cell membrane with consequent cell death.
Animals ; Electric Injuries/physiopathology* ; Heart Injuries/physiopathology* ; Hemodynamics ; Humans ; Muscle, Skeletal/injuries*

OBJECTIVE: To observe the changes of electrocardiogram and serum cardiac troponin I at the early stage of severe crush injury in rats. METHODS: Crush injury was produced in Sprague-Dawley rats. The changes of electrocardiogram were recorded with the standard II, the serum levels of cardiac troponin I were studied by automated chemiluminescence assay. RESULTS: The ST segment elevated considerably after crush injury and lasted 24 h, the levels of serum cTnI were much higher than those of the control groupes after 6 h of injury. CONCLUSION Cardiomyocyte injury was induced in the early phase of crush injury.
Animals ; Crush Syndrome/physiopathology* ; Electrocardiography ; Extremities/injuries* ; Female ; Heart Injuries/physiopathology* ; Male ; Rats ; Rats, Sprague-Dawley ; Troponin I/blood*

OBJECTIVETo investigate therapeutics for and the pathological basis of combined radiation and burn injuries.

METHODSCombined radiation and burn injuries on mice and rats were inflicted by gamma ray irradiation from a (60)Co source and thermal radiation from a 5 kW bromotungsten lamp.

RESULTSThe dysfunction of myocardium played an important role in the development of early stage shock. Transfusion of irradiated (in vitro, 20 Gy) or stored (4 degrees C, 7 days) blood after irradiation was done to promote the success of allo-transplantation of bone marrow. Decrease of IL-4 mRNA expression was the molecular basis of depression of intestinal mucosa immune and intervention of IL-4 showed an antagonistic effect on enterogenic infection. A new lipid component extracted from burn eschar was documented for the first time and its toxic effects were elucidated. The survival rate of alloskin grafts after removal of burn eschar from the recipient animals was obviously increased in combined injury due to reduction of immune rejection activity by the radiation effect. In contrast, in animal models with simple burn, the alloskin grafts were all rejected within ten days after the procedure. A successful therapeutic result (survival rate: 92% for 30 days and 67% for 100 days) was obtained by comprehensive management of treated animals, while the untreated control animals all died within 3 - 7 days after injury.

CONCLUSIONThe pathogenesis of injury caused by simultaneous radiation and burn is extremely complicated and the treatment is very difficult. A comprehensive management program consisting of several therapeutic measures aimed at key links of the pathogenesis may achieve significantly improved results.

Animals ; Burns ; pathology ; physiopathology ; therapy ; Calcium ; metabolism ; Heart ; physiopathology ; Hematopoiesis ; Mice ; Radiation Injuries ; pathology ; physiopathology ; therapy ; Rats ; Rats, Wistar

OBJECTIVE: To observe the changes of cardiac functional indicators in spontaneously hypertension rats (SHR) suffered by struck injuries of soft tissues, form which to discuss the significance in relationship between injury and disease. METHODS: SHRs were divided into four groups according to the degree, and whose thigh was struck with the homemade hit instrument. Then the blood pressure, heart rate as well as serum biochemical indicators (CK, CK-Mb, LDH, Cr, BUN, HBDH and AST) were examined. In addition, the morphological changes of heart, brain and kidney were also observed. RESULTS: The observe values of heart rate and blood pressure of SHRs seemed have relation to the degree of damage, but there were no statistically significance between different hit degree groups. In terms of serum biochemical indicators, all seven indicators of the hit group had significant difference with that of the control group, and the AST CK, CK-MB levels were difference between the group of different strike degree. CONCLUSIONS Struck injuries of soft tissues can result in forepart damage of cardiac muscle. The biochemical indicators reflect the degree of injury, and they could be used as a type of objective enzymology indicators for analysis of the relationship between injury and disease in forensic practice.
Animals ; Aspartate Aminotransferases/blood* ; Biomarkers/blood* ; Blood Pressure ; Creatine Kinase/blood* ; Female ; Heart/physiopathology* ; Heart Rate ; Hindlimb/injuries* ; Hypertension/physiopathology* ; Kidney/physiopathology* ; Male ; Myocardium/pathology* ; Random Allocation ; Rats

OBJECTIVECardiac injuries are one of the most challenging injuries in the field of trauma surgery. Their management often requires immediate surgical intervention, excellent surgical technique and the ability to provide excellent postoperative critical care to patients. The aim of this study was to evaluate the outcome and survival rate of patients with penetrating cardiac injury in southern Iran, Shiraz.

METHODSFrom January 2001 to June 2007, medical records of all patients suffering from penetrating cardiac injuries were reviewed and their outcomes were investigated. The inclusion criterion was the presence of a confirmed penetrating cardiac injury intraoperatively or by autopsy. Patients with blunt cardiac injuries were excluded from the study.

RESULTSThe study consisted of 37 patients, including 1 gunshot wound (2.7%), 35 stab wounds (94.6%) and 1 (2.7%) shotgun wound. The overall survival rate was 76% (28 in 37) and that in stab wound patients was 80%. The collected data of 9 expired patients revealed 11% death on arrival, 67% hypotensive, and 22% normotensive considering physiologic presentation. Paired sample test showed significant correlation between mortality and electrocardiographic changes, amount of retained blood in pericardium, clinical stage and physiologic condition at presentation, as well as associated injury type (gunshot more than stab wound).

CONCLUSIONOur results show that injury mechanism and initial cardiac rhythm are significant predictors of outcomes in patients with penetrating cardiac injuries. Besides, gunshot injury and exsanguination are the most important predictive variables of mortality.

Adolescent ; Adult ; Electrocardiography ; Female ; Heart Injuries ; mortality ; physiopathology ; Humans ; Iran ; epidemiology ; Male ; Middle Aged ; Survival Rate ; Wounds, Penetrating ; mortality ; physiopathology

PURPOSETo evaluate the usefulness and information collecting ability of speckle tracking imaging techniques in the assessment of myocardial regional ventricular contractility in a rabbit model with blunt cardiac injury.

METHODSFifteen healthy New Zealand rabbits weighing (2.70 ±0.28) kg were anesthetized (3% pentobarbital sodium/i.v) and impacted using the BIM-II biological impact machine to induce myocardial contusion (MC). Hemodynamic parameters, such as heart rate, systolic pressure, mean arterial pressure, diastolic pressure and central venous pressure, were determined before and after MC. Further, parameters reflecting left ventricular functions, such as left ventricular end systolic pressure, left ventricular end diastolic pressure, isovolumic pressure (IP) and the maximal increasing/decreasing rate of left intraventricular pressure (±dp/dtmax), were also determined before and after MC. Left ventricular functions were determined either by two dimensional transthoracic echocardiography or by speckle tracking imaging for segmental abnormal ventricular wall motions.

RESULTSHeart rate, systolic pressure, diastolic pressure and mean arterial pressure decreased significantly but transiently, while central venous pressure markedly increased after MC. In contrast to significant changes in diastolic functions, there was no significant change in cardiac systolic functions after MC. The speckle tracking imaging demonstrated that strain values of different myocardial segment significantly decreased post impact, and that of the ventricular segment decreased from segment to segment.

CONCLUSIONSpeckle tracking imaging is useful and informative to assess myocardial regional dysfunctions post MC.

Animals ; Echocardiography ; Female ; Heart Injuries ; diagnostic imaging ; physiopathology ; Hemodynamics ; Male ; Myocardial Contraction ; Rabbits ; Ventricular Function ; Wounds, Nonpenetrating ; diagnostic imaging ; physiopathology

OBJECTIVETo study changes and rules of the left ventricular functions in rabbits with myocardial contusion through parallel functional analysis by using echocardiography combined with cardiac catheter intervention.

METHODSThirty healthy rabbits were selected and impacted to make moderate or severe myocardial contusion by BIM-II biomedical impact machine. The changes of hemodynamics and cardiac systolic and diastolic functions were respectively observed before injury and 1, 4, 8 and 24 hours after injury.

RESULTSAfter myocardial contusion, the heart rate, systolic pressure, diastolic pressure and mean arterial pressure of rabbits decreased remarkably at 1-4 hours. The left ventricular end systolic pressure (LVESP), the maximum increasing rate of the left intraventricular pressure (+dp/dtmax), isovolumic pressure (IP) and the maximum systolic velocity of the left ventricle (Vmax) also decreased markedly. And then these parameters recovered to the level of preinjury at 8-24 hours. The left ventricular end-diastolic pressure (LVEDP), the rate of the left intraventricular pressure (-dp/dtmax) and the decreasing time constant of the left intraventricular pressure (T) increased remarkably 1 hour after myocardial contusion, and did not decrease until 8 hours after myocardial contusion. Detection by echocardiography showed that ejection fraction of the left ventricle markedly decreased at 24 hours after myocardial contusion, while the systolic volume decreased obviously as early as 1 hour after myocardial contusion, at 4-8 hours it recovered a little and again decreased at 24 hours. The end systolic volume and end diastolic volume increased after myocardial contusion, but statistical significance was only seen at 8 hours after myocardial contusion.

CONCLUSIONSCardiac functions of the left and right ventricles are markedly injured after myocardial contusion with disorders of the left ventricle diastolic function and of the right ventricle systolic function as the dominant injury. While the systolic function of the left ventricle can recover. Echocardiography shows clinical importance in detection of early injuries of cardiac functions.

Animals ; Contusions ; physiopathology ; Female ; Heart Function Tests ; Heart Injuries ; diagnostic imaging ; physiopathology ; Hemodynamics ; Male ; Rabbits ; Ultrasonography ; Ventricular Function, Left ; Ventricular Pressure

This study was aimed to investigate the effect of stress induced by high-intensity exercises on the cardiovascular system. In the epidemiological investigation, 200 subjects (test group) engaged in special high-intensity exercises, and 97 who lived and worked in the same environment and conditions as those in the test group, but did not participate in the exercises served as controls. In the second part of the study, 50 mice were randomly divided into control group, exhaustive swimming group, white noise group, exhaustive swimming plus white noise group, and pioglitazone intervention group. The results showed that the plasma concentrations of the myocardial injury markers heart fatty acid-binding protein (H-FABP), C-reactive protein (CRP), β-endorphin (β-EP) and levels of psychological stress were significantly increased in test group as compared with control group; special high-intensity exercises resulted in a significant elevation of the incidence of cardiac arrhythmias. Animal experiments showed that the plasma levels of corticosterone (CORT) and troponin I (TnI) were raised while the level of SOD was reduced in exhaustive swimming group, white noise group, and exhaustive swimming plus white noise group. The expression levels of PPARγ mRNA and protein were decreased in myocardial tissues in these groups as well. HE staining showed no remarkable change in myocardial tissues in all the groups. Treatment with pioglitazone significantly decreased the plasma levels of TnI and CORT, while increased the level of SOD and the expression levels of PPARγ mRNA and protein. It was concluded that the high-intensity exercises may induce a heavy physical and psychological stress and predispose the subjects to accumulated fatigue and sleep deprivation; high-intensity exercises also increases the incidence of arrhythmias and myocardial injury. PPARγ may be involved in the physical and psychological changes induced by high-intensity exercises.
Animals ; Heart Injuries ; physiopathology ; Male ; Mice ; PPAR gamma ; genetics ; physiology ; RNA, Messenger ; genetics ; Real-Time Polymerase Chain Reaction ; Stress, Physiological

PURPOSE: The measurement of heart rate variability (HRV) is a non-invasive method to analyze the balance of the autonomic nervous system. The aim of this study was to compare the changes of HRV and base deficit (BD) during the treatment of trauma patients. METHODS: Forty-three trauma patients with a low injury severity scores (ISS < 24) and negative base excess on admission were included in this study. Based on the BD changes, patients were divided into three groups: 'end pointed' group (n = 13), patients' BDs instantly cleared after primary hydration; 'needs further resuscitation' group (n = 21), patients' BDs did not reach the end point and thus required further hydration or packed red blood cells transfusion; and 'hydration minimal change' group (n = 9), patients' BDs lower than 2.5 mmol/L at the onset of admission and thereafter had minimal change (near normal range). The changes in HRV during fluid resuscitation were detected and compared to BD changes in their arterial blood gases. All data were analysed using the SPSS software Version 15.0. Repeated measures ANOVA was used to determine the changes in HRV, heart rate, blood pressure, and BD among groups. RESULTS: A significant reverse correlation was found between the BD ratio and the HRV ratio (r = -0.562; p = 0.01). The HRV of patients with aggravated BDs after fluid resuscitation was decreased. There was an increase in HRV at the time of BD clearance. A decrease in HRV after primary crystalloid hydration bore a significant connection with the need for an ICU (p = 0.021) and transfusion of packed red blood cells (p < 0.001). CONCLUSION Increase in HRV may be a new non-invasive index for the end point of resuscitation in trauma patients.
Adolescent ; Adult ; Aged ; Autonomic Nervous System ; physiopathology ; Crystalloid Solutions ; administration & dosage ; Fluid Therapy ; Heart Rate ; Humans ; Injury Severity Score ; Middle Aged ; Resuscitation ; methods ; Wounds and Injuries ; diagnosis ; physiopathology ; Young Adult

Traumatic tricuspid valve insufficiency (TTVI) is a relatively uncommon disease. To summarize the experience in the diagnosis and treatment of TTVI, we have analyzed the clinical data of 3 patients with TTVI who were admitted to the department of cardiac surgery of our hospital between April 1997 to April 2002. Relevant literatures have also been reviewed.
Accidents, Traffic ; Adult ; Cardiac Surgical Procedures ; methods ; Electrocardiography ; Follow-Up Studies ; Heart Injuries ; diagnosis ; surgery ; Heart Valve Prosthesis ; Humans ; Injury Severity Score ; Male ; Middle Aged ; Multiple Trauma ; physiopathology ; Risk Assessment ; Sampling Studies ; Treatment Outcome ; Tricuspid Valve Insufficiency ; diagnosis ; surgery