Acute myocardial damage after electrical injury assessed by MRI

Electrical injuries are not uncommon, and electrical shock-induced cardiac damage can be life-threatening. We present the case of a young patient who suffered from acute myocardial damage due to an occupational electric shock. Myocardial damage was assessed by very early (day 4) and repeated (up to month 18) MRI. Clinical management and patient risk estimation in such a setting are challenging because data on similar non-lethal cases and practice recommendations are scarce in the literature.

Different sequelae of electrical brain injury - MRI patterns

PURPOSE

Electrical injury to the central nervous system may lead to neurologic compromise via pleiotropic mechanisms. It may cause current-related, thermal or nonthermal damage followed by secondary mechanisms.

METHODS

We herein report a case of a 20-year old man, who experienced a low-voltage electric injury due to an occupational accident.

RESULTS

Magnetic resonance imaging (MRI) one week after the insult allowed differentiation of pathophysiologic features including thermal, nonthermal and hypoxic cerebral lesions.

CONCLUSION

The capability of MRI assessing a variety of lesions for diagnostic and potentially prognostic reasons is presented.

Identification of Skin Electrical Injury Using Infrared Imaging: A Possible Complementary Tool for Histological Examination

In forensic practice, determination of electrocution as a cause of death usually depends on the conventional histological examination of electrical mark in the body skin, but the limitation of this method includes subjective bias by different forensic pathologists, especially for identifying suspicious electrical mark. The aim of our work is to introduce Fourier transform infrared (FTIR) spectroscopy in combination with chemometrics as a complementary tool for providing an relatively objective diagnosis. The results of principle component analysis (PCA) showed that there were significant differences of protein structural profile between electrical mark and normal skin in terms of α-helix, antiparallel β-sheet and β-sheet content. Then a partial least square (PLS) model was established based on this spectral dataset and used to discriminate electrical mark from normal skin areas in independent tissue sections as revealed by color-coded digital maps, making the visualization of electrical injury more intuitively. Our pilot study demonstrates the potential of FTIR spectroscopy as a complementary tool for diagnosis of electrical mark.

Epileptic seizure in a patient with an implantable cardioverter-defibrillator: Quo vadis right ventricular lead?

The case of a 77-year-old man admitted for suspected epileptic seizure is reported. Patient history showed implantation of a single-chamber implantable cardioverter-defibrillator (ICD) after cardiac arrest in 2007 with replacement in 2012 due to battery depletion; the patient reported no previous syncope, unconsciousness or seizures. Interrogation records of the ICD showed five ventricular tachyarrhythmia episodes that corresponded to the "seizure". Further examination revealed incorrect position of the RV-lead. Diagnosis was a provoked epileptic seizure due to undersensing of ventricular tachycardia because of improper ICD lead implantation in the coronary sinus. Treatment consisted of implantation of a new device with an additional ICD lead into the right ventricle.

Bilateral ultrasound-guided supraclavicular block in a patient with severe electrocution injuries of the upper extremities

The performance of bilateral supraclavicular brachial plexus nerve blocks is controversial. We present the challenging case of a 29-year-old male who suffered bilateral high-voltage electrocution injuries to the upper extremities, resulting in severe tissue damage, sensory and motor deficits, and wounds in both axillae. This injury necessitated bilateral below-elbow amputations. His postoperative course was complicated by pain refractory to intravenous narcotics. The decision was made to attempt bilateral supraclavicular brachial plexus blocks. Our concerns with this approach included the risks of pneumothorax and respiratory failure due to phrenic nerve block. Initial attempts at brachial plexus blockade using nerve stimulation were unsuccessful; therefore, ultrasound guidance was employed. With vigilant monitoring in an intensive care unit setting, we were able to safely perform bilateral continuous supraclavicular brachial plexus nerve blocks with an excellent analgesic response and no noted complications.

Echocardiographic evaluation of a TASER-X26 application in the ideal human cardiac axis

OBJECTIVES

TASER electronic control devices (ECDs) are used by law enforcement to subdue aggressive persons. Some deaths temporally proximate to their use have occurred. There is speculation that these devices can cause dangerous cardiac rhythms. Swine research supports this hypothesis and has reported significant tachyarrhythmias. It is not known if this occurs in humans. The objective of this study was to determine the occurrence of tachyarrhythmias in human subjects subjected to an ECD application.

METHODS

This was a prospective, nonblinded study. Human volunteers underwent limited echocardiography before, during, and after a 10-second TASER X26 ECD application with preplaced thoracic electrodes positioned in the upper right sternal border and the cardiac apex. Images were analyzed using M-mode through the anterior leaflet of the mitral valve for evidence of arrhythmia. Heart rate (HR) and the presence of sinus rhythm were determined. Data were analyzed using descriptive statistics.

RESULTS

A total of 34 subjects were enrolled. There were no adverse events reported. The mean HR prior to starting the event was 108.7 beats/min (range 65 to 146 beats/min, 95% CI = 101.0 to 116.4 beats/min). During the ECD exposure, the mean HR was 120.1 beats/min (range 70 to 158 beats/min, 95% CI = 112.2 to 128.0 beats/min) and a mean of 94.1 beats/min (range 55 to 121 beats/min, 95% CI = 88.4 to 99.7 beats/min) at 1 minute after ECD exposure. Sinus rhythm was clearly demonstrated in 21 (61.7%) subjects during ECD exposure (mean HR 121.4 beats/min; range 75 to 158 beats/min, 95% CI = 111.5 to 131.4). Sinus rhythm was not clearly demonstrated in 12 subjects due to movement artifact (mean HR 117.8 beats/min, range 70 to 152 beats/min, 95% CI = 102.8 to 132.8 beats/min).

CONCLUSIONS

A 10-second ECD exposure in an ideal cardiac axis application did not demonstrate concerning tachyarrhythmias using human models. The swine model may have limitations when evaluating ECD technology.

Free Lateral Arm Flap for 1-Stage Reconstruction of Soft Tissue and Composite Defects of the Hand

In this article, the long-term outcomes of hand defects after 1-stage reconstruction with lateral arm flap were retrospectively analyzed in a large series. Between the years 1990 and 2004, 118 traumatic hand defects were reconstructed using lateral arm fasciocutaneous flap (n = 104), lateral arm fascial flap (n = 6), and composite lateral arm flap (n = 8) in Chang Gung Memorial Hospital. There were 22 females and 96 males with an average age of 32.5 +/- 13.3 years. The mean follow-up period was 17 +/- 6.2 months. The overall success rate was 97.5%. The cosmetic outcomes were satisfactory and only 16.1% of the patients required debulking. The functional recovery of the hand contractures secondary to crush injury were generally associated with poor results. In the composite flap group, reconstruction of the extensor tendons with triceps tendon yielded limitation in tendon excursion and poor functional results. However, complete bone healing without complication was uniformly detected in all cases. Lateral arm fasciocutaneous flap endured secondary interventions well and no complications regarding wound healing was encountered.

Bilateral shoulder fracture dislocations and radiculopathies secondary to electrical injury (a case report)

INTRODUCTION

In this report a case of bilateral shoulder fracture dislocations and C5 radiculopathy developed after an electrical injury is presented.

CASE

A 29 year-old male patient referred to our hospital with complaints of inability to raise his hands overhead starting 3 months ago after an electrical injury. The first physical examination revealed loss of strength (3/5) in deltoid muscles bilaterally, bilateral shoulder fracture dislocations and C5 radiculopathies. An open reduction and internal fixation (using K wire, cortical screw) procedure was applied for the right side in the Department of Orthopedics. Postoperatively active (A) and passive (P) ranges of motion (ROMs) were restricted extremely in the right and left shoulder respectively. Since applications of 15 sessions of electrical stimulation for deltoid muscle and physical treatment for both shoulders failed to achieve satisfactory ROMs, K wire extraction was instituted with resultant increase in the right shoulder A/P ROMs after 10 sessions of physical therapy postoperatively. At the last examination which was 18 months after the injury, ROMs of the right shoulder were increased, but not normal.

CONCLUSION

It must be remembered that in electrical injury, fractures and dislocations might occur in affected sites without any evidence of trauma with associated neurologic complications, and that these cases must be promptly detected and managed without any delay.

High-tension electrical injury to the heart as assessed by radionuclide imaging

To evaluate cardiac complications associated with electrical injury, 7 patients with high-tension electrical injury (6,600 V alternating current) underwent 201Tl and 123I-metaiodobenzylguanidine (MIBG) imaging in addition to conventional electrocardiographic and echocardiographic assessments. Electrocardiography showed transient atrial fibrillation, second degree atrioventricular block, ST-segment depression, and sinus bradycardia in each patient. Echocardiography showed mild hypokinesis of the anterior wall in only 2 patients, but 201Tl and 123I-MIBG myocardial scintigraphy showed an abnormal scan image in 6/7 and 5/6 patients, respectively. Decreased radionuclide accumulation was seen primarily in areas extending from the anterior wall to the septum. Decreased radionuclide accumulation was smaller in extent and milder in degree in 123I. MIBG than in 201Tl imaging. These results suggest that even in patients without definite evidence of severe cardiac complications in conventional examinations, radionuclide imaging detects significant damage due to high-tension electrical injury, in which sympathetic nerve dysfunction might be milder than myocardial cell damage.

[Trans-scaphoid perilunar dislocation of the wrist (de Quervain) as a rare complication of electric injury]

We describe the case of a 67-year-old man with an electricity inflicted injury in the left hand and a transscaphoidal perilunear dislocation of the opposite right hand. On admission, the injury was missed on the standard ap-radiogram of the right hand, so the operative reconstruction was delayed. Later on, the lunate showed aseptic necrosis and wrist collapse as consequence.

[The changes in arteriography in extremities sustaining high tension electric injuries]

OBJECTIVE

Because it is difficult to estimate the extent and degree of damage to the blood vessels of extremities sustaining high tension electrical injuries, arteriography was carried out to evaluate the vascular changes.

METHODS

Selective arteriography was carried out 29 times for 26 extremities in 17 patients suffering from > 380 V electrical injuries.

RESULTS

The arteriography showed that the injured arteries were narrowed and occluded, and vascular branches decreased or disappeared. Recanalization of the partially occluded arteries or collateral circulation formation was found after decompression.

CONCLUSION

Arteriography is valuable to evaluate the vascular changes in high tension electrical injuries of extremities.

Myocardial necrosis by electrocution: evaluation of noninvasive methods

We present the case of a young man who suffered severe anteroapical myocardial necrosis caused by electrocution. In addition to the enzymatic and electrocardiographic changes suggesting necrosis, a clear positive segmental image on 99mTc-pyrophosphate scintigraphy and a defect on a 201Tl SPECT scan at rest were also found. Although these tests were indicative of extensive anteroapical transmural myocardial necrosis, the echocardiographic study only revealed mild anteroapical hypokinesia.

[Pulmonary lesion in electric injury: report of a case]

Major electrical injuries constitute approximately 5% of all admissions to Burn Units. Visceral complications are associated with a high mortality rate. The most common visceral lesions associated to electric burns are cardiac lesions. Pulmonary compromise is rare, if compared to inhalation injuries in termical burns. Although, when the entry or exit ports are the toracic wall, pleural effusion, hemotorax and pneumonitis may occur. A rare case of high-voltage electrical injury with massive pulmonary lesion is presented, regarding to clinical course and roentgenographic patterns.

High-voltage electric injury: assessment of muscle viability with MR imaging and Tc-99m pyrophosphate scintigraphy

PURPOSE

To evaluate use of magnetic resonance (MR) imaging and technetium-99m pyrophosphate (PYP) scintigraphy in preoperative assessment of muscle viability after high-voltage electric injury.

MATERIALS AND METHODS

Twelve injured limbs were studied. Immediate, equilibrium, and delayed Tc-99m PYP scintigrams and gadolinium-enhanced and unenhanced MR images were obtained. Imaging results were compared with clinical findings.

RESULTS

Scintigraphy demonstrated nonperfusion in four limbs that were subsequently amputated, but MR imaging had poor sensitivity in nonperfused regions owing to lack of edema. Tc-99m PYP uptake increased at transition zones between normal and nonperfused regions. MR imaging allowed further characterization of these zones by demonstrating edema as enhancing (perfused) or nonenhancing (nonperfused). In all nonamputated limbs, edema showed enhancement.

CONCLUSION

In high-voltage electric injury, gadolinium-enhanced MR imaging appears able to demonstrate zones of potential viability within radionuclide-avid tissue but has poor perfusion sensitivity when used alone.

A miniature gamma camera

We have described a mobile miniature-gamma-camera system for use in electrical trauma units and have presented images and imaging characteristics of a prototype system. The system has as its principal component a miniature gamma camera based on a PSPMT. The camera is 92 mm x 92 mm x 190 mm in size, weighs 5 kg, has a 48 mm x 48 mm field of view, and has an intrinsic resolution of approximately 3 mm FWHM and 6 mm FWTM. It is expected that devices of this type will be useful as imaging tools in electrical trauma units and laboratories where imaging studies regarding uptake mechanisms of radiopharmaceuticals for assessing tissue viability are carried out.

Bilateral scapular fractures secondary to electrical shock

Fractures of the scapula are rare injuries. Usually the scapula requires a high-energy impact to sustain a fracture. Various fractures have been noted as a result of convulsive seizures. We report bilateral scapular fractures caused by electric shock and discuss their pathomechanical origin.

Angiographic findings and need for amputation in high tension electrical injuries

Because it is difficult to estimate the extent of deep tissue injury clinically, angiography was carried out in 28 patients with signs of damage from current flow through the body. Eight of the arteriograms showed normal extremities, 6 showed changes of small arteries, and 38 showed injury to the main arteries. In the latter group there were 24 total arterial occlusions, narrow irregular lumens in 10, and 4 had occlusion and distal refilling. Changes in the main arteries were most often seen near major joints where the internal body resistance as well as the density of the current are higher. Injury to the main arteries resulted in severe neuromuscular damage or amputation of the limb, whereas injury to small arteries resulted in little functional deficit. Of the 25 amputations 19 were at the level of the arterial occlusion. Spasmolytic drugs did not increase filling. We conclude that early angiography is valuable for the detection of deep injury and often indicates the level of adequate amputation or the need for immediate exploration. In some patients it indicates the necessity for arterial reconstruction.

Shoulder injury caused by electric shock

Shoulder injury and more in particular bilateral dislocation of the shoulder joint after electric shock is rare. Three patients are presented with dislocation and fracture of the shoulder and serious muscle contraction. After an accident involving electric current potential shoulder injuries should be considered. Early diagnosis improves the functional results of adequate treatment.

Accidental high voltage electrocution: a rare neurosurgical problem

The authors describe a case of accidental electrocution from a high voltage current in a young worker, who was struck by the electric shock in the mid-occipital region. The case is especially interesting due to the improbability of anyone surviving after receiving a shock of more than 1000 V., and to the development of bilateral parieto-occipital haemorrhagic infarction with spastic paraparesis, directly caused by the high voltage current and not indirectly by heat generation or secondary head trauma.

[Bone scintigraphy in high-voltage injury to the skull]

This is a report on the use of skeletal scintigraphy in skull injury caused by power current (heavy current). Nuclear medicine offers the advantage compared with x-ray technique of early and safe assessment of the vitality of the injured bone. This is of course of great value for selecting the appropriate therapy.

Tc-99m PYP scanning following low voltage electrical injury

An adolescent boy sustained low voltage electrical injury to his extremities when he inadvertently touched a low tension (440 volts) wire with a metal tube. Early in his hospital course, he was evaluated with Tc-99m pyrophosphate whole body scanning for the extent of his injuries. The scintigraphic findings correlated well with his subsequent clinical course.

Role of cardiovascular nuclear medicine in evaluating trauma and the postoperative patient

In the patient with cardiac trauma, radionuclide imaging may provide important information about cardiac mechanical function, vascular anatomy and integrity, myocardial perfusion, and myocardial metabolism. Studies require only minimal patient cooperation, can be performed relatively rapidly and often at the bedside, and may be repeated at frequent intervals for serial evaluations. These studies provide valuable adjunctive knowledge when selected and interpreted with knowledge of the mechanism of injury, timing of the examination relative to the time of injury, and most likely differential diagnoses.

Radionuclide evaluation of cardiac trauma

Radionuclides were first used in the evaluation of myocardial trauma as a noninvasive means to detect hemopericardium. At present an important use is in the diagnosis of myocardial contusion, which can be difficult to recognize clinically, and often has nonspecific EKG and enzyme alterations. Technetium-99m pyrophosphate scintigraphy has been shown to be of significant value in confirming this diagnosis. Myocardial scintigrams are helpful in determining the degree of damage produced by penetrating wounds of the heart and can also detect electrical injury to the heart from accidental shock or cardioversion. In addition, multiple gated blood pool scans can determine the hemodynamic significance of mycardial trauma and evaluate for late sequelae such as aneurysm formation.

Cardiac damage produced by direct current countershock applied to the heart

This study examined the pathophysiology of the myocaridal damage produced by direct current shock over a dose range of 10 to 90 watt-seconds, applied directly to the heart in 26 dosgs. The extent of injury produced was assessed with creatine kinase depletion and light and electron microscopy, and was correlated with in vivo imaging and tissue distributions of the isotopes technetium-99m pyrophosphate and thallium-201. Changes in intramyocardial temperature and regional myocardial blood flow were also measured. Uptake of technetium-99m pyrophosphate occurred exponentially with graded increases in shocks, and this agent was more sensitive than thallium-201 in detecting injury both on imaging and at tissue level. The threshold for significant injury was approximately 30 watt-seconds, and on electron microscopy a characteristic feature was marked dehiscence of the intercalated disks between the damaged myocytes. The use of different-size paddles did not appear to affect the total number of cells damaged. However, with large paddles the injury was more superficial and spread over a wider area. With short time intervals between successive shocks, a greater amount of injury occurred, in part because of a compounding of the thermal component of the damage. Hypothermia can reduce the degree of injury.