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A patient is described who presented with the clinical picture of respiratory failure, persistent comatose state and myocardial injury after being struck by lightning. The discussion reviews the management of lightning injuries with emphasis on cardiovascular and neurological complications.
Environmental injuries and illnesses can happen in home, work, or recreational settings. The variety and severity of these injuries might require the clinician to call on skills from internal medicine, emergency medicine, and toxicology. Diseases of thermoregulation are hypothermia and hyperthermia. In each instance, treatment is based on the need to restore the patient's core temperature to normal and on monitoring for complications. The victim of a fire might suffer inhalation injury in addition to burns, and it is more likely that the inhalation injury will be fatal. Oxygen deprivation and inhalation of irritant or asphyxiant chemicals contribute to injury. Toxic plants can be the source of poisoning emergencies, especially in children. Misinformation and myths that surround common plants can create diagnostic problems (i.e., which plants really are toxic and require emergency measures). Venomous marine organisms can cause a wide range of injury, from cutaneous eruption to fatal envenomation. Most are encountered in a recreational setting, such as water sports, but keepers of home aquariums are subject to stings from venomous fish. Lightning injury can present many diagnostic and treatment dilemmas. An important point in this regard is that lightning injury and high-voltage electrical injury are different in pathology and require different approaches for treatment. A discussion of electrical, chemical, and thermal burns makes such differences apparent.
Electric current can damage an individual by thermal heating of the tissues; by disregulating autonomously functioning organ systems, such as the circulatory and respiratory systems; or by once-only or continuing stimulation of the nerves and striated muscles. In the first case, the result is coagulation necrosis, and in the second case life-threatening events can occur, such as arrhythmia or apnea. In the third case, vigorous nerve stimulation can lead to paralysis and vasospasm. Massive muscle contractions due to nerve stimulation or the direct triggering of striated muscles can cause ruptures, ligamentous tears, fractures, and joint dislocations, while prolonged current passing through the thoracic wall may stimulate tetany of the intercostal muscles and diaphragm resulting in asphyxia. This article is confined to a description of thermal or Joule heating of tissues when they form part of an electric circuit and to the effects of direct nerve and muscle stimulation. Other articles discuss nonthermal effects. The injuries a person sustains as the result of an electrical accident depend on a large number of interrelated factors, such as the properties of the electrical power supply, the magnitude and duration of current flow, the current pathway, and skin conditions. It makes a vast difference whether a person is hit by a lightning bolt (extremely high voltage, short current flow) or receives a shock from an electrical power supply (low to high voltage, relatively long current flow). Wide variation in the physical properties of lightning discharges and the discharges from electrical power supplies at home and in industry means that all kinds of injuries can be encountered.
An analysis of 45 victims of fatal lighting strike revealed the incident occurred most frequently in the early afternoon during midsummer in a field of one form or another. The scene of death, damage to clothing, and alterations of metallic objects on the victim are described. A terminal cardiac rhythm of ventricular fibrilation was recorded in half for whom data were available, and asystole was found in 40%. All but four had cutaneous injuries, and nearly one-third had pathognomonic patterns of erythematous arborization. When examined, tympanic membranes were found to be ruptured in > 80%. This study also revealed that craniocerebral injury and cardiac contusion can be serious direct consequences of lightning strike. A correlative approach to the investigation and autopsy of lightning victims is suggested.
The majority of cutaneous injuries seen in victims struck by lightning are superficial and heal without sequelae. Common cutaneous findings associated with lightning strike include punctate full-thickness burns, linear charring, and contact burns from overlying metal objects. Branching or ferning marks are an uncommon and unusual cutaneous manifestation. These ferning patterns are called Lichtenberg figures. Similar-appearing electrical phenomena were first noted by an 18th-century physicist of the same name. A case report with review of the literature is presented. The histopathologic features of the figures are described for the first time.
Spark discharge method was used to take simulative investigations on the conversion reaction from CS2 to COS by lightning. The results showed that 1.33 x 10(3) Pa CS2 could act with O2 or H2O in the atmosphere (25 degrees C, 10(5) Pa) under electric discharge conditions (V = 3000 V), and COS was produced as well as other species such as CO, CO2, SO2 and so on. Factors such as CS2 concentration, water vapor and discharge time played important roles in the formation of COS. Based on these results and several theories, possible mechanisms of correlative processes during thunderstorms were proposed here, which could contribute to give evidence for the conversion from CS2 to COS by lightning during thunderstorms.
Recreational activity sometimes leads to injury caused by environmental conditions, such as lightning. A familiarity with the effects of electricity, lightning, hyperthermia, and poisoning is essential for providers of care to the critically injured. This article discusses the pathophysiology and treatment of injuries caused by the environment.
OBJECTIVE: To assess the effectiveness of diphenhydramine hydrochloride (Benadryl) in the treatment of patients with idiopathic truncal dystonia. DESIGN: Before-and-after trial. SETTING: University referral center. PATIENTS: Five consecutive patients with idiopathic truncal dystonia who were poorly treated with conventional pharmacotherapies. No patients were withdrawn from the trial for adverse side effects. INTERVENTIONS: Treatments with diphenhydramine hydrochloride (50 mg intravenously or up to 500 mg/kg orally). Follow-up for up to 20 months. MAIN OUTCOME MEASURE: Dystonia evaluation. RESULTS: Diphenhydramine therapy was associated with minimal side effects, and it was most effective in treating patients with dystonia who experienced lightning jerks. Treatment with intravenous diphenhydramine may have a predictive value on a future response to oral therapy. CONCLUSION: Diphenhydramine should be considered a therapeutic option for idiopathic truncal dystonia with lightning jerks.
A man of 75 years of age had had lightning pains in the legs for 8 years. Clinical examination demonstrated mild pyramidal signs and involvement of the posterior columns. A morphine pump was placed in the epidural space in the lumbar region to treat the pain. He died two weeks later from a massive pulmonary embolism. The nervous system was examined using the classical techniques along with the use of poly- and monoclonal antibodies against nervous system specific proteins. The following features were demonstrated: neuroaxonal dystrophy of the posterior and anterior horns, and the posterior columns and corticospinal pathways in decreasing order of importance; angioneuromatosis of the grey matter of the lumbosacral spinal cord and loss of neurons of the dorsal spinal root ganglia and bilateral degeneration of the fasciculus gracilis. Previously, we have only found such amounts of spheroids in the spinal cord as measured here in cases of Seitelberger's disease. The angioneuromatosis was isolated and did not result from previous trauma nor was it associated with a known phacomatosis. This combination of features is very unusual and may explain the clinical features including the lightning pains.
Prebiotic electric discharge and ultraviolet light experiments are usually reported in terms of carbon yields and involve a large input of energy to maximize yields. Experiments using lower energy inputs are more realistic prebiotic models and give energy yields which can be used to estimate the relative importance of the different energy sources on the primitive earth. Simulated prebiotic atmospheres containing either CH4, CO or CO2 with N2, H2O and variable amounts of H2 were subjected to the spark from a high frequency Tesla coil. The energy yields for the synthesis of HCN and H2CO were estimated. CH4 mixtures give the highest yields of HCN while H2CO is most efficiently produced with the CO mixtures. These results are a model for atmospheric corona discharges, which are more abundant than lightning and different in character. Preliminary experiments using artificial lightning are also reported. The energy yields from these experiments combined with the corona discharge available on the earth, allows a yearly production rate to be estimated. These are compared with other experiments and model calculations. From these production rates of HCN (e.g. 100 nmoles cm-2 yr-1) and the experimental hydrolysis rates, the steady state concentration in the primitive ocean can be calculated (e.g., 4 X 10(-6) M at pH 8 and 0 degrees). A steady state amino acid concentration of 3 X 10(-4) M is estimated from the HCN production rate and the rate of decomposition of the amino acids by passage through the submarine vents.
Considerable hemorheological changes and depression of EEG parameters were revealed in rats with cerebral ischemia. Course peroral treatment with scarlet lightning extract in a daily dose of 150 mg/kg for 5 days reduced the severity of hemorheological disorders. It manifested in a decrease in whole blood viscosity, plasma viscosity, erythrocyte aggregation, and fibrinogen concentration and increase in deformability. The extract of lightning extract improved EEG activity in rats with cerebral ischemia.
Point prevalence of specific fears and phobias was determined in 704 respondents of 1000 randomly selected adults aged 18-70 yr. A phobia for lightning, enclosed spaces, darkness, flying, heights, spiders, snakes, injections, dentists and/or injuries was defined if subjects reported a fear that was out of conscious control, interfered with life and lead to the avoidance of the feared object [American Psychiatric Association, 1994. Diagnostic and statistical manual of mental disorders (4th edn). Washington, DC: American Psychiatric Press.] Fear intensity was assessed using visual analogue scales. A factor analysis generally supported the classification of fears and phobias into: (1) situational phobias (lightning, enclosed spaces, darkness, flying and heights); (2) animal phobias (spiders and snakes); and (3) mutilation phobias (injections, dentists, injuries). Total point prevalence of any specific phobia was 19.9% (26.5% for females and 12.4% for males). In total, 21.2% women and 10.9% men met criterias for any single specific phobia. Multiple phobias was reported by 5.4% of the females and 1.5% of the males. Animal phobia had a prevalence of 12.1% in women and 3.3% in men. Point prevalence of situational phobia was 17.4% in women and 8.5% in men. For mutilation phobia no gender difference was observed, being presented in 3.2% of the women and 2.7% of the men. Women as compared to men gave higher fear ratings for all objects and situations. Inanimate object fears and phobias were more common in older than younger individuals. Animal fears were more intense in younger than in older individuals. Fear of flying increased and fear of injections decreased as a function of age in women but not in men. Thus, specific fears and phobias are heterogeneous with respect to sex and age distribution.
Chick pineal cells contain a circadian oscillator that derives rhythmic synthesis and secretion of melatonin even in dispersed cell culture. Here, we demonstrate that the mRNA encoding tryptophan hydroxylase (TPH), the first enzyme in the melatonin synthetic pathway, is expressed rhythmically under the control of the circadian clock. TPH message levels doubled between early day and early night, under both cyclic lightning and constant lightning conditions. The amplitude of the TPH mRNA rhythm was increased to 4-fold by culturing the cells at 43.3 degrees C for 48 h instead of 36.7 degrees C. Addition of forskolin to the cultures in early day produced a modest increase (50%) in TPH message levels but had no effect at other times. Because TPH mRNA are regulated by the endogenous pineal circadian clock, this provides a valuable system in which the molecular mechanism of clock control of gene expression.
Four experiments examined new associative learning in amnesia by contrasting the performance of 2 amnesic participants-1 (C.C.) with basal forebrain damage and the other (R.H.) with medial temporal lobe damage--and 3 controls. Both amnesic individuals were severely impaired on explicit memory measures but showed intact perceptual priming. On the new associations measures, only C.C., not R.H., exhibited learning by producing correct targets (HIJACKER) in the absence of perceptual cues for them (e.g., STAFF shot ???). When the perceptual cue (e.g., MEDICINE cured _I_C_P) was provided, both C.C. and R.H. showed learning. Transfer to information containing conceptually related targets (e.g., TERRORIST or BELCH) was reliably observed only in C.C. This finding was replicated with further reduction in perceptual overlap across original (LIGHTNING torched JUNGLE) and transfer (LIGHTNING burned WILDERNESS) sentences. Together, these findings delineate the role of experimental conditions, severity of amnesia, and different neuroanatomical structures in mediating new verbal learning in amnesia.
On the basis of previous ground-based and fly-by information, we knew that Titan's atmosphere was mainly nitrogen, with some methane, but its temperature and pressure profiles were poorly constrained because of uncertainties in the detailed composition. The extent of atmospheric electricity ('lightning') was also hitherto unknown. Here we report the temperature and density profiles, as determined by the Huygens Atmospheric Structure Instrument (HASI), from an altitude of 1,400 km down to the surface. In the upper part of the atmosphere, the temperature and density were both higher than expected. There is a lower ionospheric layer between 140 km and 40 km, with electrical conductivity peaking near 60 km. We may also have seen the signature of lightning. At the surface, the temperature was 93.65 +/- 0.25 K, and the pressure was 1,467 +/- 1 hPa.
Chondrules are millimetre-sized spherules (mostly silicate) that dominate the texture of primitive meteorites. Their formation mechanism is debated, but their sheer abundance suggests that the mechanism was both energetic and ubiquitous in the early inner Solar System. The processes suggested--such as shock waves, solar flares or nebula lightning--operate on different length scales that have been hard to relate directly to chondrule properties. Chondrules are depleted in volatile elements, but surprisingly they show little evidence for the associated loss of lighter isotopes one would expect. Here we report a model in which molten chondrules come to equilibrium with the gas that was evaporated from other chondrules, and which explains the observations in a natural way. The regions within which the chondrules formed must have been larger than 150-6,000 km in radius, and must have had a precursor number density of at least 10 m(-3). These constraints probably exclude nebula lightning, and also make formation far from the nebula midplane problematic. The wide range of chondrule compositions may be the result of different combinations of the local concentrations of precursors and the local abundance of water ice or vapour.
Two coupled climate-chemistry model experiments for the period 1990-2030 were conducted: one with a fixed climate and the other with a varying climate forced by the is92a scenario. By comparing results from these experiments we have attempted to identify changes and variations in physical climate that may have important influences upon tropospheric chemical composition. Climate variables considered include: temperature, humidity, convective mass fluxes, precipitation, and the large-scale circulation. Increases in humidity, directly related to increases in temperature, exert a major influence on the budgets of ozone and the hydroxyl radical: decreasing 03 and increasing OH. Warming enhances decomposition of PAN, releasing NOx, and increases the rate of methane oxidation. Surface warming enhances vegetation emissions of isoprene, an important ozone precursor. In the changed climate, tropical convection generally reduces, but penetrates to higher levels. Over northern continents, convection tends to increase. These changes in convection affect both vertical mixing and lightning NOx emissions. We find no global trend in lightning emissions, but significant changes in its distribution. Changes in precipitation and the large-scale circulation are less important for composition, at least in these experiments. Higher levels of the oxidants OH and H202 lead to increases in aerosol formation and concentrations. These results indicate that climate-chemistry feedbacks are dominantly negative (less 03, a shorter CH4 lifetime, and more aerosol). The major mode of inter-annual variability in the is92a climate experiment is ENSO. This strongly modulates isoprene emissions from vegetation via tropical land surface temperatures. ENSO is also clearly the dominant source of variability in tropical column ozone, mainly through changes in the distribution of convection. The magnitude of inter-annual variability in ozone is comparable to the changes brought about by emissions and climate changes between the 1990s and 2020s, suggesting that it will be difficult to disentangle the different components of near-future changes.
Wildfires statistics for the conterminous United States (U.S.) are examined in a spatially and temporally explicit manner. We use a high-resolution data set consisting of 88,916 U.S. Department of Agriculture Forest Service wildfires over the time period 1970-2000 and consider wildfire occurrence as a function of ecoregion (land units classified by climate, vegetation, and topography), ignition source (anthropogenic vs. lightning), and decade. For the conterminous U.S., we (i) find that wildfires exhibit robust frequency-area power-law behavior in 18 different ecoregions; (ii) use normalized power-law exponents to compare the scaling of wildfire-burned areas between ecoregions, finding a systematic change from east to west; (iii) find that wildfires in the eastern third of the U.S. have higher power-law exponents for anthropogenic vs. lightning ignition sources; and (iv) calculate recurrence intervals for wildfires of a given burned area or larger for each ecoregion, allowing for the classification of wildfire regimes for probabilistic hazard estimation in the same vein as is now used for earthquakes.