A 37-year-old man is found unresponsive under a tree during a thunderstorm. He is not breathing when paramedics arrive on the scene. On examination, his pupils are fixed and dilated. Several cutaneous erythematous marks in a fern-leaf pattern are seen on his lower extremities. Second-degree burns are present on both arms. Cardiopulmonary resuscitation is started; however, the patient does not respond and is pronounced dead on arrival at the hospital. Which of the following is most likely to be the primary cause of his death?

Question

A 37-year-old man is found unresponsive under a tree during a thunderstorm.  He is not breathing when paramedics arrive on the scene.  On examination, his pupils are fixed and dilated.  Several cutaneous erythematous marks in a fern-leaf pattern are seen on his lower extremities.  Second-degree burns are present on both arms.  Cardiopulmonary resuscitation is started; however, the patient does not respond and is pronounced dead on arrival at the hospital.  Which of the following is most likely to be the primary cause of his death?

Quizplus · Accepted Answer

11ec160b_38cc_09d1_9249_29249f3f8a6d_MD0001_00 The finding of an unconscious person on wet ground or under trees during a thunderstorm suggests a lightning injury. This patient's Lichtenberg figures (erythematous cutaneous marks in a fern-leaf pattern) and second-degree burns confirm the suspicion. Although lightning injuries are rare, they are associated with a 25% fatality rate, and more than 70% of survivors have long-lasting complications. Two-thirds of lightning-related deaths occur within the first hour following injury; the most common causes are fatal arrhythmias and respiratory failure. A comprehensive and thorough physical examination should always be performed on lightning strike victims as injury patterns are widely variable and skin findings can significantly underestimate the extent of internal injury. (Choice B) Superficial burns are common in lightning injury. In contrast, deep-tissue burns are relatively rare due to the short duration of electrical contact and the "flashover effect," the tendency of lightning to travel over the skin surface and discharge to the ground. This effect is responsible for the formation of Lichtenberg figures. (Choice C) Intracranial hemorrhage only rarely occurs following lightning injury. Lightning strikes can damage the autonomic system and cause fixed and dilated or asymmetric pupils. These signs may not accurately reflect the extent of neurologic injury and should not be a reason to stop resuscitation. (Choices D and E) Lightning induces rapid heating of the surrounding air, generating shock waves that can travel through the body and cause mechanical trauma. As a result, patients should be thoroughly assessed for skeletal fractures. Myocardial contusion and pulmonary barotrauma occur less frequently and would be extremely rare causes of death. Educational objective: Although lightning injuries are rare, they are associated with a 25% fatality rate. Two-thirds of lightning-related deaths occur within the first hour after injury, with fatal arrhythmias and respiratory failure as the most common causes. Patients with minor cutaneous involvement may still have major internal injury after lightning strikes and high-voltage electrical contact. __________ References: Emergent care of lightning and electrical injuries. (http://www.ncbi.nlm.nih.gov/pubmed/8570929)

A 37-Year-Old Man Is Found Unresponsive Under a Tree During