title: Tension pneumocephalus: an uncommon cause of altered mental status.
abstract: BACKGROUND
  Pneumocephalus is a rare cause of altered mental status in patients presenting to the Emergency Department. Occurring as a result of traumatic or iatrogenic violation of the dura, it can cause significant morbidity and mortality if tension physiology develops whereby air continues to accumulate with no mechanism for escape.
  
  
  OBJECTIVE
  This case report will review the underlying pathophysiology, clinical presentation, diagnosis, and management of tension pneumocephalus.
  
  
  METHODS
  We present the case of an 89-year-old man who presented to the Emergency Department with declining mental status 9h after endoscopic sinus surgery. He was subsequently found to have tension pneumocephalus and underwent emergent burr hole evacuation. Despite resolution of the pneumocephalus, the patient had persistent neurologic deficits related to ischemic infarcts that occurred as a result of the tension physiology and subsequently expired in the hospital.
  
  
  CONCLUSIONS
  This case illustrates the importance of considering tension pneumocephalus on the differential diagnosis for any patient presenting with altered mental status after surgical or diagnostic procedures with potential to violate the dural space.
authors.affiliation: Department of Emergency Medicine, Madigan Army Medical Center, Tacoma, Washington, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: Simmons
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Luks
mesh_terms: D000369:Aged, 80 and over; D003221:Confusion / Q000209:etiology*; D004724:Endoscopy / Q000009:adverse effects; D006261:Headache / Q000209:etiology*; D006801:Humans; D008297:Male; D009460:Neurologic Examination; D010254:Paranasal Sinus Diseases / Q000601:surgery; D011007:Pneumocephalus / Q000150:complications / Q000175:diagnosis* / Q000209:etiology; D014057:Tomography, X-Ray Computed; D014839:Vomiting / Q000209:etiology