University of Nebraska Medical Center, Department of Emergency Medicine, Omaha, NE.
West J Emerg Med. 2010 May;11(2):180-5.
Pneumocephalus typically implies a traumatic breach in the meningeal layer or an intracranial gas-producing infection. Unexplained pneumocephalus on a head computed tomography (CT) in an emergency setting often compels emergency physicians to undertake aggressive evaluation and consultation.
In this paper, we report three cases of pneumocephalus that appear to result from retrograde injection of air through an intravenous (IV) catheter. We also performed a retrospective study to determine the incidence of presumed IV-induced pneumocephalus and etiologies of pneumocephalus in our emergency department (ED) population.
The incidence of idiopathic and presumed IV-induced pneumocephalus was 0.034% among all head CTs ordered in the ED and 4.88% among cases of pneumocephalus seen in the ED. These cases are characterized clinically by the absence of signs and symptoms of pathologic pneumocephalus and radiographically by the distribution of air densities along the cranial venous system on head CTs.
Idiopathic and presumed IV-induced pneumocephalus could be considered in the workup of ED patients with unexplained intracranial air on head CT if there are no findings of pathological causes for the pneumocephalus on history and physical examination and if the head CTs show a characteristic distribution of air limited to the cranial venous system. Knowledge of this clinical entity in the evaluation of ED patients with unexplained pneumocephalus can lead to more efficient emergency care and less patient anxiety.
通常情况下， 气胸提示脑膜层有创伤性破裂或颅内产气感染。在急诊情况下， 头部计算机断层扫描（CT） 上出现不明原因的气胸往往迫使急诊医生进行积极的评估和咨询。
在本文中， 我们报告了三例似乎由于静脉（IV） 导管逆行注射空气引起的气胸病例。我们还进行了一项回顾性研究， 以确定在我们的急诊部（ED） 人群中， 推测的 IV 引起的气胸和气胸的病因的发生率。
在 ED 中所有头部 CT 检查中， 特发性和推测的 IV 引起的气胸的发生率为 0.034%， 在 ED 中所见的气胸病例中为 4.88%。这些病例在临床上的特点是没有病理气胸的迹象和症状， 影像学上表现为头部 CT 上沿颅静脉系统分布的空气密度。
如果病史和体格检查中没有气胸的病理原因， 并且头部 CT 显示空气局限于颅静脉系统的特征性分布， 则在对头部 CT 显示不明原因颅内气的 ED 患者进行检查时， 可以考虑特发性和推测的 IV 引起的气胸。在对 ED 中不明原因气胸的患者进行评估时， 了解这一临床实体可以使急诊护理更加有效， 减少患者的焦虑。
