Acute intraventricular hemorrhage triggered by coughing following return from high altitude: a case report and literature review.

Background: Exposure to high-altitude conditions can lead to significant physiological stress and elevate the risk of cerebrovascular incidents. Nevertheless, intraventricular hemorrhage (IVH) caused by a minor trigger such as coughing shortly after returning from brief high-altitude travel remains highly uncommon. Case Presentation: A 30-year-old woman with no significant prior medical history developed a sudden thunderclap headache and began vomiting right after a strong cough. This occurred on the day she came back to Xi'an (400 m) from a four-day visit to Xining (2,260 m), where she had experienced considerable sleep disruption. A non-contrast head CT scan showed bleeding inside the ventricular system. Subsequent CT angiography (CTA) did not detect any aneurysms or vascular malformations. She was successfully treated with a neuronavigation-assisted endoscopic procedure to remove the intraventricular hematoma, along with intracranial pressure (ICP) monitoring. After surgery, she recovered smoothly and showed marked neurological improvement. Conclusion: This case indicates that even brief stays at moderately high altitude may impair cerebrovascular self-regulation and increase stress on blood vessel walls. The resulting instability in blood flow during re-adaptation to lower elevation, combined with a sudden rise in intracranial pressure from a Valsalva-type action such as coughing, could lead to the rupture of susceptible vessels. Medical practitioners should consider this possible cause in cases of neurological emergency where there is a recent history of high-altitude exposure.