A neurosurgical patient who required repeated surgery for intracranial haematoma developed acute respiratory distress syndrome. Raised intracranial pressure proved difficult to manage whilst attempting to maintain optimal gas exchange. The resultant arterial partial pressure of carbon dioxide remained unacceptably high, and treatment by extracorporeal carbon dioxide removal was started. A pumpless arteriovenous interventional lung assist device (Novalung) was connected from the right femoral artery to left femoral vein and reduced the arterial carbon dioxide, corrected the respiratory acidosis and enabled control of the intracranial pressure. Subsequently the requirements for both respiratory and cardiovascular support were reduced. The patient made a complete neurological recovery.