A 73-year-old woman was scheduled for brachial shunt surgery. She received regional anaesthesia of the right brachial plexus via a supraclavicular approach. During surgery we noticed acute dyspnoea with a saturation reduction. A postoperative chest X-ray showed a high position of the right diaphragm, which was caused by a phrenic nerve blockade due to the anaesthesia. This completely disappeared within 24 hours.