Figure 2From: A feasibility study on bedside upper airway ultrasonography compared to waveform capnography for verifying endotracheal tube location after intubation Oesophageal intubation. (a) US shows empty trachea. (b) Moving the probe to the left shows a dilated oesophagus. c. Focus on the oesophagus shows an endotracheal tube inside the oesophagus evidenced by two hyper-echoic lines inside oesophagus.Back to article page