In medical procedures requiring access to the stomach, such as insertion of a nasogastric tube (also known as NG tube), verification is required that the tube has indeed reached the stomach and did not find its way into another organ such as the lungs. The invention provides a simple and foolproof way of establishing that the stomach was reached. The method does not require any additional training of the medical staff. The invention can be used in conjunction with an NG tube and provides feedback to the user when the NG tube is correctly inserted in the stomach by detecting the presence of Gastric acid.
