Abstract: An endotracheal intubation device for determining correct placement of an endotracheal tube in the trachea, or windpipe, of a medical patient by detecting the presence of carbon dioxide in expired air. The portable, reusable endotracheal intubation device includes a material capable of physically and/or chemically interacting with carbon dioxide, such as barium hydroxide or calcium oxide, and a visual indicating material, such as an acid-base indicator that changes color in relation to pH changes, like ethyl violet or thymolphthalein, whereby the visual indicating material changes color in response to the interaction of the carbon dioxide with the interactant material. The visual color change of the chemical reagent materials present in the endotracheal intubation device confirms the placement of the endotracheal tube within the trachea as opposed to within the esophagus.