When the bronchoscope and the esophagoscope were invented, these instruments were used primarily for the removal of foreign objects from the passages devoted to the movement of air and food. Although extraction of foreign bodies continues to be an important function of the modern endoscopist, his practice now is devoted chiefly to diagnosis rather than treatment; in fact, peroral endoscopy has become indispensable to the diagnosis of diseases of the respiratory tract and upper part of the alimentary tract.
Endoscopic procedures must be carried out with minimal discomfort to the patients. Lurid accounts of the procedures by patients who have undergone endoscopy are no boon to the specialty, nor do they reflect credit on the examining physician. If endoscopic methods of diagnosis are to remain in favor with both patients and referring physicians, the examinations must be performed quickly and skilfully, with minimal risk to the patient. Complications do occur
Olsen AM, Pender JW. PREPARATION OF PATIENTS FOR PERORAL ENDOSCOPY. JAMA. 1952;150(9):842-844. doi:10.1001/jama.1952.03680090006003