 The decision to use a straight or curved laryngoscope blade depends partly on the specific anatomical features of the airway , and partly on the personal experience and preference of the laryngoscopist . The Macintosh blade is the most widely used curved laryngoscope blade , while the Miller blade is the most popular style of straight blade . Both Miller and Macintosh laryngoscope blades are available in sizes 0 ( infant ) through 4 ( large adult ) . There are many other styles of straight and curved blades , with accessories such as mirrors for enlarging the field of view and even ports for the administration of oxygen . These specialty blades are primarily designed for use by <unk> and <unk> , most commonly in the operating room . 
