You can generally predict that intubation will be difficult if the patient has a history of difficult intubation , limited neck mobility , a small mandible , pharyngeal structures that are poorly visible through the open mouth with tongue extruded , a limited ability to open his or her mouth , or a laryngeal prominence that is close to the mentum 通常你能够预测到，以下情况插管会比较困难：如患者既往有插管困难的病史、颈部活动度受限、鄂部较小、通过开口牵拉舌而咽部结构可视度差、口腔开口受限、喉结与颏部较近等。
