Optimizing the timing of painless gastroscope insertion: integrating advanced monitoring tools to enhance safety and efficacy: a narrative review.

Painless gastroscopy demonstrates significant improvement in patient comfort and examination compliance, which might indicate that the procedure has become commonly used in clinical practice. However, the critical step of accurately determining insertion timing could present challenges, given that unified standards and objective criteria appear to be lacking. Moreover, improper timing of insertion may increase patient discomfort and the risk of procedural complications while potentially affecting diagnostic accuracy. Traditionally, the eyelash reflex, respiratory patterns, blood pressure, heart rate, and other vital sign changes have been observed by clinicians to assist in judging optimal insertion time. Nevertheless, these indicators show limitations in sensitivity and specificity. Given that rapid advances in anesthesia monitoring technologies have occurred, advanced tools such as the Bispectral Index (BIS), capnography, perfusion index (PI), and ultrasound measurement of vocal cord angles could demonstrate gradual application in assessing insertion timing for painless gastroscopy. Thus, relevant literature may be systematically reviewed in this article. Furthermore, the theoretical foundations and clinical applications of these monitoring indicators might be deeply analyzed. Therefore, the findings could provide clinicians with scientific, objective, and effective methods for evaluating insertion timing, which may enhance safety and efficacy of painless gastroscopy procedures.