Nociception Along With Interventional Bronchoscopy: Analyzed With Analgesia Nociception Index.

Background: Anesthesia for interventional bronchoscopy (IB) presents significant challenges, primarily due to unpredictable responses such as coughing, airway spasms, and desaturation, even with monitored anesthetic care. However, the nociception inducing such responses and the impact of adding topical anesthesia (TA) have rarely been investigated. This study aims to map the timing and intensity of nociception, determine TA onset, and clarify TA's role in blocking nociception with subsequent IB procedures.

Methods: Analgesia nociception index (ANI) and mean arterial blood pressure (MBP) were collected in patients undergoing IB procedures with bispectral index (BIS)-controlled intravenous anesthesia. Data were compared and analyzed along with various stages: anesthetic induction with iGel insertion, fibro-optic bronchoscopy (FOB) insertion, and applying TA with the spray-as-you-go (SAYGO) method using xylocaine, up to 30 minutes with subsequent IB procedures.

Results: Data from 82 patients were analyzed. Under BIS-controlled anesthesia, iGel insertion decreased ANI significantly (P < 0.001). Following stabilization, ANI decreased significantly with SAYGO (P < 0.001), returned toward baseline within 5 minutes, and remained stably higher than baseline for up to 30 minutes. The changes on MBP were similar to those of ANI. No significant correlations were observed between BIS levels and ANI.

Conclusions: ANI offers a valuable perspective on nociception, serves as a helpful reference for precise anesthetic management for IB. The key action, such as an ultrashort-acting anesthetic just before FOB insertion to block nociception from the establishment of TA without prolonged effect, is suggested for smooth, subsequent IB procedures.