Prediction of Immediate Postoperative Pain Using Analgesia/Nociception Index (ANI)

Prediction of Immediate Postoperative Pain Using Analgesia/Nociception Index (ANI): an Observational Study

The aim of this study is to evaluate the performance of Analgesia/Nociception Index (ANI) measured at the end of surgery for the prediction of immediate postoperative pain in postoperative care unit in adult patients undergoing general anesthesia.

Assessment of the performance of ANI to predict immediate postoperative pain on a 0-10 numerical rating scale (NRS) >3 by building a receiver operating characteristic curve.

Inclusion Criteria:

• adult
• ear-nose-throat or orthopedic surgical procedures
• halogenated and remifentanil-based general anesthesia

Exclusion Criteria:

• age <18 yrs or >75 yrs
• arrythmia
• administration of anticholinergic drugs or neuromuscular blockade reversal in the 20 previous minutes
• psychiatric diseases
• autonomic nervous system disorders (epilepsy)
• inability to understand the verbal rating pain scale