The prediction probabilities for emergence from sevoflurane anesthesia in children: A comparison of the perfusion index and the bispectral index.

BACKGROUND: Predicting recovery of consciousness is one of the most essential functions of anesthesia depth monitors in anesthesia practice. Perfusion index and bispectral index are 2 indicators of the anesthesia depth monitoring with different working principles. The progression of the anesthesia emergence stages reflected by those monitors has not been well understood, especially in pediatric patients. The goals of this study were to compare the prediction probabilities of perfusion index and bispectral index in predicting awakening and in differentiating the different levels of arousal during emergence after sevoflurane anesthesia in children undergoing open inguinal hernia repairs.

METHODS: Forty-five patients, aged 1 to 5 years, ASA Status I or II and scheduled for elective open inguinal hernia repairs under general anesthesia were enrolled. The perfusion index and bispectral index were monitored simultaneously during anesthesia recovery. The University of Michigan Sedation Scale was applied to evaluate the clinical arousal levels during emergence. The prediction probability was used to assess the performance of perfusion index and bispectral index in predicting awakening and distinguishing different levels of arousal corresponding to the University of Michigan Sedation Scale during recovery.

RESULTS: The prediction probability of perfusion index (PkPI-Awakening  = .81, 95% CI 0.73-0.89) in differentiating full consciousness from unconsciousness during recovery was comparable to that of bispectral index (PkBIS- Awakening  = .86, 95% CI 0.79-0.92) (P = .47). The prediction probability for perfusion index (PkPI-UMSS  = .61, 95% CI 0.55-0.73) and bispectral index (PkBIS-UMSS  = .64, 95% CI 0.53-0.69) had similar performance in distinguishing different University of Michigan Sedation Scale levels.

CONCLUSION: Both the perfusion index and bispectral index performed comparably well in predicting awakening and different arousal levels when emerging from sevoflurane anesthesia in children.