AF ablation with sedation
The feasibility and safety of deep sedation during AF ablation has been previously reported14-15. However, intravenous sedation with an anesthetic agent such as propofol causes respiratory suppression due to upper airway collapse, and the anesthetic depth is associated with the respiratory status16.
As the sedation depth, anesthetic dosing was adjusted to maintain the BIS value within a target range of 50-70 and actual average BIS value before the ASV support was approximately 68, suggesting the sedation depth was nearly moderate sedation12-13. In patients under the moderate sedation depth, it is generally considered that no interventions are required to maintain a patent airway and spontaneous ventilation is adequate17. However, the present study revealed that the 73% of the sedated patients had negative lowest LAP value before the ASV support. That suggested that the LAP could become negative even in patients under moderate sedation. During the procedure, the sedation level often resulted in a deeper sedation level than initially intended. Therefore, the fact that the risk of air intrusion might change depending on the sedation continuum should be noted.
Additionally, the introduction and maintenance of the sedation was performed with an intravenous propofol administration. For an intravenous anesthetic agent during AF ablation, propofol, midazolam, dexmedetomidine are commonly used. Out of those anesthetic agents, dexmedetomidine has a relatively less propensity for the induction of an upper air way collapse in comparison to propofol 12. If dexmedetomidine is administered for the anesthesia, the prevalence of a negative LAP under sedation could be smaller.