Which anesthetic agent is associated with the highest level of carbon monoxide formation?

Desflurane undergoes degradation to carbon monoxide in the presence of strong bases in dry CO2 absorbents ( like desiccated soda lime). The propensity for CO production correlates with anesthetic concentration in the breathing circuit (Desflurane > Isoflurane > enflurane). Though Sevoflurane, methoxyflurane, and halothane also degrade in the presence of strong bases, they do not produce CO. CO production is predominantly seen with absorbents that contain barium hydroxide and when the water content of soda lime or Baralyme falls below 1.4% and 5%. Amsorb is a CO2 absorbent which is more ine than soda lime and baralyme and so associated with lesser degradation of anesthetics and so less carbon monoxide production.