2) H2CO3 + 2NaOH Na2CO3 + 2H2O
3) Na2CO3 + Ca(OH)2 CaCO3 + 2NaOH
4) H2CO3 + Ca(OH)2 CaCO3 + 2H2O
- Allows rebreathing, conserves gases and volatile agents, decreases theatre pollution & avoids carbon dioxide rebreathing.
- CO2 in solution (carbonic acid) reacts with sodium hydroxide to form sodium carbonate (water soluble salt)
The equations above are based on the canister containing CALCIUM HYDROXIDE & SODIUM HYDROXIDE
Data assembled from APSF Newsl 2005;2:25; Anesth Analg 2001;93:221; Anesthesiology 2001; 95:1205; Anesth Analg. 2000;91:220
Dr. David Lyness@Gas_Craic
Removal from the Anaesthetic or Mapleson C Circuit & Compound A
- Sevoflurane is unstable in soda lime, producing Compound A (lethal at 130-340 ppm, or renal injury at 25-50 ppm in rats)
- Compound A concentrations of 25-50 ppm are easily achievable in normal clinical practice.
- Lithium-containing (Litholyme) or lithium-based (Spiralith) absorbents
- Absorbents which lack activators