Litholyme ® cost comparison with soda lime

Soda lime canisters should be recharged at least weekly to reduce the risk of carbon monoxide and compound A production 1, 2. Litholyme® (Allied Healthcare Products Inc., St. Louis, MO, USA) is a new carbon dioxide absorbent which eliminates the potential for production of these. We investigated whether there was any cost benefit in using Litholyme® compared to soda lime. After Institutional Review Board approval, we prospectively compared the cost of soda lime (Sofnolime®, Molecular Product Ltd., Boulder, CO, USA) and then Litholyme® over two sequential 4-week periods in 44 anaesthetic workstations (958 and 981 patients respectively) at our hospital. Soda lime canisters were recharged according to Anaesthesia Patient Safety Foundation recommendations 3 once a week routinely, if carbon dioxide rebreathing was detected by capnography (FiCO2 > 0.02), or if colour change in more than three-quarters of the canister indicated exhaustion. Litholyme® canisters were not changed unless rebreathing was detected. Results are presented in Table 3. Extrapolating from our results, our hospital might expect to save an estimated £6747 (€9109, US$10 236) per annum by switching from soda lime to Litholyme®. Vigilance should be maintained when using Litholyme®, however, with non-routine canister changes taking place when CO2 rebreathing is seen on capnography, in order to avoid hypercapnia 4.