The <i>in vitro</i> performance of carbon dioxide absorbents with and without strong alkali

Bedi, Amit; Gallagher, A. C.; Fee, J. P. H.; Murray, James

doi:10.1046/j.1365-2044.2001.01985.x

Cited by 6 publications

(5 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the latter study, however, values were reported after cumulative discontinuous clinical use, whereas our values resulted from a continuous use. For Amsorb ® Plus the utilisation time in our study was 17.1 h and for DrägerSorb ® Free it was 20.6 h. This contrasts with the reported time of up to 6 h to reach 0.5 kPa CO 2 using 1000 g Amsorb ® in vitro in a Julian ® cannister [12]. The longer utilisation time noticed by us with DrägerSorb ® Free would be a definite practical clinical advantage.…”

Section: Discussioncontrasting

confidence: 83%

“…It has been reported that the CO 2 absorption capacity of Amsorb ® concentrations is 10–15% less than that of soda lime [11,12] and even up to 50% less in another study [13]. During an in vivo study with low‐flow conditions, the CO 2 absorption capacity was only half that of soda lime and it was somewhat less using a compact 750‐ml ADU ventilator cannister than using a 1360 ml Aestiva 3000 ® cannister (Datex Ohmeda, Helsinki, Finland) [14].…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Production of compound A and carbon monoxide in circle systems: an in vitro comparison of two carbon dioxide absorbents*

et al. 2004

View full text Add to dashboard Cite

Two new generation carbon dioxide absorbents, DrägerSorbÒ Free and Amsorb Ò Plus, were studied in vitro for formation of compound A or carbon monoxide, during minimal gas flow (500 ml.min )1 ) with sevoflurane or desflurane. Compound A was assessed by gas chromatography ⁄ mass spectrometry and carbon monoxide with continuous infrared spectrometry. Fresh and dehydrated absorbents were studied. Mean (SD) time till exhaustion (inspiratory carbon dioxide concentration ‡ 1 kPa) with fresh absorbents was longer with DrägerSorb Ò Free (1233 (55) min) than with Amsorb Ò Plus (1025 (55) min; p < 0.01). For both absorbents, values of compound A were < 1 ppm and therefore below clinically significant levels, but were up to 0.25 ppm higher with DrägerSorb Ò Free than with Amsorb Ò Plus. Using dehydrated absorbents, values of compound A were about 50% lower than with fresh absorbents and were identical for DrägerSorb Ò Free and Amsorb Ò Plus. With dehydrated absorbents, no detectable carbon monoxide was found with desflurane.

show abstract

Section: Discussioncontrasting

confidence: 83%

Section: Discussionmentioning

confidence: 99%

Production of compound A and carbon monoxide in circle systems: an in vitro comparison of two carbon dioxide absorbents*

et al. 2004

View full text Add to dashboard Cite

show abstract

“…The most likely reason is because different canister designs were used in each period: 600g in the manual phase and 800g in the Et control phase. CO 2 absorbents in larger canisters have consistently been shown to have higher absorptive capacities 25,26 . This is because an absorbent is at its most efficient when a patient's tidal volume is equal to the void space (the air between the granules) within the canister 27 .…”

Section: Discussionmentioning

confidence: 99%

Financial and Environmental Costs of Manual versus Automated Control of End-Tidal Gas Concentrations

Tay

Weinberg

Peyton

et al. 2013

Anaesth Intensive Care

View full text Add to dashboard Cite

Emerging technologies that reduce the economic and environmental costs of anaesthesia have had limited assessment. We hypothesised that automated control of end-tidal gases, a new feature in anaesthesia machines, will consistently reduce volatile agent consumption cost and greenhouse gas emissions. As part of the planned replacement of anaesthesia machines in a tertiary hospital, we performed a prospective before and after study comparing the cost and greenhouse gas emissions of isoflurane, sevoflurane and desflurane when using manual versus automated control of end-tidal gases. We analysed 3675 general anaesthesia cases with inhalational agents: 1865 using manual control and 1810 using automated control. Volatile agent cost was $18.87/hour using manual control and $13.82/hour using automated control: mean decrease $5.05/hour (95% confidence interval: $0.88-9.22/hour, P=0.0243). The 100-year global warming potential decreased from 23.2 kg/hour of carbon dioxide equivalents to 13.0 kg/hour: mean decrease 10.2 kg/hour (95% confidence interval: 2.7-17.7 kg/hour, P=0.0179). Automated control reduced costs by 27%. Greenhouse gas emissions decreased by 44%, a greater than expected decrease facilitated by a proportional reduction in desflurane use. Automated control of end-tidal gases increases participation in low-flow anaesthesia with economic and environmental benefits.

show abstract

“…The monovalent hydroxides are more reactive than the divalent Ca(OH) 2 . 10 Where crystals have been allowed to dry out, such as leaving the gas flowing through the canister overnight, these highly reactive monovalent hydroxides can also produce significant amounts of carbon monoxide and even formaldehyde, 11,12 which are toxic to subsequent patients. As well as absorbing CO 2 , the absorbents also tend to absorb volatile anaesthetic agents themselves; 13 this is generally acceptable, though wasteful, but certain agents can produce neurological toxins, for example, trichloroethylene (no longer available) reacting with soda lime-produced dichloroacetylene gas (phosgene).…”

Section: Anaesthetic Circle Systemsmentioning

confidence: 99%

Circle (CO₂ reabsorbing) breathing systems: Human applications

Magee¹

2017

Proc Inst Mech Eng H

View full text Add to dashboard Cite

Artificial breathing systems to help humans survive extreme environments are used over a range of ambient pressures, using various gases of different volumetric concentrations. These activities include anaesthesia and intensive care activity, high-altitude mountaineering, firefighting, aerospace extravehicular space activity and underwater diving operations. A circle breathing system is one in which the exhaled carbon dioxide is absorbed by an alkali substance and the remaining unused gases are recirculated, usually for the sake of economy and environment. This allows the flow of the fresh gas to be considerably reduced, thereby saving on fresh-gas supply. Circle systems are often used in the circumstances cited above, although not always at low fresh-gas flows. The circle system used in anaesthesia and intensive care has the least engineering demands made on it, although it is used on patients who are highly vulnerable; it usually provides a mixture of air and oxygen, and perhaps a breathable anaesthetic gas, all at sea-level pressure. Mountaineering and firefighting applications involve an extreme earthbound environment, with the user undergoing extreme physical work. The astronaut's spacesuit and life support system contains a high-flow circle system, the breathing gases themselves pressurising the suit as well as providing respiratory life support and thermal comfort; the gas provided is pure oxygen at about a third of sea-level atmosphere. There are numerous varieties of breathing systems for diving, including a circle system, often for clandestine naval activity; the gases used are a combination of oxygen, nitrogen and helium, to minimise the possibility of decompression sickness, nitrogen narcosis and oxygen toxicity and must be provided at a varying pressure and concentration appropriate to depth.

show abstract

The in vitro performance of carbon dioxide absorbents with and without strong alkali

Cited by 6 publications

References 22 publications

Production of compound A and carbon monoxide in circle systems: an in vitro comparison of two carbon dioxide absorbents*

Production of compound A and carbon monoxide in circle systems: an in vitro comparison of two carbon dioxide absorbents*

Financial and Environmental Costs of Manual versus Automated Control of End-Tidal Gas Concentrations

Circle (CO₂ reabsorbing) breathing systems: Human applications

Contact Info

Product

Resources

About

The in vitro performance of carbon dioxide absorbents with and without strong alkali

Cited by 6 publications

References 22 publications

Production of compound A and carbon monoxide in circle systems: an in vitro comparison of two carbon dioxide absorbents*

Production of compound A and carbon monoxide in circle systems: an in vitro comparison of two carbon dioxide absorbents*

Financial and Environmental Costs of Manual versus Automated Control of End-Tidal Gas Concentrations

Circle (CO2 reabsorbing) breathing systems: Human applications

Contact Info

Product

Resources

About

Circle (CO₂ reabsorbing) breathing systems: Human applications