Biomaterial Database

Isoflurane concentrations using uncompensated vaporisers within circle systems. 1998

S Brosnan, and B Royston, and D White

Department of Anaesthetics, Northwick Park Hospital, Harrow, London, UK.

In a series of studies designed to investigate the need for a temperature-compensated vaporiser for use in a circle system, we first studied temperature changes within and isoflurane concentration delivered by a Komesaroff vaporiser during bench tests using different gas flows. Agent temperature and vapour concentration decreased as predicted by the Antoine equation. Using the vaporiser within a circle system during clinical anaesthesia, we then studied 20 patients breathing spontaneously and a further 10 patients receiving controlled ventilation, measuring the temperature of the agent within the vaporiser and the concentration of agent inspired by a the patient. In clincial use with the frest gas flows of 1-3.min-1, the inspired agent concentration did not decrease despite the decrease in temperature of the liquid isoflurane in the vaporiser.

UI	MeSH Term	Description	Entries
D007385	Intermittent Positive-Pressure Ventilation	Application of positive pressure to the inspiratory phase when the patient has an artificial airway in place and is connected to a ventilator.	BIPAP Biphasic Intermittent Positive Airway Pressure,IPPV,Inspiratory Positive-Pressure Ventilation,Ventilation, Intermittent Positive-Pressure,Biphasic Intermittent Positive Airway Pressure,Inspiratory Positive Pressure Ventilation,Intermittent Positive Pressure Ventilation,Positive-Pressure Ventilation, Inspiratory,Positive-Pressure Ventilation, Intermittent,Ventilation, Inspiratory Positive-Pressure,Ventilation, Intermittent Positive Pressure
D007530	Isoflurane	A stable, non-explosive inhalation anesthetic, relatively free from significant side effects.
D009330	Nebulizers and Vaporizers	Devices that cause a liquid or solid to be converted into an aerosol (spray) or a vapor. It is used in drug administration by inhalation, humidification of ambient air, and in certain analytical instruments.	Atomizers,Inhalation Devices,Inhalators,Inhalers,Vaporizers,Nebulizers,Vaporizers and Nebulizers,Atomizer,Device, Inhalation,Devices, Inhalation,Inhalation Device,Inhalator,Inhaler,Nebulizer,Vaporizer
D004334	Drug Administration Schedule	Time schedule for administration of a drug in order to achieve optimum effectiveness and convenience.	Administration Schedule, Drug,Administration Schedules, Drug,Drug Administration Schedules,Schedule, Drug Administration,Schedules, Drug Administration
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000764	Anesthesia, Closed-Circuit	Inhalation anesthesia where the gases exhaled by the patient are rebreathed as some carbon dioxide is simultaneously removed and anesthetic gas and oxygen are added so that no anesthetic escapes into the room. Closed-circuit anesthesia is used especially with explosive anesthetics to prevent fires where electrical sparking from instruments is possible.	Anesthesia, Rebreathing,Closed-Circuit Anesthesia,Anesthesia, Closed Circuit,Anesthesias, Closed-Circuit,Anesthesias, Rebreathing,Closed Circuit Anesthesia,Closed-Circuit Anesthesias,Rebreathing Anesthesia,Rebreathing Anesthesias
D013696	Temperature	The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.	Temperatures
D018685	Anesthetics, Inhalation	Gases or volatile liquids that vary in the rate at which they induce anesthesia; potency; the degree of circulation, respiratory, or neuromuscular depression they produce; and analgesic effects. Inhalation anesthetics have advantages over intravenous agents in that the depth of anesthesia can be changed rapidly by altering the inhaled concentration. Because of their rapid elimination, any postoperative respiratory depression is of relatively short duration. (From AMA Drug Evaluations Annual, 1994, p173)	Inhalation Anesthetic,Inhalation Anesthetics,Anesthetic Gases,Anesthetic, Inhalation,Gases, Anesthetic
D019637	Orthopedic Procedures	Procedures used to treat and correct deformities, diseases, and injuries to the MUSCULOSKELETAL SYSTEM, its articulations, and associated structures.	Orthopedic Surgery,Surgery, Orthopedic,Orthopedic Rehabilitation Surgery,Orthopedic Surgical Procedures,Orthopedic Procedure,Orthopedic Rehabilitation Surgeries,Orthopedic Surgeries,Orthopedic Surgical Procedure,Procedure, Orthopedic,Procedure, Orthopedic Surgical,Procedures, Orthopedic,Procedures, Orthopedic Surgical,Rehabilitation Surgeries, Orthopedic,Rehabilitation Surgery, Orthopedic,Surgeries, Orthopedic,Surgeries, Orthopedic Rehabilitation,Surgery, Orthopedic Rehabilitation,Surgical Procedure, Orthopedic,Surgical Procedures, Orthopedic