PubMed Health⌕ Search

Biomedical subjects

J A Bushman

Publications and source records attributed to J A Bushman.

At least 19 recordsLinked to original sources
PubMed1997

A new method for the calibration of peak flow meters.

The objective of this paper is to assess the current methods for the calibration of peak flow meters and devise a method of producing a known flow with an inexpensive apparatus simple enough to be built from a set of dimensions. The methods currently available tend to be expensive and complex or impractical for routine use. The aim was that the wave form produced should approximate to a forced expiratory flow and be capable of being described in mathematical terms and be relatively inexpensive to produce. The resulting apparatus which has been built, produces a sine wave flow the peak of which can be set to any desired level and be determined to a high degree of accuracy. The apparatus can be built from a set of dimensions and is inexpensive. The apparatus is a primary and not a derived standard.

Calibration↗
PubMed1985

The laryngeal mask airway. Development and preliminary trials of a new type of airway.

A new form of airway has recently been described, which is introduced blindly into the hypopharynx to form a seal around the larynx, so permitting spontaneous or positive pressure ventilation without penetration of the larynx or oesophagus. The further development of this new airway is described and the results of 18 months' clinical experience are presented. The airway was used successfully in 118 patients, 17 of whom received controlled ventilation of their lungs. It was used in place of the facemask in routine anaesthesia, and was of particular value in ophthalmic, dental and ear, nose and throat procedures and where difficulties with the airway were expected. The incidence of sore throat and other problems was low. Experience of more than 500 cases suggests that the laryngeal mask airway may have a valuable rôle to play in all types of inhalational anaesthesia, while its proven value in some cases of difficult intubation indicates that it may contribute significantly to the safety of general anaesthesia.

Humans↗
PubMed1981

Closed-circuit halothane and enflurane using an in-circle Goldman vaporizer.

A closed-circle absorber system incorporating an in-circle Goldman vaporizer was used to administer halothane or enflurane in oxygen to adult patients. The attained inspired and end-tidal concentrations of volatile agent after a period of stabilization at each vaporizer setting were measured by mass spectrometry. During spontaneous respiration under halothane the ranges of inspired concentrations at settings 1, 11/2 and 2 were respectively 0.5-0.9%, 1.4-2.4% and 3.3-4.5%. corresponding inspired enflurane concentrations at the same settings were 0.8-1.4%, 1.9-2.8% and 3.7-5.0%. IPPV to 5% end-tidal carbon dioxide, although increasing the inspired concentrations slightly, produced considerable increases in end-tidal concentrations. Minimal pre-oxygenation was used to assess the problem of nitrogen accumulation within the circuit. The maximum nitrogen concentration was 56%.

Adult↗
PubMed1980

The anaesthetic machine--a study of function and design.

A study of the time and motion of the anaesthetists' routine activities was made using conventional equipment. Films of manual and visual movements were studied in detail and the expectations of certain consultant anaesthetists regarding apparatus were recorded. Models of apparatus were used to test their acceptability. A modular system appeared preferable to a work station or to adaptation of present designs. More work and the construction of prototypes are indicated if the anaesthetic machine is to be modernized.

Anesthesiology↗
PubMed1978

A new mouthpiece for the Wright peak flow meter.

When tested against artificially produced peak flows, the Wright peak flow meter is found to be an accurate instrument. A factor contributing to the variation seen when the meter is in clinical use in the design of the mouthpiece. This paper reports the results obtained using a new mouthpiece designed specifically to reduce this variation.

Adult↗
PubMed1977

Investigations of some aspects of atmospheric pollution by anaesthetic gases. I: Diffusion of halothane across plastic and rubber tubes.

Plastic and rubber tubing, of the types used frequently to convey anaesthetic gases to and from the patient, or anaesthetic waste gases out of the operating theatre, were assessed for their capacity to allow diffusion of halothane through the tube wall. The magnitude of this effect has been calculated in relation to pollution of the operating theatre atmosphere under different circumstances.

Air Pollution↗
PubMed1977

Investigations of some aspects of atmospheric pollution by anaesthetic gases. II: Aspects of adsorption and emission of halothane by different charcoals.

Four different charcoals have been assessed by exposure to halothane in air until 10, 100 and 500 p.p.m. (v/v) effluent was detectable. The pattern of halothane adsorption, its practical implications and the behaviour of different adsorbers has been demonstrated. The effluent concentration from a charcoal canister should be not more than 10 p.p.m. during the adsorption of 1.5% halothane from a gas flow of 5 litre/min. When 100 p.p.m. is detectable the charcoal should be considered exhausted.

Adsorption↗
PubMed1977

Closed circuit anaesthesia. A new approach.

A logical development of the closed circuit is described, from a basic resuscitation device, through various modifications, to a circle system incorporating an oxygen demand valve, adsorbers for both carbon dioxide and halothane, and some specific safety features. The behaviour of the circuits has been investigated in relation to elimination of nitrogen, concentrations of halothane and circuit leaks.

Anesthesia, Inhalation↗
PubMed1975

A new method for the measurement of carbon dioxide in the expired air.

A new method for measuring the concentration of carbon dioxide in the expired air, based on the variation of the gas in water, is described. The sensitivity of the basic instrument is such that it is able to measure parts per million but is non-linear above 1% carbon dioxide. The construction of a modified instrument to produce a linear output between 0-10% carbon dioxide is described.

Air↗