Airway Heat and Humidity during Endotracheal Intubation: I. Inspiration of Arid Gases via a Non-Rebreathing Circuit

Shanks, Colin A.; Sara, Charles

doi:10.1177/0310057x7300100303

Cited by 10 publications

(3 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It appears from the table that the HME reduces the heat loss by about 31.5 kJ/h if the ventilation is 10 I/min. For comparison, the respiratory heat loss during normal breathing has been estimated at approximately 33.5 kJ/h, which equals about 10% of the body's total heat losses (13,14). Table 3 Calculated approximate heat and moisture losses for intubated patients.…”

Section: Core Temumentioning

confidence: 99%

Heat and moisture exchangers and the body temperature: a peroperative study

Eckerbom

Lindholm

1990

Acta Anaesthesiol Scand

View full text Add to dashboard Cite

The importance of conditioning the inhaled gas for maintaining the body temperature during artificial respiration was investigated. The mean body temperature (MBT) was deduced from readings from five measuring sites, four of which were situated at the skin and the fifth in the rectum. Temperature recordings were made every 15th min. Twenty patients were admitted to the study. In 10 patients a heat and moisture exchanger was used (the HME group), and the other 10 were ventilated without an HME (the control group). The patients were normoventilated, and a non-rebreathing system was used. All operations were made in the ENT-region of the body. Great care was taken to avoid variation of external factors that may affect the MBT. We found that the MBT decreased 0.2 degrees C/h less in the HME group than in the control group. If corrections were made for differences in amounts of fluids given and age factors, a difference in heat loss of 41.6 kJ/h between the two groups could be derived from this figure. This difference was statistically significant. Our finding correlated fairly well with a predicted reduction of heat loss of 26.0 kJ/h for the type of HME used. A certain margin of error seemed to be inevitable in measuring body temperatures, and the reason for this is discussed. Our results support the fact that the investigation is adequately designed, and that the heat conserved with an HME is rather low.

show abstract

Section: Core Temumentioning

confidence: 99%

Heat and moisture exchangers and the body temperature: a peroperative study

Eckerbom

Lindholm

1990

Acta Anaesthesiol Scand

View full text Add to dashboard Cite

show abstract

“…A model lung ( Figure 2) was used to represent the patient, and a heavily lagged endotracheal tube was placed in the mock trachea (Shanks and Sara 1973). The catheter mount connected to the tube had thermocouple probes (TRA-1, Elektrolaboratoriet, Copenhagen) placed within its lumen to measure temperatures and humidities at the junction with an Ambu E valve.…”

Section: Laboratory Studies'mentioning

confidence: 99%

“…Further thermocouples werc used to measure temperature and humidity at the delivery point of the humidifier, and at the patient end of the delivery tube. End-phasic humidities were obtained by psychrometry, the second of the paired thermocouples being adapted to provide "wet bulb" temperatures (Shanks and Sara 1973). Dry anaesthetic gases flowed into either of the two types of water-bath units.…”

Section: Laboratory Studies'mentioning

confidence: 99%

A Comparison of Two Heated Water-Bath Humidifiers

Shanks

Gibbs

1975

Anaesth Intensive Care

View full text Add to dashboard Cite

The performance of two heated water-bath humidifiers was examined in terms of airway temperatures and humidities. These were the simple heated tank (Marshal! and Spalding, 1953) and the Fisher and Paykel No. 328 (Spence and Melville, 1972), both of which had the potential to deliver gases at temperatures above 40°C, and with a moisture content in excess of 50 mg/litre. The major advantage of the No. 328 was its heating wire in the delivery tube. This lessened or prevented condensation within the tube, and allowed the water bath to be maintained at lower temperatures. Independent heat controls for the water bath and the delivery tubing allow precision of humidities in the gases provided for inspiration through an artificial airway. When condensation is prevented, the temperature of the saturated gases leaving the humidifier limits the absohtte humidity supplied. Monitoring and adjustment of airway temperature of the patient then allows selection of temperature and relative h1Jmidity in the inspired gas.

show abstract

Humidification and Loss of Body Heat During Anaesthesia I: Quantification and Correlation in the Dog

Shanks

1974

British Journal of Anaesthesia

View full text Add to dashboard Cite

Changes in temperature and body heat were measured in 30 patients. Despite the warming of most fluids given intravenously, all the patients ventilated with dry anaesthetic gases became cooler, with an average heat loss of 12.4 kilocalories per hour. In a group to whom the gases were delivered saturated at body temperature, the average hourly loss was 1.5 kilocalories. This difference is in agreement with the effects calculated from respiratory heat exchange, and indicates that heated humidification can help to limit or prevent the development of hypothermia in anaesthetized adults.

show abstract

Airway Heat and Humidity during Endotracheal Intubation: I. Inspiration of Arid Gases via a Non-Rebreathing Circuit

Cited by 10 publications

References 9 publications

Heat and moisture exchangers and the body temperature: a peroperative study

Heat and moisture exchangers and the body temperature: a peroperative study

A Comparison of Two Heated Water-Bath Humidifiers

Humidification and Loss of Body Heat During Anaesthesia I: Quantification and Correlation in the Dog

Contact Info

Product

Resources

About