Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CALORIMETRY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 919 records · Page 51Linked to original sources

Indirect calorimetry in chair-adapted primates.

This paper describes the construction of an indirect calorimeter for measurement of respiratory gas exchange in the chaired primate. Preliminary determinations of energy expenditure and respiratory quotient in five animals under a variety of dietary conditions suggest that this system will prove useful in the laboratory study of primate nutrition, energy metabolism, and cardiorespiratory physiology. Other possible uses and limitations are discussed.

Adaptation, Physiological↗

[Indirect calorimetry in mechanically ventilated children. 3. Clinical use of a new measurement procedure].

After the new device for measurement of oxygen uptake (VO2) and carbon dioxide elimination (VCO2) was tested in a pneumatic lung model, we investigated its clinical practicability. First the level of VO2 and VCO2 in the early postoperative phase was determined. Secondly we examined alterations in gasexchange caused by various intensive care activities. Whereby main concern was the change from mechanical ventilation to spontaneous CPAP-breathing. Ten children undergoing cardiac surgery (age: 10 days to 10 years) were included in the study. Three children were primarily investigated on the CPAP-system. Data from another six were collected under controlled ventilation as well as under spontaneous CPAP-breathing. One child had to be ventilated for a longer time (greater than 24 h). The change from mechanical ventilation to spontaneous breathing was accompanied with a temporary increase of VO2 and VCO2. As expected, all stressful factors like tracheal suction, pain or anxiety increased these two variables. Also some drugs showed remarkable changes. While marked increases under Normastigmine, Naloxone, and Dopamine could be observed, gas exchange was decreased under Morphine. However, heart rate showed no good correlation with VO2. We conclude that the developed prototype is a reliable device for measuring VO2 and VCO2. Our results suggest that spontaneous CPAP-breathing is not always accompanied with increased gas exchange. If there is an increased gas exchange, it may refer to transient changes during the adaption phase. Therefore, a continuous monitoring of VO2 and VCO2 over a longer period of time is necessary. Consequently the first phase after changing ventilatory support has to be viewed carefully. The heart rate in children, undergone cardiac surgery, is not a good predictor for determination of VO2 and thus for energy expenditure. This device allows to quantify accurately oxygen consumption and carbon dioxide elimination in ventilated children. Furthermore, alterations in metabolism and cardiopulmonary variables caused by intensive care and therapeutic interventions can be examined continuously. It seems to be a valuable tool for metabolic and cardiopulmonary monitoring in critically ill children.

Calorimetry↗

Interface design for indirect calorimetry in children with cerebral palsy.

The purpose of this study was to design, construct, and validate an alternative subject/instrument interface to collect metabolic data for individuals who, because of impairment, are unable to use a mouthpiece. An industrial designer directed the development of an interface design which would facilitate subject acceptance. A total of 13 subjects (eight children with cerebral palsy and five nonneurologically impaired) participated in the validation study. Metabolic data were collected at rest and during three levels of exercise, using both the traditional mouthpiece and the interface designed for this study. Exercise intensities were matched for both experimental conditions. Subjects exercised using an electrically braked ergometer configured for arm pedaling. A modification in a Beckman Metabolic Cart allowed for the collection of values with a standard mouthpiece and low-flow interface. Validity of the interface was evaluated using a concurrent, criterion procedure. Correlations of mouthpiece vs interface data during rest and across each exercise level for oxygen consumption were high (r = 0.94 to 0.84; p less than 0.05). Similar results were obtained for carbon dioxide production (r = 0.92 to 0.85; p less than 0.05).

Adolescent↗