ZIB

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

A new paediatric metabolic monitor (1994)

Weyland, W. ; Weyland, A. ; Fritz, U. ; [et al.]

Springer

Intensive care medicine 20 (1994), S. 51-57

add to mindlist on the mindlist

Details

ISSN: 1432-1238

Keywords: Oxygen consumption ; Carbon dioxide ; Pediatric ; Indirect calorimetry ; Energy expenditure ; Mechanical ventilation

Source: Springer Online Journal Archives 1860-2000

Topics: Medicine

Notes: Abstract Objective A paediatric option for the measurement of $$\dot VO_2$$ and $$\dot VCO_2$$ (20 to 150 ml/min) has recently been introduced for the adult Deltatrac metabolic monitor (Datex Instrumentarium, Finland) to use in ventilated and spontaneously breathing children. This paper describes a laboratory validation of the paediatric option for ventilated children with regard to the influence of respiratory variables. Design Respiratory variables were varied within the following ranges: FIO2 0.21–0.8, $$\overline {FEO_2 }$$ (DFO2) 0.01–0.05, $$\overline {FECO_2 } 0.01 - 0.05,\dot V_E 300 - 6000ml/\min$$ , VT 8–300 ml, RR 10–50/min, Paw 10–60 mbar, relative humidity 10% and 60%, and resulted in 107 test situations. Setting Gas exchange was simulated by injection of nitrogen and CO2 at a RQ close to 1. Patients or participants Different situations of paediatric patients ventilated in controlled mode were simulated on a gas injection model. Interventions Respiratory and metabolic variables were varied independently to result in a range of 8 to 210 ml/min of $$\dot VO_2$$ and $$\dot VCO_2$$ . Measurements and results Reference measurements were carried out by mass spectrometry and wet gas spirometry. The mean $$\dot VCO_2$$ difference for all tests ranging from 20 ml/min to 210 ml/min was −2.4% (2SD=±12%). The respective $$\dot VO_2$$ difference was −3.2% (2SD=±23%). Measurement agreement for $$\dot VO_2$$ in neonatal respirator treatment (20–50 ml/min) compared to older children (50–210 ml/min) showed a mean difference of −3.9% (2SD=±26%) versus −2.8% (2SD=±20%). The respective differences for $$\dot VCO_2$$ were −7.1% (2SD=±7%) versus +0.4% (2SD=±10%). The mean difference for $$\dot VO_2$$ as well as $$\dot VCO_2$$ indicated a high systematic agreement of both methods. The variability (±2SD) in $$\dot VCO_2$$ measurement is acceptable for all applications. The overall variability in $$\dot VO_2$$ measurement (2SD=±23%) can be reduced by exclusion of all tests with a $${FECO_2 }$$ and DFO2 below 0.03. This results in a mean difference of −3.2% (2SD=±13.7%). Conclusion Within this limitation the paediatric measurement option seems to introduce a valuable method for clinical application in paediatric intensive care medicine.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF02425058

Permalink

Library	Location	Call Number	Volume/Issue/Year	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Phosphorescent spectral and decay studies of CaI - xSrxS:Ce solid solutions (1994)

Fritz, U. ; Ray, B. ; Viney, I. V. F. ; [et al.]

New York, NY [u.a.] : Wiley-Blackwell

Advanced Materials for Optics and Electronics 3 (1994), S. 283-288

add to mindlist on the mindlist

Details

ISSN: 1057-9257

Keywords: Phosphors ; Alkaline ; Earth sulphides ; Photoluminescence ; CaS ; SrS ; Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Electrical Engineering, Measurement and Control Technology , Physics

Notes: Ca1 - xSrxS Solid Solutions at 10 m/o intervals have been prepared by coprecipitation of sulphates from aqueous solution followed by reduction at 1000°C with hydrogen. Phosphorescence emission spectra have been determined for these solid solutions doped with 0.1 m/o cerium and show a blue shift with increasing strontium content from 2.46 to 2.59 eV. Hyperbolic phosphorescent decay curves were observed at both room and liquid nitrogen temperatures across the composition range and have been broken down into three exponential components by graphical and computer-programme-based methods. At room temperature trap depth values of 0.366, 0.316 and 0.282 eV with measured lifetimes of 1.9, 0.26 and 0.07 ms respectively were determined with little dependence on composition. At liquid nitrogen temperature shallower traps were observed at 0.103, 0.086 and 0.076 eV with respective decay times of 5, 0.4 and 0.09 ms having little sensitivity to changes in the host compostion. These traps are related to intrinsic defects, some of which may be surface in character. The blue shift in emission peak energy with the decrease in band gap from CaS to SrS is discussed.

Additional Material: 3 Ill.