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The SFB3 is portable, easy to use and robust. A 12 volt rechargeable battery supplies power. The machine is easily operated by using touch pads on the front panel.
During bioimpedance measurement, skin contact electrodes are placed at specific sites of study. We supply actively shielded leads which use signal multiplexing. Our leads weigh less than 100 grams, making them ideal for use in studies with neonates.
When single frequency estimation of bioimpedance is chosen on the SFB3 an immediate readout of impedance, resistance and reactance is given. For 50kHz a choice of algorithms available in the software packages gives a readout of total body water, extracellular body water and fat free mass.
Multiple frequency estimation of bioimpedance parameters over the chosen frequency range requires an IBM-compatible PC. Software for mass data storage and analysis after patient assessment is supplied. The SFB3 will store between 16 and 246 data records which can be analysed on a DOS computer or notebook fitted with a serial port. The software provides estimates of impedance, resistance, reactance and phase angle extrapolated to zero and infinite frequency using Cole-Cole analysis (2). In addition the characteristic frequency for the subject is determined as well as mean cell membrane capacitance. These estimates are then used in new algorithms to give body water and fat free mass.
In studies by Cornish (3,4) significant improvement was found in the prediction of body water using multiple frequency bioelectrical impedance and phase analysis. The method also provides values for extra and intracellular water compartments.
The SFB3 can be used in body composition studies in children and adults, nutritional research and where hydration states require monitoring eg. renal dialysis, or where disturbance of body water compartments occurs eg. lymphoedema (5).
1 Schulz, L.O. (1993) Methods of body composition analysis, Trends Endocrinol. Metab., 4:318-322.
2 Cole, K.S. (1968) Membranes, ions and impulses: A chapter of classical biophysics, UCLA Press, Los Angeles CA.
3 Cornish, B.A.H. et al (1992) Measurement of extracellular and total body water of rats using multiple frequency bioelectrical impedance analysis, Nutrition Research,12:657-666.
4 Cornish, B.A.H. et al (1994) Alteration of the Extracellular and Total Body Water Volumes Measured by Multiple Frequency Bioelectrical Impedance Analysis, (MFBIA) Nutrition Research, 14:717-727.
5 Ward, L. et al (1992) Multi-frequency bioelectrical impedance augments the diagnosis and management of lymphoedema in post-mastectomy patients, Eur. J. Clin. Invest., 22:751-754.
Dimensions: 246 x 286 x 59mm
Weight: 2.2kg
Battery charging : 12V DC, 1A
Operating temperature range: 10-40°C
Frequency Scan
Range: 4 to 1024 kHz
(in 31, 62, 124, 248 or 496 user selected logarithmically spaced steps or a single user selected frequency)
Resolution: <0.2%
Scan speed: 7 seconds
Impedance
Range: 10 to 2000 Ohm
Resolution: <0.1 Ohm
Accuracy: ±0.5%
Phase
Range: -5° to 50°
Resolution: <0.1°
Accuracy: ±0.5%
Display:
Frequency, impedance, phase angle
Electrodes
Lead length: 1.75m - extensions available from manufacturer
(Electrode arrangement active tetrapolar)
Electrode current range: 190uA (Leads are light weight and incorporate active shielding)
Current stability: 0.5%
Input impedance : >10*7 Ohm
Computer Requirements
IBM or compatible (640K minimum)
MS-DOS operating system plus mouse
Computer interface: 9 pin serial (Incorporates opto-isolators)
Dot matrix parallel printer (optional)
These specifications are current but subject to change.
For further information, contact:
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Telephone: + 61-7-3423-1777 Postal address: |
