The BIA method ( BioImpedence Analysis), either single frequency or multifrequency (MFBIA),
is today commonly used clinical nutrition for the estimation of body composition parameters
like Total Body water, intra and extra cellular water, fat free mass and other.
The Human IM Plus 2 impedance analyzer performs all the basic functions for a complete BIA analisys:
- AC current generator
- voltage signals acquisition
- impedance calculation
- formulas application
- patient data visualization and storage
The Human IM Plus 2 can operate in stand alone mode ( LCD and data entry keyboard on the instrument front panel)
or PC remote controlled mode; in remote controlled mode the PC is connected via an optical fiber serial communication cable.
The instrument electronic board integrates all the up to date technical solutions concerning the treatment
of bioelectrical signals, wich usually show poor signal to noise ratio.
Its main features are:
- System design and building compliant with Medical electrical equipment international standards.
- 16 bit microprocessor system with field level firmware upgrade capability via optical serial interface.
- Management and storage of up to 20 patient data files and up to 10 body composition estimation formulas.
- Direct digital synteshis of the AC current signal injected; this feature gives stability over time and
minimum distortion, also reflected in the quality of impedance measurement.
- Voltage input circuitry compliant with state of the art professional laboratory instrumentation:
integrated differential amplifier with high input impedance and commom mode signals rejection on the whole frequency range;
direct analog to digital conversion that gives input waveform analysis capability and error detection
( i.e: bad electrode connection, too much noise etc.)
- Parasitic cable capacitance reduction circuitry. The natural capacitive coupling between probe cables brings
to unprecise measurement at frequencies above 100 Khz; the circuitry employed reduces the coupling effect
so that it is not necessary to use software compensation routines that normally works well only on simplified
- Measuring menů: impedance and phase angle, resistance and reactance; 12 frequencies from 5Khz to 250Khz,
manual or automatic increment. Total Body ( 4 probes) or Segmental (6 probes) measurement.
- Internal rechargeable lead acid battery.
- Built in instrument self diagnostic routines with high stability internal reference impedance.
- Optical fiber serial communication port; the instrument can be connected to a remote PC while ensuring
galvanic isolation between the patient and the earth.
- Stand by (low consumption) and auto switch-off capability.
- Autonomy: more than 24h in full operative mode.
- Measuring range: 0 to 2000 ohm, 5 to 250Khz
- Precision (impedance, 499 ohm sample): ±0,2 %
- Resolution (impedance): 1 ohm
- Precision (phase angle 499 ohm//1nF RC network) ± 0,5 degrees
- Resolution (phase angle) 0,1 degrees
- Total Body probe cable (4 electrodes)
- Segmental Probe cable ( 6 electrodes)
- Battery charger
- Optical fiber to RS232C converter
- Optical fiber to USB converter