The HEMC Model 2000 is a time controlled, volume-constant, pressure limited ventilator. Easy to learn and remember how to operate with only two controls to adjust ventilation and one to set an alarm. Easily exchangeable bellows and bellows housings minimizes the ventilators dead space contribution to the breathing system and provides better resolution of tidal volume deliveries. The change between housings can easily be made in 30 seconds. Parts in contact with the breathing system are easily accessible for cleaning and sterilization.
Features
Ascending bellows design. Ventilators with older and more traditional designs have bellows that fall during exhalation. There are very significant advantages associated with a system in which the bellows rises during exhalation. In the event that there is a leak or the patient becomes disconnected, anesthesia agents can only leak out. If a ventilator whose bellows descends during exhalation is used, leaks may lead to entrainment of driving gas during exhalation or air may be entrained into the circuit. The bellows will not appear to operate normally as it does with the older designs. The ascending bellows system does not have the potential of creating negative pressures in the respiratory system.
Wide range of settings. Inspiratory flow rates of 0-100 liter per minute (LPM) can be utilized over the full range of 6 to 40 breathes per minute (BPM) to the tidal volume limit of the bellows and housing in use. Using the interchangeable bellows and housings and an appropriate breathing system, tidal volumes ranging from 20 ml to 3 liters may be delivered for patients ranging from rabbits and ferrets to the not-so-small 500 lb. foal.
Economical use of supply gas is inherent in an electronically controlled ventilator. Older fluidic designs can consume as much or more driving gas to control the unit as is required to ventilate the patient. The HEMC Model 2000 is an electronically controlled time-cycled ventilator. It consumes no more supply gas that the ventilator rate, the minute volume consumption of the patient. In addition, the supply gas can be either oxygen, nitrogen, or clean dry air, a further economy.
Inspiratory hold mode. The breathing cycle may be paused at the end of the current or next inspiration for as long as the inspiratory hold button is held depressed. This feature is convenient when checking for breathing system leaks before each case or for leaky sutures in the chest cavity.
Alarms
Maximum Working Pressure Limit (MWPL) The MWPL feature allows the operator to set a maximum working pressure limit between 10 and 60 cm H2O. If the pressure sensed should ever reach the limit setting, the ventilator illuminates the red alarm light, sounds an audio alarm, terminates the inspiratory phase of the breathing cycle and permits exhalation. Note the INSPIRATORY HOLD feature is designed to not function when the MWPL setting is exceeded.
Low Breathing System Pressure (LO BSP) The LO BSP alarm is activated at the end of an inspiration in which there is not at least 5 cm H2O pressure sensed by the pressure transducer. This alarm is sometimes commonly referred to as a "disconnect" alarm; however, it should be understood that a patient disconnect is not always, nor, the only cause of low breathing system pressure. During the alarm condition, a red light is illuminated on the front panel and the sound of a rasp siren is heard. The alarm is automatically reset at the end of the next inspiratory phase in which there is a minimum of 7 cm H2O pressure sensed by the pressure transducer.
Low 50 PSI Supply Gas Alarm The LO SUPPLY GAS alarm ( HEMC PN 000a2425 ) is activated when the supply gas pressure drops below 35 psi. The sensor for this alarm is located downstream of the internal 40 micron filter and thus will also indicate a clogged filter condition. During an alarm condition, the red alarm light on the front panel is illuminated and a steady continuous tone is heard. This alarm automatically resets when the pressure increases above 35 psi.
Hallowell 2002
The Model 2002 Veterinary Anesthesia Ventilator is functionally equivalent to the Model 2000 with the following exception:
The Model 2002 contains an additional Volume Control - A 9 turn fine needle valve regulating inspiratory flow from ~ 0 to 20 lpm has been added. The output of this FINE control adds to the output of the original volume control making it now the COARSE control. The fine control is particularly useful in making small changes to any VOLUME adjustment or for adjusting for TV deliveries less than 200 ml.
Remember, the output of the two controls add together so if you are working at the very low end be sure to close the coarse control completely.
We also carry a complete line of accessories for Hallowell ventilators, from Bellows units to Housings, to Articulated shelves, hoses and "Y" connections. For further information, please call.
