摘要:
A Doppler blood flow system and method in which an ultrasonic wave is reflected off of red blood cells in blood flowing in tubing. The reflected ultrasonic wave is digitally processed in the frequency domain. The flow rate of the blood is directly related to the average frequency of the Doppler signal. Because the Doppler blood flow system calculates flow rate solely on the basis of frequency, a special case exists at zero rate of flow where the received signal is not a valid Doppler flow signal, but rather purely noise. The noise at zero flow rate is random and will not have an average frequency which is unique to zero flow. The Doppler blood flow system and method must invoke a special case determination of when a zero flow condition exists in order to accurately provide a blood flow rate. The system utilizes a method of determining the rate of flow of a fluid containing particles flowing through a tube. An ultrasonic signal is transmitted through the tube at an oblique angle thereto. The ultrasonic signal which has been reflected off of the particles contained in the fluid is received as a received ultrasonic signal. The rate of flow of the fluid is calculated from the received ultrasonic signal using Doppler techniques. Whether the special case of the value of the rate of flow being equal to zero exists is determined and the value of the rate of flow is set equal to zero for the special case.
摘要:
A Doppler blood flow system and method in which an ultrasonic wave is reflected off of red blood cells in blood flowing in tubing. The reflected ultrasonic wave is digitally processed in the frequency domain. The flow rate of the blood is directly related to the average frequency of the Doppler signal. The typical Doppler signal is not a single frequency representing a single flow rate but is really an entire range of frequencies in which certain frequencies predominate which are indicated by increased amplitude of the signal when plotted in the frequency domain. The typical Doppler signal may actually have two "humps", one at a higher frequency which represents the actual information bearing content of the signal related to flow rate and one at a lower frequency which is caused by vibrations in the blood tubing system itself and could be caused by motor noise from the blood pump. Since the flow rate is related to average frequency of the information bearing portion of the typical Doppler signal, the low frequency "hump" must be taken out of the Doppler signal in order to obtain an accurate flow rate.
摘要:
An adapter pod for use in a medical perfusion system having a data communications network with a plurality of connection points each having a substantially identical network connector. The adapter pod includes a housing and a common connector associated with the housing which is adapted to be connected to one of the network connectors and which has a connector configuration. A device connector is also associated with the housing, is adapted to be connected to a perfusion device, and has a configuration different than the connector configuration of the common connector. A controller is disposed within the housing and is adapted to generate messages in the form of digital data packets.
摘要:
A medical perfusion system for use in connection with the medical treatment of a patient is provided with a first type of perfusion device in the form of a blood pump adapted to pump blood through a fluid conduit connected to the patient and a second type of perfusion device in the form of a sensing device adapted to sense a condition and generate a sensing signal relating to the condition. The perfusion system also includes an electrical power network having an electrical power line, means for selectively connecting the perfusion devices to the electrical power network, and a controller with an input device for accepting control commands from an operator. The perfusion system could also include a control device, such as a pump, a plurality of sensing devices, and means for specifying the sensing device that the control device should be accept feedback from.
摘要:
A medical perfusion system for use in connection with the medical treatment of a patient is provided with a first type of perfusion device in the form of a blood pump adapted to pump blood through a fluid conduit connected to the patient, a second type of perfusion device in the form of a sensor adapted to sense a condition relating to the pumping of blood through the fluid conduit and to generate a sensing signal relating to the condition, and a data communications network for operatively interconnecting the perfusion devices. The perfusion system also includes means for transmitting messages in the form of digital data packets among the perfusion devices over the data communications network and a controller operatively coupled to the perfusion devices via the data communications network, the controller having an input device for accepting pump control commands relating to the blood pump from an operator.