Abstract: A method and apparatus for operating a ventilator to control the fraction of pressure inspired oxygen (FiO2) to a patient that includes: providing a ventilator controller that includes a software algorithm, a pulse oximeter and a FiO2 flow rate controller; measuring the pulse oximetry of the patient and computing an average pulse oximetry value over a time period; selecting a first, second and third pulse oximetry levels as set points for the ventilator controller; selecting an update time interval; decreasing the FiO2 flow rate by a first incremental amount when the average pulse oximetry value is greater than the first level; increasing the FiO2 flow rate by a second incremental amount when the average pulse oximetry value is less than the second level; increasing the FiO2 flow rate to the maximum and initiating an alarm condition when the average pulse oximetry value is less than the third level.

Abstract: A method and apparatus for operating a ventilator to control the fraction of pressure inspired oxygen (FiO2) to a patient that includes: providing a ventilator controller that includes a software algorithm, a pulse oximeter and a FiO2 flow rate controller; measuring the pulse oximetry of the patient and computing an average pulse oximetry value over a time period; selecting a first, second and third pulse oximetry levels as set points for the ventilator controller; selecting an update time interval; decreasing the FiO2 flow rate by a first incremental amount when the average pulse oximetry value is greater than the first level; increasing the FiO2 flow rate by a second incremental amount when the average pulse oximetry value is less than the second level; increasing the FiO2 flow rate to the maximum and initiating an alarm condition when the average pulse oximetry value is less than the third level.

Abstract: A respiratory tract differential-pressure flow sensor, including a tube having a distal end that is insertable into a respiratory tract, an interfering body disposed within the tube proximal to the distal end and having a first edge facing one end of the tube and a second edge facing away from the end, the interfering body extending across the diameter of the tube, a first pressure sensing port operative to sense an air pressure, the first port being disposed in the first edge not abutting the wall of the tube, and a second pressure sensing port operative to sense an air pressure, the second port being disposed in the second edge not abutting the wall of the tube, where either of the edges is inclined inwardly towards the axis of the interfering body extending across the diameter of the tube.

Abstract: A respiratory tract differential-pressure flow sensor, including a tube having a distal end that is insertable into a respiratory tract, an interfering body disposed within the tube proximal to the distal end and having a first edge facing one end of the tube and a second edge facing away from the end, the interfering body extending across the diameter of the tube, a first pressure sensing port operative to sense an air pressure, the first port being disposed in the first edge not abutting the wall of the tube, and a second pressure sensing port operative to sense an air pressure, the second port being disposed in the second edge not abutting the wall of the tube, where either of the edges is inclined inwardly towards the axis of the interfering body extending across the diameter of the tube.

Abstract: A differential-pressure flow sensor for airflow measurement in the presence of water condensation, for use with mechanical ventilators. The pressure-sensing ports at either end of the interfering body are displaced from the inner surface of the surrounding tubing, so as to prevent obstruction of the pressure-sensing ports by free flowing condensed water. The leading edge of the interfering body is angulated so as to deflect airflow towards the pressure-sensing port on the trailing edge of the interfering body, thereby flushing water droplets away from the port. The sides of the interfering body are sloped so as to generate turbulent boundary layer airflow at areas distant from the pressure-sensing ports, thereby encouraging water condensation away from the ports.

Abstract: A differential-pressure flow sensor for airflow measurement in the presence of water condensation, for use with mechanical ventilators. The pressure-sensing ports at either end of the interfering body are displaced from the inner surface of the surrounding tubing, so as to prevent obstruction of the pressure-sensing ports by free flowing condensed water. The leading edge of the interfering body is angulated so as to deflect airflow towards the pressure-sensing port on the trailing edge of the interfering body, thereby flushing water droplets away from the port. The sides of the interfering body are sloped so as to generate turbulent boundary layer airflow at areas distant from the pressure-sensing ports, thereby encouraging water condensation away from the ports.

Abstract: A message management system comprising apparatus for producing a multi-media message, including a visually sensible portion and an aurally sensible portion, control apparatus for transmitting the multi-media message to a selected subscriber and apparatus for providing notification to the selected subscriber of the arrival of a multi-media message.

Abstract: A message management system comprising apparatus for producing a multi-media message, including a visually sensible portion and an aurally sensible portion, control apparatus for transmitting the multi-media message to a selected subscriber and apparatus for providing notification to the selected subscriber of the arrival of a multi-media message.

Abstract: A message management system comprising apparatus for producing a multi-media message, including a visually sensible portion and a aurally sensible portion, control apparatus for transmitting the multi-media message to a selected subscriber and apparatus for providing notification to the selected subscriber of the arrival of a multi-media message.

Abstract: A message management system comprising apparatus for producing a multi-media message, including a visually sensible portion and an aurally sensible portion, control apparatus for transmitting the multi-media message to a selected subscriber and apparatus for providing notification to the selected subscriber of the arrival of a multi-media message.