Nellcor Puritan Bennett Incorporated

Nellcor Incorporated

Other

Robert S Potratz

David B Swedlow

Michael W Nootbaar

A lightweight inflation device for outputting a low-pressure airflow to inflate an air bladder includes a body defining an airflow chamber and a plurality of air manipulation elements disposed within the airflow chamber. At least one of the air manipulation elements is a rotor including a plurality of blades, and the inflation device includes a driving mechanism operable to rotate the blades about an axis. The inflation device further includes a nozzle operably coupled with the body and defining an air outlet to connect with a valve on the air bladder. The nozzle is shiftable into an operating position in which the air outlet extends beyond an outlet-side axial margin of the body. The nozzle is also shiftable into a storage position in which the air outlet is disposed within the airflow chamber of the body. A method of inflating an air bladder with a portable axial compressor assembly is also disclosed.

Lightweight inflation device

A preferred oximeter detects the transillumination by red and infrared light of a portion of an in vivo subject and produces analog signals representative thereof on two channels. Sigma-delta modulators sample the analog signals on each channel. A digital filter processor digitally filters the sample signals from both modulators to produce respective digital signals with multi-bit resolution.

Pulse oximeter with sigma-delta converter

A lamp drive circuit periodically energizes a lamp above its rated voltage and current for rapid illumination of the lamp. In the preferred embodiment, the lamp is connected in a voltage divider and the circuit monitors the voltage drop across the lamp. The voltage drop is indicative of the lamp resistance and thereby the temperature. When the voltage drop reaches a predetermined limit corresponding to the temperature rating of the lamp, it is de-energized and allowed to cool during the remainder of the cycle thereby enabling a high modulation frequency.

Lamp modulation circuit having a feedback for measuring lamp temperature

A compact pulse oximetry system and method which separates the combined signal into its respective AC and DC components. By separating the signal into AC and DC components, a smaller order bit A/D converter may be used while still maintaining signal accuracy. Instead of using the combined signal to calculate the oxygen saturation content, the system microprocessor computes the Ratio of Ratios using the derivative of the separated AC component of the diffused signal to calculate the oxygen saturation of the measured fluid. To calculate the Ratio of Ratios, a ratio of the derivative value of the separated AC component is used. Instead of taking a single sample between the peak and valley of the signal, the oximeter system samples each value. To decrease the effect of system noise, a linear regression is performed over each sample.

Condensed oximeter system and method with noise reduction software

A pulse oximeter which modifies the alarm condition when motion is detected. Basically, if the lack of a pulse is determined to be as a result of motion artifact, the generation of an alarm is postponed. In addition, the display indicates that motion is present and that the last reading is questionable due to the presence of motion. The invention also determines if motion artifact is present from the pulse oximeter detector signal itself. The ratio of the positive and negative peaks of the derivative of the pulse signal are compared to a motion/blood pulse threshold.

Oximeter with motion detection for alarm modification

A compact pulse oximetry system which separates the combined signal into its respective AC and DC components. By separating the signal into AC and DC components, a smaller order bit A/D converter may be used while still maintaining signal accuracy. Instead of using the combined signal to calculate the oxygen saturation content, the system microprocessor computes the Ratio of Ratios using the derivative of the separated AC component of the diffused signal to calculate the oxygen saturation of the measured fluid. To calculate the Ratio of Ratios, a ratio of the derivative value of the separated AC component is used. Instead of taking a single sample between the peak and valley of the signal, the oximeter system samples each value. To decrease the effect of system noise, a linear regression is performed over each sample.

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Lenexa, KS, United States of America

Robert S Potratz