System and method for detection of venous pulsation

1. A method for detecting venous pulsation, comprising:

receiving one or more signals from a sensor, the signals corresponding to absorption of light in a patient's tissue;

determining a characteristic of the sensor;

performing a venous pulsation detection algorithm on the one or more signals, wherein the venous pulsation detection algorithm is performed at a sensitivity level based on the characteristic of the sensor; and

determining whether venous pulsation is present based on the performance of the venous pulsation detection algorithm.

2. The method of claim 1 , wherein determining the characteristic comprises determining an intended location of the sensor from an encoder in the sensor.

3. The method of claim 1 , wherein determining the characteristic comprises determining a location of the sensor from a user input.

4. The method of claim 1 , wherein determining the characteristic comprises determining a likely location of the sensor from a sensor location detection algorithm.

5. The method of claim 1 , wherein determining the characteristic comprises determining whether the sensor is located or intended to be located on a digit or forehead.

6. The method of claim 1 , wherein the sensitivity level of the venous pulsation detection algorithm is greater when the sensor is located at a site where venous pulsation is likely to occur than when the sensor is located at a site where venous pulsation is not likely to occur.

7. The method of claim 6 , wherein the sensitivity level of the venous pulsation detection algorithm is greater when the sensor is located on a forehead of the patient.

8. The method of claim 1 , comprising calculating one or more physiological parameters based on the one or more signals corresponding to absorption of light in the patient's tissue.

9. The method of claim 8 , comprising ceasing a display of values of the one or more physiological parameters when a criterion relating to detected venous pulsation is met.

10. The method of claim 8 , wherein the one or more physiological parameters comprise blood oxygen saturation, pulse rate, or a combination thereof.

11. The method of claim 1 , comprising providing an auditory or visual alarm when venous pulsation is detected.

12. The method of claim 1 , wherein the sensitivity level of the venous pulsation detection algorithm is determined by selecting the venous pulsation detection algorithm from among a plurality of venous pulsation detection algorithms with different sensitivities.

13. A method for preventing display of inaccurate measurements in the presence of venous pulsation, comprising:

receiving one or more signals from a sensor, the one or more signals corresponding to absorption of light in a patient's tissue;

determining a characteristic of the sensor;

calculating one or more physiological parameters of the patient based on the one or more signals;

determining if venous pulsation is present based on the one or more signals, wherein determining if venous pulsation is present comprises performing a venous pulsation detection algorithm at a sensitivity level based on the characteristic of the sensor; and

suspending or terminating a display of the one or more of the patient's physiological parameters based on detection of venous pulsation.

14. The method of claim 13 , wherein suspending the display of the one or more of the patient's physiological parameters comprises ceasing the display until venous pulsation is undetected for a period of time.

15. The method of claim 13 , wherein terminating the display of the one or more of the patient's physiological parameters comprises ceasing the display until a reset is activated.

16. The method of claim 13 , comprising suspending or terminating the display of the one or more of the patient's physiological parameters when venous pulsation is detected for at least a time equal to a time threshold.

17. The method of claim 16 , wherein the time threshold is about 40 seconds.

18. The method of claim 13 , wherein the one or more physiological parameters comprise blood oxygen saturation, pulse rate, or a combination thereof.

19. The method of claim 13 , comprising providing a notification of the presence of venous pulsation.

20. The method of claim 19 , wherein the notification comprises an auditory or visual alarm.

21. A method, comprising:

receiving a signal from a sensor indicating sensor type;

enabling or disabling a function configured to detect venous pulsation based on the sensor type and determining whether the venous pulsation is present when the function is enabled; and

subsequent to enabling or disabling the function, calculating one or more physiological parameters based on one or more received signals corresponding to absorption of light in a patient's tissue.

22. The method of claim 21 , wherein the function configured to detect venous pulsation is enabled when the location of the sensor is at a site where venous pulsation is likely to occur and is disabled when the location of the sensor is at a site where venous pulsation is not likely to occur.

23. The method of claim 22 , wherein the site where venous pulsation is likely to occur is a forehead of the patient and the site where venous pulsation is not likely to occur is a digit of the patient.

24. The method of claim 21 , comprising ceasing a display of values of the one or more physiological parameters when a criterion relating to detected venous pulsation is met.

25. The method of claim 21 , providing an auditory or visual alarm when venous pulsation is detected.

26. A method for detecting venous pulsation, comprising:

receiving one or more signals from a sensor, the one or more signals corresponding to absorption of light in a patient's tissue;

calculating one or more physiological parameters of the patient based on the one or more signals;

displaying the patient's physiological parameters;

enabling a function configured to detect venous pulsation with variable sensitivity based on a location of the sensor and determining whether the venous pulsation is present when the function is enabled; and

suspending or terminating the display of the one or more of the patient's physiological parameters when venous pulsation is detected.

27. The method of claim 26 , wherein the one or more physiological parameters comprise blood oxygen saturation, pulse rate, or a combination thereof.

28. The method of claim 26 , comprising suspending or terminating the display of the one or more of the patient's physiological parameters when venous pulsation is detected for at least a time threshold.

29. The method of claim 28 , wherein the time threshold is about 40 seconds.

30. The method of claim 26 , comprising determining the location of the sensor from an encoder in the sensor, a user input, a sensor location detection algorithm, or a combination thereof.

31. The method of claim 26 , wherein the function configured to detect venous pulsation is more sensitive when the sensor is located at a site where venous pulsation is likely to occur than when the sensor is located at a site where venous pulsation is not likely to occur.

32. The method of claim 31 , wherein the site where venous pulsation is likely to occur is a forehead of the patient and the site where venous pulsation is not likely to occur is a digit of the patient.

33. The method of claim 26 , providing an auditory or visual alarm when venous pulsation is detected.

34. The method of claim 26 , wherein the variable sensitivity is greater when the sensor is located on a forehead than when the sensor is located on a digit.

35. A system for detecting venous pulsation, comprising:

means for receiving one or more signals from a sensor, the signals corresponding to absorption of light in a patient's tissue;

means for determining a characteristic of the sensor;

means for performing a venous pulsation detection algorithm on the one or more signals, wherein the venous pulsation detection algorithm is performed at a sensitivity level based on the characteristic of the sensor; and

means for determining whether venous pulsation is present based on the performance of the venous pulsation detection algorithm.

36. The system of claim 35 , comprising means for providing an auditory or visual alarm when venous pulsation is detected.

37. The system of claim 35 , wherein the sensitivity level of the venous pulsation detection algorithm is greater when the sensor is located on a forehead than when the sensor is located on a digit.

38. A system for preventing display of inaccurate measurements in the presence of venous pulsation, comprising:

means for receiving one or more signals from a sensor, the one or more signals corresponding to absorption of light in a patient's tissue;

means for determining a characteristic of the sensor;

means for calculating one or more physiological parameters of the patient based on the one or more signals;

means for performing a venous pulsation detection algorithm on the one or more signals, wherein the venous pulsation detection algorithm is configured to perform at a sensitivity level based on the characteristic of the sensor;

means for determining if venous pulsation is present based on the one or more signals; and

means for suspending or terminating a display of the one or more of the patient's physiological parameters based on detection of venous pulsation.

39. The system of claim 38 , comprising means for providing an auditory or visual alarm when venous pulsation is detected.

40. A system for detecting venous pulsation, comprising:

means for receiving one or more signals from a sensor, the one or more signals corresponding to absorption of light in a patient's tissue;

means for calculating one or more physiological parameters of the patient based on the one or more signals;

means for displaying the patient's physiological parameters;

means for enabling a function for detection of venous pulsation with variable sensitivity based on a location of the sensor and determining whether the venous pulsation is present when the function is enabled; and

means for suspending or terminating the display of the one or more of the patient's physiological parameters when venous pulsation is detected.

41. The system of claim 40 , comprising means for providing an auditory or visual alarm when venous pulsation is detected.

42. The system of claim 40 , wherein the variable sensitivity is greater when the sensor is located on a forehead than when the sensor is located on a digit.

43. A system, comprising:

means for receiving a signal from a sensor indicating sensor type;

means for enabling or disabling a function for detection of venous pulsation based on the sensor type and determining whether the venous pulsation is present when the function is enabled; and

means for calculating one or more physiological parameters, subsequent to enabling or disabling the function, based on one or more received signals corresponding to absorption of light in a patient's tissue.

44. The system of claim 43 , comprising means for providing an auditory or visual alarm when venous pulsation is detected.