Has anyone out there experienced any diathermy interference on the Sp02 parameter of the Philips (Hewlett Packard) Merlin Patient Monitor.

Interference on the ECG is to be expected, though, this seems to be at an acceptable level.
Even the Arterial BP waveform and values are not affected.

However, the "pleth." waveform and the O2 saturation value disappear (flat trace and no reading). Since the waveform recovery period following the event is usually several seconds, the Sp02 information is practically non-existent during periods of frequent use of the surgical diathermy.

This problem is not restricted to one monitor. All monitors in all our theatres are affected.

It looks like, the interference is transmitted through the patient rather than it being airborne, since it is less prominent when applying the sensor to an operator,obviously ensuring the actual sp02 probe is physically located in the same area when applied to the patient.

Any comments and/or suggestions are gratefully received.

Jan,
Yes I have seen this.
What probes do you use? The latest Nellcor ones have better EMI screening but you will need a M1900B interface cable.
Robert

If you are using a satellite rack you might want to check the integrity of the screen on your interface cable.
They are easily damaged, we had a similar problem where the monitor would lose all traces for up to 10 seconds. I can provide more details if you want.