17 Monitoring Intravascular Oxygen Saturation
probe/catheter with forceps or a hemostat. Damage to the fiber results in low intensity light and a
sudden decrease in intensity readings. Refer to the documentation provided with the fibre-optic
probe/catheter, paying special attention to any precautions, warnings or contraindications.
Secure the optical module directly attached or in close proximity to the patient, to avoid placing
excessive tension on the catheter, which would result in movement of the catheter tip from the optimal
position in the patient.
Position the optical module to avoid contact with liquids. Fluid entering the catheter-optical module
connection will impair measurement performance.
You must perform an in-vivo calibration once the probe/catheter is in place.
The probe/catheter should be replaced after it has been in place for 72 hours.
Do not apply excessive tension to any cable or part of the catheter.
Performing In-Vivo Calibration
Perform an in-vivo calibration:
when you place the catheter in a patient.
if the catheter was disconnected from the optical module.
when the catheter has been in the patient for 24 hours.
if any significant change in light intensity occurs that the monitor cannot correct automatically.
Setting Up the In-Vivo Calibration
proper positioning of the probe/catheter in the patient.
relatively stable oxygen saturation in patient.
that the light intensity indicator is indicating a stable medium to high level.
Depending on the probe/catheter in use you may need to enter a catheter correction factor. This can
be found printed on the connector of the probe/catheter. The correction factor must only be entered
if it is different from the one currently stored. To see the current correction factor:
If the correction factor displayed is different from the one on the connector, note the correction
factor from the probe/catheter for entry during calibration.
Making the In-Vivo Calibration
Be prepared to draw a blood sample from the patient.
To clear the distal lumen, draw off and discard at least 2 ml of blood before taking the sample.
probe/catheter is thin and flexible, treat it carefully. Avoid kinking, bending or grasping the
Setup <SO₂ Label>
Setup <SO₂ Label>