Perfusion Policies 101: Oxygenator Changeout


FA 2016

Editor’s Note:


Welcome to PERFUSION POLICIES 101.  This will be a continuing series provided to assist your programs with that one puzzle piece we all run into now and then- that one time that an unexpected patient condition may give you pause…

The intention here is to disseminate some basic recipes that have probably been implemented at countless institutions, for God knows how long.  The usual disclaimers obviously apply:

Due Diligence is the Responsibility of the Reader!

Use the information as you feel fit, recognizing that this is information gleaned from multiple sources, it is recruited from the public domain of the internet, with no implied assurance of accuracy- but is cogent, and based on logical and reasonable clinical rationale.




From FB- a very cogent observation and clinical tip 🙂

Shawn Comrie Thanks for this and your other most practical articles. Regarding change out, I just want to point out that another thing to check is Flowmeter Air Pressure on the wall. I was involved in a case, where the blood went black. We were just about to change Oxy when I checked the wall gauge to find Air Pressure well exceeding specs, (For Sechrist Blender 210-490KPa), which meant it was overriding the Oxygen flow. We connected an O2 cylinder and once workshops had reduce the pressure to normal, we (all!) recovered! We could well have gone through the hazard of Oxy change out, only to have the same problem! (Would have been an absolute nightmare!) It was a strange hospital, strange pump, and the air pressure had been turned up the day before for an eye op. The blender should have alarmed but did not. (And we should have checked the wall air. Not something we routinely do but in this strange hospital?)

Frank Aprile thanks for the positive feedback and sharing the information- that was a very cogent observation on your part- I’ll keep that air pressure nugget in the back of my head I updated the article to include your observation 

Oxygenator Changeout


Is your oxygenator failing?  Mechanical considerations need to be evaluated before oxygenator changeout.


  1. Is oxygen being delivered to the oxygenator?
  2. Is the gas path obstructed?
  3. Is the gas connected to the correct ort?
  4. Are FiO2 and gas flow appropriate?

Patient considerations need to be evaluated

  1. Is the hematocrit adequate?
  2. What is the temperature?
  3. Is blood flow adequate?
  4. Are anesthesia and relaxant levels adequate?


Calculate O2 transfer of your oxygenator.

(arterial O2 content – venous O2 content) x (10) x (flow in LPM)

Art. Content= [9ven. Sat.%) x (1.34ml O2)x(Hgb gm %)]+[(PaO2)(.003)]

Ven. Content=[(ven.sat.%)(1.34ml O2)(Hgb gm %)]+[(PvO2)(.003)]

Maximum Value = 360ml/min @ blood flow 6L/min

Gas flow 15L/min

Blood temp 37*C

Hemoglobin 12g/dl


  1. oxygenator
  2. tubing clamps – 4
  3. 400 ml of prime solution
  4. sterile scissors


Prepare to change out the oxygenator by getting any necessary extras into the room, including additional perfusionists, oxygenators, clamps, sterile scissors, etc.  Notify the surgical team of your intentions and discuss your plans.  If possible, terminate cardiopulmonary bypass (CPB) and remind anesthesia to ventilate.  If changeout during bypass is unavoidable, then the following protocol should be observed.  Turn off water lines and disconnect from oxygenator.  Prep lines for sterile severance (alcohol).  Remove new oxygenator from package.  Come off bypass and clamp the arterial and venous lines to the patient and open the AV bridge.  Clamp out the arterial filter and/or open the filter bypass.  Double clamp all inlets and outlets of the oxygenator where you have previously prepped.  Using sterile scissors, cut inlet and outlet tubings and remove the failed oxygenator.  Insert new oxygenator into circuit and deair through the bridge.  Replace oxygen delivery line to air/O2 inlet on new oxygenator.  Open the arterial filter and clamp/close the arterial filter bypass while recirculating.  Deair filter.  Come off recirculation and clamp the AV bridge.  Reinitiate CPB as soon as possible.  Reconnect water lines and open valves.  Reuse checklist to confirm adequate reinitiation of CPB.