Extracorporeal circuit sterility after 168 hours

One of the most important tasks of the perfusionist is the proper assembly of the extracorporeal circuit (ECC) prior to the initiation of cardiopulmonary bypass (CPB). The ECC is usually assembled, primed and debubbled 30 minutes to one hour prior to the patient entering the operating room. But there are occasions when the ECC may have been set up and the previously scheduled procedure cancelled. Perfusionists in this situation have found themselves in a quandary; dispose of the ECC because of required nursing compliance and the sterility question, or keep it and use it later because of the economic impact on the "bottom line". Some hospitals may have satisfactorily answered the question of ECC sterility after 24 hours without observation, but the few reported papers regarding this issue, and our desire to save these circuits, inspired us to find out if they were in fact sterile after having been open for a long period of time. The purpose of this study was to evaluate ECC sterility using an open reservoir oxygenator, over a time period of seven days. After obtaining 792 bacterial cultures from three sites within the ECC, the study was terminated. There were no positive bacterial cultures during the study period. Assuming there is no deliberate contamination, pump circuits assembled in an unused operating room can be maintained sterile for a period of seven days.