Is use of a Continuous Autotransfusion System beneficial in emergency abdominal aortic aneursym (AAA) surgery?

Allogeneic blood products have become a limited and expensive resource. The Continuous Autotransfusion System (CATS) has been promoted as a method for reducing the need for allogeneic blood transfusion. This study was undertaken to ascertain whether the use of CATS in emergency open AAA surgery has any benefits.

This is a retrospective study of all patients undergoing emergency open AAA surgery in our center during a 5-year period (between July 2004 and July 2009). Patients were identified from a prospectively maintained vascular database, and data were obtained from patient records.

CATS was used in 69 emergency open AAA repairs. The median total blood loss was 3,500 mL (range: 751-13,796 mL) but the median volume of packed red blood cells produced by CATS was only 493 mL (~ 2 U). An average of 7 U (range: 0-19 U) of bank blood was still used despite the availability of CATS. The mean hemoglobin 24 hours postoperatively was 10.3 g/dL (6.4-14.1) with a hematocrit of 0.30.

The use of CATS in emergency AAA surgery does not seem to reduce the use of allogeneic blood transfusion. This may be because of over transfusion, as reflected by relatively high postoperative hemoglobin levels.