Contamination of salvaged maternal blood by amniotic fluid and fetal red cells during elective Caesarean section

Cell salvage in obstetrics is still a controversial subject and has yet to be fully embraced. The aim of this exploratory study was to measure amniotic fluid (AF), heparin, and fetal red cell contamination of washed filtered salvaged maternal blood and to investigate differences based on the number of suction devices used.

Patients undergoing elective Caesarean section were assigned alternately to one of two groups. In Group 1, all blood and AF was collected with one suction. In Group 2, AF was aspirated to waste with a second separate suction device before collection of any blood.

In both groups, alpha-fetoprotein (AFP), squames cells, and heparin were significantly reduced (P<0.001) by the washing and filtering process. Mean AFP levels post-filtration were 2.58 IU ml(-1) in Group 1 and 3.53 IU ml(-1) in Group 2. Squames cells were completely removed in all but two cases. Fetal red blood cells were still present in the final product, range 0.13-4.35%. In Group 1, haemoglobin and haematocrit were higher than in Group 2, with lower white blood cell, AFP, and fetal red cell counts.

This study adds to the growing body of evidence that there is little or no possibility for AF contamination to enter the re-infusion system when used in conjunction with a leucodepletion filter.