Studies of Bacterial Transfusion Reactions From Refrigerated Blood: The Properties of Cold-Growing Bacteria 1

Red Cell Banking and the Production of a Factor VIII Concentrate

“…Further, from a number of studies [6,23,10,30,4] of the properties of typical cold-growing organisms it can be concluded (a) that the minimum lethal con centration is of the order of 10s to 1010 organisms per ml, and (b) that the time re quired for this concentration to be reached in blood containing an inoculum of say 5 organisms per ml is 12 to 14 days (at +4° to A 6°C). It appears likely that provided the cell concentrate is adequately refrigerated, and the initial inoculum is small, the main risk from bacterial contamination develops only after 10 to 12 days of storage.…”

Bacterial Contamination of Preserved Blood

“…The problem of contamination of stored blood assumes different dimensions in different countries and comparisons are not only in vidious but are rendered difficult by the divergence of methods and conditions met with; for instance, some workers [1] have assessed the incidence of infection in a bottle of stored blood in the United States at l%-3%, while others [2] suggest a figure of 2.2% and further investigators in this field [3] failed to find any organisms in 200 bottles of outdated bank blood.…”

“…The addition of antibiotics to the blood [2], though at first sight an attractive proposition, has on closer examination disadvantages which outweigh any increase in security thus obtained, in that (a) hypersensitive recipients would be adversely affected, (b) it is not certain that all strains of cold-growing organisms are sensitive to any one drug, and (c) the antibiotic could not be autoclaved and as it might itself be contaminated a distinct risk would be attached to adding it to the bottle.…”

Effect of Temperature on Survival of Bacteria in Blood for Transfusion

“…The highest count in four experiments with rubber wads was 276 colonies and the highest from single fingerprints of six people was 97 colonies. Contamination from the air is considered by some to be a serious menace even when blood is collected by a closed method (Braude et al, 1952), but the risk is probably overestimated. The highest bacterial counts in air are found in wards during bed-making, where there may be 2,000 bacteria-carrying particles per cubic foot (70,600 per cubic metre) of air.…”

“…It has been suggested that the addition of small doses of tetracycline to blood would prevent growth and do no harm to the recipient (Braude et al, 1955). We are not in favour of this, because it is doubtful if all strains cof cold-growers are sensitive to any one drug; moreover, antibiotics are not stable, and would therefore have to be added to the bottle after autoclaving, and they are themselves sometimes contaminated.…”