Fig. 2.

Survival curves in Staphylococcus aureus-challenged [Reprinted from Cortés-Puch et al. (54)] dogs comparing unwashed and washed blood. Kaplan–Meier plots throughout the 96-h study comparing the four types of transfused blood. The different types of blood are represented by different line patterns as follows: dashed black line (42-day-old unwashed blood), solid black line (42-day-old washed blood), solid grey line (7-day-old washed blood) and dashed grey line (7-day-old unwashed blood). There is a qualitative interaction between washing and the age of stored blood (P = 0·03). Reprinted from Cortés-Puch et al. [54]. *Qualitative interaction: there was a significantly different and opposite effect of washing on survival times depending on the age of blood, i.e., washing improves survival rates of 42-day-old and worsens survival rates of 7-day-old stored blood.