MORE DATa study

Information on the extent of tissue damage after trauma, surgery, disease or therapy is an important paramter in the clinical evaluation of patients and can prevent complications. Unfortunately currently no reliable minimal invasive methods exist to examine such tissue damage. New insights in the kinetics of blood leukocytes after surgical procedures have shown that monitoring of tissue damage can be performed via small amounts of peripheral blood – the monocyte subpopulations change remarkebly in the early phase after surgery. Patients after total hip replacement demonstrated a massive increase of classical monocytes after a notable decrease, 24 hours after surgery. A possible explanation for this phenomenon could be massive recruitment from the bone marrow after large numbers of blood monocytes have migrated into the tissue. This bone marrow recruitment would then resemble the granulocytic left-shift that can be found during or after acute infections. If this hypothesis is correct, a large proportion of the classical monocytes should have a more ‘immature’ phenotype.

This study will evaluate the monocyte phenotype at several time points after a total hip replacement surgery (severe tissue damage) and a knee arthroscopy (minimal tissue damage).

The existence of a “monocyte left-shift” after (severe) tissue damaga.

5mL of peripheral blood will be drawn preoperatively and postoperatively, with a small margin, at 2 hr, 6 hr, 24 hr, 36 hr, 48 hr and 1 week.

5mL of peripheral blood will be drawn preoperatively and postoperatively, with a small margin, at 2 hr, 6 hr, 24 hr, 36 hr, 48 hr and 1 week. After blood samples have been obtained from the patients, the material will be transported at 4⁰C to the LUMC laboratory site for analysis.