Dataset Information

Endothelial progenitor cell mobilization by preoperative exercise: a bone marrow response associated with postoperative outcome.

ABSTRACT:

Background

Preoperative anaemia is associated with increased morbidity in patients undergoing major surgery. Whether erythrocytes are the only bone-marrow-derived cell lineage that associates with increased surgical complications is unknown. This prospective observational trial studied the mobilization of endothelial progenitor cells (EPCs) in response to exercise in association with postoperative complications.

Methods

After IRB approval, 60 subjects undergoing major thoracic surgery were exercised to exhaustion (peak V?(O?)). Peripheral blood collected before and after peak exercise was quantified for EPC lineages by fluorescence-activated cell sorter analysis. Complication analysis was based on the Clavien-Dindo classification.

Results

Exhaustive exercise increased EPC [CD45-133+34+ cells=150 (0.00-5230) to 220 (0.00-1270) cells ?l(-1); median change (range)=20 (-4,180-860) cells ?l(-1); P=0.03] but not mature endothelial cell (EC) subpopulations. Pre-exercise levels [odds ratio (OR)=0.86, 95% confidence interval (CI): 0.37-2.00, P=0.72), change after exercise as a continuous variable (OR=0.95, 95% CI: 0.41-2.22, P=0.91) and a positive response after exercise (change >0 cells ?l(-1); OR=0.41, 95% CI: 0.13-1.28, P=0.12) were not statistically significantly associated with the incidence of postoperative complications. Post-hoc receiver operating characteristic curve analyses revealed that subjects with a CD45-133+34+ increase ?60 cells ?l(-1) in response to exercise suffered fewer postoperative complications [86% sensitivity, 48% specificity and AUC=0.67 (95% CI: 0.52-0.81)].

Conclusions

Preoperative exercise induces EPC into the peripheral circulation. Subjects with a poor EPC response had a pre-existing propensity for postoperative complications. This warrants further research into the role of bone marrow function as a critical component to endothelial repair mechanisms.

Clinical trial registration

IRB 2003-0434 (University of Texas M.D. Anderson Cancer Center, Houston, TX, USA).

SUBMITTER: Schier R

PROVIDER: S-EPMC6223791 | biostudies-literature |

REPOSITORIES: biostudies-literature

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