title: Sampling time after tourniquet removal affects erythrocyte deformability and aggregation measurements.
abstract: Venipuncture procedures are widely thought to influence biochemical, hematological or hemorheological measurements. In line with the preparation of the new Guidelines for the standardization of hemorheological measurement, we compared various blood rheological parameters (i.e., red blood cell deformability and aggregation indices) assessed in blood samples obtained after 5, 30, 60 and 90 s following the tourniquet removal and a blood sample obtained without applying a tourniquet (control sample). A slight but significant improvement in red blood cell (RBC) deformability after the removal of tourniquet compared to the control sample was observed. RBC deformability was maximal in the samples obtained 30 s after tourniquet removal and remained slightly higher than the control in the following samples (at 60 and 90 s after tourniquet removal). The aggregation index (AI) decreased with time after tourniquet removal reaching significantly lower values than the control at 90 s after tourniquet removal. This finding was supported by a greater half time for RBC aggregation in the samples obtained 60 and 90 s after tourniquet removal. In conclusion, this study revealed that RBC deformability and aggregation might be significantly altered in the samples obtained after the application and removal of a tourniquet, as a part of the blood sampling procedure. Recommendation "remove the tourniquet at least 5 s prior to the start of blood sampling" may need to be revised.
authors.affiliation: Laboratoire ACTES (EA 3596), Département de Physiologie, Université des Antilles et de la Guyane, Guadeloupe. pconnes@yahoo.fr
authors.forename: Philippe
authors.initials: P
authors.lastname: Connes
authors.forename: Mehmet
authors.initials: M
authors.lastname: Uyuklu
authors.forename: Julien
authors.initials: J
authors.lastname: Tripette
authors.forename: John H
authors.initials: JH
authors.lastname: Boucher
authors.forename: Eric
authors.initials: E
authors.lastname: Beltan
authors.forename: Tawfik
authors.initials: T
authors.lastname: Chalabi
authors.forename: Ozlem
authors.initials: O
authors.lastname: Yalcin
authors.forename: Roger
authors.initials: R
authors.lastname: Chout
authors.forename: Olivier
authors.initials: O
authors.lastname: Hue
authors.forename: Marie-Dominique
authors.initials: MD
authors.lastname: Hardy-Dessources
authors.forename: Oguz K
authors.initials: OK
authors.lastname: Baskurt
mesh_terms: D015331:Cohort Studies; D004903:Erythrocyte Aggregation; D004907:Erythrocyte Deformability; D006801:Humans; D008297:Male; D018962:Phlebotomy / Q000009:adverse effects* / Q000379:methods* / Q000592:standards; D017410:Practice Guidelines as Topic; D014111:Tourniquets / Q000009:adverse effects