title: The role of whole blood impedance aggregometry and its utilisation in the diagnosis and prognosis of patients with systemic inflammatory response syndrome and sepsis in acute critical illness.
abstract: OBJECTIVE
  To assess the prognostic and diagnostic value of whole blood impedance aggregometry in patients with sepsis and SIRS and to compare with whole blood parameters (platelet count, haemoglobin, haematocrit and white cell count).
  
  
  METHODS
  We performed an observational, prospective study in the acute setting. Platelet function was determined using whole blood impedance aggregometry (multiplate) on admission to the Emergency Department or Intensive Care Unit and at 6 and 24 hours post admission. Platelet count, haemoglobin, haematocrit and white cell count were also determined.
  
  
  RESULTS
  106 adult patients that met SIRS and sepsis criteria were included. Platelet aggregation was significantly reduced in patients with severe sepsis/septic shock when compared to SIRS/uncomplicated sepsis (ADP: 90.7±37.6 vs 61.4±40.6; p<0.001, Arachadonic Acid 99.9±48.3 vs 66.3±50.2; p = 0.001, Collagen 102.6±33.0 vs 79.1±38.8; p = 0.001; SD ± mean)). Furthermore platelet aggregation was significantly reduced in the 28 day mortality group when compared with the survival group (Arachadonic Acid 58.8±47.7 vs 91.1±50.9; p<0.05, Collagen 36.6±36.6 vs 98.0±35.1; p = 0.001; SD ± mean)). However haemoglobin, haematocrit and platelet count were more effective at distinguishing between subgroups and were equally effective indicators of prognosis. Significant positive correlations were observed between whole blood impedance aggregometry and platelet count (ADP 0.588 p<0.0001, Arachadonic Acid 0.611 p<0.0001, Collagen 0.599 p<0.0001 (Pearson correlation)).
  
  
  CONCLUSIONS
  Reduced platelet aggregometry responses were not only significantly associated with morbidity and mortality in sepsis and SIRS patients, but also correlated with the different pathological groups. Whole blood aggregometry significantly correlated with platelet count, however, when we adjust for the different groups we investigated, the effect of platelet count appears to be non-significant.
authors.affiliation: Institute of Life Science, College of Medicine, Swansea University, Singleton Park, Swansea, Wales, United Kingdom.
authors.forename: Gareth R
authors.initials: GR
authors.lastname: Davies
authors.affiliation: NISCHR Haemostasis Biomedical Research Unit (HBRU), Morriston Hospital, Swansea, Wales, United Kingdom.
authors.forename: Gavin M
authors.initials: GM
authors.lastname: Mills
authors.affiliation: NISCHR Haemostasis Biomedical Research Unit (HBRU), Morriston Hospital, Swansea, Wales, United Kingdom; Institute of Life Science, College of Medicine, Swansea University, Singleton Park, Swansea, Wales, United Kingdom.
authors.forename: Matthew
authors.initials: M
authors.lastname: Lawrence
authors.affiliation: NISCHR Haemostasis Biomedical Research Unit (HBRU), Morriston Hospital, Swansea, Wales, United Kingdom; Intensive Therapy Unit, Abertawe Bro Morgannwg University Health Board, Swansea, Wales, United Kingdom.
authors.forename: Ceri
authors.initials: C
authors.lastname: Battle
authors.affiliation: NISCHR Haemostasis Biomedical Research Unit (HBRU), Morriston Hospital, Swansea, Wales, United Kingdom; School of Applied Science, University of Wales Institute Cardiff, Cardiff, Wales, United Kingdom.
authors.forename: Keith
authors.initials: K
authors.lastname: Morris
authors.affiliation: NISCHR Haemostasis Biomedical Research Unit (HBRU), Morriston Hospital, Swansea, Wales, United Kingdom; Institute of Life Science, College of Medicine, Swansea University, Singleton Park, Swansea, Wales, United Kingdom.
authors.forename: Karl
authors.initials: K
authors.lastname: Hawkins
authors.affiliation: College of Engineering, Swansea University, Singleton Park, Swansea, Wales, United Kingdom.
authors.forename: Phylip Rhodri
authors.initials: PR
authors.lastname: Williams
authors.affiliation: Department of Haematology, Royal Brompton and Harefield NHS Foundation Trust, London, United Kingdom.
authors.forename: Simon
authors.initials: S
authors.lastname: Davidson
authors.affiliation: NISCHR Haemostasis Biomedical Research Unit (HBRU), Morriston Hospital, Swansea, Wales, United Kingdom; Cardiac Intensive Care Unit, Abertawe Bro Morgannwg University Health Board, Swansea, Wales, United Kingdom.
authors.forename: Dafydd
authors.initials: D
authors.lastname: Thomas
authors.affiliation: NISCHR Haemostasis Biomedical Research Unit (HBRU), Morriston Hospital, Swansea, Wales, United Kingdom; Institute of Life Science, College of Medicine, Swansea University, Singleton Park, Swansea, Wales, United Kingdom.
authors.forename: Phillip Adrian
authors.initials: PA
authors.lastname: Evans
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016718:Arachidonic Acid / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001792:Blood Platelets / Q000378:metabolism / Q000473:pathology*; D003094:Collagen / Q000097:blood; D016638:Critical Illness; D017097:Electric Impedance; D005260:Female; D006400:Hematocrit; D006801:Humans; D007362:Intensive Care Units; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation; D010976:Platelet Count; D011379:Prognosis; D011446:Prospective Studies; D018805:Sepsis / Q000097:blood / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D016019:Survival Analysis; D018746:Systemic Inflammatory Response Syndrome / Q000097:blood / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D014914:Whole Blood Coagulation Time
chemical_list: D015415:Biomarkers; D016718:Arachidonic Acid; D003094:Collagen