Matthew J Lawrence1, Sendhil Kumar2, Karl Hawkins3, Stuart Boden4, Harvey Rutt4, Gavin Mills5, Ahmed Sabra1, Roger H K Morris6, Simon J Davidson7, Nafieseh Badiei8, Martin R Brown8, Phylip R Williams8, Phillip A Evans9. 1. NISCHR Haemostasis Biomedical Research Unit, Morriston Hospital, Abertawe Bro Morgannwg University Health Board, Swansea, UK; NISCHR Haemostasis Biomedical Research Unit, College of Medicine, Swansea University, Swansea, UK. 2. Emergency Department, Morriston Hospital, Abertawe Bro Morgannwg University Health Board, Swansea, UK. 3. NISCHR Haemostasis Biomedical Research Unit, College of Medicine, Swansea University, Swansea, UK. 4. ECS, Faculty of Physical and Applied Sciences, University of Southampton, Southampton, UK. 5. NISCHR Haemostasis Biomedical Research Unit, Morriston Hospital, Abertawe Bro Morgannwg University Health Board, Swansea, UK. 6. School of Applied Science, University of Wales Institute Cardiff, Cardiff, UK. 7. Department of Haematology, Royal Brompton Hospital, Royal Brompton and Harefield NHS Foundation Trust, London, UK. 8. College of Engineering, Swansea University, Swansea, UK. 9. NISCHR Haemostasis Biomedical Research Unit, Morriston Hospital, Abertawe Bro Morgannwg University Health Board, Swansea, UK; NISCHR Haemostasis Biomedical Research Unit, College of Medicine, Swansea University, Swansea, UK; Emergency Department, Morriston Hospital, Abertawe Bro Morgannwg University Health Board, Swansea, UK. Electronic address: phillip.evans2@wales.nhs.uk.
Abstract
INTRODUCTION: We investigated the effect of progressive haemodilution on the dynamics of fibrin clot formation and clot microstructure using a novel rheological method. The technique measures clotting time (TGP), clot strength (G`GP), and quantifies clot microstructure (df) at the incipient stages of fibrin formation. We use computational modelling to examine the relationship between structure and mass, as well as helium ion microscopy (HIM) to compare morphological changes in the fully formed clot to that of the incipient clot. METHODS: This is an in vitro study; 90 healthy volunteers were recruited with informed consent and a 20ml sample of whole blood obtained from each volunteer. Five clinically relevant dilutions were investigated using 0.9w.v isotonic saline (0, 10, 20, 40 and 60%, n=18 for each dilution). The rheological method of assessing structural clot changes was compared against conventional coagulation screen and fibrinogen estimation. RESULTS: Fractal dimension (df) and final clot microstructure both decreased with progressive dilution (significant at a dilution of 20%) with similar relationships observed for final clot characteristics in HIM images. Significant correlations were observed between df and G`GP (clot strength) (0.345, p=0.02), as well as clotting time (PT: -0.690, p>0.001; APTT: -0.672, p>0.001; TGP: -0.385, p=0.006). CONCLUSIONS: This study provides new insight into the effects of haemodilution by isotonic saline on clotting time (TGP), clot strength (G'GP) and clot microstructure (df). Previous studies have attempted to link clot microstructure to clot quality/strength, however this study provides a significant step in quantifying these relationships.
INTRODUCTION: We investigated the effect of progressive haemodilution on the dynamics of fibrin clot formation and clot microstructure using a novel rheological method. The technique measures clotting time (TGP), clot strength (G`GP), and quantifies clot microstructure (df) at the incipient stages of fibrin formation. We use computational modelling to examine the relationship between structure and mass, as well as helium ion microscopy (HIM) to compare morphological changes in the fully formed clot to that of the incipient clot. METHODS: This is an in vitro study; 90 healthy volunteers were recruited with informed consent and a 20ml sample of whole blood obtained from each volunteer. Five clinically relevant dilutions were investigated using 0.9w.v isotonic saline (0, 10, 20, 40 and 60%, n=18 for each dilution). The rheological method of assessing structural clot changes was compared against conventional coagulation screen and fibrinogen estimation. RESULTS: Fractal dimension (df) and final clot microstructure both decreased with progressive dilution (significant at a dilution of 20%) with similar relationships observed for final clot characteristics in HIM images. Significant correlations were observed between df and G`GP (clot strength) (0.345, p=0.02), as well as clotting time (PT: -0.690, p>0.001; APTT: -0.672, p>0.001; TGP: -0.385, p=0.006). CONCLUSIONS: This study provides new insight into the effects of haemodilution by isotonic saline on clotting time (TGP), clot strength (G'GP) and clot microstructure (df). Previous studies have attempted to link clot microstructure to clot quality/strength, however this study provides a significant step in quantifying these relationships.
Authors: Gareth R Davies; Suresh Pillai; Matthew Lawrence; Gavin M Mills; Robert Aubrey; Lindsay D'Silva; Ceri Battle; Rhodri Williams; Rowan Brown; Dafydd Thomas; Keith Morris; Phillip Adrian Evans Journal: Intensive Care Med Date: 2016-09-03 Impact factor: 17.440
Authors: Sophia N Stanford; Ahmed Sabra; Lindsay D'Silva; Matthew Lawrence; Roger H K Morris; Sharon Storton; Martyn Rowan Brown; Vanessa Evans; Karl Hawkins; Phylip Rhodri Williams; Simon J Davidson; Mushtaq Wani; John F Potter; Phillip A Evans Journal: BMC Neurol Date: 2015-03-15 Impact factor: 2.474
Authors: N Badiei; A M Sowedan; D J Curtis; M R Brown; M J Lawrence; A I Campbell; A Sabra; P A Evans; J W Weisel; I N Chernysh; C Nagaswami; P R Williams; K Hawkins Journal: Clin Hemorheol Microcirc Date: 2015 Impact factor: 2.375
Authors: Nicholas J Marsden; Martin Van; Samera Dean; Ernest A Azzopardi; Sarah Hemington-Gorse; Phillip A Evans; Iain S Whitaker Journal: Scars Burn Heal Date: 2017-09-05
Authors: Lindsay D'Silva; Maria Wilczynska; Keir Lewis; Matthew Lawrence; Karl Hawkins; Rhodri Williams; Sophia Stanford; Simon Davidson; Keith Morris; Adrian Evans Journal: Sleep Sci Date: 2016-02-23
Authors: Ahmed Sabra; Matthew James Lawrence; Robert Aubrey; Daniel Obaid; Alexander Chase; Dave Smith; Phillip Thomas; Sharon Storton; Gareth R Davies; Karl Hawkins; Phylip Rhodri Williams; Keith Morris; Phillip Adrian Evans Journal: Open Heart Date: 2017-06-23