title: Microarterial anastomoses: A parameterised computational study examining the effect of suture position on intravascular blood flow.
abstract: This study investigates the extent to which individual aspects of suture placement influence local haemodynamics within microarterial anastomoses. An attempt to physically quantify flow characteristics of blood past microvascular sutures is made using computational fluid dynamics (CFD) software. Particular focus has been placed on increased shear strain rate (SSR), a known precipitant of intravascular platelet activation and thrombosis. Measurements were taken from micrographs of sutured anastomoses in chicken femoral vessels, with each assessed for bite width, suture angle and suture spacing. Computational geometries were then created to represent the anastomosis. Each suture characteristic was parameterised to allow independent or simultaneous adjustment. Flow rates were obtained from anonymised Doppler ultrasound scans of analogous vessels during preoperative assessment for autologous breast reconstruction. Vessel simulations were performed in 2.5mm ducts with blood as the working fluid. Vessel walls were non-compliant and a continuous Newtonian flow was applied, in accordance with current literature. Suture bite angle and spacing had significant effects on local haemodynamics, causing notably higher local SSRs, when simulated at extremes of surgical practice. A combined simulation, encompassing subtle changes of each suture parameter simultaneously i.e. representing optimum technique, created a more favourable SSR profile. As such, haemodynamic changes associated with optimum suture placement are unlikely to influence thrombus formation significantly. These findings support adherence to the basic principles of good microsurgical practice.
authors.affiliation: Department of Plastic & Reconstructive Surgery, University Hospital of South Manchester, Southmoor Road, Wythenshawe, Manchester M23 9LT, UK; School of Postgraduate Medicine and Dentistry, University of Central Lancashire, Fylde Road, Preston, Lancashire PR1 2HE, UK; School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Fylde Road, Preston, Lancashire PR1 2HE, UK. Electronic address: richwain@doctors.org.uk.
authors.forename: R A J
authors.initials: RA
authors.lastname: Wain
authors.affiliation: School of Postgraduate Medicine and Dentistry, University of Central Lancashire, Fylde Road, Preston, Lancashire PR1 2HE, UK; School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Fylde Road, Preston, Lancashire PR1 2HE, UK.
authors.forename: D
authors.initials: D
authors.lastname: Hammond
authors.affiliation: School of Postgraduate Medicine and Dentistry, University of Central Lancashire, Fylde Road, Preston, Lancashire PR1 2HE, UK; School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Fylde Road, Preston, Lancashire PR1 2HE, UK.
authors.forename: M
authors.initials: M
authors.lastname: McPhillips
authors.affiliation: School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Fylde Road, Preston, Lancashire PR1 2HE, UK.
authors.forename: J P M
authors.initials: JP
authors.lastname: Whitty
authors.affiliation: School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Fylde Road, Preston, Lancashire PR1 2HE, UK.
authors.forename: W
authors.initials: W
authors.lastname: Ahmed
mesh_terms: D000714:Anastomosis, Surgical; D000818:Animals; D002645:Chickens; D003198:Computer Simulation; D005260:Female; D005263:Femoral Artery / Q000000981:diagnostic imaging / Q000502:physiology / Q000601:surgery*; D006439:Hemodynamics; D006801:Humans; D016462:Mammaplasty / Q000295:instrumentation*; D008866:Microsurgery / Q000295:instrumentation*; D055806:Microvessels / Q000000981:diagnostic imaging / Q000502:physiology / Q000601:surgery*; D008955:Models, Cardiovascular; D012039:Regional Blood Flow; D013536:Suture Techniques / Q000295:instrumentation*; D013537:Sutures; D018608:Ultrasonography, Doppler
keywords: Anastomosis; Blood flow; Computational fluid dynamics (CFD); Computational modelling; Microarterial; Microvascular; Parameterised; Suture