The Mechanics of the Circulation

551 Pages·2012·28.88 MB·English

by  C. G. Caro, T. J. Pedley, R. C. Schroter, W. A. Seed, K. H. Parker

THE MECHANICS OF THE CIRCULATION
second edition
Continuing demand for this book confirms that it remains relevant over 30 years
afteritsfirstpublication.Thefundamentalexplanationsarelargelyunchanged,but
intheintroductiontothissecondeditiontheauthorsareonhandtoguidethereader
throughmajoradvancesofthelastthreedecades.
With an emphasis on physical explanation rather than equations, Part I clearly
presentsthebackgroundmechanics.Thesecondpartappliesmechanicalreasoning
to the component parts of the circulation: blood, the heart, the systemic arteries,
microcirculation,veinsandthepulmonarycirculation.Eachsectiondemonstrates
howanunderstandingofbasicmechanicsenhancesourunderstandingofthefunc-
tionofthecirculationasawhole.
This classic book is of value to students, researchers and practitioners in bio-
engineering, physiology and human and veterinary medicine, particularly those
working in the cardiovascular field, and to engineers and physical scientists with
multidisciplinaryinterests.
‘...essential reading for anyone who is interested in the mechanics of the circu-
lation. The normally incomprehensible mechanical laws are explained so clearly
thateventhenon-mathematicallymindedwillhavenodifficulty,whichmakesme
verysorrythatitwasnotavailablewhenIwasgrapplingwiththeseproblems.’
DAVIDMENDEL,JournaloftheRoyalSocietyofMedicine
‘Like a good sculpture which leaves no chisel marks on the marble, there are no
marks of individual specialization in this book. All is well integrated toward the
physiology of circulation ...After reading the book, one would wonder how can
circulationphysiologybeunderstoodwithoutsuchastudyofmechanics.Itcannot!
Irecommendthisbooktoallphysiologyteachersandstudents.’
Y.C.FUNG,JournalofBiomechanicalEngineering
‘Here is a book on the mechanics of the circulation that is equally accessible to
thosetrainedinthelifesciencesandinthemechanicalsciences.’
SIRJAMESLIGHTHILL,JournalofFluidMechanics

THE MECHANICS OF
THE CIRCULATION
second edition
C.G. CARO
ImperialCollege
T.J. PEDLEY
UniversityofCambridge
R.C. SCHROTER
ImperialCollege
W.A. SEED
ImperialCollege
WiththeAssistanceof
K.H. PARKER
ImperialCollege
cambridge university press
Cambridge,NewYork,Melbourne,Madrid,CapeTown,
Singapore,Sa˜oPaulo,Delhi,Tokyo,MexicoCity
CambridgeUniversityPress
TheEdinburghBuilding,CambridgeCB28RU,UK
PublishedintheUnitedStatesofAmericabyCambridgeUniversityPress,NewYork
www.cambridge.org
Informationonthistitle:www.cambridge.org/9780521151771
(cid:1)C CambridgeUniversityPress2012
Thispublicationisincopyright.Subjecttostatutoryexception
andtotheprovisionsofrelevantcollectivelicensingagreements,
noreproductionofanypartmaytakeplacewithoutthewritten
permissionofCambridgeUniversityPress.
Firstpublished2012
PrintedintheUnitedKingdomattheUniversityPress,Cambridge
AcataloguerecordforthispublicationisavailablefromtheBritishLibrary
LibraryofCongressCataloguinginPublicationdata
Themechanicsofthecirculation/C.G.Caro...[etal.].–2nded.
p. cm.
Includesbibliographicalreferencesandindex.
ISBN978-0-521-15177-1(pbk.)
1.Hemodynamics. 2.Blood–Circulation. I.Caro,ColinG.(ColinGerald) II.Title.
QP105.M4 2011
612.1(cid:2)1–dc23 2011027494
ISBN978-0-521-15177-1Paperback
CambridgeUniversityPresshasnoresponsibilityforthepersistenceor
accuracyofURLsforexternalorthird-partyinternetwebsitesreferredto
inthispublication,anddoesnotguaranteethatanycontentonsuch
websitesis,orwillremain,accurateorappropriate.
Contents
Foreword pagexiii
PrefacetotheFirstEdition xvii
Acknowledgements xx
IntroductiontotheSecondEdition xxi
PartI Backgroundmechanics 1
1 Particlesandcontinuousmaterials 3
2 Particlemechanics 7
Position 7
Velocity 8
Acceleration 12
Newton’slawsofmotion: massandforce 14
Momentum 20
Workandenergy 20
3 Units 24
Thedifferencebetweenunitsanddimensions 24
Mass,length,andtimeasfundamentalunits 25
Theinconvenienceofforceasafundamentalunit 26
Energyandheat 27
Theconceptofsubstance 27
Dimensionalhomogeneityandconsistencyofunits 27
Theuseofvolumeandflowrateinphysiology 27
Syste`meInternational(SI) 28
4 Basicideasinfluidmechanics 31
Stress 31
Hydrostaticpressure 33
Stressinamovingfluid: viscosity 35
Theequationofmotionofafluid 38
v
vi Contents
Convectiveandlocalacceleration 40
Conservationofmass 41
Bernoulli’stheorem 42
5 Flowinpipesandaroundobjects 45
Poiseuilleflowinatube 45
Flowintheentranceregion 50
Theideaoftheboundarylayer 52
Reynoldsnumber 55
Turbulenceinpipeflow 56
Unsteadyflowinaverylongpipe 58
Effectsofconstrictionsonpipeflowcharacteristics 61
Flowincurvedpipes 66
Flowpastbodies 69
6 Dimensionalanalysis 80
Similarityandtheideaofscalemodels 81
Someexamplesofscalinginbiologicalsystems 81
Amethodofobtaininghomogeneousrelationshipsbetweenvariables 82
7 Solidmechanicsandthepropertiesofbloodvesselwalls 86
Definitionsofelasticproperties 86
Thepropertiesofbloodvesselwalls 91
Staticsofanelastictube 100
8 Oscillationsandwaves 105
Simpleharmonicmotion 105
Simplewaves 112
Damping 116
Wavereflectionsandresonance 120
Linearity 123
Fourieranalysis 126
9 Anintroductiontomasstransfer 128
Diffusion 129
Thecolloidalstate 133
Masstransfercoefficients 133
Diffusionthroughporesandmembranes 135
Restricteddiffusion 136
Activetransport 137
Permeability 138
Filtrationthroughmembranes 138
Osmosis 139
Asimplemasstransfermodel 141
Contents vii
Theinteractionofbulkflowanddiffusion 142
TheSchmidtnumber 145
PartII Mechanicsofthecirculation 147
10 Blood 149
Viscosityoffluidsandsuspensions 149
Sphericalparticles 151
Asymmetricparticles 154
Viscosityofplasma 155
Osmoticpressureofplasma 156
Thesuspendedelements 157
Thebloodcells 157
Redcells 158
Whitecells 165
Platelets 165
Bloodcoagulation 167
Thrombosis 168
Mechanicalpropertiesofwholeblood 169
Sedimentationofredcells 170
Principlesofmeasurementofbloodviscosity 171
Viscouspropertiesofblood 174
11 Theheart 178
Anatomyoftheheart 179
Thecardiaccycle 183
Electricalevents 183
Mechanicalevents 184
Propertiesofcardiacmuscle 186
Structure 186
Staticmechanicalpropertiesofcardiacmuscle 189
Dynamicmechanicalpropertiesofcardiacmuscle 191
Summary 201
Mechanicalbehaviouroftheintactheart 202
Leftventricularshapeandwallstresses 204
Rightventricularshape 209
Themechanicsoftheentireventricle 210
Summary 224
Fluidmechanicalaspectsofcardiacfunction 225
Rightheart 225
Leftheart 227
Soundsandmurmursintheheart 234
viii Contents
Sounds 234
Murmurs 236
Furtherreading 237
12 Thesystemicarteries 238
Anatomyandstructure 239
Theanatomyoflargebloodvessels 239
Branchingratiosandangles 241
Thestructureofthearterialwall 244
Arterialwallthickness 250
Changesinthearterialwallwithage 251
Bloodpressureandflowinsystemicarteries 255
Transmuralpressures 256
Unsteadypressureinlargearteries 259
Flow 262
Terminology 265
Fourieranalysis 266
Wavepropagationinarteries 269
TheWindkesselmodel 270
Thepropagationofthepressurewave 271
Determinationofthewavespeed 272
Comparisonoftheorywithexperiment 275
Furtherlimitationsofthesimpleelasticmodel 277
Reflectionandtransmissionofthewaveatjunctions 278
Reflectionatasinglejunction 278
Thematchingofimpedances 281
Positiveandnegativereflection 283
Physiologicalevidenceofwavereflections 285
Multiplereflections 288
Interpretationofobservedpressurewaveformsinlargearteries 291
Theeffectoftaper 294
Theinfluenceofnonlinearities 297
Viscouseffects 299
Effectofbloodviscosityonflow-ratewaveform 299
Effectofviscosityonwavepropagation 301
Effectofwallvisco-elasticity 304
Othertypesofwave 304
Flowpatternsinarteries 306
Velocityprofilesinlargearteries 306
Physicalmechanismsunderlyingthevelocityprofiles 313
Stabilityandturbulence 321
Contents ix
Mixingandmasstransportinarteries 328
Mixingintheheartandlargebloodvessels 328
Masstransportacrossarterywalls 333
Appendix: Impedance 338
Furtherreading 341
13 Thesystemicmicrocirculation 343
Theorganizationofamicrovascularbed 344
Thearteriolarsystem 344
Thecapillarysystem 346
Thevenularsystem 349
Thelymphaticsystem 350
Thestructureofthevesselsofthemicrocirculation 350
Thearterioles 351
Thecapillaries 353
Thevenules 358
Thelymphatics 360
Thejunctionsbetweenvascularendothelialcells 360
Thepinocyticvesicles 363
Theinterstitialspace 363
Staticmechanicalpropertiesofthemicrocirculatoryvessels 363
Elasticpropertiesofthearterioles 364
Mechanicalpropertiesofthecapillaries 366
Elasticpropertiesofthevenules 368
Pressureinthemicrocirculation 368
Thedistributionofpressure 368
Thepropagationofcardiacpressureoscillations 375
Pressureintheinterstitialspace 376
Flowinmodelsandinthelargevesselsofthemicrocirculation 378
Themotionofsingleparticlesatverylowflowrates 378
Themotionofsingleparticlesathighflowrates 381
ThemotionofsingleredbloodcellsinPoiseuilleflow 381
Theflowofconcentratedsuspensionsofparticlesandredcells 384
Theviscosityofwholeblood 386
Radialdispersionofredcells 387
Thecell-freelayer 387
Velocityprofilesinvessels 391
Bloodflowincapillaries 392
Positiveclearance 394
Negativeclearance 396
Masstransportinthemicrocirculation 399