Contents& & & 1.! Ultrasound&basics& 1! 2.! Image&generation& 15!

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1 A l i n e press é

2 % % % Contents& & & 1. Ultrasound&basics& What,is,ultrasound?, Ultrasound,probes,send,and,receive,ultrasound, How,does,ultrasound,behave,travelling,through,tissue?, 4 Attenuation) 4 Reflection) Gain, Depth, Ultrasound,frequency,dictates,resolution,and,depth, Doppler,and,flow, Image&generation& Probe,choice, Sonographer,and,patient,position, Use,enough,gel, Identify,structure,of,interest, Understanding,the,ultrasound,image, 21 Field)of)view) 23 Orientation)of)structures)relative)to)probe)position) Adjust,depth, Adjust,gain, Cleaning,the,machine,and,the,patient, Troubleshooting,tips, 29 iii%

3 Bedside Ultrasound - Level 1 3. Artifacts& Common,artifacts, Shadowing,artifact, 31 Advantage) 32 Disadvantage) Enhancement,artifact, 34 Advantage) 34 Disadvantage) Mirror,image,artifact, 36 Advantage) 36 Disadvantage) Reverberation,artifact, 37 Advantage) Troubleshooting,tips, &Dyspnea& Probe,choice, Patient,position,and,scanning,technique, Lung,sliding, A,lines, B,lines, Lung,profiles, 47 Clinical)relevance)of) A )lines)b) A )profile) 47 Clinical)relevance)of) B )lines)b) B )profile) 47 Clinical)relevance)of) A )+) B )lines)b) AB )profile) Posterolateral,chest, 49 Clinical)relevance)B)Posterolateral)chest)exam) Troubleshooting,tips, &Undifferentiated&hypotension& Probe,choice, Patient,position,and,scanning,technique, Left,ventricular,function, 55 Clinical)relevance)B))LV)function) Right,to,left,ventricular,diameter,ratio, 60 iv%

4 Clinical)relevance)B)Pulmonary)embolism) Pericardial,effusion, 61 Clinical)relevance)B)Tamponade) Volume,status,and,the,IVC, 62 Clinical)relevance) Additional,ultrasound,assessments,for,hypotension, Troubleshooting,tips, &Trauma& Probe,choice, Patient,position,and,scanning,technique, The,eFAST,algorithm, 71 Question)1:)Does)the)patient)have)free)intraabdominal)or)pelvic)fluid?) 72 Question)2:)Does)the)patient)have)a)hemopericardium?) 78 Question)3:)Does)the)patient)have)a)hemothorax?) 79 Question)4:)Does)the)patient)have)a)pneumothorax?) Troubleshooting,tips, Abdominal&aortic&aneurysm& Probe,choice, Patient,positioning,and,scanning,technique, Clinical,relevance,$,Abdominal,aortic,aneurysm, Troubleshooting,tips, &Cholecystitis& Probe,choice, Patient,position,and,scanning,technique, 93 Technique)#1:)The)subcostal)sweep) 93 Technique)#2:)The)XB7)approach) 94 Technique)#3:)The)posterolateral)approach) Ultrasound,appearance,of,the,gallbladder, Clinical,relevance:,Cholecystitis, 98 1.)Gallstones) 98 2.)Sonographic)Murphy)sign) )Thickness)of)anterior)gallbladder)wall) 101 v

5 Bedside Ultrasound - Level 1 Summary)B)clinical)relevance)for)cholecystitis) Troubleshooting,tips, &Kidney&injury& Probe,choice, Patient,position,and,scanning,technique, 107 Imaging)the)kidney)in)the)coronal)plane) 107 Imaging)the)kidney)in)the)transverse)plane) 109 Imaging)the)bladder)in)the)sagittal)plane) 110 Imaging)the)bladder)in)the)transverse)plane) Clinical,relevance,$,Obstructive,causes,of,kidney,injury, 112 Hydronephrosis) 112 Distended)postBvoid)bladder) Troubleshooting,tips, Deep&venous&thrombosis&of&the&lower&limb& Probe,choice, Patient,position,and,scanning,technique,$,Common,femoral,vein,119 Clinical)relevance)B)DVT)in)the)common)femoral)vein) Patient,position,and,scanning,technique,$,Popliteal,vein, 124 Clinical)relevance)B)DVT)in)the)popliteal)vein) Troubleshooting,tips, Ectopic&pregnancy& Probe,choice, Patient,position,and,scanning,technique, 129 Imaging)the)uterus)in)the)transverse)plane) 129 Imaging)the)uterus)in)the)sagittal)plane) The,appearance,of,an,intra$uterine,pregnancy, Clinical,relevance,$,Ectopic,pregnancy, Troubleshooting,tips, 134 Index& 135 References& 139 vi%

6 Chapter 4. Dyspnea 4.#Dyspnea# Case#scenario:# A# 70# year5old# woman# presents# herself# to# your# clinic# complaining#of#dyspnea.#she#is#too#short#of#breath#to# provide# a# useful# history.# Her# respiratory# rate# is# 40# breaths/min,#her#oxygen#saturation#is#80%,#and#she#is# tachycardic# with# normal# blood# pressure.# On# auscultation,#there#is#poor#air#entry#bilaterally.# Impression:#Dyspnea#NYD.#Consider#common#causes.# Commoncausesofdyspneacanberecognizedbyultrasoundexaminationof the chest. This chapter reviews the technique for diagnosis of pneumothorax,interpretationoflungartifacts,andidentificationofpleural effusions.#

7 Bedside Ultrasound Level Probe#choice# Bothlowandhighfrequencyprobescanbeusedforthisapplication. A B C Figure'4.1'Low'and'high'frequency'probes'that'can'be'used'for'assessing' the'patient'with'dyspnea.' A.Alowfrequencyphasedarrayprobe. B.Alowfrequencycurvilinearprobe. C.Ahighfrequencylinearprobe.Redcircledenotesorientationmarker.

8 Chapter 4. Dyspnea 4.2. Patient#position#and#scanning#technique# The patient should lie supine or be in bed. Scan the anterior fourthtofifthribinterspaceintheanterioraxillaryline. A B Figure'4.2'Scanning'technique'for'imaging'the'anterior'chest.'' Theanteriorchestisimagedbilaterallywithalinearprobeinthemid= clavicularline(a)andanterioraxillaryline(b).theorientationmarkerpoints cephalad.redcircledenotesorientationmarker. Video'4.1'Scanning'technique'with'lateral'rocking'motion.' Thelateralrockingmotionoftheprobeimprovesthesensitivityforlocating pathology(lichtenstein,2010).redcircledenotesorientationmarker.view videoonlineatbedsideultrasoundlevel1.com

9 Bedside Ultrasound Level Lung#sliding# Duringrespiration,the parietal and visceral pleuraslide over one another. This horizontal pleural movement during respiration is observed on an ultrasoundimageandiscalledlung#sliding(lichtensteinetal.,1995). Characteristics#of#lung#sliding## The area deep to the pleural line sways side@to@side with the patient sbreathing Thehyperechoic(white)pleurallinemovesor shimmers Clinical#relevance#of#lung#sliding# #Pneumothorax# A pneumothorax is a collection of air between the parietal and visceral pleura. Air in the pleural space prevents the contact between the pleurae and therefore prevents lung sliding. In all cases of pneumothorax, lung slidingwillbeabsentinthescannedareaovertheanteriorchestofasupine patient. Therefore normal lung sliding confidently rules out pneumothorax (Kirkpatricketal.,2004;Lichtensteinetal.,2005;Nobleetal.,2007;Pietteet al.,2013). rib shadow pleural line rib shadow Video'4.2'Presence'of'lung'sliding' on'the'anterior'chest'using'a' linear'probe.' Thehyperechoic(white)pleural line shimmers,thusillustrating lungsliding.accordingly,this patientdoesnothavea pneumothorax.redcircledenotes orientationmarker.viewvideo onlineat bedsideultrasoundlevel1.com #

10 Chapter 4. Dyspnea Importantly, the absence of lung sliding suggests# but# is# not# specific for a pneumothorax because there are other conditions in which lung sliding is absent or hard to detect. These conditions include pleural adhesions, atelectasis, apnea, unilateral bronchial intubation, and extremely shallow rapidbreathing(asthma)(lichtenstein,2010). pleural line rib shadow Video'4.3'Absence'of'lung'sliding' on'the'anterior'chest'using'a' linear'probe.' Notethatthepleurallinedoesnot shimmer orslidelaterally. Therefore,thispatientmayhavea pneumothorax.redcircledenotes orientationmarker.viewvideo onlineat bedsideultrasoundlevel1.com When the absence of lung sliding is observed, a pneumothorax can be confirmed by detecting a lung# point. The lung point is an ultrasound landmarkspecificforapneumothorax(lichtensteinetal.,2000). Tolookforalungpoint,startscanningtheanteriorchestofasupinepatient inwhomyouhavedetectedtheabsenceoflungsliding.graduallyscanover the chest posterolaterally. A lung point is defined by the alternating presence and absence of lung sliding between two ribs as the patient breathes.thelungpointcorrespondstothatareaoverthechestwallwhere the partially deflated lung moves into the ultrasound field of view during inspirationandthenoutagainduringexpiration.

11 Bedside Ultrasound Level 1 # Video'4.4'Scanning'technique'for' imaging'a'lung'point'using'a'linear' probe.' Redcircledenotesorientation marker.viewvideoonlineat bedsideultrasoundlevel1.com pleural line Video'4.5'Lung'point'on' posterolateral'chest'using'linear' probe.' Notethelungslidingcomingand goingfromtherightofthescreen. Redcircledenotesorientation marker.viewvideoonlineat bedsideultrasoundlevel1.com

12 Chapter 4. Dyspnea 4.4. # A #lines# An A #lineartifactisahyperechoic(white)horizontallinearisingatregular intervalsfromthepleuralline.an A lineartifactisproducedwhenscanning the anterior chest of a patient with normal lungs or in a patient with diseasedlungswithoutinterstitialdisease(e.g.obstructiveairwaysdisease) (Lichtenstein,2010). Characteristics#of# A #lines# Horizontalhyperechoic(white)lines Evenlyspacedthroughouttheultrasoundfield Immobile pleural line A lines Figure'4.3' A 'lines'in'a'normal'lung.'' Anteriorchestscanwithalinear probe.redcircledenotesorientation marker.

13 Bedside Ultrasound Level # B #lines# A B # line artifact is a hyperechoic (white) vertical line arising from the pleuralline.a B lineisanon@specificartifactproducedwithanydiseaseof the pulmonary interstitium including pneumonia, pulmonary edema, interstitialfibrosis,andacuterespiratorydistresssyndrome.threeormore B linesbetweentworibshadowsareconsideredabnormal(lichtensteinet al.,1998). Characteristics#of# B #lines# Vertical,comet@shapedhyperechoic(white)lines Originateatthepleuraandextendtothefar@fieldoftheultrasound screen Movewiththepleura Eliminate A lines pleuralline B lines Video'4.6.' B 'lines'in'a' diseased'lung.'' Anteriorchestscan(witha phasedarrayprobeinthe cardiacsetting)displaying vertical B linesthatoriginate atthepleuraandextendto thefar=field.redcircle denotesorientationmarker. Viewvideoonlineat bedsideultrasoundlevel1.com

14 Chapter 4. Dyspnea 4.6. Lung#profiles# Clinical#relevance#of# A #lines#5# A #profile# If you see lung sliding with A lines on bilateral anterior chest exams, the patient is defined as having an A # profile.# Patients presenting with an A profile and dyspnea generally have chronic obstructive pulmonary disease (COPD)orasthmaexacerbation.Patientswithan A profile,dyspnea,anda deep venous thrombosis (DVT) are likely to have a pulmonary embolism (Lichtensteinetal.,2008). Clinical#relevance#of# B #lines#5# B #profile# If you see lung sliding with B lines on bilateral anterior chest scans, the patientisdefinedashavinga B #profile.dyspneicpatientspresentingtothe emergency room with a B profile generally have cardiogenic pulmonary edema(lichtensteinandmeziere,2008). However,theinterpretationoflungprofilesmustalwaysbedoneincontext oftheclinicalimpression.forexample,apatientpresentingwitha B profile in association with fever, rigors, cough, and productive sputum, likely has bilateralpneumoniaandnotcardiogenicpulmonaryedema. Clinical#relevance#of# A #+# B #lines#5# AB #profile# Ifonesideoftheanteriorchesthas A lineswhiletheothersidehas B lines thepatientissaidtohavean AB # profile.#patientspresentingwithan AB profile and dyspnea are likely to have pneumonia as the cause of their dyspnea(lichtensteinandmeziere,2008).

15 Bedside Ultrasound Level 1 Table'4.1'Lung'profiles'and'common'associated'pathologies'in'outpatients' presenting'with'dyspnea.' Lung%profile% Pathology% COPD% A #lines# A #lines# Asthma% Pulmonary%embolism% (if%dvt%present)% A #profile# B #lines# B #lines# Cardiogenic% pulmonary%edema% B #profile# Pneumonia% A #lines# B #lines# AB #profile#

16 Chapter 4. Dyspnea 4.7. Posterolateral#chest# The posterolateral chest is examined for pleural effusions and lung consolidation. Characteristics#of#the#posterolateral#chest#exam# Diaphragmappearsasahyperechoic(white)line,concavecaudally Normallungappearsasa curtain #signsweepingintothefieldasthe diaphragmdescends Pleural effusion appears as an anechoic (black) area above the diaphragm Lung consolidation appears asa hypoechoic (grey) structure above thediaphragm Clinical#relevance#5#Posterolateral#chest#exam# Patients with dyspnea, a normal anterior chest exam (bilateral A lines), no DVT, and an unilateral pleural effusion or consolidation, likelyhavepneumonia(lichtensteinandmeziere,2008) Patientswithleftventriculardysfunction,a B profile,andbilateral pleural effusions likely have congestive heart failure (Lichtenstein andmeziere,2008) Pleural effusions with hyperechoic (white) floating particles or septaearelikelytobeexudative(yangetal.,1992) Ultrasoundcanbeusedtosafelyguideathoracentesis(Barnesetal., 2005;Jonesetal.,2003) Video'4.7'Scanning'technique'for' imaging'a'pleural'effusion'or'lung' consolidation'over'the'left' posterolateral'chest'using'a'phased' array'probe.'' Redcircledenotesorientation marker.viewvideoonlineat bedsideultrasoundlevel1.com

17 Bedside Ultrasound Level 1 Video'4.8'Normal'lung' revealed'by'a'posterolateral' chest'scan'with'a'phased' array'probe'in'the'cardiac' setting.' Asthediaphragmdescends caudally,thelungentersthe right=sidefieldofview.thisis termedthe curtain sign.red circledenotesorientation marker.viewvideoonlineat bedsideultrasoundlevel1.com Video'4.9'Large'pleural' effusion'revealed'by'a' posterolateral'chest'scan' with'a'phased'array'probe'in' the'cardiac'setting.' Thepleuraleffusionis cephaladtothediaphragm andappearsanechoic (black).redcircledenotes orientationmarker.view videoonlineat bedsideultrasoundlevel1.com Figure'4.4'Lung' consolidation'revealed'by'a' posterolateral'chest'scan' with'a'phased'array'probe' in'the'cardiac'setting.' Theconsolidatedlungisa hypoechoic(grey)structure. Redcircledenotes orientationmarker. liver cephalad caudad pleural effusion diaphragm liver lung cephalad caudad liver diaphragm consolidated lung caudad cephalad

18 Chapter 4. Dyspnea 4.8. Troubleshooting#tips# To#detect#a#pneumothorax#in#a#supine#patient,#be# sure#to#examine#the#anterior#chest.#this#is#because# the#pneumothorax#will#accumulate#anteriorly.# Beware# that# a# lung# point# will# not# be# found# in# a# tension# pneumothorax# because# the# lung# is# completely# collapsed# in# this# condition# and# therefore#does#not#contact#the#chest#wall.# In#cachectic#patients#with#a#protruding#rib#cage,#it# is#difficult#to#establish#adequate#contact#between# a# linear# probe# and# the# chest# wall.# This# difficulty# can# be# overcome# by# turning# the# probe# in# the# transverse#plane#so#that#it#fits#between#the#ribs,#or# by#using#a#microconvex#probe.# If# lung# sliding# is# difficult# to# identify# with# a# low# frequency# probe,# use# a# linear# high# frequency# probe#instead.# Case#closed:# The#70#year5old#woman#who#presented#herself#to#your# clinic#complaining#of#dyspnea#has#clinical#evidence#of# congestive# heart# failure.# She# is# found# to# have# a# B # profile# on# lung# ultrasound.# Diuretic# is# administered# and#the#patient#is#hospitalized.# #