The 5-Minute Clinical Consult 2014, Standard

1631 Pages·2013·22.773 MB·English

by  Baldor, Robert A.;Domino, Frank J.;Grimes, Jill A

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The 5-Minute
Clinical Consult
220134
22ND EDITION
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ADVISORY BOARD David Drajpuch, MSN, CRNP
Faculty,FamilyHealthNursePractitioner
FAMILY MEDICINE Program
UniversityofPennsylvaniaSchoolofNursing
Jonathan Bertman, MD
NursePractitioner,Cardiology
ClinicalAssistantProfessorofFamilyMedicine
Children’s HospitalofPhiladelphia
TheAlpertMedicalSchoolofBrownUniversity
Philadelphia,Pennsylvania
President,AmazingChart.com,Inc.
President,AfraidToAsk.com,Inc.
June Treston, MSN, CRNP
HopeValley,RhodeIsland
AssociateProgramDirector
Karen L. Maughan, MD FamilyHealthNursePractitionerProgram
UniversityofPennsylvaniaSchoolofNursing
AssociateProfessorofFamilyMedicine
Philadelphia,Pennsylvania
DepartmentofFamilyMedicine
NursePractitioner,EmergencyMedicine
UniversityofVirginia
CooperUniversityMedicalCenter
Charlottesville,Virginia
Camden,NewJersey
INTERNAL MEDICINE
Rebecca M. Wolf, BSN, RN, MSN, FNP
Eric J. Alper, MD MayoClinic
ProfessorofMedicine Rochester,Minnesota
MedicalDirector,InpatientEMR
UMassMedicalSchool/UMassMemorialHealthCare
PHARMACY
Worcester,Massachusetts
Michele L. Matthews, PharmD, CPE, BCACP
Erik Garcia, MD
AssistantProfessorofPharmacyPractice
AssistantProfessor
MassachusettsCollegeofPharmacyandHealth
DepartmentofFamilyMedicineandCommunityHealth
SciencesUniversity
UniversityofMassachusettsMedicalSchool
ClinicalPharmacySpecialistinPainManagement
Worcester,Massachusetts
BrighamandWomen’s Hospital
Nancy Kubiak, MD Boston,Massachusetts
AssociateProfessor
InternalMedicine PHYSICIAN ASSISTANT
UniversityofLouisville
Louisville,Kentucky Nancy McLaughlin, MPAS, PA-C
ClinicalAssistantProfessor
NURSE PRACTITIONERS CollegeofPharmacyandHealthSciences
PhysicianAssistantProgram
Eileen F. Campbell, MSN, CRNP
MercerUniversity
AssociateProgramDirector
Atlanta,Georgia
FamilyHealthNursePractitionerProgram
UniversityofPennsylvania
Philadelphia,Pennsylvania
FamilyNursePractitioner
DirectorofClinicalResearch
AdvocareHeightsPrimaryCare
HaddonHeights,NewJersey
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The 5-Minute
Clinical Consult
220134
Editor-in-Chief
FrankJ.Domino,MD
Professor
Pre-doctoralEducationDirector
DepartmentofFamilyMedicineandCommunityHealth
TheUniversityofMassachusettsMedicalSchool
Worcester,Massachusetts
22ND EDITION
Associate Editors
RobertA.Baldor,MD
Professor
Vice-Chairman
DepartmentofFamilyMedicineandCommunityHealth
TheUniversityofMassachusettsMedicalSchool
Worcester,Massachusetts
JeremyGolding,MD
Professor
DepartmentsofFamilyMedicineandObstetrics
andGynecology
TheUniversityofMassachusettsMedicalSchool
QualityOfficer
DepartmentofFamilyMedicineandCommunityHealth
UniversityofMassachusettsMemorialHealthCare–
HahnemannFamilyHealthCenter
Worcester,Massachusetts
JillA.Grimes,MD,FAAFP
ClinicalInstructor
DepartmentofFamilyMedicine
TheUniversityofMassachusettsMedicalSchool
Worcester,Massachusetts
UniversityofTexasHealthServices
Austin,Texas
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My good friend and mentor, Sanjiv Chopra, tells the story of Charlie Plumb, a Vietnam War pilot who was
shot down, parachuted, and became a prisoner of war. Later in life, he met and thanked the person who
“packed his parachute.’’ Many people have given us support and guidance, helped us in ways we could
never have foreseen would result in our current careers.
This year’s editorial team wishes to dedicate The 5-Minute Clinical Consult 2014 to these people; those
who spurred us on long before there were degrees and titles gracing our names. Thank you for packing
our parachutes.
“Anything worth doing is worth doing right!’’ This phrase was my mother’s mantra, frequently uttered as
she calmly ripped out one of my imperfect, hastily sewn seams, and then smoothly ironed, pinned, and
restitched the piece. Whether it was domestic crafts, school homework, or volunteer projects, I heard
these words each time I approached that critical frustration point where I was about to quit caring about
quality and simply finish as quickly as possible. Although my mom is no longer around to remind me in
person, her message remains etched in my heart and drives my actions, especially as a clinician. Follow
up on that slightly abnormal lab. Ask your patient about her nutrition. Take that extra 5 minutes, and look
up the latest evidence-based diagnostic tests or treatment. Anything worth doing is, indeed, worth doing
right. Thanks, Mom!
–JILLGRIMES,MD,FAAFP
My vision of becoming a family doctor was almost obscured by so many subspecialty mists in medical
school.Fortunately,IfoundguideswhoselightsIfollowed,andwhotaughtmetolightmyownlamp.Iowea
permanentdebttoJackMedalie,MD,andthefacultyofthefamilymedicinecenteratCaseWesternReserve
Medical School in the mid-80s. They and my mentors and role models in residency and fellowship at the
University of Rochester/Highland Hospital Family Medicine residency taught me to think critically, to listen
carefully to what patients were saying, and also to what they were not saying. These lessons helped me
comeintomyownasafamilydoctor,anditisintheirnamesthatIsharewhatIknowwithmystudentsnow.
–JEREMYGOLDING,MD
David Seeley was my high school AP biology teacher. He challenged my class to reach beyond what we
ever thought we were capable of—an example was the time I received a grade on a lab assignment that
was less than zero! I was stunned. I was convinced I was the best student in that class and although I
may have been, it was clear I could always do better. Such a grade brought me to a new level of thinking
about achievement (and humility!). I have carried this and other such lessons from this great teacher with
me throughout my education and career. Although Mr. Seeley passed away a few years ago, his legacy
lives on through the profound impact he had on the lives of many young people in Barre, Vermont.
–ROBERTBALDOR,MD
Mary Grosso smoked, gave me my first taste of beer, used a colorful vocabulary, and taught me to play
poker; in her view, a grandmother’s role. In my youth, I was shy and easily intimidated. Mary helped start a
textiles workers union and was, to my young brain, someone who did not let the constraints of the day
hold her back. My mom and dad’s love and support, my brother’s guidance and mentoring, and the other
Mary in my life (who helped teach me to cook; still one of my favorite hobbies) all developed my character.
But, my path to medicine came with challenges that took a great deal of determination to get past. Many
taughtmescience;Marytaughtmeself-confidence,tonotlettheconstraintsofthedayholdmeback.Her
determination helped many who followed live better lives; a legacy all of us in health care strive to provide.
–FRANKJ.DOMINO,MD
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PREFACE
(cid:2)
“Successisnotthekeytohappiness; FREEPointofCareCME:1/2hourCMECreditforeverydigital
Happinessisthekeytosuccess. search
Ifyoulovewhatyouaredoing,youwillbesuccessful.’’ (cid:2)200+diagnosticandtreatmentalgorithms
(cid:2)
Full-colorimagesandvideosforproceduresandtreatment
—ALBERTSCHWEITZER (cid:2)
DrugdatabasefromAtoZ
Iam the most fortunate person I know. Even as a salaried aca- (cid:2)Morethan1,300patienthandoutsinEnglishandSpanish
demicfamilydoctor,Ireceivemorefinancialincomethan95% (cid:2)
ICD-10Codes(Websiteonlyforthisyear;inboth,printand
ofthepeopleintheworld.Additionally,Ihavetheesteemofmy
online,startingin2014,whenICD-10becomesmandatory)
otherspecialtypeersinmedicine,theincrediblerelationshipswith
mypatients,andtheintellectualfuninbeingchallengedeachday Evidence-basedhealthcareistheintegrationofthebestmedical
toblendsciencewithinterpersonalcommunicationtohelpothers informationwiththevaluesofthepatientandyourskillasaclinician.
livetheirdaysinabetterway. WehaveupdatedourEBMcontentanditsvisibility,soyoucanfocus
AlbertSchweitzerwasatheologian,musician,imprisonedmis- onhowtobestapply.
sionary,philosopher,andphysician.Incrediblyintelligentandinsight- TheHealthMaintenance1-pagesummarieshavebeenupdated
ful,heusedhisgiftstomaketheworldabetterplace.Istandinawe throughDecember2012andarebasedontheUSPreventiveSer-
andamhumbled.So,wheneverIgetdiscouragedbythenextform vicesTaskForcerecommendations.
tocompleteorcodetoenter,IneedtorememberhowfortunateI The Algorithm section includes both diagnostic and treatment
am,and,likeSchweitzer,Igettousemygiftstohelpothers.Like algorithms.Thiseasy-to-usegraphicmethodhelpsyouevaluatean
Isaid,we,ashealthcareproviders,arelucky,andinSchweitzer’s abnormal finding and prioritize treatment. They are also excellent
view,happyand,therefore,successful. teachingtools,sosharethemwiththelearnersinyouroffice.
WelcometoThe5-MinuteClinicalConsult2014.Oureditorial Pleasetrytheonlineandmobileversionsatwww.5minuteconsult.
teamhasagaincollaboratedwithhundredsofauthorstobringyou com.Your30-dayaccessisfreewithbookpurchase(seeinside
this comprehensive and current resource whose goal is to assist the front cover), allowing you to quickly reference the 5-Minute
youandyourpatients. whereverneeded.Includedareover900topicsonaneasy-to-use
Thishighlyorganizedcontent,bothinprintandonline,provides interface allowing smooth maneuverability between topics, algo-
youwith: rithms,images,videoprocedures,andmore,aswellasextratopics
(cid:2) notinthebook.
Fast,intuitivesearchfunctionalityprovidingyouwithanswersin
<30seconds Welcome to The 5-Minute Clinical Consult 2014. Our edito-
(cid:2) rial team values your observations, so please drop me an e-mail
Currentevidence-baseddesignationshighlightedineachtopic’s
andshareyourthoughts,suggestions,andconstructivecriticismat:
text
(cid:2) [email protected].
ArevisedandupdatedHealthMaintenancesection
(cid:2)Morethan900topics FRANKJ.DOMINO,MD
January1,2013
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EVIDENCE-BASED MEDICINE
WHATISEVIDENCE-BASEDMEDICINE? Positivepredictivevalue(PPV):Percentofpositivetest
resultsthataretrulypositive;thePPVforawomanaged50–59
Rememberwhenweusedtotreateveryotitismediawithan- isapproximately22%.Thatistosaythatonly22%ofabnormal
tibiotics?Theserecommendationscameaboutbecausewe screeningmammogramsinthisgrouptrulyidentifiedcancer.The
appliedlogicalreasoningtoobservationalstudies.Ifbacteria other78%arefalsepositives.
causeanacuteotitismedia,thenantibioticsshouldhelpitresolve YoucantellMLonly1outof5abnormalmammogramscorrectly
sooner,withlessmorbidity.Yet,whenrigorouslystudied(viaasys- identifycancer;the4arefalsepositives,buttheonlywaytoknow
tematicreview),wefoundlittlebenefittothisintervention. whichmammogramiscorrectistodofurthertesting.
The underlying premise of evidence-based medicine (EBM) is
The corollary of the PPV is the Negative predictive
theevaluationofmedicalinterventions,andtheliteraturethatsup-
value(NPV),whichisthepercentofnegativetestresultsthat
ports those interventions, in a systematic fashion. EBM hopes to
aretrulynegative.
encouragetreatmentsproventobeeffectiveandsafe.Andwhen
The PPV and NPV tests are population dependent, while the
insufficient data exists, it hopes to inform you on how to safely
SensitivityandSpecificityarecharacteristicsofthetest,andhave
proceed.
little to do with the patient in front of you. So when you receive
EBMusesasendpointsofrealpatientoutcomes;morbidity,mor-
anabnormallabresult,especiallyascreeningtestlikemammogra-
talityandrisk.Itfocuseslessonintermediateoutcomes(boneden-
phyorPSAvalue,understandtheirlimitsbasedontheirPPVand
sity)andmoreonpatientconditions(hipfractures).
NPV.
Implementing EBM requires 3 components: The best medical
TreatmentInformationisalittledifferent.Indiscerning
evidence,theskillandexperienceoftheprovider,andthevaluesof
the statistics of randomized, controlled trials of interventions,
thepatients.Shouldthispatientbescreenedforprostatecancer?
firstconsideranexample.TheScandinavianSimvastatinSurvival
Itdependsonwhatisknownaboutthetest,onwhatyouknowof
Study(4S)(Lancet.1994;344[8934]:1383–1389)foundusing
itsbenefitsandharms,yourabilitytocommunicatethatinformation,
simvastatininpatientsathighriskforheartdiseasefor5years
andthatpatient’sinformedchoice.
resultedindeathsin8%ofpatientsvs.12%ofthoseonplacebo;
ThisbookhopestoaddressthefirstEBMcomponent,providing
this results in a relative risk of 0.70, a relative risk reduction
you access the best information in a quick format. While not ev-
(RRR)of33%,andanumberneededtotreatof25.
erytestortreatmenthasthislevelofdetail,manyoftheincluded
interventionshereusesystematicreviewliteraturesupport. Therearetwowaysofconsideringthebenefitsofanintervention
Thelanguageofmedicalstatisticsisusefultointerpretingthe withrespecttoagivenoutcome.Theabsoluteriskreduction(ARR)
conceptsofEBM.Belowisalistoftheseterms,withexamplesto isthedifferenceinthepercentofpeoplewiththeconditionbefore
helptaketheconfusionandmysteryoutoftheiruse. andaftertheintervention.Thus,iftheincidenceofMIwas12%for
the placebo group and 8% for the simvastatin group, the ARR is
Prevalence:Proportionofpeopleinapopulationwhohave
4%(12%−8%=4%).
adisease(intheUS,0.3%(3in1,000)peopleovertheage50
TheRRRreflectstheimprovementintheoutcomeasapercent-
havecoloncancer).
age of the original rate and is commonly used to exaggerate the
Incidence: How many new cases of a disease occur in a
benefitofanintervention.Thus,iftheriskofMIwerereducedbysim-
populationduringanintervaloftime;forexample,“theestimated
vastatinfrom12%to8%,thentheRRRwouldbe33%(4%/12%=
incidenceofcoloncancerintheUSis104,000in2005.’’
33%);33%mayappearbetterthan4%,the4%thatreflectsthe
Sensitivity(Sn):Percentofpeoplewithdiseasewhotest
trueoutcome.
positive;formammography,thesensitivityis71–96%.
ARR is usually a better measure of clinical significance of an
Specificity (Sp): Percent of people without disease who
intervention. For instance, in one study, the treatment of mild hy-
testnegative;formammography,thespecificityis94–97%.
pertensionwasbeenshowntohaveaRRRof40%over5years
NowsupposeyousawML,a53-year-oldwoman,foraHealth
(40%fewerstrokesinthetreatedgroup).However,theARRwas
Maintenance visit and ordered a screening mammogram and the
only 1.3%. Because mild hypertension is not strongly associated
reportdemonstratesanirregularareaofmicrocalcifications.Sheis
withstrokes,aggressivetreatmentofmildhypertensionyieldsonly
waitinginyourofficetoreceivehertestresults;whatcanyoutell
asmallclinicalbenefit.Don’tconfuseRelativeRiskReductionwith
her?
RelativeRisk.
Thesetestsrefertocharacteristicsofpeoplewhoareknownto
Absolute (or attributable) risk (AR): The percent of
havedisease(sensitivity)orthosethatareknownnottohavedisease
peopleintheplaceboorinterventiongroupwhoreachanend
(specificity). What you have is an abnormal test result. To better
point; in the simvastatin study, the absolute risk of death was
explainthisresulttoML,youneedtoknowthepositivepredictive
8%.
value,tohelpusinterpretthetestresults.
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x (cid:2) (cid:2) (cid:2) Evidence-Based Medicine
Relativerisk(RR):Theriskofdiseaseofthosetreatedor Publication bias occurs when research is not published;
exposedtosomeintervention(i.e.,simvastatin)dividedbythose thisisoftenwhenastudyfindsdatathatdoesnot supportan
intheplacebogrouporwhowereuntreated. intervention. The motivation to publish information that “didn’t
—IfRR<1.0,itreducesrisk—thesmallerthenumber,the work’’islow.Itisestimatedthatupto40%ofallmedicalresearch
greatertheriskreduction. nevergetspublished.Sowhenyoureadofaninterventionthat
—IfRR>1.0,itincreasestherisk—thegreaterthenumber, “works,’’ wonder if other studies were done that did not show
thegreatertheriskincrease. benefitandwentunpublished.
Relative risk reduction (RRR): The relative decrease in Comparatorbiasoccurswhenresearchcomparesanin-
riskofanendpointcomparedtothepercentofthatendpoint terventiontoplacebo,whenplaceboisnotthestandardofcare.
intheplacebogroup. Knowing a new antibiotic is more effective than placebo for
Ifyouarestillconfused,justremembertheRRRisanoveresti- treating acute otitis media is not helpful if you typically use
mationoftheactualeffect. amoxicillin.
Why not release research comparing the new drug to the
Number needed to treat (NNT): This is the number of
standardofcare?Often,theresearchhasbeendone,andthe
peoplewhoneedtobetreatedbyaninterventiontopreventone
adverseoutcome.A“good’’NNTcanbealargenumber(>100) newdrugprovednobetter.Ifthisstudydoesnotgetpublished,
youhaveanexampleofpublicationbias.
ifriskofseriousoutcomeisgreat.Iftheriskofanoutcomeis
notthatdangerous,thenlower(<25)NNTsarepreferred. Selection bias involves either using a tool that does not
discriminate between populations selected or just reporting a
TheNNTshouldbecomparedtoasimilarstatistic,theNumber
justsubsetofstudyparticipantsfromastudy.Eitherwillresultin
NeededtoHarm(NNH).Thisisthenumberofpeoplewhohaveto
thedatabeingskewedbecauseitcanonlybeappliedtosmall
begiventreatmentbeforeoneexcesssideeffectorharmoccurs.
subsetofpeople.
WhentheNNTiscomparedtotheNNH,youandthepatientcan
Attrition bias and the concept of intention to treat.
judge whether the benefit of the intervention is great enough to
Attritionbiasiswhenresearchersdonotfullyacknowledgeand
outweightheriskofharm.
addresshowastudydealswithparticipantswhodonotadhere
totheresearchprotocolordropoutcompletely.Intentiontotreat
EVIDENCED-BASEDGRADING:
analysishopestodiminishattritionbiasbystatisticallyconsider-
To help you interpret diagnostic and treatment recommendations ingthenonadheringordroppedoutpatientsasunsuccessfully
withinThe5-MinuteClinicalConsult,wehavegradedthebestin- benefitingfromtheintervention.
formationwithinthetext,andhighlightedthiscontent. Commercial (funder) bias involves who paid for the re-
An“A’’grademeansthereferenceisfromthehighest-qualityre- search being done, and do they have a vested interest in the
source,likeasystematicreview.Asystematicreviewisasummary outcome.Despiteitssizeandscope,therecentJupiter trialon
of the medical literature on a given topic that uses strict, explicit treatinglow-riskadultswithastatinhasbeencalledintoques-
methods to perform a thorough search of the literature and then tion, as the company who funded the study makes the brand
provides a critical appraisal of individual studies, concluding in a namedrugusedinthestudyandtheleadauthorispartowner
recommendation.Themostprestigiouscollectionofsystematicre- oftheuniquetestemployedinthetrial.Thedatamaybeaccu-
viewsisfromtheCochraneCollaboration(www.cochrane.org). rate,butuntilthisisstudiedbylessvestedinterests,somefeel
A“B’’grademeansthedatareferencedcomesfromhigh-quality itsoutcomecannotbeclinicallyapplied.
randomizedcontrolledtrialsperformedtominimizebiasintheirout- Have you been annoyed how one week you learn of a ran-
come.Biasisanythingthatinterfereswiththetruth;inthemedical domized controlled trial that supports a treatment, to be followed
literature,itisoftenunintentional,butitismuchmorecommonthan the next week with a contradictory article? Statisticians have fig-
weappreciate.Inshort,alwaysassumesomedegreeofbiasexists ured out how to resolve this using something called a systematic
inanyresearchendeavor. review.
A“C’’ gradeimpliesthereferenceuseddoesnotmeettheAor Systematic reviews take all the literature on a topic, say
Brequirements;theyareoftentreatmentsrecommendedbycon- usingantibioticstotreatotitismedia,andcombinesthedatato
sensusgroups(liketheAmericanCancerSociety).Insomecases, determineifthesumofallthetrialstellsadifferentstorythan
theymaybethestandardsofcare.Butimplicitinagroup’srecom- any single trial. The large number of participants in this type
mendationisthebiasoftheauthororthegroupthatsupportsthe of research results in a much more statistically (and clinically)
reference.Forexample,theAmericanUrologicalSociety’s recom- significantconclusionthananysinglepaper.Wantmore?Check
mendationaroundscreeningforprostatecancermaybemotivated thisout:http://musculoskeletal.cochrane.org/what-systematic-
by their need for funding rather than patient outcomes. Compare review.
this to the recommendations of the US Preventive Services Task
Ameta-analysisisaquantitativesystematicreview,anddemon-
Force(www.ahrq.gov).
stratesitoutcomesintheformofaforestplot.Thebottomlinewith
interpretationofaforestplotislookforthediamondonthebottom.
BIAS:
IfitistoLEFToftheverticalline,itmeansriskofanoutcomewas
Biasisanythingthatinterfereswiththetruth.Therearemanytypes reducedbytheintervention.IfitisfullytotheRIGHT,thenriskof
ofbiasthatshouldbeconsideredbythepublishersofmedicalin- thatoutcomewasincreased.Andifthediamondtouchesthevertical
formation.Belowdescribesanumberofbiastypesthatoftenaffect line,itmeanstherewasnostatisticalinfluenceoftheintervention
ourcarewithoutusknowingitispresent: on the outcome. To understand these concepts better, here is a