…close to reality

Obstetrical medicine background

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SIMone™

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Illustrations Holger Vanselow 2008

1 Thephysiologicalcourseofbirth 5

1.1 Thebirthmechanismintheoccipito-anteriorposition 6

1.2 Levelofthefetus’headinthematernalpelvis 10

2 Documentingandmonitoringbirth 12

2.1 Documentingthecourseofbirth 12

2.1.1 Cardiotocography(CTG) 13

2.1.2 Fetalscalpbloodanalysis(FSBA) 16

3 Vaginal-operativedeliverymethods 17

3.1 Forceps 18

3.2 Forcepsdelivery 19

3.2.1 Techniqueofforcepsdelivery,i.e:transverseforcepsdelivery 19

3.3 Vacuumextractor 24

3.4 Vacuumextractiondelivery 24

3.4.1 Techniqueforvacuumextraction 25

4 Amniotomy 28

5 Episiotomy 29

6 Caesareansection 30

7 Contractionstimulationforinefficientcontractions 31

8 Inhibitionofcontractions(tocolysis) 32

9 Analgesiaandanesthesiaduringdelivery 33

10 Assessmentofthenewborn 35

11 Literature 36

TableofContents

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5

Anormally-progressingbirthproceedsspontaneouslyandissubjecttoacomplex

interplayofactions.

Thephysiologicalcourseofbirthcanbeclassifiedinthreestages:

1. Dilatativestage

2. Expulsivestage

3. Placentalstage

Dilatativestage

Thedilatativestagecommenceswiththefirstlaborcontractionsandconcludes

withcompletedilationoftheosuteri.Itisdividedintoalatentphaseandan

activephase.Thelatentphasecomprisesthetimeofthecontinuousshortening

ofthecervixduringtheabsenceof,oronlyminimal,openingoftheosuteri.

Theactivephasecomprisesthecompleteopeningoftheosuteri,withincreasing

contractileactivity.

Expulsive stage

Theexpulsivestagecommenceswithcompleteopeningoftheosuteri

(approx.10cm)andconcludeswiththebirthoftheinfant.Itisdividedintoan

earlyexpulsivestageandapushingstage.

Placental stage

Theplacentalstagecomprisesthedetachmentandexpulsionoftheplacenta

1 Thephysiologicalcourseofbirth

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Thebirthmechanismintheoccipito-anteriorpositioniscomprisedofthefol-

lowingphases:

• Commencementmechanism

• Progressionmechanism

• Expulsionmechanism

• Externalrotation

Duringthebirth,thefetalheadgoesthrougharangeofmotions

(presentationandpositionalchanges):

• 1.Turning=Flexion

• 2.Turning=Rotation

• 3.Turning=Deflexion

• 4.Turning=Rotation

Asthebodypartofthefetusproceedstoincreasinglylowerpartsofthebirth

canal,itmustadapttothevariableanatomyofthefemalepelvis.

Forthisreason,duringthecommencementmechanism,aheadthatislocatedin

theoccipito-anteriorpositionwithflexionmustmovetoatransversepresentation

inthetransverseovalpelvicentrance:withthesagittalplaneproceedingtrans-

verselyorinasomewhatslanteddirection(Ill.1a–c).

Duringtheprogressionmechanism,theheadmovesdeeper(progression)intothe

pelviccavity.Inordertoadapttotheroundtransverseovalpelvicinlet,thehead

bends.Thusthe1stturn(=flexion)iscompleted.Inthisphase,thesmallfonta-

nelisatthedeepestpointoftheanteriorportion,theso-calledcentralpresenta-

tion(Ill.1d–f).

Whentheheadreachesthepelvicfloor,the2ndturn(=rotation)follows:the

headturns90°andtheanteriorocciputturnsforward(towardsthesymphysis).

Nowthesagittalplaneisinastraightdiameter(Ill.1g–i).

1.1 Thebirthmechanismintheoccipito-anteriorposition

7

Subsequently,duringtheexpulsivemechanismtheheadmustmoveinanarc

aroundthesymphysis.The3rdturn(=deflexion)follows;thatis,theheadmakes

anextendingmovement,thuschangingitspresentation.Theinfant’sfaceis

facingthedeliverytable(Ill.1j–l).

Immediatelyafteritsexpulsionfromthepelvis,theheadmakesanother90°turn,

theso-called4thturn(=rotation),sothatthesagittalplaneisonceagaintrans-

verse,meaningthattheinfant’sfaceisfacingtheupperthighofthemother

(Ill.1m–r).

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Thelevelofthefetalheadwithinthematernalpelvisisdeterminedbymeansof

external(LeopoldandZangemeistermaneuver)andinternal(vaginal)examination.

Uponinternalexamination,thesagittalplaneandthefontanelarepalpated.The

centralpresentationisassessedbydeterminingcentimeters(-4to+4cmaccording

toDeLee)above(+)orbelow(-)theinterspinalline(thevirtuallinebetweenthe

IschialSpines).Inaddition,theinterspinalplateau,accordingtoDeLee,alsode-

monstratesthe0-station(=0cm).Iftheanteriorocciputhasenteredthepelvis

duringanterior-occipitaladjustment,theheadisinthecentreofthepelvis,mea-

ningthatthebonycentralpresentationcanbepalpatedbetween0and+3cm.The

infant’sheadisonthefloorofthepelviswhenthecentralpresentationispalpable

at+4cm.Theplaneofpassageisthenattheleveloftheinterspinalplane(0cm).

Inaddition,thelevelcanbedeterminedbasedontheparallelplanesystemaccor-

dingtoHodge.Theindividualparallelplanesare4cmapart,whicharedefinedas

follows,fromcranialtocaudal:

•Theupperuterinesagittalplane,whichrunsfrom

theupperedgeofthesymphisistothesacralpromontory.

•Theloweruterinesagittalplane,whichrunsfrom

theloweredgeofthesymphisistothesacrum.

•Theinterspinalplane,theorientationpoints

ofwhichareindicatedbytheIschialSpines.

•Thepelvicfloorplane.

TheAmericanCollegeofObstetriciansandGynecologistshaspublishedaclassifi-

cationofthelevels,thusdefiningtheinterspinalplaneat0cmandrunningfrom5

to+5cm.Thismeansthatat+5cm,thefetalheadisvisibleinthevaginalintroitus.

1.2 Levelofthefetalheadinthematernalpelvis

11

Ill. 2 Levels according to DeLee and Hodge

Upper uterine sagittal plane

-4 cm, lower uterine sagittal plane

0 cm, interspinal plane

+4 cm, pelvic floor plane

-3 cm -2 cm -1 cm

+1 cm +2 cm +3 cm

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2 Documentationandmonitoringofthebirth

Itisoftheutmostimportancethatthebirthbemeticulouslydocumented,not

onlyonforensicgrounds.Thismeansthatanexpertthirdpartycanbeadequately

informedbythedocumentationaboutthecasehistory,thepregnancyandthe

courseofthebirthsothathe/sheisabletoassessthemeasurestakenduringthe

birth,retrospectively.

2.1 Documentingthecourseofbirth

Thepartogramisusedtodocumentthecourseofbirthanddeterminewhether

ornotitwasnormal.Thepartograminvolvesagraphicrepresentationinwhich,

accordingtotheFriedmannmethod(1954),thewidthoftheosuteriandthe

levelofthecentralfetalpresentation(ordinates)versusthetime(abscissa)are

delineated(s.Ill.3).

Thepatient’shistory,detailsofthepresentpregnancy,theCTGand,ifrelevant,

theORreportscompletethepartogram,yieldingasounddocumentationofthe

courseanddevelopmentofthebirth.

Ill. 3 Partogram modified according to Friedmann

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2.1.1 Cardiotocography(CTG)

Thecardiotocographycomprisesacontinuousrecordofthefetalheartrateand

thepatternofcontractions.Patternsoffetalheartratearedocumentedtoreflect

bothnormalanddeliteriouschangestothefetalenvironmentinutero.The

tocogramdeterminesthefrequency,duration,formandregularityofthecontrac-

tions.

InordertobeabletointerprettheCTGcorrectly,thedeliveryassistantmustpos-

sessacomprehensiveknowledgeofthesubject.RepeatedCTGtrainingisrequired

inordertoreinforcethisknowledge

Fetal heart rate

•Basicrate(basalrate,baseline)inbeatsperminute[Bpm]:

Thisshowsthemeanvalueofthefetalheartrateduringanextendedperiod.

•Floatingline:Thisshowsthelong-termmeanoscillationtrend.

•Normocardia:Normalbasicrate.

•Tachycardia:Riseinbasicrate>10minutes>150Bpm1

•Bradycardia:Dropinbasicrate>3minutes<100Bpm1

•Oscillation(variability):Showsthefluctuationsinthecurveofthefetalheart

rateinrelationtothebasicrate.

•Oscillationamplitude(bandwidth/variability)[Bpm]:Thisspecifiesthe

differencesinthefetalheartratebetweenmaximumandminimumfluctuations.

•Oscillationrate:Thisistherateoffluctuationaroundthefloatingline.

•Accelerations:Riseinfetalheartrate.

•Deceleration:Dropinfetalheartrate.

- Earlydecelerations(DIPI):Adropinfetalheartratebeginswhenacon-

tractioncommencesandthefetalheartratereachesitslowestpointatthe

peakofthecontraction.Attheendofacontraction,thefetalheartrate

returnstoitsbasiclevel.

- Latedecelerations(DIPII):Thedropinfetalheartratedoesnotoccuruntil

1 Because the reference values vary internationally, applicable guidelines and recommendations should always be followed.

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afterthepeakofthecontractionandthefetalheartratereturnstoits

basiclevelaftertheendofacontraction.

- Variabledecelerations:Theseappearinavarietyofforms,duration,levels

andrelationshiptocontractionsintermsoftime.

- Atypicalvariabledecelerations:Variabledecelerationsthatdemonstrate

thefollowingcharacteristics:

Aftertheendofacontraction,thereturntobasicrateisgradual.

Afteracontraction,thebasicratelastsforanextendedperiod.

Nooscillationsaredemonstratedduringdeceleration.

Thebasicrateremainslow.

Thereisnoprimaryorsecondaryriseinfetalheartrate.

Biphasicdeceleration.

- Sinusoidalpattern:Thebasicratedemonstratesafluctuationoveran

extendedperiod,intheformofsinuswaves

15

Ill. 4 Acceleration in the fetal heart rate

Ill. 5 Variable deceleration in the fetal heart rate

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2.1.2 Fetalscalpbloodanalysis(FSBA)

Thefetalscalpbloodanalysis,whichisalsoreferredtoasamicro-bloodevaluation

(MBU)isusedtomonitorthefetus.Afterdisinfectionoftheexternalgenitalia,depen-

dinguponthestageofbirth,afewdropsofbloodaretakenfromtheemerging

partofthefetus,eitheramnioscopicallyorelsewiththeaidofaspeculum.Itis

requiredthatthereisabrokenoropenamnioticsacandanosuterithatisopen

atleast2to3cm.InadditiontothepHvalue,thepCO2,thepO

2,bicarbonateand

thebaseexcesscanalsobedetermined.

IndicationsforcarryingoutanFSBAarethefollowing:

• ContinuedsuspiciousorpathologicalCTGpattern

• ExtremelyprotractedcourseofbirthwithsuspiciousCTGpattern

• GreenamnioticfluidwithsuspiciousorpathologicalCTG

ContraindicationsforcarryingoutanFSBAarethefollowing:

• Aclosedoronlyslightly-openosuteri

• ApathologicalCTGonthesecondtwin

• Prematurity<34WOP

• Terminalbradycardia

• MaternalinfectionssuchasHIV,HBV,HCV,HGVandHSV

• Thefirstappearingpartoftheinfantisonthepelvicfloor

• Fetalcoagulationdisturbances

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3 Vaginal-operativedeliverymethods

Vaginal-operativedeliverymethodsincludevacuumextractionandforceps

extraction.

Thefollowingconditionsmustbefulfilledforavaginal-operativedelivery:

• Completeopeningoftheosuteri

• Exactdeterminationofthelevelofthefetalhead

(inthecentreofthepelvis/onthepelvicfloor)

• Exactdeterminationofthepositionanddirectionofthefetalhead

• Brokenoropenamnioticsac

• Desirableproportionsbetweenthefetalheadandthematernalpelvis

• Theinfantmustbealive

• Themothermustbeawareofthesituation

• Thebirthassistantmustbeanexpertinthetechnique

• Sufficientanalgesiaandanesthesia

Inordertobeabletocarryoutavaginal-operativedelivery,theabove-listed

conditionsmustbemetandthefollowingaretypicalindications:

• Fetalemergencysituation(hypoxia,asphyxia)=pathologicalCTG

• Maternalemergency,suchas,forexample,eclampsia,epilepticattack

• Exhaustionofthemother

• Weakcontractions

• Suspensionofthebirthingprogressduringthepushingperiod

• Cardiopulmonaryorcerebrovascularillnessinthemother

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3.1 Forceps

Therearevarioustypesofobstetricforceps.Allconsistoftwobranchesthatmeet

eithertransverselyorparalleltothehub

Eachbranchoftheforcepsconsistsofforcepsblades,aforcepsshankandafor-

cepshandle.Theforcepsbladesconsistoftworibsandapoint.Thebladesofthe

forcepsdemonstratesthecurvatureoftheheadandpelvis.Theclosureisatthe

shankoftheforceps.Theforcepsdeliveryistheclassicmethodforrapidlyconclu-

dingadelivery.

Ill. 7a – e a Shute forceps, b Bamberger forceps, c Laufe forceps, d Naegele forceps, e Kielland forceps

a

b

c

d

e

19

Onceoneoftheabove-mentionedconditionsisfulfilled,thefollowingprepara-

tionsmustbemade:

• Themothermustbepositioned(dorsosacralposition)

• Contractionsmaybestimulatedusingmedication

• Theurinarybladdermustbeemptied

• Thesurgeon’shandsandthevulvamustbedisinfected

• Vaginalexamination:osuteriwidth,positionandpresentationof

thefetalhead

• Analgesia,forexampleepiduralanesthesiaorpudendalblock

• Episiotomyifnecessary

3.2.1 Techniqueofforcepsdelivery,i.e:transverseforcepsdelivery

• Assemblyoftheforceps

• Holdtheclosedforcepsinthecorrectpositioninfrontofthevulvaasthe

headoftheinfantistobegrasped(Ill.6a).

• Withthelefthand,introducetheleftforcepsbranchintotheleftsideofthe

mother(Ill.6b):

- Placetwotofourfingersoftherighthandintothespacebetweenthe

vaginalwallandthefetalheadtoprotectthematernalsofttissue.The

thumbremainsoutside.

- Theleftforcepsbranch,heldwiththelefthand,isheldhangingperpendi-

cularlyinfrontofthevulva.

- Placetheextendedthumboftherighthandonthebackriboftheleft

forcepsblade.

3.2 Forcepsdelivery

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- Withthelefthand,allowtheleftforcepsspoontocomebetweenthefetal

headandtheprotectingrighthandovertherightsideofthemotherand

slideitgentlyintothevaginabyallowingthehandletodropdownward.

• Now,usetherighthandtointroducetherightforcepsbranchintotheright

sideofthemother(Ill.6d):

- Toprotectthematernalsofttissue,introducetwotofourfingersofthe

lefthandbetweenthevaginalwallandthefetalhead.Thethumbremains

outside.

- Holdtherightforcepsbranch,heldwiththerighthand,perpendicularlyin

frontofthevulva.

- Theextendedthumbofthelefthandliesonthebackriboftheright

forcepsspoon.

- Withtherighthand,allowtherightforcepsbladetocomebetweenthe

fetalheadandtheprotectinglefthandovertheleftsideofthemother

andslideitgentlyintothevaginabyallowingthehandletodropdown-

ward.Therightforcepsbranchliesovertheleftforcepsbranch.

• Theforcepsisnowclosed(Ill.6e).

• Itisvitalthatacheckiscarriedouttodeterminethatnomaternalsofttissue

isbeinggraspedalongwiththefetalheadandtobesurethattheforcepsis

properlypositionedonthefetalhead.Todothis,holdtheforcepswithone

handwhileusingtheothertochecktheforceps’positioninthevagina.

• Thencarryoutatestpull:Withthelefthand,grasptheforcepshandlefrom

above.Inordertopreventexcessivepressureonthefetalhead,theleftindex

fingercanbepushedbetweenthetwoforcepshandles2.Withtherighthand,

checktheloweringofthefetalheadduringcontraction.

2 Other methods used in order to prevent excessive pressure on the fetal head include:• Placing a rolled towel between the two forceps handles or neck parts.• Placing the middle finger of the right hand between the two neck parts.

21

a

b

c

d

e

f

g h

Ill. 6a – h Placing the forceps and extraction (using a transverse forceps as an example)

• Holdingtheforceps(Ill.6g):Withthelefthand,holdtheforcepshandlesfrom

aboveandwiththerighthand,holdaBuschhookfromabove.Inorderto

avoidplacingexcessivepressureonthefetalhead,placeeitherarolledtowel

orafingerbetweenthehandlesortheneckoftheforceps.

• Pull:Thenpull,synchronouslywiththecontraction,inthedirectionofthe

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forcepshandles(Ill.7a),untilthecentralpositionofthevulvaisvisible.This

meansthatthehypomochlionhasarrivedatthebottomedgeofthepubic

bonejoint.

• Lifttheforcepshandlesastheheaddescends(Ill.7b).Nowthesurgeongoes

totheleftsideofthemotherandholdstheforcepsinhis/herrighthand,

transverselyoverthepubis(Ill.6h)

• Ifanepisiotomyisnecessary,thisisnotcarriedoutuntilthefetalheadis

positionedonthepelvicfloor.

• Protecttheperineumwiththelefthand

Ill. 7a A pull synchronously with the contraction in the direction of the handles of the forceps (a transverse forceps is used in the example)

Ill. 7b Lifting the forceps handles (a transverse forceps is used in the example)

23

• Withtherighthand,lifttheforcepshandletowardsthemotherinorderto

leadtheheadaroundthepubicbone(Ill.7c).

• Theforcepsmayberemovedpriortoorafterthebirthofthehead.The

formermayhelptodiminishperinealtrauma.Theinfantisextractedinthe

normalmannerafterwards.

Ill. 7c Lifting the forceps handle towards the mother’s abdomen (a transverse forceps is used in the example)

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3.3 Vacuumextractor

Therearevarioustypesofvacuumextractors:metalvacuumextractorsandsili-

convacuumextractors,eachwithdifferentcharacteristics.Thecommonfeatureis

thatthevacuumextractorisplacedontheleadingfetalpart,withvariousope-

ningdiameters:40mm,50mmand60mm.

3.4 Vacuumextractiondelivery

Vacuumextractionisanalternativemethodofspeedingupabirth.

Onceoneoftheconditionsspecifiedatthebeginningofthischapterhasbeenmet,

thefollowingpreparationsshouldbecarriedout:

• Positionthemother(dorsosacralposition)

• Ifnecessary,stimulatecontractionswithmedication

• Emptytheurinarybladder

• Disinfectthehandsofthesurgeonandthevulva

• Vaginalexamination:osuteriwidth,positionandpresentationofthefetal

head

• Analgesia,forexampleepiduralanesthesiaorpudendalblock

Ifoneofthefollowingsituationsisobserved,vacuumextractioniscontraindicated3:

• Faceorforeheadpresentation

• Prematurity<34WOP

• ActivebleedingfromtheFSBAincisionsite

• Knownthrombocytopenia

• Absenceofbirthprogressduringpushing

3 Please also read the user information with regard to conditions and contraindications.

25

3.4.1 Techniqueforvacuumextraction

• Spreadthelabiaforpresentationofthevaginalintroitus

• Choosethelargestpossiblevacuumextractor

• Introducethevacuumextractor(Ill.8):

- Introducethemetalvacuumextractortransversely

- Compressandintroducethesiliconvacuumextractor

• Placethevacuumextractor:

- Withthefetalheadrotatedtowardsthecentralposition

- Ifthepositionalchangeisincomplete,placeitinwhatistobetheleading

area

• Checktobesurethatnomaternalsofttissueisbeinggraspedalongwiththe

extractorandthatthevacuumextractorhasbeenplacedproperlyaroundthe

fetalhead.

• Graduallyincreasevacuum4force

• Afterthefirststageofthevacuum,checkoncemoretobesurethatnomater-

nalsofttissueisbeinggrasped.

• Increasevacuumforcegraduallyuntilavacuumof0.6–0.8kg/cm²hasbeen

reached4

4 Please note the applicable manufacturer’s specifications that are enclosed with the pump with regard to the gradual pressure decrease.

Ill. 8 Introducing a vacuum extractor, with a metal vacuum extractor in the example

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a b

c

• Thencarryoutatestpull:Holdthehandleofthevacuumextractorwithone

handandtouchthecentralpositionwiththeother,checkingtobesurethat

theinfantisfollowingthepull.

• Extraction:Pullingiscarriedoutsimultaneouslytopushingbythemother,in

synchronywiththecontractions,withincreasinganddecreasingforce.This

allowsthefetalheadtoremaininpositionwithoutslidingbackinwhena

contractionsubsides.

• Pull(Ill.9a–c):Thepulling,synchronouswithcontractions,followsin

accordancewiththeparabolaofthebirth(inlinewiththepelvis).

Ill. 9a – c Pulling direction during vacuum extraction with occipito-anterior position

4 Please note the applicable manufacturer’s specifications that are enclosed with the pump with regard to the gradual pressure decrease

27

• Possiblyacolleaguecanprovideadditionalassistancebyperforminga

Kristeller’smaneuver.

• Ifnecessary,anepisiotomycanbecarriedoutoncethefetalheadisonthe

pelvicfloor.

• Onehandprotectstheperineum.

• Afterthebirthofthehead,graduallydecreasethevacuumofthevacuum

extraction.

• Thevacuumextractorcanberemovedduringthedeliveryofthebody.

Theheaddeformationcausedbythismethod(caputsuccedaneum)willsubside

within12–24hours.

Thevacuumextractormayonlybeplacedtwice.Afterithasbeenplacedtwice,

thebirthmustbeterminatedwithaforcepsor,ifnecessary,byCaesareansection.

Thisisbecause,ontheonehand,theheaddeformationthathasbeencreated

makesfurtherfixationofthevacuumextractormoredifficultandontheother

hand,intracranialpressurefluctuationsmightleadtocerebralhemorrhage.

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4 Amniotomy

Breakingtheamnioticsacwithaninstrumentmayshortenthelatentphaseof

labor.Thedeliveryassistantormidwifecanbreaktheamnioticsacusingasterile

amniotichook,aspiralelectrodeorsurgicalforceps

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Anepisiotomytakesthestressofftheperineumandmayshortenthesecond

stageoflabor.Italsotakesthepressureoffthefetalhead.

Indicationsforanepisiotomyarethefollowing:

• Extremelytautsofttissue

• Unfavorablepresentationofthefetalhead(deflexionposition,occiput

posterior)

• Threatenedperinealrupture

• Shorteningoftheexpulsiveperiodduetofetalhypoxia

• Forcepsdelivery(notimperative)

• Vacuumextraction(notimperative)

• Breechpresentation

Therearethreedifferenttypesofepisiotomy:

1. Mediolateralepisiotomy:

Theincisioniscarriedoutcommencingexactlyattheanteriorcommissure,at

anangleof45°inalateraldirection

2. Medianepisiotomy:

Commencingattheposteriorcommissure,thedeliveryassistantseparatesthe

connectivetissuepartoftheperineuminthecentretowardstheanus.

3. Lateralepisiotomy:

Theincisioniscarriedout1–2cmbesidethemidlineoftheposteriorcom-

missuretowardstheTuberossisischii.

Thechoiceofincisionalwaysdependsupontheindications.Forexample,

amediolateralepisiotomyispreferredforavacuumextraction.

5 Episiotomy

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Anabdomino-operativeterminationofthepregnancyorbirthisindicatedin

thefollowingcases:

• PossiblyinthecaseofapreviousCaesareansection

• Onbreechpresentationinaprimiparaormultiplepregnancy

• Transversepresentation

• Pelvicdeformities

• Suspecteddisproportionbetweenfetalheadandmaternalpelvis

• Threateneduterinerupture

• Placentalabruption

• Protracteddurationofbirth

• Threatenedfetalhypoxia

• Infectionsinthemother,suchasHerpesgenitalis

• Placentapraeviatotalis(marginalis)

• Eclampsia

• Amnioticfluidembolism

• Umbilicalcordprolapse

• HELLPsyndrome

6 Caesareansection

31

Themedicalstimulationofcontractionsusingoxytocinisindicatedinsituations

whereastrikinglyslowprogressofbirthoracessationofprogressisobserved,

causedbyweakcontractionswithoutindicationsofahindrancetothebirth.5

Situationsthatwouldprohibitvaginalbirthcontraindicatetheuseofoxytocin.

Thesecanbe:

• Birthmechanismhindrance

• Pathologicalanatomyofthepelvis

• Placentapraevia

• Vasapraevia

• Prolapseofumbilicalcord

• Statuspost-myomectomywithtransgressionoftheuterinecavity

• Invasivecervicalcarcinoma

7 Contractionstimulationforinefficientcontractions

5 Because there are various dosing schedules for the application of oxytocin, it is important that the applicable guidelines and recommendations and the manufacturer‘s information be taken into consideration when this medication is used.

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8 Inhibitionofcontractions(tocolysis)

Inhibitionofprematurecontractionsusingmedicationisindicatedinorderto

effecttheprolongationofapregnancyifthereisariskofthreatenedpremature

birth.

Excessivelystrongcontractionsduringbirthcanalsobeanindicationfortocolysis.

Intrauterinehyperactivitycanresultinaworseningofthefetalcondition.

Sustainedcontractionsleadingtoanacuteoxygendeficitmustbecorrected

bywayofemergencytocolysis.Emergencytocolysisisanadditionalaidinthe

monitoringofmaternalcirculatoryparameters.Polysystole(excessivecontraction

rates)alsorequiresintervention.

Basedontheminimalhalf-lifetimeofoxytocininplasma(approx.3min.)and

intheuterinetissue(approx.15min.),anoxytocininfusioniseasytomanage.

Shoulduterinehyperactivityoccurduringsuchtreatment,thedosagecanbe

decreased.

Generalcontraindicationsfortocolysisarethefollowing:

• Fetalmaturity

• Fetalindicationsforterminationofthepregnancy

• Maternalindicationsforterminationofthepregnancy

• Intrauterineinfections

• Intrauterinefetaldeath

Medicationsthatinhibitcontractions(tocolytics)are:

• ß-sympathomimetics,suchasphenoterol

• Magnesium,suchasmagnesiumsulphate

• ProstaglandinsynthesisinhibitorssuchasIndomethacin

• Calciumantagonistssuchasnifedipin

• Oxytocinantagonists

• NO-donatorssuchasnitroglycerin

33

Thechoiceoftocolyticdepends,firstofall,uponwhatislicensedinagivencoun-

tryandsecondlytheindicationsandcontraindicationsofagivenmedication.

9 Analgesiaandanesthesiaduringdelivery

Analgesiaandanesthesiacontrolpain,resultinginarelaxationofthepelvicfloor

musclesandthusmakingthedeliverymoretolerable.

Medicaltreatmentforthepainofbirthiseffectedbymeansofsystemicanalgesia

andregionalanesthesia.

Inadditiontoanalgesicssuchasopiatesandopioids,whichareusedforsystemic

analgesiaforthealleviationofpain,spasmolyticsandsometimesnitrousoxide

areused.

Othertypesoftreatmentforpainincludeacupuncture,transcutaneouselectrical

nervestimulation(TENS),homeopathicmedicationsandthepracticeofrelaxation

techniques.

Thetypeofregionalanesthesia,aslistedbelow,usedtocontrolthepainofbirth

dependsupontheindication,meaningthebirthassistancesituationandthe

reasonforthepain.

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• Epidural anesthesia (EA, peridural anesthesia):

Forepiduralanesthesia,eitherthesingle-injectiontechniqueorthecatheter

techniqueisusedtoadministeralocalanestheticand/oropioidintothe

epiduralcavityattheleveloftheintervertebralspaceL2/3orL3/4.

• Spinal anesthesia:

Forspinalanesthesia,eitherthesingle-injectiontechniqueorthecatheter

techniqueisusedtoinjectalocalanestheticand/oropioidintotheepi-

duralcavityattheleveloftheintervertebralspaceL2/3orL3/4intothe

subarachnoidspace.

• Combined spinal-epidural anesthesia:

Thisprocedureinvolvesacombinationofspinalanesthesia(usingthe

single-injectiontechnique)andepiduralorepiduralanesthesia(usingthe

cathetertechnique).Afterpuncturingtheepiduralcavityatthelevelofthe

intervertebralspaceL2/3orL3/4,aspinalneedleisintroducedthrough

thecannulaandthesubarachnoidspaceispunctured.Aftertheinjection

ofalocalanestheticand/oropioidsandtheremovalofthespinalneed-

le,theanesthetistplacesandfixestheepiduralcatheterintheepidural

cavity.

• Pudendal block:

Forthecontrolofperinealdilationpainandtorelaxthepelvicfloor

muscles,thepudendalnerveanditsbranchesareblockedbytheinjection

ofalocalanestheticfromthevaginaonbothsidesofthepudendalnerve

region.

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10 Assessmentofthenewborn

VirginiaApgardevelopedasystemthatentailedthestandardizationoftheassess-

mentofnewborns.

Theso-calledAPGARscoreiscomprisedofthefollowingfivecomponents:

1. Heartrate

2. Breathing

3. Reflexes

4. Muscletone

5. Skincolor

Eachcomponentisratedafter1,5and10minutesbywayofapointssystem

(0to2points):ahealthynewborninfantshouldscorebetween7and10points.

IftheAPGARscoreisbetween3and6,theinfantindicatesamildtomoderate

depressivestate.AnAPGARscoreof0to2indicatesaseriousdepressivestate.

Atthesametime,thisindicatestheneedformeasuresthatcanbetakeninorder

tosupportthenewborninadaptingtoitsnewcircumstancesafterbirth.

Criterion 0points 1 point 2 points

Heart rate none <100Bpm >100Bpm

Breathing none slow,irregular regular,crying

Reflex response and sucking reflex

none decreased crying

Muscle tone limp sluggishflexion activemovement

Skin color pale,bluetrunkrosy,

extremitiesbluerosy

Tab. 1 APGAR score

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11 Bibliography

Thefollowingliteraturesourceswereusedinthepreparationofthishandbook:

• AmericanCollegeofObstetriciansandGynecologists:Intrapartumfetalheart

ratemonitoring.ACOGTechnicalBulletinNo132.Washington,DC(1989)

• CunninghamFG,LevenoKJ,BloomSL,HauthJC,GilstrapIIILC,WenstromKD:

WilliamsObstetrics,22ndedition,McGraw-Hill(2005)

• DiedrichK,HolzgreveW,JonatW,SchneiderKTM,WeissJM:Gynäkologieund

Geburtshilfe,Springer-Verlag,Berlin,Heidelberg(2000)

• DudenhausenJW,PschyrembelW:PraktischeGeburtshilfemitgeburtshilf-

lichenOperationen,19.,fullyrevisededition,WalterdeGruyter,Berlin,New

York(2001)

• GoerkeK,StellerJ,ValetA:KlinikleitfadenGynäkologie,Geburtshilfe,

6.Auflage,Urban&FischerVerlag,München,Jena(2003)

• HalleH:MitUnterdruckodermitZange?GynäkologieundGeburtshilfe4,

18-20(2006)

• LeitliniederDeutschenGesellschaftfürGynäkologieundGeburtshilfe:

AbsoluteundrelativeIndikationenzurSectiocaesareaundzurFrageder

sogenanntenSectioaufWunsch.AWMFRegister-Nr.015/024(2006)

• LeitliniederDeutschenGesellschaftfürGynäkologieundGeburtshilfe:

Vaginal-operativeEntbindungen.AWMFRegister-Nr.015/023(2007)

• LeitliniederDeutschenGesellschaftfürGynäkologieundGeburtshilfe:

37

AnwendungdesCTGwährendSchwangerschaftundGeburt.

AWMFRegister-Nr.015/036(2007)

• MaedaK.FIGONews:ReportoftheFIGOStudyGroupontheAssessmentof

NewTechnology.Evaluationandstandardisationoffetalmonitoring.

IntJGynaecolObstet59,169–173(1997)

• NICHD(NationalInstituteofChildHealthandHumanDevelopment).Electro-

nicfetalheartratemonitoring:Researchguidelinesforinterpretation.Re-

searchPlanningWorkshop.AmJGynaecolObstet177,1385–1390(1997)

• RoothG,HuchA,HuchR.FIGONews:Guidelinesfortheuseoffetalmonito-

ring.IntJGynaecolObstet25,159–167(1987)

• RoyalCollegeofObstetriciansandGynaecologists:TheUseofElectronicFetal

Monitoring.Evidence-basedClinicalGuidelineNumber8(2001)

• SchneiderH,HussleinP,SchneiderKTM:DieGeburtshilfe,3.Auflg.,

Springer-Verlag,Berlin,Heidelberg(2007)

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Notes

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