Warm perineal compresses during the second stage of labor for reducing perineal trauma: A meta-analysis

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Warm

perineal

compresses

during

the

second

stage

of

labor

for

reducing

perineal

trauma:

A

meta-analysis

Giulia

Magoga

a

,

Gabriele

Saccone

b,

*

,

Huda

B. Al-Kouatly

c

,

Hannah

Dahlen

G

d

,

Charlene

Thornton

e

,

Marzieh

Akbarzadeh

f

,

Tulin

Ozcan

g

,

Vincenzo

Berghella

c a_Department_of_Medical,_Surgical_and_Health_Sciences,_University_of_Trieste,_Trieste,_Italy

b

DepartmentofNeuroscience,ReproductiveSciencesandDentistry,SchoolofMedicine,UniversityofNaplesFedericoII,Naples,Italy

c

DivisionofMaternal-FetalMedicine,DepartmentofObstetricsandGynecology,SidneyKimmelMedicalCollegeofThomasJeffersonUniversity,Philadelphia, PA,USA

d

SchoolofNursingandMidwifery,WesternSydneyUniversity,LockedBag1797,Penrith,NSW2751,Australia

e

CollegeofNursingandHealthSciences,FlindersUniversity,Adelaide,Australia

f_{Maternal-Fetal}_Medicine_Research_Center,_Shiraz_University_of_Medical_Sciences,_Iran

g_Division_of_{Maternal-Fetal}_Medicine,_Department_of_Obstetrics_and_Gynecology,_University_Hospitals_Cleveland_Medical_Center,_Case_Western_Reserve

University,Cleveland,USA

ARTICLE INFO Articlehistory: Received14March2019

Receivedinrevisedform30May2019 Accepted11June2019 Availableonlinexxx Keywords: Vaginaldelivery Secondstage Delivery Episiotomy Warmcompress Perinealtears ABSTRACT

Objective:Perinealtraumamayhaveanegativeimpactonwomen’slivesasithasbeenassociatedwith perinealpain,urinaryincontinenceandsexualdysfunction.Theaimofthissystematicreviewand meta-analysisofrandomizedcontrolledtrialswastoevaluatetheeffectivenessofwarmcompressesduringthe secondstageoflaborinreducingperinealtrauma.

Methods:ElectronicdatabasesweresearchedfrominceptionofeachdatabasetoMay2019.Inclusion criteriawererandomizedtrialscomparingwarmcompresses(i.e.interventiongroup)withnowarm compresses(i.e.controlgroup)duringthesecondstageoflabor.Typesofparticipantsincludedpregnant womenplanningtohaveaspontaneousvaginalbirthattermwithasingletoninacephalicpresentation. Theprimaryoutcomewastheincidenceofintactperineum.Meta-analysiswasperformedusingthe Cochrane Collaboration methodology with results being reported as relative risk (RR) with 95% conﬁdenceinterval(CI).

Results:Seventrials,including2103participants,wereincludedinthismeta-analysis.Womenassignedto the intervention group received warm compresses madefrom clean washcloths orperineal pads immersedinwarmtapwater.Thesewereheldagainstthewoman’sperineumduringandinbetween pushesinsecondstage.Warmcompressesusuallystartedwhenthebaby’sheadbegantodistendthe perineumorwhentherewasactivefetaldescentinthesecondstageoflabor.Wefoundahigherrateof intactperineumintheinterventiongroupcomparedtothecontrolgroup(22.4%vs15.4%;RR1.46,95%CI 1.22to1.74);alowerrateofthirddegreetears(1.9%vs5.0%;RR0.38,95%CI0.22to0.64),fourthdegree tears(0.0%vs0.9%;RR0.11,95%CI0.01to0.86)thirdandfourthdegreetearscombined(1.9%vs5.8%;RR 0.34,95%CI0.20to0.56)andepisiotomy(10.4%vs17.1%;RR0.61,95%CI0.51to0.74).

Conclusion:Warmcompressesappliedduringthesecondstageoflaborincreasetheincidenceofintact perineumandlowertheriskofepisiotomyandsevereperinealtrauma.

Introduction

Theincidenceofperinealtraumaaftervaginalbirthcanvary considerably,withbetween53–79%ofwomenexperiencingsome

typeofperinealtrauma[1].Mostareﬁrstandsecond-degreetears, whereasaround3.3%ofwomenhaveathird-degreetearandabout 1.1%haveafourthdegreetear[2].Severeperinealtears,though uncommon,mayhaveanegativeimpactinawoman’slifeasthey have been associated with perineal pain, urinary and fecal incontinenceandsexualdysfunction[1,2].Preventionofperineal trauma, and thirdand fourth-degreelacerations inparticular is therefore essential [1–19]. Different techniques have being reported to prevent perineal lacerations, including perineal

* Correspondingauthorat:DepartmentofNeuroscience,ReproductiveSciences andDentistry,SchoolofMedicine,UniversityofNaplesFedericoII,Naples,Italy.

E-mailaddress:gabriele.saccone.1990@gmail.com(G.Saccone).

https://doi.org/10.1016/j.ejogrb.2019.06.011

ContentslistsavailableatScienceDirect

European

Journal

of

Obstetrics

&

Gynecology

and

Reproductive

Biology

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massage[3],hands-ontechnique[4],Ritgen’smaneuver[5],useof lubricantgel[6]andwarmcompresses[7,2–19].

Objective

The aim of this systematic review and meta-analysis of randomizedclinicaltrials(RCTs)wastoevaluatetheeffectiveness ofwarmcompressesduringthesecondstageoflaborinreducing perinealtrauma.

Methods

Eligibilitycriteria,informationsources,searchstrategy

Thisreviewwasperformedaccordingtoaprotocoldesigneda prioriandrecommendedforsystematicreviewsofinterventions [20].Electronicdatabases(i.e.MEDLINE,Scopus,ClinicalTrials.gov, EMBASE, Sciencedirect, the Cochrane Library at the CENTRAL RegisterofControlledTrials,Scielo)weresearchedfrominception of each database to May 2019. Search terms used were the following text words: “cesarean,” OR “caesarean”, OR “warm compression”, OR “warm packs”, OR “warm compresses”, OR “secondstage”,OR“labor”,OR“labour”,OR“vaginaldelivery,”OR “perineum,”OR“perineal,”OR“episiotomy,”OR“perinealtrauma,” OR“perineal lacerations”, OR “perineal tears”, OR “postpartum pain,”OR“meta-analysis,”OR“meta-analysis,”OR“review,”AND “randomized,”OR“randomised,”OR“clinicaltrial.”Norestrictions forlanguageorgeographiclocationwereapplied.Inaddition,the referencelistsofallidentiﬁedarticleswereexaminedtoidentify studiesnotcapturedbyelectronicsearches.Theelectronicsearch andtheeligibilityofthestudieswereindependentlyassessedby three authors (GM, GS, CT). Disagreement was resolved by discussionwithaforthreviewer(HD).

Studyselection

We included all RCTs comparing warm compression (i.e. interventiongroup)withnowarmcompresses(i.e.controlgroup) duringthesecondstageoflabor.Warmcompresswasdeﬁnedasa moistwarmclothorpad.Typesofparticipantsincludedpregnant womenplanningtohaveaspontaneousvaginalbirthattermwith asingletonfetuswithacephalicpresentation.Applicationofwarm gelpadswereexcluded.Otherperinealtechniques, e.g.perineal massage, ﬂexion technique, Ritgen’s maneuver, hands-on or hands-poised were not included in this meta-analysis. Quasi randomizedtrialswerealsoexcluded.

Dataextractionandriskofbiasassessment

Theriskofbiasineachincludedstudywasassessedbyusingthe criteriaoutlinedintheCochraneHandbookforSystematicReviewsof Interventions.Sevendomainsrelatedtoriskofbiaswereassessed ineachincludedtrialsincethereisevidencethattheseissuesare associatedwithbiasedestimatesoftreatmenteffect:1)random sequence generation; 2) allocation concealment;3) blindingof participantsandpersonnel;4)blindingofoutcomeassessment;5) incompleteoutcomedata;6)selectivereporting;and7)otherbias. Reviewofauthors’judgmentswerecategorizedas“lowrisk”,“high risk”or“unclearrisk”ofbias.20_Only_two_trials_were_at_low_risk_of

bias(Figs.2and3).

Primaryandsecondaryoutcomes

Analysisweredoneusinganintention-to-treatapproach.The primaryoutcomewastherateofintactperineum(deﬁnedasno lacerations and no episiotomy). The secondary outcomes were perinealtraumanotrequiringsuturing,perinealtraumarequiring

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suturing,ﬁrst-second-third-fourth-degreeperineallacerations and third and fourth degree lacerationscombine, incidence of episiotomy

Threeauthors(GM,GS,CT)independentlyassessedinclusion criteria, risk of bias and data extraction. Disagreement was resolvedbydiscussionwithforthreviewer(VB).

Statisticalanalysis

Thedataanalysiswascompletedindependentlybytwoauthors (GSandCT)usingReviewManagerv.5.3(TheNordicCochrane Centre,CochraneCollaboration,2014,Copenhagen,Denmark).The completedanalyseswerethencompared,andanydifferencewas resolvedbydiscussion.Thesummarymeasureswerereportedas summaryrelativerisk(RR)orassummarymeandifference(MD) with 95% of conﬁdence interval (CI) using the random effects modelofDerSimonianandLaird.I-squared(HigginsI2₎_was_used_to

identifyheterogeneity.

The review was reported following the Preferred Reporting Item for Systematic Reviews and Meta-analyses (PRISMA)

statement[21].Beforedataextraction,thereviewwasregistered withthePROSPEROInternationalProspectiveRegisterof System-aticReviews(registrationNo.:CRD42018100564).

Results Studyselection

Seventrials,including2103participants[7,8,10,16–19],metthe inclusion criteria for this meta-analysis, (Fig.1, Table 1). Most studieshadalowriskofbiasinselectivereportingandincomplete outcomedataaccordingtotheCochraneCollaboration_’stool.No study was double blinded because this was deemed difﬁcult methodologically given the intervention. One trial blinded the assessorfortheperinealtrauma(Fig.2).Statisticalheterogeneity withinthetrialsrangedfromlowtohighwithanI2₌_87%_for_the

primaryoutcome.

All trials included pregnant women planning to have a spontaneousvaginalbirthattermwithasingletoninacephalic presentation.Womenassignedtotheinterventiongroupreceived

Table1

Characteristicsoftheincludedtrials.

Albers2005 Dahlen2007 Sohrabi2012 Mamuk2013 Vaziri2014 Terré-Rull 2014

Essa2016

Studylocation NewMexico,USA Sydney,Australia Iran Turkey Shiraz,Iran Barcelona, Spain

Damanhour, Egypt

Singleton Yes Yes Yes Yes Yes Yes Yes

Cephalic presentation

Yes Yes Yes Yes Yes Yes Yes

Gestationat enrollment (weeks)

Atterm Atleast36weeks NR Between37and 42weeks Between37and42 weeks NR Atterm Maternalage (rangeinyears)

Olderthan18years Olderthan16years 18-35years NR 18-35years Olderthan 18years

18to35years Otherinclusion

criteria

Healthy Anticipatedanormalbirth Livefetus,no underlying maternaldisease estimatedfetal weight<4000g Previuosvaginal delivery, estimatedfetal weightof2500– 4000g Livefetus, Hemoglobin level11mg/dl Lowor mediumrisk, spontaneous delivery Normal pregnancy,no perineal massage previous Samplesize* ₈₀₈₍₄₀₄_vs₄₀₄₎ ₇₁₇₍₃₆₀_vs₃₅₇₎ ₇₆₍₃₈_vs₃₈₎ ₆₀₍₃₀_vs₃₀₎ ₁₅₀₍₇₅_vs₇₅₎ ₁₃₂₍₆₆_vs₆₆₎ ₁₆₀₍₈₀_vs₈₀₎

Primaryoutcome Intactperineum Needforsuturing Perineal lacerationsand needforrepair

NR Painseverityand onsetofsexual activity Needfor suturing Perineal traumaand needtorepair Intervention group

Warmcompresses Warmcompresses Warmcompresses andRitgen’s maneuver

Warm compresses

Warmcompresses Warm compresses

Warm compresses Controlgroup Handsoff Standardcare Ritgen’smaneuver Standardcare Standardcare Standardcare Standardcare Timetostart

warmpacks

Activefetaldescent orwhenthefetal headwasvisible withauterine contraction

Whenthefetalheadbegan todistendtheperineum andthepatientwasaware ofastretchingsensation

NR Secondstageof labor

Secondstageoflabor Secondstage oflabor Secondstageof labor Timecompresses wereheldto perineum (beforeput againinto water) Applied continuouslyas possibleuntil crowning,during andbetween pushing Appliedduring

contractions,untildelivery

Duringandafter pushing

NR Betweenandduring contractions,forat least15minutesanda maximumof20 minutes Foratleast 10minutes, anda maximumof 30minutes Duringeach contraction Water temperatureof thejug NR 45-59C NR 60-70C 70C 45C 45-59C Timetokeep compressesin warmwater

NR Betweencontractions Duringandafter pushing

10-15minutes 12minutes NR Between contractions Howoftento

replacewaterin thejug

NR Every15minutesuntil deliveryorifthe temperaturedropped below45_C NR NR NR NR Every 15minutesorif the temperature droppedbelow 45_C NR,notreported. *

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warmcompressesmadefromcleanwashclothsorperinealpads immersedinwarmtapwater.Inoneofthetrialsamoistwarmand drywarmcompresswereused(onlydataforthemoistpackwas analyzed).Compresseswereheldagainstthepatient’sperineum duringsecondstageoflaborandchangedasneededtomaintain warmthandcleanliness.Warmcompressesusuallystartedwhen thebaby’sheadbegantodistendtheperineumorwhentherewas activefetaldescentinthesecondstageoflabor(Table1). Synthesisofresults

PrimaryandsecondaryoutcomeswerereportedinTable2.We foundahigherrateofintactperineumintheinterventiongroup comparedtothecontrolgroup(22.4%vs15.4%;RR1.46, 95%CI 1.22–1.74;Fig.3);ahigherrateofperinealtraumanotrequiring suturing (54.1%vs 47.1%; RR 1.15, 95% CI 1.07–1.24; Fig.4); no

differenceinﬁrstdegree(24.8%vs21.4%;RR1.22,95%CI0.93–1.60) orseconddegreetears(25.2%vs25.3%;RR1.00,95%CI0.86–1.15);a lowerrateofthirddegreetears(1.9%vs5.0%;RR0.38,95%CI0.22to 0.64),fourthdegreetears(0.0%vs0.9%;RR0.11,95%CI0.0to-0.86), thirdandfourthdegreetearscombined(1.9%vs5.8%;RR0.34,95% CI0.20to0.56)andepisiotomy(10.4%vs17.1%;RR0.61,95%CI0.51 to0.74).

Discussion Mainﬁndings

Our review of seven RCTs (n=2103) showed that warm compressesusedinthesecondstageoflaborwasassociatedwith an higher rate of intact perineum, and lower rate of perineal traumanotrequiringsuturing,andofepisiotomy.

Fig.2. Assessmentofriskofbias.(A)Summaryofriskofbiasforeachtrial;Plussign:lowriskofbias;minussign:highriskofbias;questionmark:unclearriskofbias.(B)Risk ofbiasgraphabouteachriskofbiasitempresentedaspercentagesacrossallincludedstudies.

Table2

Perinealoutcomes.

Albers2005 Dahlen2007 Sohrabi2012 Mamuck 2013 Vaziri2014 Terré-Rull 2014 Essa2016 Total RRorMD (95%CI) Intactperineum 94/404(23.3%) vs90/404 (22.2%) 13/360(3.6%)vs 17/357(4.8%) 21/38(55.3%) vs16/38 (42.1%) 13/30(43.3%) vs7/30 (23.3%) 29/75(38.7%) vs5/75(6.7%) 16/66(24.2%) vs25/66 (37.9%) 50/80(62.5%) vs2/80(2.5%) 236/1053(22.4%) vs162/1050 (15.4%) 1.46 (1.22to 1.74) Perinealtraumanot

requiringsuturing 321/404(79.5%) vs316/404 (78.2%) 77/360(18.7%) vs73/357 (18.6%) 14/38(39.5%) vs17/38 (44.7%) NR NR 47/66(71.2%) vs37/66 (56.1%) NR 513/948(54.1%) vs445/945 (47.1%) 1.15 (1.07to 1.24) Perinealtrauma requiringsuturing 83/404(20.5%) vs88/404 (21.8%) 283/360(78.6%) vs284/357 (79.6%) 24/38(63.2%) vs21/38 (55.3%) NR NR 19/66(28.8%) vs29/66 (43.9%) 26/80(32.5%) vs78/80 (97.5%) 435/948(45.9%) vs500/945 (52.9%) 0.87 (0.80to 0.94) Firstdegree 97/404(24.1%) vs89/404 (22.0%) NR 12/38(31.6%) vs18/38 (47.4%) NR NR 31/66(47.0%) vs12/66 (18.2%) 2/80(2.5%)vs 0/80(0%) 153/618(24.8%) vs132/618 (21.4%) 1.22 (0.93to 1.60) Seconddegree 70/404(17.3%) vs74/404 (18.3%) 150/360(41.7%) vs136/357 (37.8%) 5/38(13.2%) vs4/38 (10.5%) NR NR 14/66(21.2%) vs16/66 (24.2%) 0/80(0%)vs9/ 80(11.3%) 239/948(25.2%) vs239/945 (25.3%) 1.00 (0.86to 1.15) Thirddegree 3/404(0.7%)vs 2/404(0.5%) 15/360(4.2%)vs 31/357(8.7%) 0/38(0%)vs0/ 38(0%) NR NR 0/66(0%)vs2/ 66(3.0%) 0/80(0%)vs 12/80(15.0%) 18/948(1.9%)vs 47/945(5.0%) 0.38 (0.22to 0.64) Fourthdegree 0/404(0.0%)vs 4/404(1.0%) 0/360(0.0%)vs 0/357(0.0%) 0/38(0.0%)vs 0/38(0.0%) NR NR 0/66(0.0%)vs 0/66(0.0%) 0/80(0.0%)vs 4/80(5.0%) 0/882(0.0%)vs8/ 879(0.9%) 0.11 (0.01to 0.86) Severeperineal

trauma(third& fourthdegree) 3/404(0.7%)vs 6/404(1.5%) 15/360(4.2%)vs 31/357(8.3%) 0/38(0%)vs0/ 38(0%) NR NR 0/66(0%)vs2/ 66(3.0%) 0/80(0%)vs 16/80(20%) 18/948(1.9%)vs 55/945(5.8%) 0.34 (0.20to 0.56) Episiotomy 1/404(0.3%)vs 2/404(0.5%) 39/360(10.8%) vs41/357(11.5%) 0/38(0%)vs0/ 38(0%) 0/30(0%)vs 7/30(23.3%) 39/75(52.0%) vs68/75 (90.7%) 5/66(7.6%)vs 11/66(16.7%) 26/80(32.5%) vs50/80 (62.5%) 110/1053(10.4%) vs179/1050 (17.1%) 0.61 (0.51to 0.74) NR,notreported;RR,relativerisk;CI,conﬁdenceinterval.Dataarepresentedasnumbersintheinterventiongroupvsnumbersinthecontrolgroupwithpercentages.

*

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The study was limited by the low number of the included women,variationsintemperatureofthewater,timingandlength ofapplication andvariationsin techniqueusedinsecond stage management (i.e. Ritgens Maneuver). The temperature of the waterused wasof particularconcernas somestudiesreported temperaturesofupto70C.Therewasalsoinconsistencyinwhen andforhowlongthewarm packswereapplied,withsomejust appliedwhenthefetalheaddistendedtheperineumandothers appliedassoonassecondstagecommenced.Onlyonestudy[8] followedwomenuppostnatallytothreemonthsfollowingbirth. Implications

Morethanhalfofpregnantwomenexperienceperinealtrauma duringa vaginalbirth.Perinealtrauma canvary fromminorto majorperineallacerations,withanincidenceofthirdandfourth degree lacerations of 3.3% and 1.1% respectively [22,23]. It is importanttoprevent severeperinealtraumainordertoreduce blood loss, perineal pain,as well as urinary,bowel and sexual dysfunction.In this meta-analysis we evaluatedthe efficacyof warm compresses during the second stage of labor. Heat can producesomepositivetherapeuticeffectsleadingtodilatationof blood vessels and an increase of blood flow. Muscle spasm or tensionproduceslocalischemia; however,increasedbloodflow canreducethelevelofnociceptivestimulationandincreasethe clearanceofinflammatorymediators[10].

The American College of Obstetricians and Gynecologists (ACOG)recommendsusingwarmcompressesduringthesecond stageof laborduetoameta-analysisoffourstudiesthatfound significantlyreducedthird-degreeandfourth-degreelacerations [1].ArecentCochranereviewin2017reportednodifferencein termsofintactperineum,perinealtraumanotrequiringsuturing orrequiringsuturing,firstdegreeandseconddegreetears,buta significant reduction in the number of third and fourth-degree lacerations[22]. With theinclusion of threemore trials in our review we showed a shift occurring in the efficacy of warm compresses.

Conclusions

In conclusion, warm compressesapplied during the second stageoflaborincreasetheincidenceofintactperineumandlower

theriskofepisiotomyandsevereperinealtrauma.Moreresearchis neededintotheoptimaltemperatureofthewaterandlengthof time of application. Furtherresearchis needed todetermine if perinealwarmcompressesreduceurinaryincontinencefollowing thebirth.

Disclosure

Dahlenauthoredoneofthepapersincludedinthereview Financialsupport

Noﬁnancialsupportwasreceivedforthisstudy. Acknowledgments

We thank the authors of the original trials who provided additionalunpublisheddata.

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