Christopher R. Graber, MDSalina Women’s Clinic

7 May 2010

OverviewBackgroundNormal Labor

Friedman curveAbnormal Labor (dystocia)

Risk factors for dystociaComplications from dystocia

AugmentationOther

BackgroundLabor – uterine contractions of sufficient

intensity, frequency, and duration to cause cervical effacement and dilationA retrospective diagnosisLatent vs. active

Dystocia – slow, abnormal progression of laborLeading indication for C/SResponsible for 60% of all C/S

Normal LaborContractions dilation deliveryFirst stage – dilation up to 10cm

Latent activeSecond stage – from 10cm to deliveryThird stage – del baby to del placentaFourth stage – until 6w postpartumFriedman curve

Developed in 1950’s, challenged recently

Normal LaborFirst Stage (minimum; Friedman)

Nulliparas – 1.2 cm dilation/hrMultiparas – 1.5 cm dilation/hr

First Stage (Alexander, 2002)Epidural slows active phase by 1hr

Second Stage (median; Kilpatrick, 1989)Nulliparas – 50 minMultiparas – 20 min

Abnormal LaborAnything not normalPower, passenger, passage

CPD, failure to progress, dystociaArrest of dilation vs. Arrest of descent

Protraction Second stage arrest/prolongation

Nullip – 2h (3h w/ epidural)Multip – 1h (2h w/ epidural)

Risks for DystociaMaternal ageMedical complications of pregnancy

Diabetes, hypertension, PROMChorio, macrosomia, pelvic contractions

Second stageNulliparity, epidural analgesia, OP, long first

stage

Complications from DystociaChorioamnionitisFetal infection and bacteremiaPelvic floor injuries?

Pressure necrosis fistula formationIncreased risk of operative delivery

AugmentationConsider oxytocin for protraction or arrestGoal: 3-5 ctx in 10min, >200 Montevideo

units“2-hour rule” should likely be 4-6 hours

If second stage arrestContinued observation (continued

augmentation)Operative vaginal deliveryCesarean delivery

Low-dose vs. high-dose oxytocin

OtherNo clear role for pelvimetry in prediction of

dystociaWalking during labor doesn’t hurt or helpContinuous support during labor is

encouragedAmniotomy may enhance progress of active

labor but increases risk of feverWomen with twins may have augmentation

Induction and Augmentation(by me)Bishop score to determine if cervical ripening

is neededCervidil (dinoprostone) vs cytotec (misoprostol)

Pitocin – start at 2mu/minIncrease by 2mu every 15 minutesMaximum 40mu/min

TipsIf reach 40 and no Δ, off for 30 min then

restart 20Consider (re-)prostaglandin

ReferencesACOG practice bulletin 49

Dystocia and Augmentation of LaborACOG practice bulletin 10

Induction of Labor