Intrapartum Care and Abnormal Labor

Intrapartum Care Intrapartum Care & Abnormal Labor& Abnormal Labor

Francis S. Nuthalapaty, MD

Medical Student Lecture SeriesDepartment of Obstetrics & GynecologyDepartment of Obstetrics & GynecologyGreenville Hospital System University Greenville Hospital System University Medical CenterMedical CenterGreenville, South CarolinaGreenville, South Carolina

Learning ObjectivesLearning ObjectivesAPGO ET-11: Intrapartum Care

Understanding the process of normal labor and delivery allows optimal

care and reassurance for the parturient and timely recognition of

abnormal events.

APGO Medical Student Educational Objectives 8th Ed. 2004

Learning Objectives Learning Objectives ET-11ET-11

Objective Level of Competence

List the signs and symptoms of labor KH

Describe the three stages of labor and recognize common abnormalities

KH

Describe the steps of a vaginal delivery SH

Describe the different methods of delivery with the indications and contraindications of each

KH

Describe the evaluation of common puerperal complications

KH


Learning ObjectivesLearning ObjectivesAPGO Educational Topic 22:

Abnormal LaborLabor is expected to progress in an

orderly and predictable manner. Careful observation of the mother and fetus during labor will allow

early detection of abnormalities so that management can be directed to

optimize outcome.APGO Medical Student Educational Objectives 8th Ed. 2004

Learning Objectives ET-Learning Objectives ET-2222

ObjectiveLevel of

Competence

List abnormal labor patterns K

Describe methods of fetal surveillance K

Discuss fetal and maternal complications of abnormal labor

K

List indications and contraindications for oxytocin administration

K


Learning Objectives ET-Learning Objectives ET-2222

ObjectiveLevel of

Competence

List indications for VBAC K

Discuss strategies for emergency management of breech, shoulder dystocia and cord prolapse

K


TerminologyTerminology• Gravidity

–#of current and completed pregnancies of any kind

• Parity–# of completed pregnancies ≥ 20 weeks

–not delivered infants (e.g. twins)

TerminologyTerminology

•Nullipara

•Primipara

•Multipara

•Grand Multipara


• TPAL Nomenclature:T = Term deliveries ≥ 37 wksP = Preterm deliveries < 37 wksA = Abortions (< 20 wks)L = Living children

• G3/P1-0-1-1:


• G3/P1-0-1-1:

–3rd Pregnancy

–1 Term delivery

–0 Preterm deliveries

–1 Abortion

–1 Living child


• G5/P2-1-1-0:


• G5/P2-1-1-0:

–5th Pregnancy

–2 Term deliveries

–1 Preterm delivery

–1 Abortion

–0 Living children


• G2/P0-2-0-3:


• G2/P0203:

–2nd Pregnancy

–0 Term deliveries

–2 Preterm deliveries

–0 Abortions

–3 Living children


•Fetal Presentation•Attitude•Fetal Lie•Fetal Position•Fetal Station


Designates the fetal part over the pelvic inlet

Fetal PresentationFetal Presentation

Presentation % Incidence

Cephalic 96.8---Breech 2.7 1:36Transverse 0.3 1:335Compound 0.1 1:1000Face 0.051:2000Brow 0.011:10,000

Williams Obstetrics, 21st Ed. 452.

Fetal PresentationFetal Presentation

Cephalic Presenting Cephalic Presenting DiametersDiameters

FACE

SINCIPUTMILITARY

BROW VERTEXFLEXED

Figure 9-2 Lateral view of the fetal skull showing the prominent landmarks and the anteroposterior diameters.

The degree of flexion a fetus assumes during labor or the relation of the fetal parts to

each other

Fetal AttitudeFetal Attitude

Variations in Fetal Variations in Fetal AttitudeAttitude

SINCIPUT, MILITARY BROW FACEVERTEX, FLEXED

Fetal LieFetal Lie•Refers to the relation of the long axis of

fetus (back) to the long axis of the mother:

------ Transverse ------ -------------- Longitudinal ----------------

Diagnosis of Fetal Diagnosis of Fetal PresentationPresentation

•Abdominal Palpation– - Leopold’s Maneuvers

Diagnosis of Fetal Diagnosis of Fetal PresentationPresentation

•Abdominal Palpation– - Leopold’s Maneuvers

•Vaginal Examination•Auscultation•Sonography

Fetal PositionFetal PositionRefers to the relation of an

arbitrarily chosen portion of the fetal presenting part to the right or left side of the maternal birth

canal

• Reference points (denominators) are:

Fetal occiput

Fetal chin (mentum)

Fetal sacrum

Fetal Head: Fetal Head: LandmarksLandmarks

Figure 9-1 Superior view of the fetal skull showing the sutures, fontanelles, and transverse diameters.

Occiput PresentationOcciput Presentation

Fetal Position Fetal Position

OP

LOT

OA

ROT

LOPROP

LOAROA

•LOT: 40%•ROT: 20%•OP: 20%


?????


Left OcciputAnterior


?????


Right Occiput

Posterior


?????


Left OcciputTransver

se

The relationship of the fetal presenting part to the level

of the ischial spines

Fetal StationFetal Station

Fetal StationFetal Station

World Health Organization: Managing Complications in Pregnancy and Childbirth World Health Organization: Managing Complications in Pregnancy and Childbirth www.who.int/reproductivehealth/impac/Clinical_Principles/Normal_labour_C57_C76.htmlwww.who.int/reproductivehealth/impac/Clinical_Principles/Normal_labour_C57_C76.html

Clinical CorrelationClinical Correlation

• Correct identification of fetal position relative to the birth canal is critical!

• Document the following:– Fetal Lie – Fetal Presentation – Fetal Position– Fetal Station

LaborLabor

TerminologyTerminology• False Labor (Braxton-Hicks ctx)

– May be present from first trimester

– Irregular, nonrhythmic

• True Labor

– Rhythmic contractions with cervical

change

Essential Factors of LaborEssential Factors of Labor(The 3 P’s)(The 3 P’s)

• Passage

• Powers

• Passenger

The 3 P’s of LaborThe 3 P’s of LaborPassagePassage

PassagePassage

•Bony Pelvis–inlet

–midpelvis

–outlet

•Soft Tissue

Caldwell-Moloy Caldwell-Moloy ClassificationClassification

A

P

Gynecoid

A

P

Android

P

A

Platypelloid

P

A

Anthropoid

Caldwell-Moloy ClassificationCaldwell-Moloy Classification

• Gynecoid = 40 – 50% (10-15% AA)

• Android = 30%

• Anthropoid = 20% (40% in AA)

• Platypelloid = 2- 5%

Gynecoid PelvisGynecoid Pelvis• Round at the inlet, with the widest

transverse diameter only slightly greater than the anteroposterior diameter

• Side walls straight• Ischial spines of average prominence• Well-rounded sacrosciatic notch• Well-curved sacrum• Spacious subpubic arch, with an angle

of approximately 90 degrees

Android PelvisAndroid Pelvis• Triangular inlet with a flat

posterior segment and the widest transverse diameter closer to the sacrum than in the gynecoid type

• Convergent side walls with prominent spines

• Shallow sacral curve• Long and narrow sacrosciatic notch• Narrow subpubic arch

Anthropoid PelvisAnthropoid Pelvis• A much larger AP than transverse

diameter, creating a long narrow oval at the inlet

• Side walls that do not converge• Ischial spines that are not prominent but

are close, owing to the overall shape• Variable, but usually posterior,

inclination of the sacrum• Large sacrosciatic notch• Narrow, outwardly shaped subpubic arch

Pelvic Landmarks - Pelvic Landmarks - InletInlet

•Sacral promontory

•Illiopectineal line

•Symphysis pubis

mywebpages.comcast.net/wnor/pelvis.htm --Wesley Norman, PhD, DSc Georgetown University


http://images.google.com/url?q=http://mywebpages.comcast.net/wnor/pelvis.htm&usg=AFrqEzeKG5wtFoZF1JuK_xpTqdCUyl2DUQ


Vaginal Examination to Vaginal Examination to Determine the Diagonal Determine the Diagonal

ConjugateConjugate

Pelvic Landmarks - Pelvic Landmarks - MidMid

•Ischial spines

•Sacrum

•Sacrosciatic notch

mywebpages.comcast.net/wnor/pelvis.htm --Wesley Norman, PhD, DSc Georgetown University

Pelvic Landmarks - Pelvic Landmarks - MidMid

http://images.google.com/url?q=http://mywebpages.comcast.net/wnor/pelvis.htm&usg=AFrqEzeKG5wtFoZF1JuK_xpTqdCUyl2DUQ

Assessment of Mid-Assessment of Mid-pelvispelvis

Pelvic Landmarks - Pelvic Landmarks - OutletOutlet

•Pubic arch

•Ischial tuberosities

•Sacrococcygeal joint

Pelvic Landmarks - Pelvic Landmarks - OutletOutlet

Figure 9-4 Pelvic outlet and its diameters.

Assessment of Pelvic Assessment of Pelvic OutletOutlet

Minimum PelvimetricsMinimum PelvimetricsPelvic

Plane DiameterLength

(cm)

Inlet Diagonal conjugate

11.5

Midplane Bispinous 10.5*

Outlet Bituberous 8* Average measurement, no minimum defined

The 3 P’s of LaborThe 3 P’s of LaborPowersPowers

PowersPowers

•50 mm Hg or more

•Contractions occur q 2-3

minutes

•Upper uterus more active with

pacemakers at cornual

The 3 P’s of LaborThe 3 P’s of LaborPassengerPassenger

PassengerPassenger• Head is typically the largest

structure

• Molding

• Smallest diameter of head:– suboccipitobregmatic

• Abnormal lie or size or presentation can cause problems

Passenger: Fetal Head Passenger: Fetal Head ConsiderationsConsiderations

• Bones in face fused but cranial vault has movable bones

• Molding is when bones overlap under pressure

• Sutures are membranous spaces between bones

• Fontanelles or “soft spots” are the intersections between sutures

MoldingMolding

Relationship between the passage and the fetus

Engagement Station Fetal position

Passage and Passenger Passage and Passenger RelationshipRelationship

• Engagement –the fetal head is thru the pelvic inlet when fetal BPD reaches the ischial spines

Relationship between the passage and the fetus

Engagement Station Fetal position

Passage and Passenger Passage and Passenger RelationshipRelationship

• Station - descent of the fetal BPD, relative to the level of the ischial spines.

COURSE OF NORMAL COURSE OF NORMAL LABORLABOR

Labor DefinitionLabor Definition

The physiologic process by which the gravid uterus evacuates its contents at or near term by a mechanism involving coordinated sequence of periodic contractions of the myometrium effecting progressive cervical dilatation and fetal descent through the birth canal.

- Emanuel A. Friedmin

First Stage of LaborFirst Stage of Labor• Onset of true labor until cervix

fully dilated:

Latent Phase Active Phase

First Stage of LaborFirst Stage of Labor

First Stage of LaborFirst Stage of Labor

Second Stage of LaborSecond Stage of Labor

• Complete dilatation to delivery of the infant

Cardinal Movements Cardinal Movements of Laborof Labor

• Engagement, descent, flexion

• Internal rotation

• Complete rotation with beginning of extension

• Complete extension

• External Rotation (Restitution)

• External rotation with delivery of Anterior shoulder

• Expulsion with delivery of Posterior shoulder

Third Stage of LaborThird Stage of Labor

• Delivery of the infant to delivery of the placenta

Third Stage of LaborThird Stage of Labor• Placental separation:

– Uterus becomes firmer

– Gush of blood– Uterus rises in

abdomen as placenta passes into lower segment

– Lengthening of umbilical cord

Stages: cont’d

Third stage Placental separation Placental delivery

Fourth stage 1-4 hours

Power: Forces of Power: Forces of LaborLabor

• First Stage of Labor– Primary Forces = Uterine ctx to dilate cervix

to 10 cm

• Second Stage of Labor– Secondary Forces = Abdominal muscles to

push fetus out after cervix is fully dilated

• Third Stage of Labor- Primary Forces = Uterine ctx to deliver

placenta

INTRAPARTUM INTRAPARTUM MANAGEMENTMANAGEMENT

Fetal Heart Rate Fetal Heart Rate MonitoringMonitoring

• External:

Indirect - Doppler ultrasound

• Internal:

Direct – Scalp electrode


• External:

– Assessment of:

• baseline, variability, accelerations,

decelerations

– Limitations:

• Maternal Body Habitus

• Maternal/Fetal Movement Artifact


• Internal:– Assessment of:

• baseline, variability, accelerations, decelerations

– Limitations:

• Membranes must be ruptured

• Minimally invasive

• Increase risks of Hep B/HIV if mother +

• Maternal HR detected if FHR absent

Contraction Contraction MonitoringMonitoring

• External:

– Indirect: Abdominal pressure

electrode

• Internal:

– Direct: IUPC with pressure sensor


• External:

- Can detect presence and interval of ctx,

but not strength

- Limitations:

Maternal Body Habitus

Maternal/Fetal Movement Artifact

Factitious contractions


• Internal:

- Assessment of BOTH frequency

and

intensity of contractions

- Limitations:

Membranes must be ruptured

Minimally invasive

Intrapartum MonitorsIntrapartum Monitors

Fetal Heart Rate Fetal Heart Rate InterpretationInterpretationAssessmentAssessment

• Quality of tracing

• Baseline fetal heart rate

• Describe overall variability

• Presence of accelerations?

• Presence of decelerations?

• Contraction frequency/intensity

Fetal Heart Rate TracingFetal Heart Rate Tracing

Fetal Monitoring Fetal Monitoring GuidelinesGuidelines

Normal Labor Normal Labor ParametersParameters

Source: Modified from Friedman EA. Labor: Clinical Evaluation and Management, 2nd ed. New York. Appletion-Century-Cronz 1370.43

Nulliparous Labor

MeanLower Limit

(95%)

Latent 8.6 h 20.6 h

Active 4.9 h 11.5 h

Deceleration 54 min 3.3 h

Maximum Slope 3.0 cm/h 1.2 cm/h

Second Stage 57 min 2.5 h

Normal Labor Normal Labor ParametersParameters

Source: Modified from Friedman EA. Labor: Clinical Evaluation and Management, 2nd ed. New York. Appletion-Century-Cronz 1370.43

Multiparous Labor

MeanLower Limit

(95%)

Latent 5.3 h 13.6 h

Active 2.2 h 5.2 h

Deceleration 14 min 53 min

Maximum Slope 5.7 cm / h 1.5 cm/h

Second Stage 14 min 50 min

Abnormal Labor Abnormal Labor Assessment Assessment Clinical Caveat

Labor dystocia requires a close assessment of the 3-P’s to determine the etiology and

implement appropriate management changes to address

the problem identified.

Adequate LaborAdequate Labor• Defined as > 200 Montevideo

units (MVU) as measured by IUPC

• MVU = Sum of contraction strength for each contraction occurring over 10 minutes

MVUs = ????MVUs = ????

MVUs = 270MVUs = 270“Adequate Labor”“Adequate Labor”

7 Labor Dysfunctions7 Labor Dysfunctions1. Prolonged Latent Phase

– Definition:• > 20 hours nullipara• > 14 hours multipara

– Treatment:• “Therapeutic rest” = sedatives

– 85% awaken in 6-10 hours and progress to active phase

– 10% have stopped contracting– 5% continue to contract without progression,

requiring uterine stimulation.

• Oxytocin

7 Labor Dysfunctions7 Labor Dysfunctions2. Protracted Active Phase

– Definition:• Cervical dilation < 1.2 cm/h nullipara• Cervical dilation < 1.4 cm/h multipara

– Treatment:• Evaluate passenger, passageway, power• IUPC to calculate MVU (goal > 200)• Oxytocin augmentation

7 Labor Dysfunctions7 Labor Dysfunctions3. Protracted Deceleration Phase

– Definition:• > 3 hours nullipara• > 1 hour multipara

– Treatment:• Same as for protracted active phase• Evaluate passenger, passageway, power• IUPC to calculate MVU (goal > 200)• Oxytocin augmentation

7 Labor Dysfunctions7 Labor Dysfunctions4. Secondary Arrest of Dilatation

in Active phase– Definition:

• Absence of cervical change over 2 hours*• MVU > 200

– Treatment:• Cesarean delivery

* Extension to 4 hours results in higher rate of vaginal delivery (92%) and is also acceptable

7 Labor Dysfunctions7 Labor Dysfunctions5. Protracted Descent

– Definition:• < 1 cm/h nullipara• < 2 cm/h multipara


7 Labor Dysfunctions7 Labor Dysfunctions7. Arrest of Descent in Second

Stage– Definition:

• No descent of presenting part in:• > 2 hours (or > 3 hours with CLE) nullipara• > 1 hour (or > 2 hours with CLE) multipara

– Treatment:• Continued observation• Operative vaginal delivery• Cesarean delivery

7 Labor Dysfunctions7 Labor Dysfunctions6. Failure of Descent

– Definition:• No descent in > 1 hour nullipara• No descent in > 30 min multipara


Labor Assessment Labor Assessment Case 1Case 1

• 32 yo G1P0 36 weeks presented with contractions. Looks uncomfortable, and is contracting every 3 minutes but cervix is 2 cm and 50% effaced. Was seen the previous day with similar complaints and findings.

• Diagnosis:

• Management:


• 32 yo G1P0 36 weeks presented with contractions. Looks uncomfortable, and is contracting every 3 minutes but cervix is 2 cm and 50% effaced. Was seen the previous day with similar complaints and findings.

• Diagnosis:– Prolonged latent phase

• Management:– “Therapeutic Rest”


• 24 yo P1001 39 weeks presented in labor. Contracting every 3 minutes but looks comfortable. Progressed from 4 to 6 centimeters in 6 hours. Membranes intact. Estimated fetal weight – 3000 grams. Pelvis adequate on examination. Vertex presentation.

• Diagnosis:

• Management:


• 24 yo P1001 39 weeks presented in labor. Contracting every 3 minutes but looks comfortable. Progressed from 4 to 6 centimeters in 6 hours. Membranes intact. Estimated fetal weight – 3000 grams. Pelvis adequate on examination. Vertex presentation.

• Diagnosis:– Protracted active phase likely secondary to

inadequate labor (insufficient power)• Management:

– Amniotomy, Oxytocin augmentation +/- IUPC


• 32 yo P0000 Class C diabetic at 40 weeks undergoing labor induction. Contracting every 2-3 minutes. 7 cm dilation x 4 hours. Confirmed adequate labor with intrauterine pressure catheter. Membranes ruptured, Estimated fetal weight – 4200 grams. Pelvis adequate on examination. Vertex presentation.

• Diagnosis:

• Management:


• 32 yo P0000 Class C diabetic at 40 weeks undergoing labor induction. Contracting every 2-3 minutes. 7 cm dilation x 4 hours. Confirmed adequate labor with intrauterine pressure catheter. Membranes ruptured, Estimated fetal weight – 4200 grams. Pelvis adequate on examination. Vertex presentation.

• Diagnosis:– Arrest of dilatation likely secondary to cephalopelvic

disproportion/fetal macrosomia (Passenger too big for pelvis)

• Management: Cesarean Delivery


• 28 yo P0101 at 42 weeks presented in labor. History of previous MVA with pelvic fracture. Contracting every 2-3 minutes. 6 cm dilation x 4 hours. Confirmed adequate labor with intrauterine pressure catheter. Membranes ruptured, Estimated fetal weight – 3200 grams. Constricted pelvic inlet with non-engaged fetal head. Vertex presentation.

• Diagnosis:

• Management:


• 28 yo P0101 at 42 weeks presented in labor. History of previous MVA with pelvic fracture. Contracting every 2-3 minutes. 6 cm dilation x 4 hours. Confirmed adequate labor with intrauterine pressure catheter. Membranes ruptured, Estimated fetal weight – 3200 grams. Constricted pelvic inlet with non-engaged fetal head. Vertex presentation.

• Diagnosis: – Arrest of dilatation likely secondary to cephalopelvic

disproportion/abnormal pelvis (Pelvis too small for pelvis)

• Management: Cesarean Delivery

Health & Medicine

Intrapartum Care and Abnormal Labor