Obstetrics I

Front 1

What composes the stages of normal labor?

Back 1

• First stage
• Second stage
• Third stage

Front 2

What are the components of the active phase of delivery (stage I)?

Back 2

Acceleration

Maximum Velocity

Deceleration

Front 3

When is the latent phase prolonged?

Back 3

• > 20 hours nulliparous
• > 14 hours multiparous

Front 4

What is the active phase average time?

Back 4

• 6.4 hours nulliparous
• 4.6 hours multiparous

Front 5

Second stage median time?

Back 5

• 50 minutes nulliparous
• 20 minutes multiparous

Front 6

What are protraction disorders?

Back 6

• Slower than normal progress
• e.g. prolonged 1st or 2nd stage

Front 7

What are arrest disorders?

Back 7

• Complete cessation of progress
  
• e.g. arrested 1st or 2nd stage

Front 8

What is the criteria for dystocia?

Back 8

• More than 4 hours of active labour with less than 0.5 cm/hr dilation
  
• More than 1 hour with no descent during active pushing

Front 9

Three main etiologies of abnormal labor

Back 9

• power
• passage
• passenger

Front 10

How to assess powers?

Back 10

Assess contraction pattern

• External: palpation, tocodynamometer
• Internal: intrauterine pressure catheter (IUPC)

Front 11

Ideally, what should contractions be?

Back 11

Contractions every 3 minutes lasting 60 seconds

(Montevideo units greater than 200 mmHG in 10 minutes)

Front 12

What factors affect power?

Back 12

• Maternal condition
  
• Drugs
  
• Parity
  
• Uterine size
  
• Advanced maternal age
  
• Obesity
  

Front 13

How to diagnose inadequate labour?

Back 13

In order to diagnose arrest during stage I

• latent phase has to be completed with cervix dilated 4 cm or more
• uterine contraction pattern of 200 Montevideo units or more in a 10 min period has been present for 2-4 hrs without cervical change

Front 14

How to treat abnormal powers?

Back 14

• Resuscitate mother
• Analgesia
• Positional change
• Amniotomy
• Oxytocin augmentation
• DO NOT use prostaglandins to augment labour

Front 15

How to resuscitate mother?

Back 15

• Dehydrate
  
• give calories and fluid
  
• Antibiotics
  

Front 16

What is induction?

Back 16

• Used to get a non labouring patient into labour
  
• Patient not contracting and cervix is closed
  

Front 17

What is augmentation?

Back 17

• Increasing the strength, duration, and frequency of contractions
  
• Cervix is effaced and dilated
  

Front 18

What drugs are available for induction?

Back 18

Prostaglandins (cervidil, prostin)

used when the cervix is not ripe;

can cause uterine hyperstimulation

Oxytocin: used to induce labour, especially if cervix is ripe

Foley catheter: can help ripen cervix

Front 19

When not to use prostaglandins?

Back 19

Never use in a labouring patient as may cause uterine hyperstimulation

CANNOT PREDICT OR CONTROL EFFECT ON THE UTERUS

Front 20

What is the goal of oxytocin?

Back 20

Produce sufficient uterine activity to effect progress without causing hyperstimulation

Front 21

Side effects of oxytocin?

Back 21

• Hyperstimulation
  
• Hypotension
  
• Fluid overload
  
• Uterine rupture
  

Front 22

What factors affect passage?

Back 22

Types of maternal pelvis

Soft tissue tumours

Front 23

How to estimate pelvic capacity?

Back 23

• Diagonal conjugate
  
• Interspinous diameter of midpelvis
  
• Intertuberous distances of pelvic outlet
  
• Narrow pelvis arch can signify narrow pelvis
  

Front 24

How can the passenger affect progress of labour?

Back 24

• presenting part
• size/fetal weight
• position of vertex (OP or OT)
• Attitude
• Fetal anomalies

Front 25

Risk factors of abnormal labour?

Back 25

• Older maternal age
• Pregnancy complications
• Non reassuring fetal heart rate
• Epidural anesthesia
• Macrosomia, twins
• Pelvic contraction
• Malpositions/malpresentations
• Short stature
• High station at fuull dilation
• Chorioamnionitis
• Postterm pregnancy
• Obesity
• Induction of labour

Front 26

Active management of labour, steps?

Back 26

• Diagnose labour by strict criteria: painful contractions with bloody show, rupture of membranes, or full cervical effacement
  
• Rupture intact membranes within one hour of diagnosis of labour
  
• Perform hourly cervical exams for first three hours of labour then at intervals no longer than every two hours
  
• Begin oxytocin if cervical dilation less than 1 cm/hr in first stage or failure of descent in second stage
  
• One-on-one nursing care throughout LDR