Fall_25_Abnormal_Presentation_Multiple_Gestation

Question 1

Define ‘presentation’ in obstetrics.

Answer 1

Part of the fetus overlying the pelvic inlet; the part that engages the birth canal. 【45†4】

Question 2

Which presentation is considered normal?

Answer 2

Cephalic presentation, subdivided into vertex, brow, and face by degree of neck flexion. 【45†4】

Question 3

Define ‘lie’ of the fetus.

Answer 3

Relationship between fetal and maternal spinal axes. Longitudinal lie is normal; transverse or oblique are abnormal. 【45†5】

Question 4

Define ‘position’ in fetal orientation.

Answer 4

Relation of a fetal bony point to maternal pelvis—occiput for vertex, sacrum for breech, mentum for face. 【45†6】

Question 5

What is ‘attitude’ of the fetus?

Answer 5

Relationship of fetal parts to each other; flexed, military, or hyperextended. 【45†6】

Question 6

Define ‘asynclitism.’

Answer 6

Fetal head tilted toward one shoulder; opposite parietal eminence enters first. 【45†4】

Question 7

List common abnormal presentations.

Answer 7

Breech, face, brow, compound, and shoulder (transverse lie). 【45†4】【45†19】【45†20】

Question 8

Define breech presentation.

Answer 8

Longitudinal lie where fetal buttocks/lower extremities present first. 【45†10】

Question 9

Three varieties of breech presentation?

Answer 9

Frank (hips flexed, knees extended), complete (hips/knees flexed), incomplete (one/both hips extended). 【45†10】

Question 10

Which breech type carries highest cord prolapse risk?

Answer 10

Incomplete breech, as the presenting part does not fill the cervix. 【45†12】

Question 11

Define face presentation.

Answer 11

Neck is hyperextended backward; occurs in ~1 in 600–800 births. 【45†19】

Question 12

Define brow presentation.

Answer 12

Cervical spine midway between flexion and extension; often requires cesarean for dystocia. 【45†19】

Question 13

Define compound presentation.

Answer 13

An extremity prolapses beside the main presenting part (often an upper extremity). 【45†20】

Question 14

Define shoulder presentation.

Answer 14

Also called transverse lie; mandates cesarean except after successful version or second twin extraction. 【45†20】

Question 15

Most common abnormal presentation?

Answer 15

Breech presentation. 【45†11】

Question 16

Success rate of external cephalic version (ECV)?

Answer 16

Approximately 58%. 【45†13】

Question 17

Optimal timing for ECV?

Answer 17

After 36–37 weeks, once fetus is mature but before engagement. 【45†13】

Question 18

Common contraindication to ECV?

Answer 18

Oligohydramnios. 【45†13】

Question 19

Key prerequisites for ECV success?

Answer 19

Unengaged presenting part, normal amniotic fluid, posterior fetal back, parous patient, non-obese mother. 【45†13】

Question 20

Pharmacologic adjunct to ECV?

Answer 20

Tocolytic (e.g., terbutaline) before manipulation; neuraxial analgesia improves success. 【45†14】

Question 21

Why monitor FHR and have OR ready during ECV?

Answer 21

Because fetal distress or cord compression may require emergent cesarean. 【45†14】

Question 22

Preferred mode of delivery for breech fetus?

Answer 22

Cesarean for most due to decreased expertise with vaginal breech delivery. 【45†15】

Question 23

When can planned vaginal breech delivery be reasonable?

Answer 23

Under strict hospital protocol with experienced team and informed consent. 【45†16】

Question 24

Three types of vaginal breech delivery?

Answer 24

Spontaneous, assisted (partial extraction), and total breech extraction. 【45†17】

Question 25

When is total breech extraction used?

Answer 25

Only for vaginal delivery of a second twin. 【45†17】

Question 26

Key anesthesia preparation for vaginal breech delivery?

Answer 26

Deliver in OR, antacid prophylaxis, readiness for GA, vigilance for cord compression. 【45†18】

Question 27

Define multiple gestation.

Answer 27

Simultaneous development of two or more fetuses in one uterus. 【45†3】

Question 28

Differentiate monozygotic vs dizygotic twins.

Answer 28

Monozygotic: one fertilized egg splits; dizygotic: two ova fertilized by different sperm. 【45†21】【45†22】【45†24】

Question 29

Incidence of monozygotic twins?

Answer 29

~4 per 1000 births. 【45†21】

Question 30

Incidence of dizygotic twins relative to monozygotic?

Answer 30

Two-thirds of twins are dizygotic. 【45†22】

Question 31

Can monozygotic twins differ genetically or phenotypically?

Answer 31

Yes; may not share equal genetic material or identical appearance. 【45†24】

Question 32

Chorionicity and amnionicity types?

Answer 32

Monochorionic-monoamniotic, monochorionic-diamniotic, dichorionic-diamniotic. 【45†27】

Question 33

Best time to determine chorionicity?

Answer 33

Ultrasound in first or early second trimester. 【45†27】

Question 34

Why is determining chorionicity important?

Answer 34

Predicts risk of vascular anastomoses (e.g., twin-to-twin transfusion). 【45†27】

Question 35

Cardiopulmonary change magnitude in twin gestation?

Answer 35

CO ↑20%, SV ↑15%, HR ↑3.5%, plus ↓FRC from uterine size. 【45†34】

Question 36

Plasma volume increase in twin pregnancy vs singleton?

Answer 36

An additional ~750 mL. 【45†34】

Question 37

How does multiple gestation affect maternal anemia risk?

Answer 37

Relative or actual anemia is common. 【45†34】

Question 38

Common maternal complications of multiple gestation?

Answer 38

↑ risk of preeclampsia, preterm labor, PPH, abruption, infection. 【45†36】

Question 39

How does fetal complication risk change in multiples?

Answer 39

↑ risk of twin-to-twin transfusion, cord prolapse, IUGR. 【45†35】

Question 40

Recommended delivery timing for twins and triplets?

Answer 40

Twins ~38 weeks, triplets ~35 weeks for lowest perinatal mortality. 【45†37】

Question 41

Best labor analgesia for multiple gestation?

Answer 41

Epidural—provides optimal analgesia and allows extension for emergent cesarean. 【45†38】

Question 42

Why establish large-bore IV before twin delivery?

Answer 42

Anticipate hemorrhage; ~500 mL more blood loss than singleton. 【45†36】【45†38】

Question 43

Where should twin deliveries occur?

Answer 43

In OR or setting ready for immediate cesarean conversion. 【45†38】

Question 44

Why is GA risk higher in multiple gestation?

Answer 44

↑O2 consumption and ↓FRC predispose to hypoxemia during apnea. 【45†39】

Question 45

Essential step before GA induction in multiple gestation?

Answer 45

Thorough denitrogenation and preoxygenation. 【45†39】

Question 46

During cesarean for twins, what prolongs incision-to-delivery interval?

Answer 46

Time to deliver multiple fetuses increases risk of neonatal acidemia. 【45†40】

Question 47

Who must be present during twin delivery?

Answer 47

Personnel skilled in neonatal resuscitation. 【45†40】

Question 48

Why replace epidural if block inadequate during twin labor?

Answer 48

Need reliable anesthesia for potential emergent cesarean; re-site catheter. 【45†38】

Question 49

Nonparticulate antacid rationale pre-labor?

Answer 49

Reduce aspiration pneumonitis risk during possible GA. 【45†18】

Question 50

Why may spinal be chosen for elective twin cesarean?

Answer 50

Provides rapid, dense block with predictable onset; safe if not urgent. 【45†39】

Question 51

Why may regional be preferred over GA?

Answer 51

Avoids airway risk, minimizes fetal exposure to volatile anesthetics. 【45†39】

Question 52

Key airway concern in multiple gestation GA?

Answer 52

Difficult ventilation/intubation due to decreased FRC, increased O2 use, airway edema. 【45†39】

Question 53

Primary maternal hemodynamic goal during twin delivery?

Answer 53

Maintain preload and prevent hypotension to preserve uteroplacental perfusion. 【45†38】【45†39】

Question 54

Uterine tone management intraop?

Answer 54

Uterotonics promptly after delivery to prevent atony from uterine overdistention. 【45†36】【45†39】

Question 55

Postpartum hemorrhage risk in twins vs singleton?

Answer 55

Approximately 500 mL greater average blood loss. 【45†36】

Question 56

Post-delivery monitoring priority in twin gestation?

Answer 56

Monitor for PPH, hypotension, respiratory compromise. 【45†36】【45†38】

Question 57

Key counseling before planned vaginal breech or twin delivery?

Answer 57

Discuss higher neonatal morbidity/mortality and need for skilled team. 【45†16】【45†40】

Question 58

Top obstetric causes of emergency cesarean in breech/twin?

Answer 58

Cord prolapse, fetal distress, failed version, arrest of labor. 【45†12】【45†35】

Question 59

Why are twin pregnancies at higher risk for preeclampsia?

Answer 59

Increased placental mass and antiangiogenic factors. 【45†36】

Question 60

Anesthetic management goal for TTTS surgery?

Answer 60

Optimize uteroplacental perfusion, avoid uterine hypertonus, maintain maternal oxygenation. 【45†27】【45†35】

Question 61

Summary principle of anesthesia in abnormal presentations and multiple gestation?

Answer 61

Be prepared for rapid conversion to cesarean; maintain maternal stability for fetal oxygenation. 【45†38】【45†40】