Obstetric Emergencies

Introduction

Obstetric emergencies are critical situations that can occur during pregnancy, labor, or the postpartum period. These emergencies require prompt recognition, effective management, and coordination among healthcare providers. This guide aims to provide an overview of common obstetric emergencies encountered in clinical practice, along with key concepts to remember for the USMLE examination.

Table of Contents

1. Antepartum Emergencies
   • Placental Abruption
   • Ectopic Pregnancy
   • Preterm Labor
2. Intrapartum Emergencies
   • Shoulder Dystocia
   • Uterine Rupture
   • Amniotic Fluid Embolism
3. Postpartum Emergencies
   • Postpartum Hemorrhage
   • Postpartum Infection
   • Postpartum Preeclampsia

Antepartum Emergencies

Placental Abruption

• Definition: Premature separation of the placenta from the uterine wall.
• Clinical Features: Sudden-onset vaginal bleeding, severe abdominal pain, uterine tenderness, fetal distress.
• Management: Immediate resuscitation, blood transfusion if necessary, delivery if maternal-fetal status deteriorates.

Ectopic Pregnancy

• Definition: Implantation of a fertilized ovum outside the uterine cavity.
• Clinical Features: Lower abdominal pain, vaginal bleeding, amenorrhea, adnexal tenderness/mass.
• Management: Methotrexate therapy (if stable and early), surgical intervention (if unstable or late).

Preterm Labor

• Definition: Labor occurring before 37 weeks of gestation.
• Clinical Features: Uterine contractions, cervical dilation, lower back pain, vaginal discharge.
• Management: Tocolysis (e.g., beta-agonists, calcium channel blockers), corticosteroids for fetal lung maturation, magnesium sulfate for neuroprotection.

Intrapartum Emergencies

Shoulder Dystocia

• Definition: Difficulty delivering the fetal shoulders after delivery of the head.
• Clinical Features: Head-to-body delivery time >60 seconds, inability to deliver the shoulders with gentle downward traction.
• Management: McRoberts maneuver, suprapubic pressure, rotational maneuvers, episiotomy, Zavanelli maneuver (last resort).

Uterine Rupture

• Definition: Complete or partial separation of the uterine wall, often at a previous cesarean delivery scar site.
• Clinical Features: Sudden-onset abdominal pain, vaginal bleeding, fetal bradycardia, loss of fetal station.
• Management: Immediate surgical exploration (laparotomy), blood transfusion, delivery if maternal-fetal status deteriorates.

Amniotic Fluid Embolism

• Definition: Rare, life-threatening condition characterized by the entry of amniotic fluid into the maternal circulation.
• Clinical Features: Sudden-onset dyspnea, hypotension, cyanosis, fetal distress.
• Management: Supportive care, immediate delivery if fetal status permits, cardiopulmonary resuscitation if necessary.

Postpartum Emergencies

Postpartum Hemorrhage

• Definition: Blood loss >500 mL within 24 hours after vaginal delivery or >1000 mL after cesarean delivery.
• Clinical Features: Excessive or prolonged vaginal bleeding, hypotension, tachycardia.
• Management: Uterine massage, uterotonic medications (e.g., oxytocin, misoprostol), fluid resuscitation, surgical interventions (e.g., uterine artery ligation, hysterectomy).

Postpartum Infection

• Definition: Infection occurring within 6 weeks after delivery.
• Clinical Features: Fever, uterine tenderness, foul-smelling lochia, abdominal pain.
• Management: Broad-spectrum antibiotics, uterine drainage if necessary, supportive care.

Postpartum Preeclampsia

• Definition: New-onset or worsening hypertension with end-organ dysfunction after delivery.
• Clinical Features: Hypertension, proteinuria, headaches, visual changes, edema.
• Management: Antihypertensive therapy, magnesium sulfate for seizure prophylaxis, close monitoring of end-organ function.

Remember to review each condition in detail, including risk factors, pathophysiology, diagnosis, and management, to ensure comprehensive preparation for the USMLE examination.