Labour Complications: Shoulder Dystocia, Placenta Previa, Abruption, Cord Prolapse

Labour Complications: Shoulder Dystocia, Placenta Previa, Abruption, Cord Prolapse

A high-density, practical guide for nurses, midwives, and medical professionals.

What Is This?

This guide covers four critical labour complications that demand rapid recognition and intervention to prevent maternal and fetal harm. You’ll learn how to identify, manage, and escalate these emergencies in real time.

Why it matters today: - Shoulder dystocia occurs in 0.2–3% of births, risking fetal asphyxia or brachial plexus injury. - Placenta previa complicates 1 in 200 pregnancies, causing life-threatening hemorrhage. - Placental abruption affects 1% of pregnancies but accounts for 10% of perinatal deaths. - Cord prolapse has a 50% fetal mortality rate if not managed within minutes.

Why It Matters

These complications are time-sensitive emergencies where delays increase morbidity and mortality. Mastering them: - Saves lives by enabling rapid, evidence-based responses. - Reduces litigation (e.g., shoulder dystocia is a top cause of obstetric malpractice claims). - Improves teamwork by clarifying roles in high-stress scenarios. - Optimizes outcomes with structured algorithms (e.g., HELPERR for shoulder dystocia).

Core Concepts

1. Shoulder Dystocia

Definition: Failure of the fetal shoulders to deliver after the head, due to impaction behind the pubic symphysis. Key facts: - Risk factors: Macrosomia (>4.5 kg), maternal diabetes, prolonged second stage, previous dystocia. - Warning signs: "Turtle sign" (head retracts against perineum), failure of restitution. - Complications: Fetal hypoxia, brachial plexus injury (Erb’s palsy), maternal postpartum hemorrhage (PPH).

2. Placenta Previa

Definition: Placental implantation over or near the cervical os, classified as: - Complete (covers os entirely). - Partial (partially covers os). - Marginal (edge reaches os). - Low-lying (within 2 cm of os). Key facts: - Risk factors: Prior C-section, multiparity, advanced maternal age, smoking. - Classic sign: Painless, bright-red vaginal bleeding in the 3rd trimester. - Complication: Massive hemorrhage (maternal exsanguination, fetal hypoxia).

3. Placental Abruption

Definition: Premature separation of the placenta from the uterine wall before delivery. Key facts: - Risk factors: Hypertension, trauma, cocaine use, polyhydramnios, rapid uterine decompression. - Classic triad: Vaginal bleeding + abdominal pain + uterine tenderness (may be concealed). - Complications: Maternal DIC, fetal hypoxia/death, uterine rupture.

4. Cord Prolapse

Definition: Umbilical cord descends through the cervix ahead of the fetal presenting part, causing compression. Key facts: - Risk factors: Malpresentation (breech, transverse lie), polyhydramnios, preterm labor, artificial rupture of membranes (AROM). - Warning sign: Sudden fetal bradycardia after membrane rupture. - Complication: Fetal hypoxia/death within 5–10 minutes if unrelieved.

How It Works: Management Algorithms

1. Shoulder Dystocia: HELPERR Mnemonic

Goal: Disimpact the shoulders while minimizing fetal injury. Steps:
1. Help – Call for backup (OB, anesthesia, neonatology).
2. Episiotomy – Not routinely recommended (only if soft-tissue obstruction).
3. Legs – McRoberts maneuver (hyperflex maternal hips to flatten sacrum).
4. Pressure – Suprapubic pressure (not fundal!) to dislodge anterior shoulder.
5. Enter – Internal maneuvers: - Rubin II (rotate posterior shoulder toward fetal chest). - Woods screw (rotate anterior shoulder 180°).
6. Remove posterior arm – Sweep arm across chest to reduce bisacromial diameter.
7. Roll – Gaskin maneuver (all-fours position) if other steps fail.

If all else fails: Zavanelli maneuver (push head back in for C-section) or symphysiotomy (last resort).

2. Placenta Previa: Stabilize & Deliver

Goal: Prevent hemorrhage while ensuring fetal oxygenation. Steps:
1. Assess: Confirm diagnosis via transvaginal ultrasound (avoid digital exam!).
2. Stabilize: - IV access (2 large-bore cannulas). - Type & crossmatch (4+ units PRBCs). - Fetal monitoring (continuous CTG).
3. Deliver: - Complete previa-Emergent C-section (even if preterm). - Marginal/low-lying-Trial of labor if >2 cm from os, but C-section if bleeding persists.
4. Postpartum: - Oxytocin to prevent PPH. - Uterine artery embolization if bleeding continues.

3. Placental Abruption: Deliver or Stabilize?

Goal: Balance maternal stability with fetal viability. Steps:
1. Assess severity: - Mild (no distress, <1/3 separation)-Expectant management (steroids if preterm). - Moderate/severe (fetal distress, >1/3 separation)-Emergent delivery.
2. Stabilize: - IV fluids (crystalloid bolus). - Blood products (PRBCs, FFP, platelets if DIC). - Foley catheter (monitor urine output).
3. Deliver: - Vaginal delivery if stable and fetal heart rate (FHR) reassuring. - C-section if: - Fetal distress. - Maternal instability. - Failed induction.

4. Cord Prolapse: Relieve Compression Immediately

Goal: Restore umbilical blood flow within 5 minutes. Steps:
1. Call for help (OB, anesthesia, neonatology).
2. Relieve pressure: - Manual elevation (gloved hand pushes presenting part off cord). - Knee-chest position (gravity reduces compression). - Fill bladder (500 mL saline via Foley to lift presenting part).
3. Prepare for delivery: - Emergent C-section (unless vaginal delivery imminent). - Tocolytics (terbutaline) if contractions worsen compression.

Hands-On: Simulated Scenarios

Prerequisites

• Knowledge: Basic obstetric anatomy, fetal monitoring (CTG interpretation).
• Equipment: Birthing mannequin, fetal monitor, IV supplies, emergency drugs (oxytocin, terbutaline).
• Team: OB, midwife, anesthetist, neonatologist.

Scenario 1: Shoulder Dystocia (HELPERR in Action)

Steps:
1. Recognize: Head delivers but retracts ("turtle sign").
2. Call for help (shout for OB and anesthesia).
3. McRoberts maneuver (hyperflex hips, apply suprapubic pressure).
4. Internal rotation (Rubin II or Woods screw).
5. Deliver posterior arm if needed.
6. Document: Time of dystocia, maneuvers used, fetal outcome.

Expected outcome: Shoulders deliver within 2–3 minutes; fetal heart rate recovers.

Scenario 2: Cord Prolapse (5-Minute Drill)

Steps:
1. Recognize: Sudden fetal bradycardia after AROM.
2. Check for cord: Sterile vaginal exam reveals pulsating cord.
3. Relieve pressure: - Push presenting part upward with gloved hand. - Place patient in knee-chest position.
4. Prepare for C-section: - Notify OR team. - Administer terbutaline 0.25 mg SC to stop contractions.
5. Deliver within 5 minutes.

Expected outcome: Fetal heart rate normalizes; neonate delivered with Apgars ?7.

Common Pitfalls & Mistakes

Best Practices

Shoulder Dystocia

• Time maneuvers: Document start/end times (goal: <5 minutes).
• Avoid traction: Never pull on the fetal head (risk of brachial plexus injury).
• Team debrief: Review case to improve future responses.

Placenta Previa

• Antenatal diagnosis: Identify via 20-week anatomy scan.
• Avoid intercourse/digital exams if previa suspected.
• Plan delivery: Schedule C-section at 36–37 weeks if complete previa.

Placental Abruption

• Suspect in trauma: Even minor falls can cause abruption.
• Monitor for DIC: Check fibrinogen, platelets, PT/PTT.
• Deliver if unstable: Don’t wait for fetal maturity if mother is bleeding.

Cord Prolapse

• Prevent iatrogenic prolapse: Avoid AROM if presenting part is high.
• Keep hand in vagina until C-section begins (maintains pressure relief).
• Assign a "cord holder" to keep presenting part elevated during transfer.

Tools & Frameworks

Real-World Use Cases

1. Shoulder Dystocia in a Diabetic Mother

Scenario: A 34-year-old G2P1 with gestational diabetes delivers a 4.8 kg infant. The head delivers but retracts. Action: - Apply McRoberts + suprapubic pressure (successful). - Document maneuvers and fetal outcome (no Erb’s palsy). Outcome: Neonate delivered with Apgars 8/9.

2. Placenta Previa with Massive Hemorrhage

Scenario: A 38-year-old G4P3 at 32 weeks presents with painless bleeding (500 mL). Ultrasound confirms complete previa. Action: - Emergent C-section (general anesthesia due to bleeding). - Transfuse 4 units PRBCs + 2 units FFP. Outcome: Mother stable; neonate admitted to NICU for prematurity.

3. Cord Prolapse in a Breech Presentation

Scenario: A 28-year-old G1P0 at 36 weeks has sudden fetal bradycardia after AROM. Exam reveals cord prolapse. Action: - Manual elevation + knee-chest position. - Emergent C-section (delivery in 6 minutes). Outcome: Neonate resuscitated; Apgars 5/7.

Check Your Understanding (MCQs)

Question 1

A 25-year-old G1P0 at 39 weeks delivers the fetal head, but it retracts against the perineum. What is the first maneuver you should attempt? A. Apply fundal pressure. B. Perform an episiotomy. C. Hyperflex the maternal hips (McRoberts maneuver). D. Attempt internal rotation immediately.

Correct Answer: C (McRoberts maneuver). Explanation: McRoberts is the first-line intervention for shoulder dystocia, with a 90% success rate. Fundal pressure (A) risks brachial plexus injury. Episiotomy (B) is only for soft-tissue obstruction. Internal rotation (D) is a later step. Why the Distractors Are Tempting: - A: Fundal pressure is a common but dangerous mistake. - B: Episiotomies are overused; they don’t resolve bony obstruction. - D: Internal maneuvers are reserved for after McRoberts fails.

Question 2

A 30-year-old G2P1 at 34 weeks presents with painless, bright-red vaginal bleeding (300 mL). Ultrasound shows the placenta covering the cervical os. What is the next best step? A. Perform a digital exam to assess cervical dilation. B. Administer oxytocin to induce labor. C. Prepare for emergent C-section. D. Admit for observation and repeat ultrasound in 48 hours.

Correct Answer: C (Prepare for emergent C-section). Explanation: Complete placenta previa requires immediate C-section to prevent catastrophic hemorrhage. Digital exam (A) can trigger bleeding. Oxytocin (B) is contraindicated. Observation (D) is unsafe. Why the Distractors Are Tempting: - A: Digital exams are contraindicated in previa (risk of hemorrhage). - B: Induction is not an option with complete previa. - D: Delaying delivery risks maternal/fetal death.

Question 3

A 22-year-old G1P0 at 38 weeks has sudden fetal bradycardia (80 bpm) after artificial rupture of membranes. On exam, you feel a pulsating cord in the vagina. What is the priority action? A. Administer terbutaline to stop contractions. B. Push the presenting part upward with a gloved hand. C. Prepare for immediate vaginal delivery. D. Place the patient in Trendelenburg position.

Correct Answer: B (Push the presenting part upward). Explanation: Manual elevation relieves cord compression immediately, buying time for C-section. Terbutaline (A) is secondary. Vaginal delivery (C) is rarely possible. Trendelenburg (D) is less effective than knee-chest. Why the Distractors Are Tempting: - A: Terbutaline is useful but not the first step. - C: Vaginal delivery is too slow in most cases. - D: Trendelenburg is less effective than knee-chest.

Learning Path

Further Resources

Books

• Obstetric and Intrapartum Emergencies (Sabaratnam Arulkumaran) – Practical algorithms.
• Queenan’s Management of High-Risk Pregnancy – Evidence-based protocols.

Courses

• ALSO (Advanced Life Support in Obstetrics) – Hands-on training for emergencies.
• PROMPT (Practical Obstetric Multi-Professional Training) – Team-based