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COH – MIDWIFERY SYNOPSIS 4

MIDWIFERY MEDICINES, SURGERIES.

Uterotonics (Drugs That Stimulate Uterine Contractions)

Definition:
Uterotonics are medications that stimulate uterine contractions to induce labour, prevent postpartum hemorrhage (PPH), or aid in incomplete abortions.

Common Uterotonics & Their Uses:

DrugMechanism of ActionIndicationsDosage & RouteContraindications
Oxytocin (Pitocin)Stimulates uterine smooth muscle contraction.Labour induction, PPH prevention.10 IU IM/IV for PPH, 2 mU/min IV for induction.Previous uterine rupture, fetal distress.
Misoprostol (Cytotec)Prostaglandin E1 analog – stimulates contractions & cervical ripening.PPH treatment, medical abortion.600 mcg oral or 800 mcg PR for PPH, 200 mcg for induction.Asthma, uterine rupture risk, previous C-section.
Carboprost (Hemabate)Prostaglandin F2α analog – causes uterine contraction & vasoconstriction.PPH due to atony.250 mcg IM every 15 min (Max 8 doses).Asthma, cardiac disease.
Methylergonovine (Methergine)Ergot alkaloid – causes sustained uterine contractions.PPH due to atony.0.2 mg IM every 2–4 hrs (Max 5 doses).Hypertension, preeclampsia, heart disease.

Nursing Considerations:

  • Monitor uterine contractions & fetal heart rate (Oxytocin can cause fetal distress).
  • Avoid Methylergonovine in hypertensive patients.
  • Misoprostol can cause diarrhea, nausea – give fluids if needed.

Tocolytics (Drugs That Stop Uterine Contractions)

Definition:
Tocolytics are drugs used to delay preterm labour by inhibiting uterine contractions.

Common Tocolytics & Their Uses:

DrugMechanism of ActionIndicationsDosage & RouteContraindications
Nifedipine (Calcium Channel Blocker)Relaxes smooth muscle by inhibiting calcium influx.Preterm labour (first-line).10 mg oral every 20 min (Max 40 mg in 1 hour).Hypotension, cardiac disease.
Terbutaline (Beta-2 Agonist)Relaxes uterine muscle by stimulating beta-2 receptors.Acute preterm labour (rescue therapy).250 mcg SC every 20 min (Max 3 doses).Heart disease, diabetes (can cause tachycardia).
Magnesium SulfateCompetes with calcium to reduce uterine contractility.Preterm labour, neuroprotection in preterm babies.IV 4–6 g loading dose, then 1–2 g/hr infusion.Myasthenia gravis, renal failure.
Indomethacin (NSAID)Blocks prostaglandin synthesis, reducing uterine contractions.Preterm labour (before 32 weeks).50–100 mg rectal or 25 mg oral every 4–6 hrs.Peptic ulcers, renal disease.

Nursing Considerations:

  • Monitor maternal HR & BP (Nifedipine causes hypotension).
  • Assess for fetal distress if prolonged therapy is used.
  • Monitor magnesium toxicity (loss of reflexes, respiratory depression).

Cervical Ripening Agents

Definition:
Cervical ripening agents soften the cervix and induce dilation for labour induction.

Common Agents:

DrugMechanism of ActionDosage & RouteContraindications
Dinoprostone (Prostaglandin E2, Cervidil, Prepidil, Prostin)Stimulates cervical softening & uterine contractions.10 mg vaginal insert, removed after 12 hours.Previous C-section, uterine rupture risk.
Misoprostol (Cytotec)Prostaglandin E1 analog, causes cervical dilation.25 mcg vaginally every 4–6 hrs.Uterine hyperstimulation, previous uterine scar.

Nursing Considerations:

  • Monitor FHR & contractions for hyperstimulation.
  • Remove Dinoprostone if uterine tachysystole occurs (>5 contractions in 10 min).

Antihypertensives in Pregnancy

Definition:
Used to control gestational hypertension, preeclampsia, and eclampsia to prevent complications.

Common Drugs & Their Uses:

DrugMechanism of ActionIndicationsDosage & RouteContraindications
MethyldopaCentral α2 agonist, lowers BP.Chronic hypertension in pregnancy.250–500 mg oral 2–3 times/day.Liver disease.
LabetalolBeta-blocker, reduces BP without reducing uteroplacental flow.Preeclampsia, severe HTN.20 mg IV bolus, repeat every 10 min.Asthma, heart block.
NifedipineCalcium channel blocker, relaxes vessels.Gestational HTN.10–20 mg oral every 6 hrs.Severe hypotension.

Nursing Considerations:

  • Monitor BP, fetal well-being.
  • Avoid ACE inhibitors (teratogenic effects).

Drugs Used in Pre-Eclampsia & Eclampsia

Definition:
Pre-eclampsia is hypertension with proteinuria, while eclampsia includes seizures.

Drugs Used:

DrugMechanism of ActionIndicationsDosage & Route
Magnesium SulfateCNS depressant, prevents seizures.Eclampsia, severe preeclampsia.4 g IV loading, 1 g/hr infusion.
HydralazineDirect vasodilator.Severe hypertension.5–10 mg IV every 20 min.
LabetalolBeta-blocker.Preeclampsia.20 mg IV bolus, repeat as needed.

Nursing Considerations:

  • Monitor deep tendon reflexes (magnesium toxicity sign).
  • Keep calcium gluconate ready (antidote for magnesium toxicity).

Drugs for Pregnancy Termination

Used for medical abortion in early pregnancy.

DrugMechanism of ActionDosage & RouteUsed Up To
Mifepristone (RU-486)Progesterone antagonist, stops fetal growth.200 mg oral.Up to 9 weeks.
MisoprostolInduces contractions.800 mcg vaginally.Up to 9 weeks.

Nursing Considerations:

  • Monitor for excessive bleeding.
  • Ensure complete abortion (follow-up ultrasound).

Anti-D Immunoglobulin (RhoGAM)

Definition:
Used to prevent Rh isoimmunization in Rh-negative mothers carrying an Rh-positive fetus.

Indications:

  • Administered at 28 weeks gestation.
  • Given within 72 hours after delivery if the baby is Rh-positive.

Dosage:

  • 300 mcg IM.

Nursing Considerations:

  • Check blood type of mother and baby.
  • Monitor for allergic reactions.

Introduction to Magnesium Sulfate (MgSO₄)

Definition:
Magnesium sulfate (MgSO₄) is a CNS depressant and smooth muscle relaxant used to prevent and treat seizures in severe preeclampsia and eclampsia. It is also used for neuroprotection in preterm labour.

Drug Classification:

  • Class: Anticonvulsant, Tocolytic, Electrolyte replacement.
  • Pregnancy Category: Category A (Safe for pregnancy use in preeclampsia/eclampsia).

Mechanism of Action:

  • Inhibits neuromuscular transmission → Prevents seizures.
  • Relaxes smooth muscles → Lowers BP slightly (not a first-line antihypertensive).
  • Blocks calcium influx → Reduces uterine contractions in preterm labour.

Clinical Uses:

  1. Prevention and treatment of eclampsia (seizures in pregnancy).
  2. Neuroprotection for preterm infants (<32 weeks).
  3. Tocolytic (delays preterm labour).

Magnesium Sulfate Regimen in Preeclampsia & Eclampsia

Indications for Magnesium Sulfate Therapy:

  • Severe preeclampsia (BP ≥160/110 mmHg + proteinuria).
  • Eclampsia (seizures in pregnancy).
  • HELLP Syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets).

Dosage & Administration (Pritchard & Zuspan Regimens)

RegimenLoading DoseMaintenance DoseRoute
Pritchard Regimen (IM + IV)4 g IV over 10 min + 5 g IM in each buttock5 g IM every 4 hoursIV + IM
Zuspan Regimen (IV only)4–6 g IV over 15 min1–2 g/hr IV infusionIV infusion
Sibai Regimen (IV only, most preferred)6 g IV over 15 min2 g/hr IV infusionIV infusion

Timing of Administration:

  • Start immediately in eclampsia (after first seizure).
  • Continue for 24 hours postpartum or after the last seizure.

Nursing Considerations:

  • Give IV dose slowly (rapid infusion can cause hypotension).
  • Monitor vital signs every 15 minutes initially.
  • Check deep tendon reflexes (DTR) before each dose.

Monitoring for Magnesium Toxicity

Therapeutic Magnesium Level: 4–7 mEq/L

Signs of Magnesium Toxicity:

Serum Mg LevelToxic EffectsManagement
>7 mEq/LLoss of deep tendon reflexes (DTRs).Stop infusion, monitor.
>10 mEq/LRespiratory depression (RR <12).Administer oxygen, prepare for antidote.
>15 mEq/LCardiac arrest.Give calcium gluconate IV immediately.

Magnesium Toxicity Management:

  • Stop Magnesium Sulfate immediately.
  • **Administer 10 mL of 10% calcium gluconate IV slowly over 10 minutes.
  • Provide respiratory support if needed (oxygen, ventilation).

Nursing Responsibilities:

  • Assess deep tendon reflexes (DTRs) every 1–2 hours.
  • Monitor urine output (>30 mL/hr required for Mg excretion).
  • Watch for decreased respiratory rate (<12 breaths/min).
  • Keep calcium gluconate (10%) readily available at bedside.

Contraindications & Precautions

Absolute Contraindications:

  • Myasthenia gravis (Mg worsens muscle weakness).
  • Severe renal failure (risk of toxicity due to impaired excretion).
  • Heart block (Mg suppresses cardiac conduction).
  • Hypocalcemia (Mg competes with calcium).

Precautions:

  • Asthma (Mg may cause respiratory depression).
  • Use cautiously in oliguria (urine output <30 mL/hr).
  • Do not use as an antihypertensive (it’s NOT a BP-lowering drug).

Expected Outcomes of Magnesium Therapy

Therapeutic Effects:

  • Seizure prevention in eclampsia.
  • Reduced risk of cerebral hemorrhage.
  • Neuroprotection in preterm infants (decreases cerebral palsy risk).

Failure of Therapy:

  • Seizures persist despite correct dosage → Consider diazepam or phenytoin.

When to Stop Therapy:

  • No seizures for 24 hours postpartum.
  • BP stabilizes & proteinuria reduces.

Comparison with Other Anticonvulsants

DrugUse in EclampsiaAdvantagesDisadvantages
Magnesium SulfateFirst-line treatmentPrevents seizures, safer for fetus.Risk of toxicity.
DiazepamSecond-line (if Mg fails).Controls seizures quickly.Respiratory depression, neonatal sedation.
PhenytoinRarely used in eclampsia.Less sedation than diazepam.Less effective than MgSO₄.

Exam-Oriented Questions

What is the first-line drug for eclampsia?
👉 Magnesium sulfate.

What is the antidote for magnesium toxicity?
👉 Calcium gluconate (10 mL of 10% solution IV).

What is the therapeutic range of magnesium in eclampsia treatment?
👉 4–7 mEq/L.

What is the first sign of magnesium toxicity?
👉 Loss of deep tendon reflexes (DTRs).

What is the loading dose of magnesium sulfate in eclampsia?
👉 4–6 g IV over 15 minutes.

What is the maintenance dose of magnesium sulfate?
👉 1–2 g/hr IV infusion for 24 hours.

Why is magnesium sulfate preferred over diazepam in eclampsia?
👉 Better seizure prevention, fewer side effects on the fetus.

Midwifery & Obstetric Surgeries

These surgeries are performed during pregnancy, labour, and postpartum periods to ensure maternal and fetal well-being.

1.1. Cesarean Section (C-Section)

Definition:
A surgical procedure where the baby is delivered through an incision in the abdomen and uterus.

Types:

TypeIncision TypeClinical Significance
Lower Segment Cesarean Section (LSCS)Transverse incision on the lower uterine segmentPreferred due to less bleeding, faster healing, and lower rupture risk in future pregnancies.
Classical Cesarean SectionVertical incision on the upper uterine segmentHigher rupture risk in future pregnancies. Used only in emergencies.

Indications:

  • Fetal Distress (Abnormal CTG, Meconium-stained liquor).
  • Cephalopelvic Disproportion (CPD) – Baby’s head is too large.
  • Previous C-section (risk of uterine rupture in vaginal delivery).
  • Placenta Previa (placenta covering cervix).
  • Failure to progress in labour.

Procedure:

  1. Anesthesia (Spinal/Epidural or General in emergencies).
  2. Skin Incision (Pfannenstiel – Transverse, or Midline – Vertical).
  3. Uterine Incision & Fetal Delivery.
  4. Placental Delivery & Uterine Closure.
  5. Abdominal Closure (Peritoneum, Muscle, Fascia, Skin).

Complications:

  • Maternal: Hemorrhage, Infection, Blood clots, Uterine rupture in future pregnancy.
  • Neonatal: Respiratory distress, Injury during surgery.

Nursing Care Post C-Section:

  • Monitor for PPH, infection, pain.
  • Encourage early ambulation to prevent DVT.
  • Assess breastfeeding readiness.

1.2. Episiotomy

Definition:
A surgical incision made on the perineum to enlarge the vaginal opening during delivery.

Types of Episiotomy:

TypeIncision DirectionClinical Significance
MidlineStraight cut from vaginal opening to perineumEasier to repair but higher risk of 4th-degree tear.
MediolateralCut at a 45° angleLess risk of rectal tear but more painful.

Indications:

  • Prolonged second stage of labour.
  • Fetal distress needing rapid delivery.
  • Instrumental delivery (forceps, vacuum).
  • Rigid perineum preventing normal birth.

Procedure:

  1. Local anesthesia (Lidocaine).
  2. Surgical incision during crowning.
  3. Delivery of baby.
  4. Suturing of perineal layers.

Complications:

  • Infection, Hematoma, Painful intercourse (dyspareunia).
  • Delayed healing if poor perineal hygiene.

Nursing Care:

  • Sitz baths, perineal hygiene, ice packs for swelling.
  • Pelvic floor exercises for perineal strengthening.

1.3. Dilatation and Curettage (D&C)

Definition:
A surgical procedure to remove the uterine contents using dilatation of the cervix and scraping (curettage).

Indications:

  • Incomplete abortion (removal of retained products).
  • Abnormal uterine bleeding (for diagnosis or treatment).
  • Molar pregnancy evacuation.
  • Endometrial biopsy for cancer screening.

Procedure:

  1. Cervical dilatation (using rods or Misoprostol).
  2. Curettage (Scraping of the uterine lining).
  3. Hemostasis and closure.

Complications:

  • Uterine perforation, Infection, Heavy bleeding, Asherman’s Syndrome (intrauterine adhesions).

Nursing Care:

  • Monitor bleeding, signs of infection.
  • Avoid tampon use, intercourse for 2 weeks.

2. Gynecological Surgeries

These surgeries diagnose and treat reproductive system disorders.

2.1. Hysterectomy (Uterus Removal)

Definition:
Hysterectomy is the surgical removal of the uterus (with or without ovaries and fallopian tubes).

Types of Hysterectomy:

TypeStructures RemovedIndications
Total HysterectomyUterus & CervixFibroids, Endometriosis, Uterine prolapse.
Subtotal HysterectomyOnly UterusRetains cervix for pelvic support.
Radical HysterectomyUterus, Cervix, Lymph nodesCervical cancer.
Hysterectomy with Salpingo-OophorectomyUterus, Fallopian Tubes, OvariesOvarian cancer, BRCA mutation.

Surgical Approaches:

  • Abdominal (Laparotomy) – Preferred for large masses.
  • Vaginal – Less invasive, quicker recovery.
  • Laparoscopic/Robotic – Minimally invasive, less pain.

Complications:

  • Hemorrhage, Infection, Bladder Injury, Early Menopause (if ovaries removed).

Nursing Care:

  • Monitor for bleeding, infection, urinary retention.
  • Early ambulation to prevent DVT.

2.2. Oophorectomy (Ovary Removal)

Indications:

  • Ovarian cysts or tumors.
  • Ovarian cancer.
  • BRCA gene mutation (for risk reduction).

Types:

  • Unilateral (One ovary removed).
  • Bilateral (Both ovaries removed → Early menopause).

Post-Surgical Care:

  • Monitor estrogen deficiency symptoms (hot flashes, osteoporosis).
  • Hormone replacement therapy (HRT) if needed.

2.3. Salpingectomy (Fallopian Tube Removal)

Indications:

  • Ectopic pregnancy (ruptured tube).
  • Hydrosalpinx (fluid-filled tube causing infertility).
  • Prophylactic removal in BRCA mutation carriers.

Surgical Approaches:

  • Laparoscopic (preferred).
  • Open surgery (if ruptured ectopic pregnancy).

Nursing Care:

  • Monitor for shock if done in emergency.
  • Counsel on fertility loss if both tubes removed.

2.4. Laparoscopy in Gynecology

Definition:
A minimally invasive procedure to examine and treat pelvic pathology using a camera (laparoscope).

Indications:

  • Endometriosis diagnosis.
  • Ovarian cystectomy.
  • Tubal ligation (sterilization).

Procedure:

  1. CO₂ gas insufflation to create space.
  2. Insertion of laparoscope through small incisions.
  3. Surgical treatment as needed.

Complications:

  • Gas embolism, Organ injury, Post-op shoulder pain (due to CO₂ gas).

Post-Op Care:

  • Encourage early mobilization to relieve gas pain.
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Categorized as COH MIDWIFERY, Uncategorised