Dinoprostone (PGE2; Prostaglandin E2)

 Action Stimulates gravid uterus to contract; also stimulates smooth muscle of GI tract.

 Indications

Gel: Cervical ripening in pregnant women at or near term with need for labor induction. Vaginal suppositories: Termination of pregnancy from 12 to 20 wk.

 Contraindications Hypersensitivity to prostaglandins; patients in whom oxytocic drugs are contraindicated or when prolonged contractions of uterus are considered inappropriate; ruptured membranes; placenta previa; unexplained vaginal bleeding during current pregnancy; when vaginal delivery is not indicated; acute pelvic inflammatory disease; active cardiac, pulmonary, renal or hepatic disease.

 Route/Dosage

Cervical Ripening

ADULTS: Intravaginal Gel 0.5 mg (contents of one syringe); may repeat dose 6 hr later if necessary (maximum dose 1.5 mg (3 syringes/24 hr). Intravaginal Insert 10 mg (1 insert). Releases » 0.3 mg/hr over 12 hr. Remove insert upon onset of active labor or 12 hr after insertion.

Termination of Pregnancy

ADULTS: Intravaginal 1 suppository (20 mg) high into vagina. Repeat at 3 to 5 hr intervals until abortion occurs. Do not give continuously for > 2 days.

 Interactions

Oxytocic agents: May augment effect of other oxytocic agents; avoid concomitant use.

 Lab Test Interferences None well documented.

 Adverse Reactions

CV: Transient fall in BP; syncope; dizziness; arrhythmias. CNS: Headache; flushing; anxiety; tension; hot flashes; paresthesia; weakness. EENT: Blurred vision; eye pain. GI: Anorexia; nausea; vomiting; diarrhea. GU: Uterine contractile abnormality; endometritis; uterine rupture; uterine pain; amnionitis; premature rupture of membranes; vaginal pain; warm feeling in vagina. RESP: Bronchospasm; coughing; dyspnea; wheezing. OTHER: Back pain; muscular cramps; fever; chills; joint inflammation; breast tenderness; diaphoresis; rash; leg cramps; dehydration. Fetal effects: Fetal heart rate abnormalities; bradycardia; deceleration; sepsis; depression (1 min Apgar <7); acidosis.

 Precautions

Pregnancy: Category C. Contraindicated if fetus in utero has reached viability stage except when cervical ripening is indicated. Lactation: Undetermined. Special risk patients: Use with caution in patients with asthma, glaucoma, or raised intraocular pressure, hypotension or hypertension, cardiovascular or renal or hepatic dysfunction, anemia, jaundice, diabetes, epilepsy, compromised uterus, infected endocervical lesions; acute vaginitis.

 Administration/Storage

• Store suppository and insert in freezer. Store gel in refrigerator. Bring both to room temperature just prior to use, do not use external sources of heat (eg, hot water bath or microwave oven) to decrease warming time.
• Carefully examine vagina to determine degree of effacement and appropriate length of endocervical catheter to be used for application of gel (10 mm if 50% effaced, 20 mm if no effacement).
• Patient should be in dorsal position for administration and remain supine for 15 to 30 min after administration.
• Prevent contact of this drug with skin. Use of latex gloves followed by thorough hand washing with soap and water are recommended.
• Drug should be used in hospital setting only.

 Assessment/Interventions

• Obtain patient history, including drug history and any known allergies.
• Perform physical assessment to determine baseline vital signs and fetopelvic relationships.
• Perform careful uterine and fetal monitoring throughout use of dinoprostone.
• Wait ³ 6 to 12 hr after administration of gel before using IV oxytocin, a dosing interval of ³ 30 mins is recommended after removal of insert.
• Monitor patient closely for adverse reactions including nausea, vomiting or diarrhea.
• Monitor vital signs frequently during administration, noting especially any increase in temperature and hypertension or hypotension.
• Monitor for hypersensitivity reactions such as bronchospasms, cardiac arrhythmias or seizures. Notify physician should any of these symptoms occur.

 Patient/Family Education

• Inform patient of expected action and possible adverse reactions with drug.
• Inform patient that uterine contractions are expected and that if pain from contractions becomes severe, physician will be notified to obtain order for analgesic.
• Instruct patient to report these symptoms to nurse immediately: nausea, vomiting, difficulty breathing, chest pain or headache.