| SODIUM CHLORIDE 20%
Sodium Chloride 20%
Classifications: abortifacient; Therapeutic: abortifacient
Pregnancy Category: X
Hypertonic saline instillation into the amniotic sac induces abortion and fetal death. Mechanism is unclear, but abortifacient
activity may be a response to prostaglandins released by hypertonic NaCl-damaged cells.
Uterine contractions induced by the saline solution are sufficient to cause evacuation of fetus and placenta; however, in
2540% of the patients, abortion may be incomplete.
To induce abortion late in the second trimester of pregnancy. Oxytocin may be used as an adjunct (concurrent) uterine stimulant.
Pregnancy (category X) of less than 15 wk or more than 24 wk; prior uterine surgery (including cervix), pelvic adhesions;
sickle cell disease, diabetes mellitus; increased intraamniotic pressure (as in contracting or hypertonic uterus); poor
health, blood disorders, coagulation factor deficiencies.
Malignant hypertension, cardiovascular and kidney disease, thrombocytopenia, fibrinolytic defects.
Route & Dosage
Adult: Instillation Intraamniotic with 20% solution in volumes equal to amount of amniotic fluid removed (max: 200250 mL) administered
slowly over 2030 min; repeat in 48 h if uterine contractility, cervical effacement, or cervical dilation is inadequate
or if labor has not begun
- Prepare skin as for surgery prior to procedure. Withdraw about 1 mL of amniotic fluid by transabdominal tap to confirm location
of needle (amniotic fluid has pH 7.4 and ability to fern). If blood is present or if no amniotic fluid is withdrawn, needle
is repositioned. Some clinicians then remove all amniotic fluid (30250 mL); others wait until NaCl instillation.
- Instill NaCl through 3-way stopcock with needle and polyethylene catheter inserted into amniotic cavity.
- Administer IV infusion of dilute solution of oxytocin within 12 h after hypertonic solution instillation and after
uterine response to the solution has ceased at rate, 20100 mU/min. Oxytocin action as an adjunctive uterine stimulant
shortens the abortifacient-abortion interval.
- Be prepared to treat extraamniotic injection: Stop procedure promptly. Start IV infusion of D5W; additional support for
Adverse Effects (≥1%)Hematologic:
(Within 1224 h of instillation) Coagulation changes; increased plasma
volume, fibrin levels, thrombin
and partial thromboplastin times; mild self-limiting form of disseminated
intravascular coagulation. Metabolic:
Ascites, hypervolemia, circulation failure, uterine necrosis,
severe electrolyte disturbances. Urogenital:
Cervical lacerations and perforation, uterine rupture, retained placenta, hemorrhagic fever, infection
, sepsis. Respiratory: Pulmonary embolism. Body as a Whole:
Fever, flushing, cortical necrosis of kidneys.
may delay onset time of abortion; terbutaline, ritodrine
inhibit uterine activity induced by hypertonic NaCl.
Some drug diffuses into maternal blood. Onset:
Within 51 h. Distribution:
Sodium concentration in amniotic fluid must be at least 2.2 mEq/mL to induce abortion; most of drug concentrates in decidua
and fetal part of placenta.
Assessment & Drug Effects
- Observe patient for at least 30 min after instillation procedure. Be available for complaints and to check vital signs:
temperature, pulse rate, BP.
- Note: Intraamniotic instillation is a painless procedure. No anesthetic or sedative is needed or given so that patient is able
to report early signs of extraamniotic injection including mental confusion, hypotension, severe headache, vague distress,
extreme nervousness, pain, sensation of heat, thirst, fingertip numbness, dry mouth, salty taste, tinnitus.
- Suspect accidental intraperitoneal, intravascular, or myometrial injection if patient begins vomiting. Cardiovascular collapse,
seizures, and maternal death may follow.
Patient & Family Education
- Drink at least 2 L water on day of procedure to promote NaCl excretion.
- Return promptly to treatment center with onset of labor, signs of rupture of fetal membrane, vaginal bleeding, fever, or
any other untoward symptom.
- Return to physician for evaluation and treatment if labor has not begun within 48 h of hypertonic saline instillation.