Uterine Motility Drug
Name
Oxytocics
Indication
Mehanism of action
Therapeutic of action
To stimulate uterine contractions like the action of the hypothalamic hormone oxytocin stored in the posterior pituitary.
They directly affect neuroreceptor sites to stimulate uterine contraction and are especially effective in the gravid uterus.
Oxytocin, a synthetic form of the hypothalamic hormone, also stimulates the lacteal glands in the breast to contract, promoting milk ejection in lactating women.
Prevention and treatment of uterine atony after delivery, thus reducing the risk of postpartum hemorrhage.
Contraindication and caution
Allery to oxytocics. Prevent hypersensitivity reactions.
Cephalopelvic disproportion, unfavorable fetal position, complete uterine atony, early pregnancy. Can be compromised by uterine stimulation.
Coronary disease, hypertension. Due to effect of causing arterial contraction which could raise blood pressure or compromise coronary blood flow.
Adverse affects
Excessive effects: uterine hypertonicity and spasm, uterine rupture, postpartum hemorrhage, decreased fetal heart rate
Common effects: GI upset, nausea, headache, dizziness
Ergotism caused by ergonovine and methylergonovine: nausea, blood pressure changes, weak pulse, dyspnea, chest pain,
Oxytocin has caused severe water intoxication with coma and even maternal death when used for a prolonged period.
Nursing assessment
Assess for the mentioned cautions and contraindications to prevent any untoward complications.
Perform a thorough physical assessment to establish baseline data before drug therapy begins, to determine effectiveness of therapy
to evaluate for occurrence of any adverse effects associated with drug therapy.
Monitor laboratory test results (e.g. coagulation studies, complete blood count, etc.) to evaluate hematological studies.
Nursing diagnoses
Acute pain related to increased frequency and intensity of uterine contractions or headache
Excess fluid volume related to ergotism or water intoxication
Implementation of rationale
Ensure fetal position (if appropriate) and cephalopelvic proportions to prevent serious complications of delivery.
Monitor blood pressure and fetal heart rate frequently during and after administration to monitor for adverse effects.
Monitor uterine tone and involution and amount of bleeding to ensure safe and therapeutic drug use.
Provide comfort measures to help patient tolerate drug effects.
References
Kosfeld M, Heinrichs M, Zak PJ, Fischbacher U, Fehr E: Oxytocin increases trust in humans. Nature. 2005 Jun 2;435(7042):673-6
Carmichael MS, Humbert R, Dixen J, Palmisano G, Greenleaf W, Davidson JM: Plasma oxytocin increases in the human sexual response. J Clin Endocrinol Metab. 1987 Jan;64(1):27-31
Oxytocin has specific receptors in the muscle lining of the uterus and the receptor concentration increases greatly during pregnancy, reaching a maximum in early labor at term.
Oxytocin promotes contractions by increasing the intracellular Ca2+, which in turn activates myosin's light chain kinase
Uterine motility depends on the formation of the contractile protein actomyosin under the influence of the Ca2+-dependent phosphorylating enzyme myosin light-chain kinase