Oxytocin fetal effects

If contractions are frequent, prolonged, or excessive, die infusion is stopped to prevent fetal anoxia or trauma to die uterus. Excessive stimulation of die uterus can cause uterine hypertonicity and possible uterine rupture. The nurse places die patient on her side and provides supplemental oxygen. The effects of die drug diminish rapidly because oxytocin is short acting. 

Inappropriate use of oxytocin can lead to uterine rupture, anaphylactoid and other allergic reactions, and possibly maternal death. Prolonged stimulation of uterine contractions can result in the following fetal adverse reactions persistent uteroplacental insufficiency, sinus bradycardia, premature ventricular contractions, other arrhythmias, and fetal death. Prolonged use of oxytocin can lead to water intoxication secondary to the antidiuretic hormone-like effects of oxytocin. Maternal and fetal cardiovascular parameters should be monitored during oxytocin administration. 

Theoretically, PGE2 and PGF2K should be superior to oxytocin for inducing labor in women with preeclampsia-eclampsia or cardiac and renal diseases because, unlike oxytocin, they have no antidiuretic effect. In addition, PGE2 has natriuretic effects. However, the clinical benefits of these effects have not been documented. In cases of intrauterine fetal death, the prostaglandins alone or with oxytocin seem to cause delivery effectively. 

Swanson LW, McKellar S (1979) Distribution of oxytocin-stained and neurophysin-sttiined fibers in the spinal-cord of the rat and monkey. J Comp Neurol 188 87-106 Sweeney MI, White TD, Sawynok J (1987) Involvement of adenosine in the spintd tmtinociceptive effects of morphine and noradrenaline. J Pharmacol Exp Ther 243 657-665 Szabo B (2008) Pharmacology of cannabinoid receptors. Biotrend Rev 2 1—13 Szabo C (2007) Hydrogen sulphide and its therapeutic potential. Nat Rev Drug Discov 6 917-935 Szeto HH (2003) Dynorphin and the hypothalamo-pituitary-adrenal axis during fetal development. Life Sci 73 749-758... 

Oxytocin is a hypothalamic nonapeptide that selectively stimulates the smooth muscle of the uterus and mammary glands. It is used in the induction or augmentation of labor and to prevent postpartum hemorrhage, and is well tolerated and effective in a wide range of infusion rates and concentrations. Contraindications to its use include placenta previa or vasa previa, a previous classical uterine incision, pelvic structural deformities, and an abnormal fetal presentation. Large fetal size and high maternal parity are relative contraindications. Prior non-classical cesarean delivery should not preclude oxytocin therapy. 

Ousey J C, Rossdale P D, Palmer L et al 2000 Effects of maternally administered depot ACTH(1-24) on fetal maturation and the timing of parturition in the mare. Equine Veterinary Journal 32 489-496 Pashen R L 1982 Oxytocin the induction agent of choice in the mare Journal of Reproduction and Fertility Supplements 32 645... 

AUGMENTATION OF DYSFUNCTIONAL LABOR To augment hypotonic contractions in dysfunctional labor, it rarely is necessary to exceed an infusion rate of 10 mlU/min, and doses of >20 mlU/min rarely are effective when lower concentrations fail. Potential complications of overstimulation include trauma of the mother or fetus due to forced passage through an incompletely dilated cervix, uterine rupture, and compromised fetal oxygenation due to decreased uterine perfusion. Oxytocin usually is effective when there is a prolonged latent phase of cervical dilation and when, in the absence of cephalopelvic disproportion, there is an arrest of dilation or descent. 

S X rd 0 IV/IM/nasal. Short half-life (3-5 min.). Potential for uterine tetany or rupture, trauma to infant, post -delivery uterine atony. Prolonged infusion (>24h) may cause water intoxication (antidiuretic activity). Potentiates hypertensive effects of other drugs. May cause stroke/hemorrhage, fetal distress. Synthetic oxytocin mimics the effects of endogenous oxytocin which is released from the hypothalamus. 

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