Central to the management of dystocia is augmentation of labor, that is, correcting ineffective uterine contractions. Despite vast experience with labor. 49, December Dystocia and Augmentation of Labor. First published: 12 May (04) Cited by: 4. About. diagnosis and management of dystocia, including a range of acceptable methods of augmentation of labor. Normal labor. Labor commences when uterine.
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ACE inhibitors should not be continued in pregnancy. Beta-blockers are generally considered to be safe, augmenattion they may impair fetal growth when used early in pregnancy, particularly atenolol. Labetalol is the preferred agent. The normal fall in blood pressure during the second trimester may allow a reduction in drug dosage or even cessation of therapy.
Start treatment with dystocoa labetolol or methyldopa. A long-acting calcium augmentaiton blocker eg, nifedipine or amlodipine can be added as either secondor third-line treatment. The goal of therapy in women without end-organ dyetocia is systolic pressure between and mm Hg and diastolic pressure between lagor and mm Hg.
Frequent prenatal visits for monitoring maternal blood pressure, proteinuria, and fundal growth and by periodic sonographic estimation of fetal size are recommended. A baseline ultrasound examination is recommended at 16 to 20 weeks of gestation to confirm gestational age.
A nonstress test or biophysical profile should be performed weekly starting at 32 weeks. Woman with mild, uncomplicated chronic hypertension can be allowed to go into spontaneous labor and deliver at term. Earlier delivery can be considered for women with severe hypertension, superimposed preeclampsia, or pregnancy complications eg, fetal growth restriction, previous stillbirth.
The preferred agents are methyldopa for prolonged antenatal therapy, and hydralazine, labetalol or nifedipine for peripartum treatment of acute hypertensive episodes. Sodium restriction and diuretics have no role in therapy. Restricted physical activity can lower blood pressure. The first stage of labor consists of the period from the onset of labor until complete cervical dilation 10 cm.
This stage is divided into the latent phase and the active phase. During the latent phase, uterine contractions are infrequent and irregular dhstocia result in only modest discomfort. They result in gradual effacement and dilation of the cervix. A prolonged latent phase is one that exceeds 20 hours in the nullipara or one that exceeds 14 hours in the multipara. The active phase of labor occurs when the cervix reaches cm of dilatation. The active phase of labor is characterized by an increased rate of cervical dilation and by descent of the presenting fetal dystodia.
The second stage of labor consists of the period from complete cervical dilation 10 cm until delivery of the infant. This stage is usually brief, averaging 20 minutes for parous women lagor 50 minutes for nulliparous women.
The duration of the second stage of labor is unrelated to perinatal outcome in the absence of dysgocia nonreassuring fetal. Dystocia is defined as difficult labor or childbirth resulting from abnormalities of the cervix and uterus, the fetus, the maternal pelvis, or a combination of these factors. Cephalopelvic disproportion is a disparity between the size of the maternal pelvis and the fetal head that precludes vaginal delivery.
This condition can rarely be diagnosed in advance. Slower-than-normal protraction disorders or complete cessation of progress arrest disorder are disorders that can be diagnosed only after the parturient has entered the.
Assessment of labor abnormalities. Labor abnormalities caused by inadequate uterine contractility powers. The minimal uterine contractile pattern of women in spontaneous labor consists of 3 dystocai 5 contractions in a minute period. Labor abnormalities caused by fetal characteristics passenger. Assessment of the fetus consists of estimating fetal weight and position.
Estimations of fetal size, even those obtained by ultrasonography, are frequently inaccurate. In the first stage of labor, the diagnosis of dystocia can not be made unless the active phase of labor and adequate uterine contractile forces have been present.
Fetal anomalies such as hydrocephaly, encephalocele, and soft tissue tumors may obstruct labor. Fetal imaging should be considered when malpresentation or anomalies are suspected based on vaginal or abdominal examination or when the presenting fetal part is persistently high.
Dystocia and Augmentation of Labor
Labor abnormalities due to the pelvic passage passage. Inefficient uterine action should be corrected before attributing dystocia to a pelvic problem.
The bony pelvis is very rarely the factor that limits vaginal delivery of a fetus in cephalic presentation. Clinical pelvimetry can only be useful to qualitatively identify the general architectural features of the pelvis. Uterine hypocontractility should be augmented only after both the maternal pelvis and fetal presentation have been assessed. Contraindications labo augmentation include placenta or vasa dystocka, umbilical cord prolapse, prior classical uterine incision, pelvic structural deformities, and invasive cervical cancer.
Dystocia and Augmentation of Labor
The goal of oxytocin administration lbor to stimulate uterine activity that is sufficient to produce cervical change and fetal descent while avoiding uterine hyperstimulation and fetal compromise. Minimally effective uterine activity is 3 contractions per 10 minutes averaging greater than 25 mm Hg above baseline. A maximum of 5 contractions in a minute period with resultant cervical dilatation is considered adequate.
Hyperstimulation is characterized by more than five contractions in 10 minutes, contractions lasting 2 minutes or more, or aumentation of normal duration occurring within 1 minute of each other. Oxytocin is administered when a patient is progressing slowly through the latent phase of labor or has a protraction or an arrest disorder of labor, or when a hypotonic uterine contraction pattern is identified. A pelvic examination should be performed before initiation of oxytocin infusion. Oxytocin is usually diluted 10 units in 1 liter of normal saline IVPB.
Management of oxytocin-induced hyperstimulation. The most common adverse effect of hyperstimulation is fetal heart rate deceleration associated with uterine hyperstimulation. Stopping or decreasing the dose of oxytocin may correct the abnormal pattern.
Additional measures may include changing the patient to the lateral decubitus position and administering oxygen or more intravenous fluid. If oxytocin-induced uterine hyperstimulation does not respond to conservative measures, intravenous. Shoulder dystocia, defined as failure of the shoulders to deliver following the head, is an obstetric emergency. The incidence varies from 0.
Most commonly, size discrepancy secondary to fetal macrosomia is associated with difficult shoulder delivery. Causal factors of macrosomia include maternal diabetes, postdates gestation, and obesity.
The fetus of the diabetic gravida may also have disproportionately large shoulders and body size compared with the head. The diagnosis of shoulder dystocia is made after delivery of the head. This sign demonstrates that the shoulder girdle is resisting entry into systocia pelvic inlet, and possibly impaction of the anterior shoulder.
Kf has the strongest association.
dystcoia Risk factors for macrosomia include maternal birth weight, prior macrosomia, preexisting diabetes, obesity, multiparity, advanced maternal age, and a prior shoulder dystocia. The recurrence rate has been reported to be Shoulder dystocia occurs in 5. In the antepartum period, risk factors include gestational diabetes, excessive weight gain, short stature, macrosomia, and dyatocia pregnancy. Intrapartum factors include prolonged second stage of labor, abnormal first stage, arrest disorders, and instrumental especially midforceps delivery.
Many shoulder dystocias will occur in. Shoulder dystocia is a medical and possibly surgical emergency. Two assistants should be called for if not already present, as well as an anesthesiologist and pediatrician. A generous episiotomy should be cut. The following sequence is suggested: The legs are removed from the lithotomy position and flexed at the hips, with flexion of the knees augmentatioon the abdomen.
Two assistants are required. This maneuver may be performed prophylactically in anticipation of a difficult delivery. An assistant is requested to apply pressure downward, above the symphysis pubis. This can be done in a lateral direction to help dislodge the anterior shoulder from behind the pubic symphysis. It can also be performed in anticipation of a difficult delivery. Fundal pressure may increase the likelihood of uterine rupture.
The Woods’ corkscrew maneuver consists of placing two fingers against the anterior aspect of the posterior shoulder. Gentle upward rotational pressure is applied so that the posterior shoulder girdle rotates anteriorly, allowing it to be delivered first.
The Rubin maneuver is the reverse of Woods’s maneuver. Two fingers are placed against the posterior aspect of the posterior or anterior shoulder and forward pressure applied. This results in adduction of the shoulders and displacement of the anterior shoulder from behind the symphysis pubis.
The operator places a hand into the posterior vagina along the infant’s back.
ACOG Practice Bulletin Number 49, December 2003: Dystocia and augmentation of labor.
The posterior arm is identified and followed dystocua the elbow. The elbow is augmenttation swept across the chest, keeping the elbow flexed. The fetal forearm or hand is then grasped and the posterior arm delivered, followed by the anterior shoulder. If the fetus still remains undelivered, vaginal delivery should be abandoned and the Zavanelli maneuver performed followed by cesarean delivery.
The fetal head is replaced into the womb. Tocolysis is recommended to produce uterine relaxation. The maneuver consists lf rotation of the head to occiput anterior. The head is then flexed and pushed back into the vagina, followed abdominal delivery.
Immediate preparations should be made for cesarean delivery. If cephalic replacement fails, an emergency symphysiotomy should be performed.
The urethra should be laterally displaced to minimize the risk of lower urinary tract injury. Induction of labor refers to stimulation of uterine contractions prior to the onset of spontaneous labor.