Valerie Hill - Complications

Dystocia

Abnormally slow progress of labor. Defined as >4 hours of less than 0.5cm per hour of dilation, OR >1 hour of active pushing with no descent of the presenting part.

Uterine Abnormalities that Cause Dystocia in the First and Second Stages of Labour

• In the latent first stage of labor, patients may experience hypertonic uterine dysfunction as a byproduct of anxiety and pain. The contractions may be uncoordinated and not near the fundus, leading to pain without progress. The uterus may also not be relaxing. Helping patients rest and relax can help to lead them to normal active labor.

• In the active phase, patients may have protraction disorders (slower than normal progress), or arrest disorders (no progress). This can be caused by hypotonic uterine dysfunction, where contractions become weak, inefficient or stop in the active stage. The uterus is soft even during a contraction. Abnormal fetal presentation can be a cause of this. Treatment can be augmentation measures to increase progress.

Precipitous Labour

Labor that lasts <3 hours from the onset of contractions to the time of birth. Can be caused by hypertonia, tetany and uterine tachystole.

How is a Patient Prepped for Induction of Labour

• When labor is artificially induced due to maternal or fetal circumstance. AROM is initiated and the cervix is ripened before oxytocin is started, cervical ripeness is the most important predictor of successful induction and can be rated through the bishop score (should be >7). Prostaglandins are used for cervical ripening.

Mechanical Dilators for Induction of Labour

• Uterine dilation can also occur through mechanical and physical dilators. Such methods include a foley catheter which is inflated just above the cervix and exerts pressure on the cervix and allows for the release of endogenous prostaglandins. Other methods include synthetic and natural hydroscopic dilators which are inserted into the endocervix and expand as they absorb fluid. These methods are contraindicated in low lying placentas. Mechanical methods are less likely to cause tachystole than prostaglandins are.

Membrane Sweeping

Membrane sweeping is a method of induction where a finger is inserted into the internal cervical os, and rotated 360 degrees to separate the amniotic sac. This causes release of endogenous prostaglandins.

Types of Skin and Uterine Incisions in a C Section

• Skin incision can be vertical (from umbilicus to pubic bone) or low transverse (more common).

• Uterine incision can be vertical (attempts to avoid the muscular part of the uterus but that doesn’t always happen), or transverse. Transverse is much preferred but in some cases can be contraindicated (ex: Transverse presentation, or low placenta). Vaginal birth after a classic/vertical incision is contraindicated as vertical incisions increase risk of uterine rupture.

• If a patient is attempting VBAC, oxytocin should be used with caution (mixed evidence for uterine rupture), but prostaglandins should not be used (can cause rupture).

Meconium Stained Amniotic Fluid

• For whatever reason (maturity, hypoxia induced peristalsis, or cord compression), the baby has passed the first stool (meconium) while in the uterus. 

• This is an emergency because the baby can aspirate meconium, resulting in a very severe form of aspiration pneumonia.

Shoulder Dystocia

• Shoulder stuck behind the symphysis pubis, resulting in the baby being unable to pass through the birth canal. Can result in many complications

• Maneuvers to remove a baby can cause fetal complications such as broken limbs, or brachial plexus injury (Erb’s palsy). Most cases of Erb’s Palsy can be resolved completely with management though.

• The McRoberts maneuver + suprapubic pressure is the most common response to shoulder dystocia, and involves mom taking her knees to her chest while suprapubic pressure is applied.

• The gaskin maneuver (hands and knees position) is also common

Prolapse of the Umbilical Cord

• Can be occult or visible

• Longer cord, or the presenting part not being snug against the lower uterine segment (polyhydramnios, preterm, unengaged presenting part, high baby, etc) can increase risk of this as when membranes rupture the cord slips through.

• Emergency

Uterine Rupture

• All layers of the uterus open, leading to hemorrhage and fetal and maternal risks. Most often caused by previous scars.

• Uterine dehiscence is where a scar partially opens, but not through all the layers of the uterus (uterine window).

• Emergency