MANAGEMENT OF ABNORMAL LABOR

Definitions:

👉 Cephalopelvic Disproportion:

Defined as the relationship of the fetal head and the pelvis bone. It might be the fetal head is large despite the normal pelvis or the head may be medium but the pelvis is abnormal with less measurements.

👉 Dystocia :

is defined as difficult labor and is characterized by abnormally slow progress of labor. Abnormal labor ,also called dystocia;

Abnormal labor:

Is very common whenever there is disproportion between the presenting part of the fetus and the birth canal.

➡️ MAJOR INFLUENCING FACTORS

There are three major influencing factors.

When one or more factors abnormal or uncoordinated as abnormal labor. that may exist singly or in combination.

Categories /types of dystocia :

(1) Abnormalities of the powers (uterine contractility and maternal expulsive effort)either uterine forces insufficiently strong or inappropriately coordinated to efface and dilate the cervix — uterine dysfunction — or inadequate voluntary muscle effort during the second stage of labor.

(2) Abnormalities of passenger (the fetus) excessive fetal size , malpositions ,congenital anomalies , multiple gestation

(3) Abnormalities of the passage (the birth

canal) pelvic contraction , soft tissue abnormalities of the birth canal , masses or neoplasia , abnormal placental location

(4) Abnormalities of the powers

-uterine inertia

(i).Etiology of uterine inertia:

Cephalopelvic disproportion or Fetal malposition

Abnormal of uterine muscle

Administration of analgesia

Others;

Absence of effective uterine contractions during labor;

Primary uterine inertia

Uterine inertia that occurs when the uterus fails to contract with sufficient force to effect continuous dilation or effacement of the cervix or descent

Secondary uterine inertia

uterine inertia that occurs when the uterine contractions are initially vigorous but then decrease in vigor, and the progress of labor ceases.

All these can be due to;

-Cephalopelvic disproportion

or Fetal malposition :

-The fetal head or presenting part could not close presses to the cervix and lower uterine segment.

-fetopelvic disproportion arises from diminished pelvic capacity, excessive fetal size, or malpresentation

Abnormal of uterine muscle:

-Uterine muscle malfunction can result from uterine over distention or obstructed labor, or both.

-Muscle fiber excessive elongation and contractility decline .

-Polyhydramnios,macrosomia,Multiple births (twins).

Abnormal of uterine muscle:

-Muscle fiber degeneration (Past history of repeat uterus infection,abortion , induction of labor ,or operation),

-myoma ,pelvic tumors, myogenic dysplasia or malformed uterus

psychical-factors:

-Fearing labor pain , anxiety, tension

Worried about fetal safety, labor hemorrhage, injury and dystocia. Which eventually lead to Uterine dysfunction and causes uterine inertia

Other factors:

hormonal mechanism of uterine activity

(deficiency of oxytocin , estradiol, prostaglandin)

excessive sedation ,anesthesia ,unripe cervix

fatigue , early abdominal pressure,

overactive bladder filling (fetal

presentation descent) .

🔻Diagnosis:

-hypotonic uterine dysfunction (coordinated):

Usually there is normal uterine contraction and maintain the polarity , symmetry, and a certain rhythm, but the contraction is weak and feeble, with short duration , long Interval and irregular.When uterine contractions:

As a finger pressing on the fundus of uterus a depression could appear Maternal relative quiet , prolonged process. (painless or can endure )

fetal heart rate changes lately

hertonic uterine inertia and (Uncoordinated contractions)

Often occur together ,elevated resting tone of the uterus

The exciting site of contraction is not from the horn of uterus, and in a particular or multiple site, and with uncoordinated rhythm, polarity inversion.

when uterine contracts the fundus is firm, and the mid or lower uterine segment harder than that.

The uterus can not be completely relaxed, uterine cavity pressure lasting with higher state.

No cervical dilation and No fetal head progressive descent .

Cont: diagnosis:

➖Maternal lasting with abdominal pain.

➖Fetal heart rate changes early

➖Failure to progress

➖Lack of progressive cervical dilatation (primiparas)

➖Prolonged latent phase >16hs

➖Prolonged active phase >8hs ,

cervix dilation <1.2cm/hrs

➖Protracted active phase >2hs