MANAGEMENT OF LABOR - Al-Kindy College of Medicine
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Transcript MANAGEMENT OF LABOR - Al-Kindy College of Medicine
MANAGEMENT OF
LABOR
Dr Samar Sarsam
• Admission assessment
• *History: History of previous births. The
initial assessment of labor should include a
review of the patient's prenatal care,
including confirmation of the estimated date
of delivery. Focused history taking should be
conducted to include information, such as
the frequency and time of onset of
contractions, the status of the amniotic
membranes (whether spontaneous rupture of
the membranes has occurred, and if so,
whether the amniotic fluid is clear or
meconium stained), the fetal' movements,
and the presence or absence of vaginal
bleeding.
Braxton-Hicks contractions, which are often
irregular and which do not increase in
frequency with increasing intensity, must be
differentiated from true contractions. Braxton
Hicks contractions often resolve with
ambulation or a change in activity. However,
true labor contractions tend to be long and
intense, and they tend to lead to cervical
change. True labor is defined as uterine
contractions leading to cervical changes. If
contractions occur without cervical changes,
it is not true labor. Other causes for the
cramping should be diagnosed. Gestational
age is not a part of the definition of labor.
In addition, Braxton-Hicks contractions occur
occasionally, usually no more than 1-2 per hour,
and they often occur just a few times per day.
Labor contractions are persistent, they may start
as infrequently as every 10-15 minutes, but they
accelerate over time, increasing to 1 every 2-3
minutes.
Patients may also describe what has been called
lightening, ie, physical changes felt because the
fetus' head is advancing into the pelvis. The
mother may feel that her baby has become light
or that it as started to drop and the shape of her
abdomen may change to reflect descent of the
fetus. Her breathing may be relieved because
tension on the diaphragm is reduced, whereas
urination may become frequent because of
added pressure on the bladder.
*General examination:
Physical examination should include
documentation of the patient's height,
weight, vital signs, the fetus'
presentation, and the fetus' wellbeing.
The frequency, duration, and intensity
of uterine contractions should be
assessed.
*Abdominal examination begins with
inspection, and the Leopold maneuvers
described below.
The initial maneuver involves the examiner
placing both of his or her hands on each
upper quadrant of the patient's abdomen and
gently palpating the fundus with the tips of
the fingers to define which fetal pole is
present in the fundus. If it is the fetus' head,
it should feel hard and round. In a breech
presentation, a large, nodular body is felt.
The second maneuver involves palpation in the
paraumbilical regions with both hands by
applying gentle but deep pressure. The purpose
is to differentiate the fetal spine (a hard,
resistant structure) from its limbs (irregular,
mobile small parts) to determinate the fetus'
position.
The third maneuver is suprapubic palpation by
using the thumb and fingers of the dominant
hand. As with the first maneuver, the examiner
ascertains the fetus' presentation and estimates
its station. If the presenting part is not engaged,
a movable body (usually the fetal occiput) can
be felt. This maneuver also allows for an
assessment of the fetal weight and of the
volume of amniotic fluid.
The fourth maneuver involves palpation of
bilateral lower quadrants with the aim of
determining if the presenting part of the fetus is
engaged in the mother's pelvis. The examiner
stands facing the mother's feet. With the tips of
the first 3 fingers of both hands, the examiner
exerts deep pressure in the direction of the axis
of the pelvic inlet. In a cephalic presentation, the
fetus' head is considered engaged if the
examiner's hands diverge as they trace the
fetus' head into the pelvis.
• *Vaginal examination is performed in a sterile
fashion to decrease the risk of infection. Use of
sterile gloves is preferred. If membrane rupture is
suspected, examination with a sterile speculum is
performed to visually confirm pooling of amniotic
fluid in the posterior fornix. The examiner also looks
for fern on a dried sample of the vaginal fluid under a
microscope and checks the pH of the fluid by using
a nitrazine stick or litmus paper, which turns blue if
the amniotic fluid is alkalotic. If frank bleeding is
present, pelvic examination should be deferred until
placenta previa is excluded with ultrasonography.
Furthermore, the pattern of contraction and the
patient's presenting history may provide clues about
placental abruption.
Digital examination of the vagina allows the
clinician to determine the following: (1) the
degree of cervical dilatation, which ranges from
0 cm (closed or fingertip) to 10 cm (complete or
fully dilated), (2) the effacement (assessment of
the cervical length, which is often reported as a
percentage of the normal 3- to 4-cm-long cervix),
(3) the position, ie, anterior or posterior, and (4)
the consistency, ie, soft or firm. Palpation of the
presenting part of the fetus allows the examiner
to establish its station, by quantifying the
distance of the body (-5 to +5 cm) that is
presenting relative to the maternal ischial
spines, where 0 station is in line with the plane
of the maternal ischial spines).
The shape of the mother's pelvis can
also be assessed and classified into 4
broad categories. Gynecoid,
anthropoid, android, and platypelloid.
Although the gynecoid and anthropoid
pelvic shapes are thought to be most
favorable for vaginal delivery, many
women can be classified into 1 or more
pelvic types, and the distinctions can
be arbitrary.
*ADMISSION MANAGEMENT
Identification of labor and differentiation
between true and false labor.
True labor: contractions regular, intervals
shortens increase intensity. Cervix
dilates. Discomfort in the back and
abdomen. Discomfort is not stopped by
sedation.
Fetal assessment in labor (intrapartum
fetal monitoring)
After admission to the labor room, a review of
history risk factors as hypertension, D.M, APH
and others. Examination reveal breech, IUGR,
oligohydramnios, twins, etc. admission CTG is
recommended—if all are reassuring so woman
mobilization for the next few hours is
recommended with intermittent auscultation of
fetal heart using fetal stethoscope this can be
done at intervals of 15-30 minutes. If there is any
abnormality then electronic monitoring is
undertaken.
Information about fetal condition from clinical and electronic
assessment:
*Meconium and liquor volume: color, consistency and
amount of amniotic fluid are used to assess the fetus.
Reduced liquor may predispose to cord occlusion, fetal
hypoxia.
The appearance of meconium staining of the amniotic fluid
is important it could be due to maturity or fetal compromise.
The appearance of meconium is an indication for electronic
fetal monitoring, and the possibility that the fetus may
develops meconium aspiration intrapartum or after delivery
with the onset of breathing. This is why some advise ARM
early in labor. The healthy fetus is able to withstand the
stresses of labor; head compression, umbilical cord
compression and reduced placental blood flow. But on
occasion may become distressed which can be diagnosed
with electronic fetal monitoring and fetal scalp PH
measurement.
*Cardiotocography: The CTG records the
fetal heart rate on a paper strip. This is
carried out either by external abdominal
transducer or fetal scalp attachment through
the vagina.
Uterine contractions are felt with the palm of
the hand and also recorded on the strip by
external or internal monitoring.
The recorded rate may be the mother's heart
rate, this may occur in obese women or with
polyhydramnious or with fetal movements.
Components of CTG:
*Baseline rate: 110-150 bpm.
*Baseline variability: it is variation in
baseline rate over 1 minute normal value
is 10-25 bpm.
*Accelerations (reactivity): increase in fetal heart rate with
an amplitude > 15 bpm for at least 15 seconds, normally 2
accelerations per 15 minutes.
*Decelerations: slowing of fetal heart rate from the baseline,
they are significant when they are 15 bpm less than the
baseline for at least 15 seconds. They are described in
amplitude, duration, shape (v or u shape) and lag time of the
deceleration in relation the peak of contraction. The u
decelerations whose lag time is relatively long (late
deceleration) are significant, while deceleration with
contraction and with short lag time (early deceleration), and
v shaped are less significant.
Continuous fetal heart monitoring is better than intermittent
auscultation. Whenever there is concern about fetal heart
rate, fetal acid base measurement is indicated.
*Fetal scalp blood sampling: hypoxia in the
fetus leads to increase vagal tone which lead
to fetal bradycardia, prolonged hypoxia
results in increase catecholamines from the
adrenal gland it will overcome the vagal
bradycardia so fetal heart rate increase. Fetal
hypoxia leads to fetal academia. Saling in the
1960s described a method by puncturing the
fetal skin to get a blood sample, to measure
the capillary PH. Normal PH level is 7.28-7.34
and a value of 7.2 is the lower limit of fetal
blood PH accepted during labor.
*Fetal pulse oximetry
*Fetal ECG
Management of nonreassuring fetal
heart rate pattern:
-Repositioning of the patient
-Stop oxytocic agents
-Vaginal examination
-Correct maternal hypotension
-Oxygen to the mother
-Fetal heart rate monitoring
-Request for newborn care
-Emergency delivery
Vaginal examination: cervical effacement,
dilatation, position of cervix, station of
presenting part.
Detection of ruptured membranes: leakage of
fluid from the vagina, speculum examination,
or PH of the vagina is 4.5-5.5 while of
amniotic fluid it is 7-7.5or finding
arborization on a slide of vaginal fluid or the
use of nitrazine.
Vital signs and review of pregnancy record
Recording vital signs, pulse and bl. pr hourly
and temperature every 3 hours.
• Preparation of the vulva and
perineum
• Enema: is not routinely used.
• Laboratory: hematocrit or Hb
concentration, blood group, urine
sample for sugar, ketones, proteins
and blood.
The partogram: it is a graphic record of
labor; it allows visual assessment of the
progress of labor so active management can
be instituted if progress is slow.
It has been introduced by Friedman in 1954.
The gradual rise in the latent phase (0-3 cm
dilatation) is followed by the steep slope of
the active phase (4-9 cm) and then short
steep curve to full dilatation. The latent
phase last between 3 and 8 hours, the active
phase last between 2 and 6 hours depending
on parity and other factors.
The rate of cervimetric progress (cervical dilatation),
and the descent of the presenting part represent the
measure of progress of labor. The descent is
observer through the rule of five abdominally and
the level of the presenting part in relation to the
ischial spine vaginally.
Records of uterine contractions and its frequency
and strength.
Ultrasound scan during labor: portable U/S is now
present for bedside diagnosis in the labor room.
Pain relief
The use of pethidin, epidural analgesia and others
will be discussed in other lecture.
Management of normal labor
The first stage of labor
From diagnosis till full dilatation.
The principles of management are:
Care and support
Progress of labor
Monitor fetal well being
Pain relief as the patient wish
Adequate hydration.
Average duration of the first stage of labor in
nulliparous women is about 7 hours and in parous
women is 4 hours, there are marked individual
variations.
The variability is more in the latent phase depending
on the cervical effacement and the Bishop score.
The membranes may be ruptured or not, intermittent
monitoring of fetal heart rate, maternal BP, pulse,
temperature also monitored.
In a normal first stage, encourage mobilization; eat
light diet, vaginal examination every 4 hours.
Progress of labor is plotted on a Partogram, bladder
emptying every few hours.
If abnormal labor; continuous CTG, antacid to the
mother, epidural and urinary catheter.
Maternal vital signs at least every 3 hours, if
membranes are ruptured check the temperature
every hour and start antimicrobial in cases with
prolonged rupture membranes.
Periodic vaginal examination every 2-3 hours to
evaluate the progress of labor.
Liquid oral intake may need intravenous fluid to
administer oxytocin.
Maternal position: allow the women to lie in the
lateral position or any position she is comfortable.
Analgesia: the timing, method of administration, and
size of initial and subsequent doses of
systematically acting analgesic agents are based on
the anticipated interval of time until delivery.
Amniotomy: artificial rupture of membranes may be
indicated.
Urinary bladders function: encourage voiding.
Second stage
With full dilatation of the cervix the woman begins to
bear down and with the descent of the presenting
part she develops the urge to defecate. Uterine
contractions and the expulsive forces may last for 1
and 1/2 minutes and recur after myometrial resting
of no more than a minute.
Duration of the second stage is 50 minutes in
nulliparous and 20 minutes in multiparous, but with
analgesia it may be prolonged to more than 2 hours.
Fetal heart rate may be slowed due to cord and head
compression.
Auscultation in the second stage may be every 15
minutes in low risk group and every 5 minutes in
high risk group.
Maternal tachycardia which is common in the second stage
may be mistaken for fetal heart.
Expulsive forces: in most cases bearing down is reflex and
spontaneous during the second stage, instruction should be
given to the mother regarding the bearing down with
contraction and resting in between, also the position the
recumbent or the squatting position or the dorsal lithotomy
position.
Preparation for labor: the position, cleaning the vulva and the
perineum.
Descent and delivery of the head: it is judged by watching the
perineum, when the head no longer recedes between
contractions (crowning), this indicates that the head has
passed through the pelvic floor and delivery is imminent. The
midwife must control head delivery to prevent sudden birth, so
with crowning the patient should take rapid shallow breaths,
carefully deliver the head by applying pressure through the
perineum onto the forehead. Episiotomy is sometimes needed
to prevent perineal tear it is done with crowning.
Delivery of the shoulders and rest of the body:
after the birth of the fetal head check the cord
round the neck if it is tight around the neck so
clamping is indicated, if there is meconium
nasopharyngeal suction is mandatory to prevent
aspiration. External rotation occur we apply
gentle pull on the head downwards and forwards
until the anterior shoulder appears, the head is
now lifted until the posterior shoulder appears
then deliver the body and legs.
Immediate care to the neonate
After delivery the fetus takes its first breath within
seconds. No need for immediate clamping because
about 80 ml of blood will go to the baby from the
placenta before cord pulsation cease. Keep the head
in dependent position to allow the drainage of
secretions. After clamping the cord, I minute Apgar
score assessed then place the fetus on the mother's
abdomen. Give vitamin K and do general
examination for the baby for any abnormality and a
wrist label attached for identification.
Apgar score: is the clinical evaluation of the
newborn it is usually recoded at I and 5 minutes.
Sign
Heart rate
Respiratory effort
Muscle tone
Reflex irritability
Color
0
1
Absent Below 100 beat
Absent
Weak
Limp Some flexion
2
Over 100 beat
Good strong cry
Active motion, well
flexed extremities
No response Grimace
Cry
Blue, pale Body pink;
Completely pink
extremities blue
Third stage of labor
Delivery of the placenta
SEPARATION OF AMNIOCHORION.
PLACENTAL EXTRUSION.
The retroplacental hematoma either
follows the placenta or is found within the
inverted sac. In this process, known as the
Schultze mechanism of placental
expulsion, blood from the placental site
pours into the inverted sac, not escaping
externally until after extrusion of the
placenta. In the other method of placental
extrusion, known as the Duncan
mechanism, separation of the placenta
occurs first
at the periphery, with the result that blood
collects between the membranes and the
uterine wall and escapes from the vagina
Third stage
It is from delivery of fetus to the expulsion of the
placenta and membranes. It takes 5-10 minutes
normally. If longer than 30 minutes it is prolonged.
Separation of placenta occurs due to reduction of
uterine volume due to contraction and retraction.
Cleavage plane develops and the placenta lies in the
lower segment of the uterus.
Signs of separation are: lengthening of the cord.
Gush of blood
Rising of the uterine fundus, it becomes hard and
globular.
*Traditionally; we wait for signs of separation of the
placenta then expel it by pressing down on the
fundus. This takes 20 minutes and is associated with
5% PPH.
*The modern management of the 3rd stage of labor is active
management and involves a procedure called controlled
cord traction. This technique is as follows:
1-Synthetic oxytocin 10 IU or syntometrine (5 IU oxytocin,
0.5 mg ergometrine) is given by im injection following
delivery of the anterior shoulder. Syntometrine gives a more
sustained contraction but must not be used with
hypertension.
2-after delivery the attendant should place the left hand on
the uterus to identify contraction. During this time observe
any bleeding, clamp the cord after 1-2 minutes after delivery
of the baby, and identify lengthening of the cord.
3-when contraction is felt the left hand
should be put suprapubically to elevate the
fundus with the palm facing the mother, at
the same time the right hand grasping the
cord and exert traction steadily to deliver the
placenta gently. In 2% of cases the placenta
will not be expelled, if no bleeding further
attempt is tried after 10 minutes. If this fails
we need evacuation in the theater. After
completion inspect the placental cotyledons
and examine the vulva for tears or
lacerations.
• Fourth stage of labor
• Examine the placenta and
membranes and for vaginal and
perineal tears. The hour
immediately following delivery is
critical, the uterus is frequently
evaluated and the perineum also
should be inspected.
• Active management of labor
The active management of labor refers to •
active control, rather than passive
observation, over the course of labor by
the obstetrical provider.
There are three essential elements to •
active management: Careful diagnosis of
labor by strict criteria, Constant monitoring
of labor with specific standards for normal
progression, Prompt intervention (eg,
amniotomy, high dose oxytocin) according
to established guidelines if progress is
unsatisfactory
It was introduced during the 1960's to •
shorten the length of labor in nulliparous
women
POPULATION — The active management •
of labor is generally limited to women who
meet the following criteria:
Nulliparous, Term pregnancy, Singleton •
infant in cephalic presentation, No
pregnancy complications, Experiencing
spontaneous onset of labor.