Transcript Dystocia

DYSTOCIA
=
DIFFICULT / ABNORMAL LABOR
Greek
'dys' = 'difficult, painful, disordered, abnormal'
'tokos' meaning 'birth'.
Dr. E Gdansky
Dystocia
Incidence

Overall?
Retrospective/Unreported in normal vaginal
delivery

Primiparous women ~25% have dystocia

Most common indication for primary CS

~50% of CSs are related to dystocia
First Stage of Labor
Duration
Primip. 6-18
Multip. 2-10
Dystocia
Abnormal patterns of labor
Prolonged latent phase
Protracted dilatation
Protracted descent
Protracted 2nd stage
Arrest of dilatation
Arrest of descent
Precipitate labor
Primipara
Multipara
(Normal mean = 6.4 h)
(Normal mean = 4.8 h)
>20 h
>14 h
<1.2 cm/h
<1 cm/h
<1.5 cm/h
<2 cm/h
(Normal mean = 50 min)
(Normal mean = 20 min)
>2 h (+1 h)
>1 h (+1 h)
>2 h
>1 h
>2 h
>1 h
<3 h from onset of
contractions

Powers

Contractions
Expulsive forces


Passage

Maternal pelvis

Passenger

The fetus (Malposition/
Malpresentation)
A combination of these factors
Dystocia
Classification
Dystocia
Causes

Dysfunctional uterine contractions

Hypotonic uterine contracions


Malpresentation (Asynclitism, OP, DTA,
face, braw)
Treatment

Sedation

Hydration

Augmentation of labor
(amniotomy, oxytocin)
Cephalo-pelvic disproportion = CPD

Epidural

Pelvic tumor

Instrumental delivery

Cesarean section
Dystocia
Abnormalities of the passage
Inlet
Mid-pelvis
Outlet
Current Diagnosis & Treatment Obstetrics & Gynecology - 10th Ed. (2007)
Dystocia
Abnormalities of the passage

Bony pelvis
- Gynecoid (50%)
- Android (33% white, 15% black)
- Anthropoid (50% black, 20% white)
-Platypelloid (<3%)
Dystocia
Abnormalities of the passage
Classification:
 Contraction of the pelvic inlet

Contraction of the mid-pelvis and pelvic outlet

General contraction of the pelvis

Pelvic deformities
traumatic fracture,
rickets,
chondrodystrophic
dwarfism,
kyphosis & scoliosis,
exostosis, bone
neoplasia
Dystocia
Abnormalities of the passage

Conjugate
- diagonal (<11.5)
- obstetric (<10 cm)
- true
Transverse diameter (<12 cm)

Interspinous diameter (<8 cm)

Intertuberous diameter (<8 cm)

Pelvimetry
 X-ray
 US
 MRI
 Clinical pelvimetry
Dystocia
Abnormalities of the passage

Soft tissue (uterine or vaginal congenital anomalies,
scarring of the birth canal)

Pelvic mass / neoplasia

Placental location (low implantation / previa)
Dystocia
Obstructed labor

Bandl’s retraction ring & Uterine rupture

Vescicovaginal & rectovaginal fistula

Pelvic floor injury

Increased neonatal morbidity & mortality
Dystocia
Abnormalities of the powers

Normal contractions
- Fundal dominance
- Intensity >24 mmHg (40-60 mmHg)
- Synchronized
- Basal pressure 12-15 mmHg
- Frequency 3-5/10 min
- Duration 60-90 sec
- Rhytm & force are regular

Hypotonic
(causes: excessive sedation, early epidural, over-distended uterus)

Hypertonic
(causes: abruptio, oxytocin, CPD, fetal malpresentation, latent phase of labor)
Dystocia
Abnormalities of the powers


External/ internal Tocodynamometer
Montevideo unit
>200 mmHg is sufficient for normal progress
Dystocia
Abnormalities of the powers


Hypotonic  Amniotomy
Oxytocin augmentation
Hypertonic  Decrease/stop oxytocin
Tocolysis
Sedation in latent phase
Oxytocin (?)
Dystocia
Management of Labor


In any case of CPD (relative or absolute) or failure
treat abnormal progress  CS
Second stage disorder with no evidence of CPD
can, in certain conditions, be treated with:
 Vacuum
- Assisted Delivery
 Forceps Delivery
Dystocia
Precipitate labor




<3 h from onset of contraction
Precipitate dilatation
Primipara
>5 cm/h
Multipara
10 cm/h
Causes:
Extremely strong contractions
low birth canal resistance
Oxytocin (+ associate with placental abruption)
Treatment:
Stop oxytocin
beta mimetics (terbutaline / ritodrine)
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