Shoulder dystocia

OUR NIGHTMARE: SHOULDER DYSTOCIA

Dr. Alik Riasadesa Zakaria

M.B.,B.S(Malaya), M.Obsgyn (Malaya)

Department of Obstetrics & Gynaecology

International Islamic University Malaysia

NIGHTMARE

• It is a leading cause of obstetric malpractice claims• Methods of prediction: not sensitive or specific enough• Preventive measures: not effective clinically and economically

DEFINITION AND INCIDENCE

• Definition:– A prolonged head to body delivery time ( i.e. >60 seconds)and/or

the necessitated use of ancillary obstetric manoeuvres

• Incidence:– 0.2-2%

MECHANISM

• Fetopelvic relationships– The antero-posterior diameter of the pelvic is narrower than the

oblique and transverse diameters

MECHANISM

• Fetopelvic relationships– In the term fetus the bisacromial diameter is larger than its

biparietal diameter– In spontaneous labour the head passes through the pelvic inlet

MECHANISM

• Fetopelvic relationships– The posterior shoulder descends via the sacral body

MECHANISM

• Fetopelvic relationships– Followed by anterior shoulder which will be accommodated by the

obturator foramen

MECHANISM

• Fetopelvic relationships– Usually the posterior shoulder will descend below the sacral

promontory and it is the anterior shoulder that becomes impacted behind the pubic symphysis: unilateral shoulder dystocia

– On very rare occasions the posterior shoulder fails to descend below the sacral promontory, so that both the anterior and posterior shoulders are arrested above the pelvic brim: bilateral shoulder dystocia

MECHANISM

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PREDISPOSING FACTORS

• There are number of predisposing factors, but there are not sensitive or specific

1. Antepartum

2. Intrapartum

PREDISPOSING FACTORS: ANTEPARTUM

1. MACROSOMIA• Is the most important risk factor• The risk of shoulder dystocia increases with rising birth weight

2. INFANTS OF DIABETIC MOTHERS• Hyperglycaemia and hyperinsulinaemia cause excessive growth

of shoulder girth • Therefore they are at a greater risk of shoulder dystocia in

comparison to nondiabetic infants of the same weight


3. POST DATE PREGNANCY• In the later weeks of pregnancy the biparietal diameter growth

slows but the fetal chest and shoulders continue to grow steadily• This causes shoulder to be bigger than the head, thus increases

the risk of shoulder dystocia

4. MATERNAL OBESITY• It has been shown in number of studies to be associated with

increased incidence of shoulder dystocia• There is 8-fold increased in the risk of shoulder dystocia in

women weighing less than 90kg compare to those weighing more than 113kg


5. EXCESSIVE WEIGHT GAIN• Has also been linked to macrosomia

PREDISPOSING FACTORS:INTRAPARTUM

• MOST CASES OF SHOULDER DYSTOCIA HAVE A NORMAL PROGRESSION IN LABOUR

• HOWEVER , THERE ARE CERTAIN PATTERNS OF LABOUR DO INCREASE THE LIKELIHOOD OF SHOULDER DYSTOCIA:

1. Prolonged active phase of labour

2. Poor descent in the second stage of labour

3. Assisted mid-pelvis delivery



PREVENTION

• PREVENTION IS MAINLY INVOLVED PROPER MANAGEMENT OF RISK FACTORS

PREVENTION:MANAGEMENT OF ANTEPARTUM RISK FACTORS

1. OBESITY• BMI determination offers more precise quantification of obesity• Advise on adequate but not excessive prenatal weight gain and

recommended weight gain based on BMI should be documented

2. EXCESSIVE WEIGHT GAIN• Women with excessive weight gain should be referred to dietician

and should received counselling about activity• They may benefit from increased support during prenatal visits at

more frequent interval


3. DIABETES• Women should be referred to dietician for proper dietary advice• Insulin therapy should be started early if the blood sugars are

poor controlled with diet modification• Diet and/or insulin therapy reduces both macrosomia and the

incidence of shoulder dystocia


4. POST DATE PREGNANCY• Some cilinicians plans an early induction of labour to prevent

macrosomia and thus avoiding shoulder dystocia• But does it works? • Study shows that the above approached does reduced the

incidence of macrosomia but does not reduced the incidence of shoulder dystocia

• ACOG recommended that there is no indication for early induction of labour if the ultrasound estimation of fetal weight ranges from 4000-4500g at term


5. MACROSOMIA• Guidelines published by ACOG do not support elective

Caesarean for all women suspected macrosomia• But in patient with a history of shoulder dystocia, maternal

glucose intolerence and severe prior neonatal injury, risks and benefits of Caesarean delivery should be discussed with the patient

• Planned Caesarean delivery to prevent shoulder dystocia may be considered for suspected fetal macrosomia with estimated fetal weight exceedinf 5000g in women without diabetes and 4500g in women with diabetes

MANAGEMENT

• DIAGNOSIS:– When the head delivers, either spontaneously or assisted, but

does not undergo external rotation and recoils tightly back against the perineum; often called the “turtle sign”

MANAGEMENT



MANAGEMENT

• STOPSTOP THE TRACTION

• RED ALERTRED ALERT; DO NOT PANIC AND CALL FOR HELP

• GENEROUS EPISIOTOMY...PLEASE!!!GENEROUS EPISIOTOMY...PLEASE!!!

MANAGEMENT

1.1. MC ROBERTS’ MANOEUVRE; MC ROBERTS’ MANOEUVRE; APPLY FIRM FLEXION AND ABDUCTION OF THE MATERNAL THIGHS TO INCREASED THE PELVIC INLET

• APPLY SUPRAPUBICAPPLY SUPRAPUBIC (NOT FUNDAL) TO THE ANTERIOR SHOULDER TO TO ROTATE TO THE OBLIQUE DIAMETER AND UNDER THE SYMPHYSIS PUBIS

MANAGEMENT



MANAGEMENT



MANAGEMENT



MANAGEMENT

QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.

MANAGEMENT

• Mc Robert manoeuvre alone freed the shoulder in 41% of cases

• Mc Robert manoeuvre combined with suprapubic pressure freed another 40%

• Thank God!!! Thank God!!! 80% of the time we can stop here...

• But if we have to go on......what is next......But if we have to go on......what is next......

MANAGEMENT

22. ROTATE THE FETAL SHOULDERS TO THE OBLIQUE ROTATE THE FETAL SHOULDERS TO THE OBLIQUE DIAMETER OF THE PELVIC BRIM;DIAMETER OF THE PELVIC BRIM; OBLIQUE DIAMETER OF THE PELVIS IS WIDER!!!

• Push the infant’s posterior shoulder off the midline to the oblique diameter

• If this FAILS@*%##@FAILS@*%##@

MANAGEMENT

• Am I SCREWED YET??? SCREWED YET???

3.3. I GUESS NOT..WOODS’ CORKSCREW MANOEUVRE!!!I GUESS NOT..WOODS’ CORKSCREW MANOEUVRE!!!

• Continue rotating the infant’s posterior shoulder; (R) hand if infant’s back was on the mother’s (R), and exerting the pressure to rotate the fetus 1800

MANAGEMENT



MANAGEMENT

• In doing so;– The posterior shoulder, which is below the pelvic brim, remains at

that level and is rotated to become the anterior shoulder below the sub-pubic arch, whence it can be delivered

– The former anterior shoulder, which was above the pelvic brim, has been corkscrewed below the level of the pelvic brim and become the posterior shoulder

• What if this still failed to deliver the shoulder....What if this still failed to deliver the shoulder....

MANAGEMENT

4.4. DELIVER THE POSTERIOR SHOULDER.....DELIVER THE POSTERIOR SHOULDER.....– Pass the hand deep into the vagina and sacral hollow, identify

the fetal humerus and follow it to the elbow

MANAGEMENT

• DELIVER THE POSTERIOR SHOULDER.....

– The elbow is flexed and the forearm grasped and swept across the fetal chest

MANAGEMENT

• DELIVER THE POSTERIOR SHOULDER.....– After delivery of the posterior arm, the anterior shoulder

should be able to be delivered

– If not, support the fetal head and trunk and rotate though 180o which served to bring the anterior shoulder below the pelvic brim into the sacrum where it will be accessible

MANAGEMENT

• HOW DOES DELIVERY OF THE POSTERIOR SHOULDER HELP ??....

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QuickTime™ and aTIFF (LZW) decompressor


MANAGEMENT

• DELIVER THE POSTERIOR SHOULDER.....

• BUT IT DOESN’T HELP AT ALL..!!!!! WHAT TO DO NEXT???BUT IT DOESN’T HELP AT ALL..!!!!! WHAT TO DO NEXT???

MANAGEMENT

5.5. ALL-FOURS MANOEUVRE???ALL-FOURS MANOEUVRE???



MANAGEMENT

• ALL-FOURS MANOEUVRE...– Basis: The flexibility of the sacro-iliac joint which allows 1-2cm

increased in the antero-posterior diameter of the pelvic inlet

– In lithotomy: the posterior mobility of the sacrum is limited

– The gravity: Helps push the posterior forward and over the sacral promontory

MANAGEMENT

MANAGEMENT

• STILL SHOULDER NOT DELIVERED....STILL SHOULDER NOT DELIVERED....

• ZAVANELLI MANOEUVRE:– Grasps the fetal head, flexed it and pushed it into the vagina– Arrange for Caesarean delivery

• SYMPHYSIOTOMY

MANAGEMENT

• DOCUMENTATION:DOCUMENTATION:

– It is important that the delivery and manoeuvres required to deliver the baby carefully recorded by all present

– This will help planning future delivery and provide sound medico legal defence

– Umbilical cord blood gas analysis should be obtained– Damage suffered by the infant should be recorded as it reflects

the severity of the shoulder dystocia

COMPLICATIONS

• FETAL:1. Fracture of the clavicle: 15%

2. Brachial plexus injury; – 5-15%

– The vast majority are of the Erb-Duchenne type (C5&C6 nerve roots)

– The majority of cases of brachial plexus injury resolve with time– Less than 10% long term disability

COMPLICATIONS

• FETAL:

3. Fracture of the humerus: 1%

4. Hypoxic fetal brain damage

COMPLICATIONS

• MATERNAL:1. Lower genital tract lacerations;

– Due to the generous episiotomy &– Distension of the vagina by the manoeuvre

2. Post-partum haemorrhage:– Episiotomy and lacerations– Uterine atony– Rarely uterine rupture

3. In rare cases of Zavanelli manoeuvre:– Haemorrhage– Blood transfusion– Hysterectomy





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Shoulder dystocia