Transcript CONJOINED TWINS

SEPARATING CONJOINED
TWINS
David Tuggle MD
History
 Pliny
70 AD
 maids of Biddenden, England
 Mary and Eliza Chalkhurst
 died age 34, 6 hours apart
 likely parapagus twins
History
Konig first recorded separation
 Ligated the liver bridge
 1689 !
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History
New world
 Johanna and Melchioraa
 July 18, 1533
 One soul or two?
 Joined at the liver, so they were thought to
have two souls
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The Bunkers
Eng and Chang bunker
 born in Thailand (then called Siam)
 Band of tissue 4.5 x 3.5 x 7.5 inches
 Liver and peritoneum
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Anatomy and Life
Originally they faced each other
 Over time they stretched their connection
 PT Barnum
 Made a fortune
 Retired to Mount Airy, NC age 42
 Gentlemen of the south
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Bunker History
Wives quarreled
 19 to 24 children between them
 Fixed schedule of "visitation"
 Civil war destroyed their fortunes
 Back to show business until 1872
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Bunker history
Chang had a stroke and they retired again
 Chang got pneumonia and died in the
night
 Eng lived 2.5 hours longer then also died
 Autopsy showed a thin liver bridge, skin,
and peritoneum
 No clear reason why Eng died, fear?
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Recent History
1988 O Neill
 13 twin separations at one institution
 Prior to that 100 successful separations
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China vs OKC
7 cases in Shanghai from 1980 to 2005
 Shanghai Population- 20,000,000
 2 cases in Oklahoma City from 1986 to
2009
 OKC Population- 2,000,000 !!!
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Frequency
twins occur in 80-90 pregnancies
 2/3 of twins are dizygotic, 1/3 monozygotic
 1 in 40 monozygotic twinnings are
incomplete
 about 1 in 50,000 births, stillborn rate is
60%
 live born conjoined twins about 1 in
200,000
 females 3:1
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Twinning
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All monozygotic twinning occurs in the first week
Incomplete division of the embryonic disc occurs
in 2nd wk
This early occurrence leads to wide variety of
twinning and uniqueness
Conjoined twins
Parasitic twin
Atypical conjoined twin
Major early defects up to 20%
Types of Conjoined twins
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cephalopagus
thoracopagus
omphalopagus
ischiopagus
parapagus
craniopagus
rachipagus
pygopagus
Cephalopagus
Top of the head to umbilicus
 0.5% of CJT
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Thoracopagus
Chest wall to abdomen
 Most often share a heart
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Omphalopagus
Omphalopagus twins may share a liver,
gastrointestinal or genitourinary functions,
but rarely share a heart. Some Thorax
Ischiopagus
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twins are joined at the pelvis. Many
Ischiopagus share lower gastrointestinal
tract, as well as the genital and urinary
tract organs
Ischipagus tripus
Parapagus
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Fused side-by-side with a shared pelvis. Twins that
are dithoracic parapagus are fused at the abdomen
and pelvis, but not the thorax. Twins that are
diprosopic parapagus have one trunk and one head
with two faces. Twins that are dicephalic parapagus
have one trunk and two heads, and two (dibrachius),
three (tribrachius), or four (tetrabrachius) arms
Craniopagus
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Conjoined twins connected only at the
head. They share bones of the skull and
occasionally brain surface, separate
trunks, four arms, four legs. About 2% of
conjoined twins are craniopagus.
Rachipagus
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Joined back to back at any point above the
lumbar spine
Pygopagus
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connected at the rump. Pygopagus twins,
about 19%, have separate hearts but may
share a spinal cord. There is one anus,
two rectums, four arms and four legs
Work Up
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identified prenatally
fetal echocardiogram
10-20% associated congenital anomalies
evaluate skin surface
tissue expanders an option
CT, heart echo, hida scan, barium ugi if needed
angiography for evidence of shared circulation
Things to think about
treatment options
 stable or unstable
 75% are thoracopagus or omphalopagus
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Immediately after birth
Airway management
 Resuscitation
 ventilation
 IV access
 Separate teams even at birth
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Immediate treatment
May need emergency separation
 May need Ex Utero intrapartum (EXIT)
delivery
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Work up post delivery
One heart or two
 Can the two hearts be separated?
 One QRS or two?
 Echocardiograms
 Cardiac catheterization
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Pulmonary- thoracopagus
Shunts
 Chest deformity
 Scoliosis/posture
 Shared thoracic cavity
 Pulmonary hypertension
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Abdominal Workup
Liver
 Biliary
 Gastrointestinal
 Genitourinary
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Ethics
Should they be separated?
 Quality of life
 Will one be sacrificed to save the other?
 Societal values, legal issues, institution
 Wishes of the parents
 Control the media
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Timing
Timing is not set in stone
 Immediate to 12 months
 Greater than 12 months= separation
anxiety
 Differential growth
 Cross over circulation
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Anesthesia
Complex
 Cross circulation
 IV access for each
 Anatomy governs the monitoring, access,
and anesthetic deliver
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Outcomes
Craniopagus and thoracopagus worst
 Ischiopagus and pygopagus have best
results
 Long term follow up crucial
 Often a need for follow up surgery
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