Pediatric Surgery Part II: No poop, no peace Sumit De, M.D. PGY-2 Department of Surgery Drexel University College of Medicine Basic Science March 21, 2006

1
Pediatric SurgeryPart II No poop, no
peaceSumit De, M.D.PGY-2Department of
SurgeryDrexel University College of
MedicineBasic ScienceMarch 21, 2006
2
Hypertrophic Pyloric Stenosis

• Incidence 13000 to 4000 live births, most
  commonly in first 2-8 weeks
• Circular muscle of the pylorus results in
  constriction and obstruction leading to
  nonbilious, projectile emesis
• As a result, patient develops hyperchloremic,
  metabolic alkalosis, and subsequent dehydration

3
Hypertrophic Pyloric Stenosis

• Physical exam can be confirmatory
• Palpation of the pyloric tumor, aka the olive, in
  the epigastrium or RUQ is pathognomonic
• ? No other tests are necessary
• Sensitivity 72-74, Positive Predictive value
  98-99.3, Specificity 97
• No Olive? UGI or U/S

4
Treatment of Pyloric Stenosis
Pyloromyotomy

• Abnormal pyloric musculature

Normal underlying mucosa
Incision options RUQ Periumbilical Laparoscopic
5
(No Transcript)
6
Duodenal Atresia

• Occurs due to failure of the vacuolization of the
  duodenum from its solid cord stage
• Range of anatomic variants include duodenal
  stenosis, mucosal webbing with intact muscular
  wall (windstock deformity), two ends separated
  by fibrous cord, or complete separation with a
  gap within the dudodenum
• Associations prematurity, Down syndrome,
  maternal polyhydramnios, malrotation, annular
  pancreas, biliary atresia

7
Duodenal Atresia

• Double-bubble sign is pathognomonic for duodenal
  atresia
• If distal air is present, UGI should be performed
  to rule out malrotation
• Can do UGI to diagnose as well

8
Duodenal Atresia Repair

• Proximal transverse to distal longitudinal
  duodenoduodenostomy
• Alternatively, side-to-side duodenoduodenostomy
  is possible

9
Jejunoileal Atresia
Jejunoileal Atresia
In type I atresias, the mucosa and submucosa form
a web or intraluminal diaphragm, resulting in
obstruction. A windsock effect may be evident
secondary to an increase in intraluminal pressure
in the proximal bowel causing a prolapse of a
portion of the web into the distal part of the
bowel. A mesentery defect is not present, and the
bowel length is not shortened.
10
Jejunoileal Atresia
Type II The mesentery is intact in type II
atresias however, the bowel is not joined. The
dilated proximal portion has a bulbous blind end
connected by a short fibrous cord to the blind
end of the distal flattened bowel. The overall
length of the small bowel is not usually
shortened.
11
Jejunoileal Atresia
Type IIIa The defect in type IIIa is similar to
that in type II in that both types have blind
proximal and distal ends however, in type IIIa,
complete disconnection exists. In addition, a
V-shaped mesenteric defect is present. The
proximal blind end is usually markedly dilated
and not peristaltic. The compromised bowel
undergoes intrauterine absorption, and as a
result, the bowel in this category is variably
shortened.
12
Jejunoileal Atresia
Type IIIb In addition to a large defect of the
mesentery, the bowel is significantly shortened.
This lesion is also known as Christmas tree
deformity because the bowel has the appearance of
the tinsel coil wrapped around a single perfusing
vessel, or Christmas tree. It has also been
called an apple peel deformity. The distal ileum
receives its blood supply from a single ileocolic
or right colic artery because the better part of
the superior mesenteric artery is absent.
Prematurity, malrotation, and subsequent short
bowel syndrome have been linked to this
deformity, with increased morbidity and mortality
rates.
13
Jejunoileal Atresia
Type IV Type IV involves multiple small-bowel
atresias of any combination of types I to III.
This defect often takes on the appearance of a
string of sausages because of the multiple
lesions. The cause is unknown, and theories range
from multiple ischemic infarcts to an early
embryologic defect of the GI tract to an
inflammatory process occurring in utero.
14
Anomalies of Intestinal Rotation/Fixation

• True incidence of malrotation is hard to
  determine, though a generally accepted estimate
  is 1 in 6000 births
• Suspected malrotation warrants plain abdominal
  films and a UGI contrast series
• Midgut volvulus is a true surgical emergency
• Sudden appearance of bilious emesis in a newborn
• Patients can have chronic abdominal pain or
  intermittent non-bilious episodes of emesis,
  early satiety weight loss, FTT, or
  malabsorption/diarrhea

15
Embryologic Rotation of the Gut
Stage of Rotation Description
I Extrusion of the midgut into the extraembryonic cavity, a 90 counterclockwise rotation, and midgut returns to abdominal cavity
II Counterclockwise rotation within the abdominal cavity completing a 270 rotation duodenal c loop behind SMA
III Fusion and anchoring of the mesentery, cecum descends
16
Stringer Classificationof Midgut Malrotation
Type Description
Ia Proximal bowel on the right, cecum on the left
IIa Nonrotation of the duodeum
IIb Duodenum and colon show reversed rotation
IIc Reversed rotation of the duodenum only
IIIa Duodenum and colon fail to rotate
IIIb Incomplete fixation of the hepatic flexure
IIIc Incomplete attachment of the cecum
IIId Internal herniation near the ligament of Treitz
17
Ladds Procedure

• Counterclockwise reduction of midgut volvulus
• Splitting of Ladds bands
• Division of peritoneal attachments to the cecum,
  ascending colon
• Appendectomy

18
SMV Inversion Sign
Arrowhead SMV inversion Open arrow R-sided
duodenojejunal junction
19
Necrotizing Enterocolitis

• Most common GI emergency in the newborn period
• Prematurity is the single most important factor
• Other contributors ischemia, bacteria,
  cytokines, enteral feedings
• Approximately 80 of cases occur within first
  month of life
• Clinical signs include irritability, temperature
  instability, poor feeding, apnea, bradycardia
• Single most common cause of short gut syndrome in
  kids

20
Necrotizing Enterocolitis
Necrotizing Enterocolitis

• Pneumotosis intestinalis
• Trigger words ground glass, train tracks
• Most common site for involvement is the splenic
  flexure

21
Necrotizing Enterocolitis

• Medical management of 7-10 days is successful 50
  of the time
• Absolute indication for surgery is perforation
  with free air IDd
• Relative indications for surgery clinical
  deterioration, abdominal wall cellulitis,
  worsening acidosis, falling WBC/Plts, palpable
  abdominal mass, fixed bowel loop
• Basic management resect all nonviable segments
  and create a stoma
• Second looks may be performed in 24 hours for
  ischemia
• Bedside peritoneal drainage performed on selected
  patients
• Overall mortality 10-50

22
Meconium Syndromes

• Associated with Cystic Fibrosis
• CFTR gene carried by 3.3 of Caucasion population
  in the U.S.
• Meconium plug syndrome is associated with
  Hirschsprungs, maternal diabetes, hypothyroidism
  as well as CF
• Therapeutic procedure of choice water-soluble
  contrast enema, successful 75 of the time

23
Simple Meconium Ileus

• Affects 15 of all CF patients worldwide
• In the U.S., if you have a meconium
• ileus, you have CF until proven otherwise
• Affects 15 of all CF patients worldwide

• X-rays show dilated, gas-filled loops of small
  bowel, no air-fluid levels, ground glass or
  soap bubble appearance on right side
• Surgery for enema failure enterotomy into distal
  ileum, irrigate with saline or 4
  N-acetylcysteine

24
Intussusception

• Telescoping of one portion of intestine into
  another
• Most common cause of intestinal obstruction in
  childhood
• Most often, cause is not known, located at
  ileocecal junction, and there is no obvious lead
  point (present in 12 of cases)
• Lymphoid swelling from recent infection is one
  theory
• Most common lead point is Meckels diverticulum
  others include polyps, appendix, intestinal
  neoplasm, submucosal hemorrhage, foreign body,
  ectopic pancreatic or gastric tissue
• Abdominal mass may be palpated, child will writhe
  in pain, currant jelly stools due to onset of
  bowel ischemia
• Seen on x-ray half the time

25
Intussusception

• Hydrostatic enema 80 (barium, saline)
• Air enema
• Recurrence in first 24 hours 11, re-enema
• Third recurrence operation
• ? peritonitis clinical sx of necrotic bowel
  also indications
• Squeeze mass retrograde, distal to proximal
• Recurrence after surgery is quite low
• Resect when intussusception cannot be reduced,
  viability of bowel is called into quesiton, lead
  point is identified
• ?ileocolectomy with primary reanastamosis is
  standard

26
Hirschsprungs Disease

• 15000 live births
• Absent ganglion cells in myenteric (Auerbachs)
  and submucosal (Meissners) plexus
• Muscle spasm of distal colon and internal anal
  sphincter resulting in functional obstruction
• Aganglionosis incidence 100 distal rectum, 75
  rectosigmoid, splenic flexure or transverse 17,
  entire colon with possible small bowel
  involvement 8
• Most are symptomatic within first 24 hours of
  life progressive abdominal distension, bilious
  emesis, no meconium passage
• Enterocolitis can cause diarrhea. Most common
  cause of death in patients with uncorrected
  Hirschsprungs.
• Older children present with poor feeding hx,
  chronic abdominal distention, significant
  constipation
• Biopsy in older kids is common

27
Hirschsprungs Disease

• Avoid enemas and DRE prior to barium enema
• In normal barium enema, rectum is wider than the
  sigmoid colon
• Failure to expel contrast within 24 hours is also
  indicative
• Anal Manometry
• Gold standard rectal biopsy
• ? in newborns, must go 2 cm above dentate line
  to avoid getting transition zone
• ? in older kids, get a full thickness biopsy

28

Hirschsprungs Disease
The Swenson procedure leaves a small portion of
the diseased bowel. The Soave procedure leaves
the outer wall of the colon unaltered. Meanwhile,
the Duhamel procedure uses a surgical stapler to
connect the good and bad bowel. The front of the
bowel will end up with no cells, but the back
will be healthy.
29
Imperforate Anus

• Incidence 1 in 4000-5000 live births, more
  common in boys
• Anatomic classification based on level of blind
  rectal pouch
• Coexistant congenital anomalies must always be
  considered
• Genitourinary abnormalities other than
  rectourinary fistula occur in 26-59 of patients
• Newborn with low lesion non-colostomy
  single-stage repair
• Infants with high lesion three-stage repair with
  colostomy

30
Imperforate Anus
Female Anorectal Malformations
Male Anorectal Malformations
Female Male
High Anorectal agenesis with or without rectovaginal fistula rectal atresia Anorectal agenesis with or without rectoprostatic urethral fistula rectal atresia
Intermediate Anorectal agenesis with or without rectovaginal fistula anal agenesis Anorectal agenesis with or without rectobulbar urethral fistula anal agenesis
Low Anovestibular or anocutaneous fistula, anal stenosis anocutaneous fistula, anal stenosis
31
Imperforate Anus

• Cloaca/rectovesical fistula perineal fistula
• 90 10 genitourinary abnormality
• Genitourinary abnormalities other than
  rectourinary fistula occur in 26-59 of patients
• 75 of all patients have voluntary bowel
  movements
• Constipation is the most common sequelae

32
Review Question 1

• Which one of the following would NOT be true for
  infants?
• Umbilical artery embolization is associated with
  isolated intestinal perforation
• Primary peritoneal drainage is definitive therapy
  for those with intestinal perforation associated
  with necrotizing entercolitis (NEC)
• Survival is equivalent for those with perforated
  NEC treated initially with laparotomy or primary
  peritoneal drainage
• Primary peritoneal drainage is appropriate for
  those with intestinal perforation who are too
  unstable for laparotomy
• Medical treatment for patent ductus arteriosus is
  associated with isolated intestinal perforation

33
Review Question 1

• Which one of the following would NOT be true for
  infants?
• Umbilical artery embolization is associated with
  isolated intestinal perforation
• Primary peritoneal drainage is definitive therapy
  for those with intestinal perforation associated
  with necrotizing entercolitis (NEC)
• Survival is equivalent for those with perforated
  NEC treated initially with laparotomy or primary
  peritoneal drainage
• Primary peritoneal drainage is appropriate for
  those with intestinal perforation who are too
  unstable for laparotomy
• Medical treatment for patent ductus arteriosus is
  associated with isolated intestinal perforation

34
Review Question 2

• One day after pyloromyotomy for hypertrophic
  pyloric stenosis, a 4-week-old infant continues
  to vomit during and after feedings. The best
  management would be
• Observation
• Endoscopy and pyloric dilatation
• An upper gastrointestinal series
• Operative extension of the myotomy
• Insertion of a duodenal feeding tube

35
Review Question 2

• One day after pyloromyotomy for hypertrophic
  pyloric stenosis, a 4-week-old infant continues
  to vomit during and after feedings. The best
  management would be
• Observation
• Endoscopy and pyloric dilatation
• An upper gastrointestinal series
• Operative extension of the myotomy
• Insertion of a duodenal feeding tube

36
Review Question 3

• A 2-month old male infant has a history of
  constipation. He was delivered at home by a
  midwife and did not pass meconium until he was 36
  hours old. He is failing to thrive and has
  abdominal distension. A rectal biopsy is
  performed simultaneous with this contrast colon
  study.
• The histology of the rectal biopsy will show
• Absence of nerve fibers
• Normal number of ganglion cells in Meissners
  plexus
• Decreased acetylcholinesterase staining
• No ganglion cells
• Normal number of ganglion cells in Auerbachs
  plexus

37
Review Question 3

• A 2-month old male infant has a history of
  constipation. He was delivered at home by a
  midwife and did not pass meconium until he was 36
  hours old. He is failing to thrive and has
  abdominal distension. A rectal biopsy is
  performed simultaneous with this contrast colon
  study.
• The histology of the rectal biopsy will show
• Absence of nerve fibers
• Normal number of ganglion cells in Meissners
  plexus
• Decreased acetylcholinesterase staining
• No ganglion cells
• Normal number of ganglion cells in Auerbachs
  plexus

38
Special thanks toDr. Douglas Katz whose image
library I pillaged.