Common Pediatric Surgeries -GI

Question 1

What is Gastroschisis?

Answer 1

-Defect of the anterior abdominal wall of the right of the umbilical cord

-no sac- bowel is exposed to the intrauterine environment

-bowel is matted, thickened and covered w an inflammatory coating

-malabsorption issues

-results in peritonitis, extracellular fluid loss, significant heat loss

-fascial defect in 2-5 cm

-usually involves only large and small intestines

Question 2

What is Gastroschisis a result of?

Answer 2

A vascular event resulting from an abnormality of a right omphalomesenteric artery or right umbilical vein

results in ischemia to the right paraumbilical area and dysplastic abdominal wall growth

Weakened area ruptures as abdominal organs grow

Question 3

What are the risk factors for gastroschisis?

Answer 3

young maternal age, exposure to tobacco and alcohol during development

Question 4

What are the risk factors for gastroschisis?

Answer 4

young maternal age, exposure to tobacco and alcohol during development

Question 5

How is gastroschisis diagnosed?

Answer 5

before birth via ultrasound- associated w increased maternal serum alpha fetoprotein

Question 6

What is Omphalocele?

Answer 6

Central defect of umbilical ring/base of umbilical cord

Abdominal contents are within a sac

umbillical cord embedded in sac

fascical defect >4cm

Sac contains stomach, large and small intestine, liver (30-50%)

(less than 4cm- considered umbilical hernia)

Question 7

What is the embryology or omphalocele?

Answer 7

week 7-12: midgut herniated into umbilical cord

Week 12: abdominal cavity is large enough, gut re-enters abdomen.

• failure of gut to return to abdominal cavity

Question 8

What anomalies is gastroschisis associated with?

Answer 8

• isolated lesion

Question 9

What associated anomalies is omphalocele with?

Answer 9

50-70% incidence of other anomalies
20-30% chromosomal abnormalities
Beckwith- Wiedemann syndrome, Reiger syndrome, Prune belly syndrome
Trisomy 13, 15, 18, 21
Cardiac 20%

Question 10

What symptoms/anomalies does Beckwith-Wiedemann Syndrome come with?

Answer 10

-omphalocele
-visceromegaly
-macroglossia
-mild microcephaly
-hypogycemia

Question 11

What symptoms/anomalies does Beckwith-Wiedemann Syndrome come with?

Answer 11

-omphalocele
-visceromegaly
-macroglossia
-mild microcephaly
-hypogycemia

Question 12

What is the surgical management for these pts?

Answer 12

-replacing the viscera and repairing the defect
-Primary vs. Staged repair w silo/mesh chimney
-staged- organs gradually returned to the abdominal cavity over 3-14 days

Question 13

What are the factors that determine surgical management?

Answer 13

• size of the defect
  -development of the abdominal wall
  -presence of anomalies

Question 14

What are the negative effects of tight abdominal closure?

Answer 14

-impairs diaphragmatic excursion- inadequate ventilation, increased airway pressure

• impedes venous return- profound HoTN

-aortocaval compression -bowel ischemia, decreased CO, renal and hepatic dysfunction

Question 15

What are the negative effects of tight abdominal closure?

Answer 15

-impairs diaphragmatic excursion- inadequate ventilation, increased airway pressure

• impedes venous return- profound HoTN

-aortocaval compression -bowel ischemia, decreased CO, renal and hepatic dysfunction

Question 16

What is considered unsafe for primary closure?

Answer 16

Intragastric pressure >20 mmHg
Change in CVP > 4mmHg above baseline
ETCO2 >50 mmHg
Peak inspiratory pressure > 35 cm h2o

Question 17

What is considered unsafe for primary closure?

Answer 17

Intragastric pressure >20 mmHg
Change in CVP > 4mmHg above baseline
ETCO2 >50 mmHg
Peak inspiratory pressure > 35 cm h2o

Question 18

What is the reasoning for massive fluid losses?

Answer 18

Peritonitis, edema, ischemia, protein loss, third space loss, which results in dehydration metabolic acidosis, hypovolemic shock

Question 19

How should you fluid resuscitate?

Answer 19

Maintenance fluid: D5 or D10 in 0.2NS

replacement fluid: isotonic at 2-4 times maintenance rate

NS or LR as replacement (8-15 ml/kg/hr)

Question 20

What should UOP be maintained at?

Answer 20

1-2ml/kg/hr

Question 21

How should you maintain normothermia

Answer 21

prevent heat loss from exposed viscera

• cover abdominal contents w warm, saline-soaked gauze
  -cover w plastic bowel bag

Question 22

Where should the two pulse ox monitors be placed?

Answer 22

pre-ductal (right arm)

Post ductal (left foot)

Question 23

What gas should be avoided?

Answer 23

Nitrous oxide - bowel distention

Question 24

what should spo2 and pao2 be maintained at?

Answer 24

spo2: 95-97%

pao2: 50-70mmhg

Question 25

What should be done to prevent hypothermia?

Answer 25

room temp 80 degrees bair hugger fluid warmer plastic wrap for extremities, head, and leave hat on

Question 26

What should be done to prevent hypothermia?

Answer 26

room temp 80 degrees bair hugger fluid warmer plastic wrap for extremities, head, and leave hat on

Question 27

What factors will determine extubation?

Answer 27

size of pt/prematurity associated anomalies size defect type of repair intraop events hemodynamic status

Question 28

What factors will determine extubation?

Answer 28

size of pt/prematurity associated anomalies size defect type of repair intraop events hemodynamic status

Question 29

What is the post-op management for these cases?

Answer 29

-mechanical ventilation for 24-48 hrs -fluid requirements closely monitored -circulatory compromise- cyanotic lower limbs, bowel ischemia -prolonged post-op ileus- TPN required for days to weeks -prevent infection

Question 29

What is the post-op management for these cases?

Answer 29

-mechanical ventilation for 24-48 hrs -fluid requirements closely monitored -circulatory compromise- cyanotic lower limbs, bowel ischemia -prolonged post-op ileus- TPN required for days to weeks -prevent infection

Question 30

What are some post-op complications?

Answer 30

-pneumonia -necrotizing enterocolitis (NEC) -renal insufficiency -abdominal wall breakdown -GERD

Question 31

What is a congenital diaphragmatic hernia (CDH)?

Answer 31

-defect in the diaphragm that allows herniation of abdominal organs into the thoracic cavity

Question 32

What are the associated anomalies of CDH?

Answer 32

prenatal hx of polyhydramnios -malrotation of the gut -CV -CNS, GI, GU

Question 33

What are the associated anomalies of CDH?

Answer 33

prenatal hx of polyhydramnios -malrotation of the gut -CV -CNS, GI, GU

Question 34

What are the classifications of CDH?

Answer 34

Posterolateral (80-90%) left (75%) paraesophageal 15-20% anteromedial 2%

Question 35

What are the complications of CDH?

Answer 35

-bilateral lung hypoplasia -pulm HTN and arteriolar reactivity -Left ventricular dysfunction

Question 36

What is the pathophysiology of CDH?

Answer 36

Abdominal viscera occupies the left thoracic cavity and interferes w the development of the lung resulting in pulm hypoplasia Herniation of abdominal contents shifts mediastinum to the right resulting in compression and hypoplasia of the contralateral lung Structural abnormalities of pulm vasculature resulting in chronic lung disease -Small number of airways -Simple arterial branching pattern -Increased smooth muscle mass in resistance vessels -Left ventricular abnormalities

Question 37

What is the pathophysiology of CDH?

Answer 37

Abdominal viscera occupies the left thoracic cavity and interferes w the development of the lung resulting in pulm hypoplasia Herniation of abdominal contents shifts mediastinum to the right resulting in compression and hypoplasia of the contralateral lung Structural abnormalities of pulm vasculature resulting in chronic lung disease -Small number of airways -Simple arterial branching pattern -Increased smooth muscle mass in resistance vessels -Left ventricular abnormalities

Question 38

What is the clinical presentation of CDH?

Answer 38

-Symptoms appear within mins to hrs. classic triad: - dyspnea -cyanosis -apparent dextrocardia physical exam reveals: -bulding chest and scaphoid abdomen -decreased breath sounds -distant or right displaced heart sounds -bowel sounds in chest -CXR bowel loops in the chest and mediastinal shift Dextrocardia- heart points to the right instead of the left

Question 39

What are the medical management goals of CDH?

Answer 39

medical stabilization for 24-48 hrs before surgery -maximize arterial oxygenation: - intubation -mechanical ventilation - low inflating pressures (<20-30cm h2o) - maintain muscle relaxation -improve pulm perfusion -correct acidosis -prevent hypothermia -prevent pain

Question 40

When can surgery occur for CDH?

Answer 40

when BP normal and stable for 24 hrs preductal sat >85 (preferably 90-95%) w fio2 less than 50% lactate < 3 UOP 1-2ml/kg/hr

Question 41

How can you improve pulm perfusion in CDH?

Answer 41

hyperventialtion (paco2 25-30 mmhg) fentanyl infusion minimal handling nitric oxide ECMO early intubation and decompression of stomach is critical

Question 42

What are the complications of ECMO?

Answer 42

-Bleeding at cannulation sites -intracranial hemorrhage -sepsis -HTN -brain death

Question 43

What is the criteria for ECMO?

Answer 43

More than 2kgs gestation >35 weeks