Pediatric Surgery Review

1. Pediatric Surgery Review

2. 1. An 8 hr old infant drools and returns his first feed. A tube in passed into the esophagus and a film obtained. What is the diagnosis?

3. Esophageal Atresia and Tracheoesophageal Fistula • Incomplete partitioning of primitive foregut • 5 types of atresias • Esophageal atresia with distal TEF most common 8% 1% 85% 2% 4%

4. Esophageal Atresia and Tracheoesophageal Fistula • Can be part of VACTERL anomalies • vertebral, anal, cardiac, TEF, renal, limb • Atresias detected by inability to pass NGT/OGT • TEF w/o atresia presents with recurrent aspiration • Low-risk infants should get primary repair • long gap (>3 vertebral bodies) repair is delayed • high-risk babies get gastrostomy • Post-op complications include esophageal leak, dysmotility, GE reflux, strictures

5. 2. A 5-wk-old boy presents with 3 days of non-bilious projectile vomiting and dehydration. Which of the following is TRUE about his condition? • A. Immediate laparotomy is warranted. • B. UGI series is the diagnostic procedure of choice. • C. Delay in diagnosis leads to metabolic acidosis. • D. Most commonly seen in females. • E. Fluid replacement consists of ½ NS + KCL

6. 2. A 5-wk-old boy presents with 3 days of non-bilious projectile vomiting and dehydration. Which of the following is TRUE about his condition? • A. Immediate laparotomy is warranted. • B. UGI series is the diagnostic procedure of choice. • C. Delay in diagnosis leads to metabolic acidosis. • D. Most commonly seen in females. • E. Fluid replacement consists of ½ NS + KCL

7. Pyloric Stenosis • 1 in 600 births, male: female ratio 4:1, 3-12 weeks • Gastric outlet obstruction due to hypertrophy of pyloric muscle • Progressive, projectile non-bilious vomiting • Hypochloremic, hypokalemic metabolic alkalosis • renal compensation for hypovolvemia • Sono is diagnostic procedure of choice • thickness > 5 mm, channel length > 15 mm • Repair via Fredet-Ramstedt pyloromyotomy

8. Pyloromyotomy

9. 3. A 6-wk-old infant presents with jaundice. A sonogram appears normal. HIDA scan fails to demonstrate emptying into the duodenum. What is the next best step in management? • A. List for liver transplant. • B. Follow closely until 3 months of age, then do Kasai. • C. Percutaneous liver biopsy. • D. Initiate anti-inflammatory therapy. • E. Laparotomy with operative cholangiogram and liver biopsy, then Kasai if warranted.

10. 3. A 6-wk-old infant presents with jaundice. An abdominal USG appears normal. HIDA scan fails to demonstrate emptying into the duodenum. What is the next best step in management? • A. List for liver transplant. • B. Follow closely until 3 months of age, then do Kasai. • C. Percutaneous liver biopsy. • D. Initiate anti-inflammatory therapy. • E. Laparotomy with operative cholangiogram and liver biopsy, then Kasai if warranted.

11. Biliary Atresia • Fibrous obliteration of extrahepatic bile ducts • 1 in 10-15 thousand births • Jaundice, conjugated hyperbilirubinemia, firm hepatomegaly due to biliary cirrhosis • Lab work up should include LFTs, Alpha-1 antitrypsin, TORCH infections, sweat test, hepatitis • Sono shows no extrahepatic ducts, tiny gallbladder • HIDA scan reveals no emptying into the duodenum • Liver biopsy reveals cholestasis and bile duct proliferation

12. Kasai Portoenterostomy • Roux-en-Y limb of jejenum sutured to porta where atretic bile ducts exit hepatic parenchyma • Results depend on age (10 weeks), anatomy and histology of atretic bile ducts, ? degree of cirrhosis • overall: 1/3 fail immediately • Long term survival in 25% of those that have drainage • Results of liver transplantation not affected by Kasai procedure

13. Biliary Atresia

14. Kasai Portoenterostomy

15. 4. Which of the following is TRUE regarding duodenal atresia? • A. It is associated with trisomy 21 in 10% cases. • B. Abdominal X-ray is usually normal. • C. Results from disruption of fetal blood supply. • D. Operative repair involves duodenal resection. • E. Concomitant abnormalities can include annular pancreas, esophageal atresia, or VACTERL lesions.

16. 4. Which of the following is TRUE regarding duodenal atresia? • A. It is associated with trisomy 21 in 10% cases. • B. Abdominal X-ray is usually normal. • C. Results from disruption of fetal blood supply. • D. Operative repair involves duodenal resection. • E. Concomitant abnormalities can include annular pancreas, esophageal atresia, or VACTERL lesions.

17. Duodenal Atresia • Failure to recanalize lumen of duodenum after solid phase of embryologic development • Associated with Down’s syndrome in 30% • Vomiting can be bilious or non-bilious • Abdominal X-ray shows “double-bubble” • Best repaired by bypass -> duodenoduodenostomy or duodenojejunostomy • no indication to divide annular pancreas

18. Duodenal Atresia

19. 5. A 3-wk-old baby, previously well, presents with sudden onset of bilious vomiting. What study is most appropriate? • A. Abdominal X-ray. • B. CT scan. • C. Upper GI series. • D. Barium enema. • E. Esophageal pH studies.

20. 5. A 3-wk-old baby, previously well, presents with sudden onset of bilious vomiting. What study is most appropriate? • A. Abdominal X-ray. • B. CT scan. • C. Upper GI series. • D. Barium enema. • E. Esophageal pH studies.

21. Malrotation • Lack of retroperitoneal fixation of bowel and presence of Ladd’s bands • partial or complete duodenal obstruction • bowel may twist around SMA axis = volvulus • up to 75% present w/in 1st month of life • Volvulus may present as pain, rectal bleeding, cardiovascular collapse w/ metabolic acidosis • untwist in direction of normal rotation (CC for surgeon) • UGI shows duodenojejunal junction to the R of midline, more cephalad

22. Malrotation

23. 6. A 1.5 kg, 30-wk preemie develops abdominal distention and bloody stool after 1st feedings. Which of the following is TRUE regarding his condition? • A. Supportive treatment includes stopping all feeds, NGT drainage, IVF, serial abdominal exams and radiographs. • B. IV antibiotics not indicated unless pathogen identified. • C. Barium enema is the imaging modality of choice. • D. Overall mortality reported as 50-60%. • E. Intestinal stricture formation is rare.

24. 6. A 1.5 kg, 30-wk preemie develops abdominal distention and bloody stool after 1st feedings. Which of the following is TRUE regarding his condition? • A. Supportive treatment includes stopping all feeds, NGT drainage, IVF, serial abdominal exams and radiographs. • B. IV antibiotics not indicated unless pathogen identified. • C. Barium enema is the imaging modality of choice. • D. Overall mortality reported as 50-60%. • E. Intestinal stricture formation is rare.

25. Necrotizing Entercolitis (NEC) • Idiopathic mucosal intestinal injury, may progress to transmural necrosis • 1/2 patients < 1500 g, 80% < 2500 g at birth • Signs: feeding intolerance , vomiting abdominal distention progressive sepsis autonomic instability (B’s and D’s) abdominal wall erythema +/- mass • Labs: metabolic acidosis thrombocytopenia

26. Necrotizing Enterocolitis (NEC) • X-rays: distended loops c/w ileus, pneumatosis intestinalis

27. Necrotizing Enterocolitis (NEC) • Indications for OR are free air (absolute), fixed abdominal mass, abdominal wall erythema, failure to improve (controversial) • OR for resection of dead bowel, formation of stomas • “second-look laparotomy” 24-48 hrs if needed Long-term complication of intestinal strictures and short bowel syndrome Overall mortality 20-40%

28. 7. Which of the following is FALSE regarding meconium ileus? • A. Underlying diagnosis is usually cystic fibrosis. • B. Most often requires operative intervention. • C. Presents as a neonatal bowel obstruction. • D. X-rays may reveal a stippled pattern in the RLQ (“soap bubble” sign). • E. May be relieved by water-soluble contrast enema.

29. 7. Which of the following is FALSE regarding meconium ileus? • A. Underlying diagnosis is usually cystic fibrosis. • B. Most often requires operative intervention. • C. Presents as a neonatal bowel obstruction. • D. X-rays may reveal a stippled pattern in the RLQ (“soap bubble” sign). • E. May be relieved by water-soluble contrast enema.

30. Meconium Ileus • Newborn bowel obstruction secondary to inspissated meconuim in distal ileum • Enema reveals microcolon -> may be therapeutic • Non-operative management successful in 2/3 • OR required for perforation or failed enema • may flush bowel with N-acetylcysteine in saline • Bishop-Koop as option if stoma required -> end-to-side w/ proximal end of distal bowel brought out as stoma

31. 8. A listless 9-month-old boy presents with acute onset of severe intermittent abdominal pain. Rectal exam is guaiac positive. What is the most likely diagnosis? • A. Meckel’s diverticulum. • B. Acute appendicitis. • C. Intussusception. • D. Intestinal polyp. • E. Gastritis.

32. 8. A 9-month-old boy presents with acute onset of crampy abdominal pain. Rectal exam is guiac positive. What is the most likely diagnosis? • A. Meckel’s diverticulum. • B. Acute appendicitis. • C. Intussusception. • D. Intestinal polyp. • E. Gastritis.

33. Intussusception • Commonly affects children 3 months to 2 yrs • severe crampy abdominal pain (every 10-20 minutes) • vomiting, “currant jelly” stools • tender, sausage-like mass in RUQ • Telescoping of terminal ileum into large intestine • Contrast enema for diagnosis will reduce 80% • air pressure to 120 mmHg, barium to 100 cm H2O • 10% recurrence, often within hours • OR reduction if not reduced radiographically • 5% of patients need resection

34. 9. A full-term newborn has not passed meconuim by DOL 2. Which of the following is FALSE regarding his likely diagnosis? • A. It is more common in males. • B. Suction rectal biopsy is rarely adequate for diagnosis. • C. Enterocolitis is a significant cause of mortality. • D. Disease is most often confined to the distal colon. • E. Barium enema may be normal.

35. 9. A full-term newborn has not passed meconuim by DOL 2. Which of the following is FALSE regarding his likely diagnosis? • A. It is more common in males. • B.Suction rectal biopsy is rarely adequate for diagnosis. • C. Enterocolitis is a significant cause of mortality. • D. Disease is most often confined to the distal colon. • E. Barium enema may be normal.

36. Hirschsprung’s Disease • Absence of ganglia in submucosal and myenteric plexuses • variable proximal extension of aganglionosis • lack of peristalsis and failure of sphincter relaxation • rectosigmoid only in 75%, entire colon in 8% • Presents as failure to pass meconium w/in 24 hrs or constipation in older child • Diagnosis best made by rectal biopsy • suction adequate if submucosa present

37. Hirschsprung’s Disease • OR requires biopsies to confirm ganglion cells in normal bowel • “Pull-through” operations • Swenson: complete excision, anastamosis to proximal anal canal at columns of Morgagni • Soave: endorectal mucosal excision, pull through rectal muscular sleeve • Duhamel: retains portion of aganglionic bowel anteriorly using GIA stapler

38. 10. Which of the following statements is TRUE with respect to neonatal abdominal wall defects? • A. The bowel in omphalocele is covered by a sac. • B. Gastroschisis is frequently associated with other anomalies. • C. A Silastic silo is rarely employed in management of these defects. • D. Mortality is higher in gastroschisis. • E. Operative management of omphalocele usually requires bowel resection.

39. 10. Which of the following statements is TRUE with respect to neonatal abdominal wall defects? • A. The bowel in omphalocele is covered by a sac. • B. Gastroschisis is frequently associated with other anomalies. • C. A Silastic silo is rarely employed in management of these defects. • D. Mortality is higher in gastroschisis. • E. Operative management of omphalocele usually requires bowel resection.

40. Omphalocele • Occur 1 in 5000 live births, more common in boys • over 50% have associated cardiac, GI, GU, musculoskeletal, or CNS anomalies • Herniation of abdominal contents through defective umbilical ring • overlying sac of outer amnion and peritoneum • umbilical cord in continuity with sac • liver involved in larger defects • High mortality (30-60%) due to other anomalies

41. Omphalocele

42. Omphalocele • Non-operative management with escharotic agent • OR for reduction and closure of abdominal wall • keep intra-abdominal pressure < 20 mmHg • large defects require skin flap or prosthetic • Silastic silo most common, reduce daily for 3-10 days • Post-op complications include sepsis, GE reflux, inguinal hernias, abdominal wall hernia

43. Gastroschisis • Anterior abdominal wall defect (“belly cleft”) • usually to right of umbilical cord • no sac or membrane covering contents • exposed bowel thick, edematous, exudative peel • associated intestinal atresias in 10% • Initial management • aggressive fluid replacement (2-3X normal) • protection of exposed bowel w/occlusive dressing

44. Gastroschisis

45. Gastroschisis • Primary reduction and closure in 80-90% cases • Silastic silo if high intra-abdominal pressure • may require resection if exposed bowel non-viable • Post-op complications: abdominal compartment syndrome • sepsis, necrotizing enterocolitis abdominal wall cellulitis prolonged ileus short gut syndrome w/ TPN dependence

46. 11. A 3-year-old girl is referred to you with fever, failure to thrive, periorbital ecchymoses, and a large abdominal mass. What is the most likely diagnosis? • A. Hepatoblastoma • B. Wilms tumor • C. Neuroblastoma • D. Ovarian teratoma • E. Rhabdomyosarcoma

47. 11. A 3-year-old girl is referred to you with fever, failure to thrive, periorbital ecchymoses, and a large abdominal mass. What is the most likely diagnosis? • A. Hepatoblastoma • B. Wilms tumor • C. Neuroblastoma • D. Ovarian teratoma • E. Rhabdomyosarcoma

48. Neuroblastoma • Most common extracranial solid tumor in children • median age of onset is 2 years • over 90% present by 8 years • Arises from the neural crest • 60% in abdomen (mostly from the adrenal gland) • thoracic tumors next most common (posterior mediastinum) • Genetic abnormalities common (80%) • short arm chromosome 1, N-myc amplification, MDR gene, DNA ploidy

49. Neuroblastoma • Most commonly presents with abdominal mass • constitutional symptoms: fever, weight loss, anemia, FTT, bone pain • Metastases at presentation in 3/4 of patients • bone, BM, and lymph nodes most common • liver and skin less frequently, rare lung and brain • X-rays may reveal stippled calcifications • Pre-treatment staging essential • CT scan, MIBG scan, BM biopsy, urine catacholamines

50. Neuroblastoma