Pediatric Surgery Lecture Notes PDF

PEDIATRIC SURGERY MARIAN SAFAOUI, MD ASSOCIATE PROFESSOR OF SURGERY WESTERN UNIVERSITY COMP  Copies of documents used in this course were made available under Section 107 of the Copyright Act...

PEDIATRIC SURGERY MARIAN SAFAOUI, MD ASSOCIATE PROFESSOR OF SURGERY WESTERN UNIVERSITY COMP  Copies of documents used in this course were made available under Section 107 of the Copyright Act of 1976, the Fair Use Statute. This material has been made available solely for use in this class and the material may not be further C O P YR I G H T distributed to any person outside P R O T E C T ED the class, whether by copying or L EC T U R E M AT E R IA L by transmission in electronic or paper form. If Fair Use does not apply, copyright permission to reproduce these documents has been applied for or granted through the Copyright Clearance Center or the copyright owner.  NO FINANCIAL DISCLOSURES. DIS CLOS URES I AM NOT RESPONSIBLE FOR ANY INACCURACIES OR ERRORS IN THE CLOSED CAPTION TRANSCRIPTION OF THIS LECTURE.  OBJECTIVES Understand abdominal pain in the pediatric population. Understand the importance of bilious vs. nonbilious emesis Know what conditions are surgical emergencies Know the “buzz words” for the classic presentations, diagnoses, radiographic studies and treatments for the common pediatric GI complaints.  TOPICS Esophageal atresia Congenital diaphragmatic hernia Pyloric stenosis Malrotation Gastroschisis Volvulus Omphalocele Intestinal atresia Biliary atresia Intussusception Annular pancreas Hirschsprung disease Meckel’s diverticulum Necrotizing enterocolitis  ESOPHAGEAL ATRESIA Blind esophageal pouch with or without a fistula between the esophagus and airway. Polyhydramnios seen in pregnancy. Incidence 1:3000 Associated with VACTERL Vertebral Anorectal Cardiac* Tracheoesophageal Renal Limb Most common Type C (EA with distal TEF) 2nd most common is Type A (EA without fistula) CLINICAL PRESENTATION Newborn who develops excessive drooling and secretions within first hours of life. Choking with attempted feeding. Cyanosis and Respiratory distress Type C will give abdominal distention with crying.  DIAGNOSIS Failure to pass NG/OG tube into stomach  I MAG IN G Plain film of abdomen Atresia without fistula = gasless abdomen Atresia with fistula = gas in abdomen.  D IAGNO S IS Can also diagnose prenatally with MRI and US (shows polyhydramnios and failure to visualize stomach)  TREATMENT Must rule out Surgical VACTERL anomalies Up to 40% will have Echo to determine what cardiac anomalies side aortic arch is on Best predictor of survival Primary esophagoesophagostomy.  CONGENITAL DIAPHRAGMATIC HERNIA PARAESOPHAGEAL HIATAL HERNIA Courtesy of SpringerImages  CDH 1:2000-4000 live births 8% of all major congenital anomalies Mortality rate as high as 60% Associated with pulmonary hypoplasia and pulmonary hypertension Failure of pleuroperitoneal membrane to fuse.  TYPES OF CDH Bochdalek Morgagni More common Less common 90% are this type 10% Found posteriorly or in Found anteriorly or in the “back” the “front” Most commonly Herniates through associated with left- Foramen of Morgagni sided CDH Associated with right- sided CDH  FETAL SU RGERY  OMPHALOCELE Defect in abdominal wall at the site of the umbilical ring in which bowel and solid viscera protrude. Covered by peritoneum and amniotic membrane. Umbilical cord inserts into sac. Found in 1:5,000 live births. Giant omphalocele Defect > 4 cm and contains liver Found in 1:10,000 live births Associated with congenital anomalies  CONGENITAL ABNORMALITIES Present in 60% to 70% of cases Exstrophy of cloaca Most common abnormality is Beckwith-Wiedemann cardiac (20-40%) Macroglossia Also associated with chromosomal Macrosomia abnormalities Hypoglycemia Can be seen with prematurity in Visceromegaly 10-50% of cases and intrauterine Cantrell’s pentalogy growth restriction Lower thoracic wall malformations Ectopic cordis Anterior midline diaphragmatic hernia Cardiac anomalies  TREATMENT Maintain body temperature Cover omphalocele to reduce fluid loss (silo).  The subsequent treatment and outcome are determined by the size. Small and medium have a better prognosis. DEFINITIVE TREATMENT Repair primarily Resect May add membrane and prosthetic close fascia. material  GASTROSCHISIS  Defect in the anterior abdominal wall through which intestinal contents freely protrude.  No overlying sac so intestinal contents are bathed in peritoneal fluid.  Defect located at junction of the umbilicus and skin and is almost always to right of umbilicus.  Not commonly associated with congenital anomalies.  10% rate of intestinal atresia  Defect 16 mm and pyloric thickness of >4 mm.  TREATMENT Must fluid resuscitate and correct the metabolic alkalosis first! Once electrolytes are normal, then surgical intervention. Fredet-Ramstedt pyloromyotomy Open or laparoscopic splitting the pyloric muscle until the submucosa bulges upward. The incision begins at the pyloric vein of Mayo and extends onto the gastric antrum  INTESTINAL OBSTRUCTION IN NEWBORN The cardinal symptom of intestinal obstruction in the newborn is bilious emesis. Proximal obstruction High – emesis shortly after birth with minimal abdominal distention (can range from paucity of gas to no distal air) Must rule out malrotation with midgut volvulus!!!! Distal obstruction Low – abdominal distention and then onset of emesis. Delayed or absent stooling. Differential includes imperforate anus, meconium ileus, NEC, atresia, Hirschsprung  IMAGING Abdominal films in the supine and upright (left lateral decubitus) views. May need contrast because neonatal bowel lacks haustra or plicae circulares UGI Contrast enema (barium or gastrografin)  MALROTATION Malrotation with volvulus accounts for 10% of neonatal intestinal obstructions. Present in the first 3 weeks of life with bilious emesis. Intrauterine volvulus may cause intestinal obstruction or perforation at birth. Older children and adults with undiagnosed malrotation typically present with chronic GI symptoms of nausea, vomiting, diarrhea, abdominal pain, dyspepsia, bloating, and early satiety. Most common cause of malrotation is nonrotation Volvulus is the mesentery twisting around the SMA (clockwise) MIDGUT VOLVULUS IS A SURGICAL EMERGENCY  MIDGUT VOLVULUS Most commonly seen Bilious vomiting is first Can occur at any age. in the first few weeks of life. sign. Abdominal films show Treatment a paucity of gas throughout the Resuscitate then intestine with a few exploratory scattered air-fluid laparotomy levels  MALROTATION WITHOUT VOLVULUS Best diagnosed with UGI Shows incomplete rotation with duodenojejunal junction displaced to the right Corkscrew appearance is diagnostic of volvulus  IMAGING UGI is gold standard For malrotation. DO NOT PERFORM ON A PATIENT IN SHOCK OR WITH MIDGUT VOLVULUS. Normal C loop of duodenum Duodenum crosses midline Ligament of Treitz is right of midline and at level of pylorus or above. Plain films can show “double bubble” CT and US show “whirlpool sign”  TREATMENT Surgical treatment Ladd Procedure Division of abnormal peritoneal bands (Ladd’s bands) Correct malrotation (turn counterclockwise) Restore broad based mesentery Appendectomy Midgut volvulus is one of the most common indications for small bowel transplant in children.  DUODENAL Extrinsic OBSTRUCTION Congenital peritoneal bands associated with malrotation Annular pancreas Duodenal duplication Intrinsic Stenosis Mucosal diaphragm Duodenal atresias  ANNULAR PANCREAS Due to incomplete rotation of the ventral pancreatic bud resulting in the pancreas encircling the 2nd part of the duodenum. Associated with trisomy 21.  IMAGING Prenatal ultrasound (polyhydramnios) Abdominal plain films with “double bubble” sign Barium enema can help determining atresias in the lower GI tract. PANCREAS DIVISU M  ATRESIAS Intestinal atresias or stenosis account for 1/3 of all neonatal intestinal obstructions Can be anywhere in GI tract Esophageal Pylorus Duodenal Jejunoileal Colonic Imperforate anus The more distal the obstruction, the more distended the abdomen and the more air-fluid levels seen on abdominal plain film  DUODENAL ATRESIA Bilious emesis without Associated with Trisomy abdominal distention (due First 24 hours of life 21 (1/3) and other to proximal level of obstruction). congenital anomalies “Double Bubble” on Most common cause abdominal plain film 85% are distal to ampulla of obstruction in If no distal air then no further of Vater studies are indicated newborns (