Peds Flashcards
What are the most common causes of respiratory distress in newborns?
- Transient tachypnea of newborn: residual pulmonary fluid in lung
- Hyaline membrane disease / respiratory distress syndrome
- Meconium aspiration syndrome
In a newborn with respiratory distress, what should we do to confirm/rule out common surgical diagnoses?
Place OGT/NGT
Get CXR
What signs in a newborn suggest congenital diaphragmatic hernia (CDH)?
Severe resp distress
Absent breath sounds
Scaphoid abdomen
How is CDH usually diagnosed?
In utero: prenatal US
Where do CDH most commonly occur?
L side: posterolateral/Bochdalek hernia
What does herniation of abdominal contents in CDH cause?
Pulmonary hypoplasia: ipsi and contra
What is the pathophysiology of respiratory distress in CDH?
Pulm HTN –> Decreased pulm blood flow / hypoxia
Pulm hypoplasia –> decreased gas exchange and CO2 retention
What common associated anomalies occur with CDH?
Chromosomal defects Rotational Cardiac (VSD/ASD) CNS Limb GU
What is mortality related to in CDH?
Degree of pulmonary hypoplasia / Pulmonary HTN
Presence of congenital anomalies
What is the first step in management of newborn respiratory distress?
Immediate intubation
What is the first step in management of newborn respiratory distress?
Immediate intubation
What is survival related to in CDH?
Degree of pulmonary hypoplasia and HTN
What is the goal of treatment for CDH?
provide pulmonary support w/o further damaging the lungs
When is the optimal timing for surgery for CDH: immediate or wait?
Delay: allow lungs to mature and pulmonary HTN to improve
Before surgery for CDH, what must be done?
Evaluate for other congenital anomalies
Why must blow-by oxygen or excessive bag mask ventilation be avoided in CDH?
Worsens lung compression and mediastinal shift
What happens with CDH?
Failure of septum transversum to completely divide the pleural and coleomic cavities during fetal development
What’s the most important step in clinical management for CDH?
Immediate intubation
What’s the best initial diagnostic test for newborn respiratory distress?
OGT + CXR
What do we think: bilious vomiting in a newborn 0-1 month?
Surgical problem until proven otherwise
Does passage of meconium rule out obstruction?
No: mucuous and epithelium is shed along entire length of intestine - distal to the obstruction, it may still pass!
In a stable newborn with bilious vomiting, what is the first step?
Plain abdominal XR to rule out perforation, prox vs. distal obstruction, presence or absence of distal gas
What are the key features on XR of duodenal obstruction/atresia?
Double bubble sign + no distal gas
If a newborn with bilious vomiting has distal gas, what’s the most likely diagnosis?
Malrotation + midgut volvulus before duodenal web or partial duodenal obstruction
What causes duodenal atresia?
failure of recanalization early in development
> 50% of patients with duodenal atresia have what associated anomalies?
Trisomy 21
Annular pancreas
Cardiac (most common)
What is the management for a newborn with bilious vomiting?
- Get IV access: Correct fluid/electrolyte abnormalities
- Place NGT
- Rule out other anomalies prior to surgery
If a newborn with bilious vomiting is unstable, what do we suspect? Next steps?
Suspect malrotation with midgut volvulus
Go to OR emergently
What is the procedure of choice for duodenal atresia?
Duodenoduodenostomy
How can duodenal atresia present with non bilious vomiting?
Obstruction proximal to the ampulla: present with nonbilious emesis
What key comorbidity must be identified before surgery for duodenal atresia? Why?
Annular pancreas: Injury to the ring of pancreatic tissue can lead to pancreatic enzyme leak and pancreatitis
What is bilious emesis?
Green or yellow emesis
What type a problem is bilious emesis in an infant?
Surgical until proven otherwise!
In a stable infant with bilious emesis, what is the first step?
Plain abdominal radiograph first to exclude gross perforation
If initial XR is negative in an infant with bilious emesis, what is the next step?
UGI contrast study: evaluate duodenum and proximal SI
In infants with bilious vomiting, what MUST we suspect first due to danger?
Malrotation with midgut volvulus
What is the midgut embryologically?
SMA: Second portion of duodenum to 2/3 of transverse colon
What is malrotation in the gut due to?
Developmental failure of normal 270 degree counterclockwise midgut rotation
What is the classic pattern of congenital malrotation?
narrow mesenteric base
Ligament of Treitz located R of midline, cecum in epigastrium, Ladd’s bands from cecum to RUQ crossing duodenum
What is a volvulus in setting of malrotation?
Midgut rotates around SMA axis causing duodenal obstruction and vascular compromise of bowel
What is the classic UGI radiograph of volvulus in setting of malrotation?
“corkscrew” appearance of contrast in bowel lumen
What is the management of treating midgut volvulus?
- Place NGT to decompress stomach
- Give ABx / IVF while prepping for laparotomy
- Laparotomy
What is the first management step of treating hemodynamically unstable acute GI obstruction in an infant?
- Rapid fluid resuscitation
2. Immediate surgical intervention w/o additional studies!
What is Ladd’s procedure?
Relieving obstruction by untwisting the bowel and brooding the mesenteric base to prevent future episodes
How can malrotation with midgut volvulus present (2 ways)?
Bilious or non bilious vomiting depending on location
What is the most common bowel gas pattern in malrotation with midgut volvulus?
Normal
During surgery in an infant with bilious emesis, what must be ruled out?
Duodenal stenosis / atresia
In newborn with bilious emesis whose XR shows proximal obstruction: distal bowel gas + “double bubble”, what is the next step?
UGI contrast study: should show malrotation +- midgut volvulus
In a newborn with bilious emesis whose XR shows “double bubble” w/o distal gas, what is the diagnosis?
Duodenal atresia
In an newborn with bilious emesis whose XR shows distal obstruction with multiple loops of dilated small bowel, what is the next step and likely diagnoses?
Contrast enema:
- Intestinal atresia
- Meconium ileus
- Hirschsprung’s disease
Of patients with non bilious emesis in infancy, which disease are managed medically?
Acute gastroenteritis
GERD
Metabolic d/o
Pylorospasm
Of patients with non bilious emesis in infancy, which disease are managed surgically?
Antral web
Enteric duplication cyst
GERD
Pyloric atresia / stenosis
What is the most common surgical cause of non bilious vomiting in an infant?
Hypertrophic pyloric stenosis (HPS)
What is classic PE sign of HPS?
Palpable RUQ “olive” mass with visible peristalsis over the epigastrium
If diagnosis of HPS is unclear, what should be done?
US
What is the diagnostic criteria for HPS?
- Pyloric length > 15mm
- Thickness > 3mm
What electrolyte abnormalities are common in HPS?
- Hypochloremic, hypokalemic, metabolic acidosis
- Paradoxical aciduria
What is pathophysiology of HPS?
Hyperplasia and hypertrophy of pylorus –> GOO
What is the first treatment for HPS?
- Fluid resuscitation
2. Correct electrolyte imbalances
What is the gold standard surgery for HPS?
Ramstedt pyloromyotomy: incise and split the muscular layers, leaving the mucosa and submucosa intact
When is the optimal timing of surgery for HPS?
Delay until infant resuscitated and electrolyte levels are normal
When does feeding start after HPS repair? What is common?
After surgery - vomiting may occur but should resolve
If a patient has equivocal US suspicious for HPS or concern for malrotation with midgut volvulus, what else should be done? What is the risk
Contrast UGI
- Risk of aspiration
Is HPS a medical or surgical emergency?
Medical!
If an infant has persistent fever after surgery for HPS, what should be considered?
incomplete pyloromyotomy
If an infant has HPS surgery and has post-op fever and tachycardia, what must it be until proven otherwise?
perforation
How do we diagnose abdominal wall defects in newborns?
Prenatal ultrasound usually
What are key identifying features of gastroschisis?
Paraumbilical (R) and exposed bowel
What are key identifying features of omphalocele?
Sac from the umbilicus, associated with more congenital defects
What are the associated syndromes with omphalocele?
Beckwith-Wiedemann Syndrome
Trisomies 13, 18
Pentalogy of Cantrell
What is the etiology of gastroschisis?
In utero vascular insult causing abdominal wall defect
What is the etiology of omphalocele?
Arrest of cell migration causing incomplete return of midgut to the peritoneal cavity
What is the most important first 2 steps in management of abdominal wall defect in newborn?
- Ventilation: secure airway
- Normothermia and fluid management:
- Radiant heater
- Orogastric suction
- Protect exposed viscera with plastic wrap
- IV fluids + broad spectrum Abx
What is the definitive treatment for gastroscisis or omphalocele?
- Protective silo and serial reduction OR
- Surgical repair
What must a gastroschisis patient be evaluated for?
Atresia, ischia or volvulus
What must be given to a gastroschisis patient while they are awaiting reduction of the bowel or surgery? Why?
TPN - intestine likely inflamed
What are key considerations after post-op repair of gastroschisis or omphalocele?
- Ventilator if needed
- TPN if needed
- Monitor for abdominal compartment syndrome!
What’s in the differential for feeding intolerance in a newborn?
- Anatomic malformation of naso- and oropharynx, tracheobronchial tree and esophagus
- GERD
- Extrinsic esophageal compression
- Food sensitivity
- Neurologic d/o
What do desaturations only while feeding imply in a newborn?
Anatomic or functional problem w/ proximal aerodigestive tract
What is the best initial diagnostic test in a newborn with feeding intolerance?
AP and lateral chest XR after NG/OGT placement
What is the pathophysiology of EA +/- TEF?
Defect in development of longitudinal tracheoesophageal fold separating foregut into trachea and esophagus
What is the most common type of TEF?
Distal: Type C: Trachea with esophagus going off of it
Most patients with TEF +/- EA have what type of anomalies?
VACTERL: Vertebral Anorectal CV Tracheoesophageal Renal Limb
In patients with TEF +/- EA, what is prognosis for those with comorbidites or requiring surgery?
Excellent w/o comorbidiites
* Significant sequelae from surgery!
What is management in newborns with respiratory compromise?
Intubation/mechanical ventilation
What is the preoperative management goal in patient with TEF +/- EA?
Minimize risk of aspiration: NGT of upper esophageal pouch, head elevation, AB
In patients with TEF +/- EA, what must be done before surgery?
Eval for associated anomalies: echo, renal US, XRays
What is the surgical repair for TEF +/- EA?
Division of fistula tract, repair of trachea, primary anastomosis of esophagus
What are the post-operative complications from surgery for TEF +/- EA and how common are they?
Common!
- Anastomotic leak
- Stricture
- GERD
Why do we avoid contrast esophagram in newborns with suspected TEF +/- EA?
Risk of aspiration pneumonitis
Why do we avoid distending GI tract in patients with TEF +/- EA?
Avoid further aspiration and lung injury, esp in patients on ventilator support
What must be done before surgery for TEF +/- EA?
Assess vascular anatomy:
- IVC can drain into RA via azygous system
- 5% patients have R sided aortic arch