Case 62 - pyloric stenosis

Question 1

what is pyloric stenosis and what are the symptoms?

Answer 1

• circular muscular hypertrophy at pylorus
• produces gastric outlet obstruction
• 2-6 weeks of age

Symptoms

• non-bilious projective vomiting

Question 2

how do you diagnose pyloric stenosis?

Answer 2

physical exam

• olive-like mass in epigastric region to the right of midline

imaging

• ultrasound
• barium swallow
  
  • adds risk of aspiration pneumonitis

Question 3

Is pyloric stenosis a surgical emergency?

Answer 3

NO

• hypovolemia, electrolyte imbalance, and acid-base derangements should be corrected before surgical intervention

Question 4

what metabolic derangements are associated with pyloric stenosis?

Answer 4

1) Vomiting

• lose hydrogen, sodium potsasium, and chloride ions
• blood
  
  • hypochloremic, hypokalemic, metabolic alkalosis
• Urine
  
  • to maintain acid base balance, bicarb secreted in urine (alkalotic urine).
  • to maintain electrial neutrality, chloride is reabsorbed = dec urinary chloride conc

2) dehydration

• hypovolemia –> dec tissue perfusion –> metabolic acidosis
• increase aldosterone secretion

Question 5

what tx is necessary for pyloric stenosis pts pre-operativley

Answer 5

1) replete electrolytes
2) correct acid-base derangments
3) fluid resuscitation

• 0.9% NaCl
• administer glucose as well –> infants may have depleted glycogen liver stores due to malnutrition
• presence of normal plasma chloride level = adequate fluid resuscitation and electrolyte resuscitatoin

Question 6

what is surgical tx for pyloric stenosis?

Answer 6

laproscopic pyloromyotomy = circular muslces of pylorus are spread apart

Question 7

what are the anesthesia considerations for patients with pyloric stenosis?

Answer 7

1) medical emergency, not surgical emergency

2) pre-op correction of electrolyte, acid/base derangement, fluid status

3) prepare OR

• warm OR
• warming blankets / forced air warming device

4) monitors

• standard ASA monitor
• IV access pre-induction

5) pre-tx with atropine (avoid brady with suction and induction)
6) OG suction with large-bore catheter (14F)
* place infant in supine, right lateral and left lateral position while suctioning = decrease risk of regurg and aspiration
7) RSI with cricoid pressure

• considered full stomach
• can consider awake intubation –> longer time to intubate, reduced first attepmpt success rate, o2 desat and brady

Question 8

intraop anes mainteance for pyloric stenosis

Answer 8

anes mainteance

• inhaled anes or balanced anes with IV agents
• muscle relaxant not necessary
• glucose infusion during procedure to avoid hpoglycemia

Post-op

• tell sx to infiltrate wound for post op pain control and to minimze opioids
• extubate - awake and protective airway reflexes reestablished
• depending on age of infant - apnea monitoring post-op