3. Hypertrophic pyloric stenosis


1. Introduction: Hypertrophic pyloric stenosis (HPS) causes obstruction of the upper GI tract, but the infant frequently does not have symptoms until 2 to 4 weeks of age. HPS results in thickening, or hypertrophy, of the pyloric sphincter located at the distal end of the stomach; this causes a mechanical intestinal obstruction that becomes increasingly evident as the infant begins to consume larger amounts of formula during the early weeks of life. Pyloric stenosis is five times more common in boys than girls and is most often found in full-term Caucasian infants. The exact etiology remains unknown; however, there does seem to be a genetic predisposition.
2. Assessment:
   1. Classic symptom is vomiting:
   1. Begins as nonprojectile at age 2-4 weeks.
   2. Advances to projectile at age 4-6 weeks.
   3. Vomitus is non-bile stained (stomach contents only).
   4. Most often occurs shortly after a feeding.
   5. Major problem is the mechanical obstruction of the flow of stomach contents to the small intestine due to the anatomical defect of stenosis of the pyloric sphincter.
   6. No apparent nausea or pain, as evidenced by the fact that infant eagerly accepts a second feeding after episode of vomiting.
   7. Metabolic alkalosis develops due to loss of hydrochloric acid.
   2. Inspection of abdomen reveals:
      1. Palpable olive-shaped mass in right upper quadrant.
      2. Visible peristaltic waves, moving from left to right across upper abdomen.
   3. Weight: fails to gain or loses.
   4. Stools: constipated, diminished in number and size - due to loss of fluids with vomiting.
   5. Signs of dehydration may become evident.
   6. Upper GI series reveals:
      1. Delayed gastric emptying.
      2. Elongated and narrowed pyloric canal.
3. Analysis/nursing diagnosis:
   1. Fluid volume deficit related to vomiting.
   2. Altered nutrition, less than body requirements, related to vomiting.
   3. Risk for injury/infection related to altered nutritional state.
   4. Impaired skin integrity related to dehydration and altered nutritional state.
   5. Knowledge deficit related to cause of disease, treatment and surgery, prognosis, and followup care.
4. Nursing care plan/implementation:
   1. Goal (preoperative): restore fluid and electrolyte balance.
      1. Generally NPO, with IVs preoperatively to provide fluids and electrolytes.
      2. Observe and record I&O, including vomiting and stool.
      3. Weight: check every 8 hr or daily.
      4. Monitor laboratory data.

Signs and Symptoms of Dehydration in Infants and Young Children

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• Weight loss (most important variable to assess): mild dehydration (less than 5% weight loss); moderate dehydration (5-9% weight loss); severe dehydration (10-15% weight loss)
• Skin: gray, cold to touch, poor skin turgor (check skin across abdomen)
• Mucous membranes: dry oral buccal mucosa; salivation absent
• Eyes: sunken eyeballs; absence of tears when crying
• Anterior fontanel (in infant): sunken
• Shock: increased pulse, increased respirations, decreased blood pressure
• Urine: oliguria, increased specific gravity, ammonia odor
• Alterations in level of consciousness: irritability, lethargy, stupor, coma, possible seizures
• Metabolic acidosis (with diarrhea)
• Metabolic alkalosis (with vomiting)

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2. Goal: provide adequate nutrition.
   1. Maintain NPO with IVs for 4-6 hours postoperatively, as ordered (can offer pacifier).
   2. Follow specific feeding regimen ordered by doctor - generally start with clear fluids in small amounts hourly, increasing slowly as tolerated. Full feeding schedule reinstated within 48 hr. Offer pacifier between feedings.
   3. Fed only by RN for 24-48 hours, because vomiting tends to continue in immediate postoperative period.
   4. Burp well - before, during, and after feeding.
   5. Position after feeding: high Fowler, turned to right side; minimal handling after feeding to prevent vomiting.
3. Goal (preoperative and postoperative): institute preventive measures to avoid infection or skin breakdown.
   1. Use good hand-washing technique.
   2. Administer good skin care, especially in diaper area (urine is highly concentrated); give special care to any reddened areas.
   3. Give mouth care when NPO or after vomiting.
   4. Tuck diaper down below suture line to prevent contamination with urine (postoperatively).
   5. Note condition of suture line - report any redness or discharge immediately.
   6. Screen staff and visitors for any sign of infection.
4. Goal: do discharge teaching to prepare parents to care for infant at home.
   1. Teach parents that defect is anatomical and unrelated to their parenting behavior/skill.
   2. Demonstrate feeding techniques, and remind parents that vomiting may still occur.
   3. Stress that repair is complete; this condition will never recur.
   4. Instruct parents in care of the suture line: no baths for 10 days, tuck diaper down, report any signs of infection promptly.
   5. Offer follow-up referrals as indicated.
5. Evaluation/outcome criteria:
1. Infant survives surgical repair without untoward difficulties (including infection/skin breakdown).
2. Adequate nutrition is maintained, and infant begins to grow and gain weight.
3. Parents verbalize confidence in their ability to care for their infant on discharge.