Pyloric Stenosis Sara Chapman

Definition Progressive narrowing of the pyloric canal. Hypertrophied pyloric muscle. Occurs in infancy. Infantile hypertrophic pyloric stenosis. (Domino, Baldor, Golding, & Grimes, 2015). Pyloric stenosis is a progressive narrowing of the pyloric canal, caused by hypertrophied pyloric muscle. It occurs during infancy. Pyloric stenosis is also known as Infantile hypertrophic pyloric stenosis, or IHPS (Domino, Baldor, Golding, & Grimes, 2015 p. 1014)

pathophysiology Hypertrophy and hyperplasia of the 2 muscular layers of the pylorus leads to narrowing of the gastric antrum. The pyloric canal becomes lengthened, and the whole pylorus becomes thickened. Mucosa is edematous and thickened. The stomach can become markedly dilated in response to near-complete obstruction. Gastric outflow is obstructed. (Singh & Sinert, n.d.). Gastric distention and vomiting. (Domino, Baldor, Golding, & Grimes, 2015). Marked hypertrophy and hyperplasia of the 2 (circular and longitudinal) muscular layers of the pylorus occur. This leads to narrowing of the gastric antrum. The pyloric canal becomes lengthened, and the entire pylorus then thickens. The mucosa of the pylorus is edematous and thickened. In advanced cases of pyloric stenosis, the stomach is markedly dilated in response to a near-complete obstruction (Singh & Sinert, n.d.). Gastric outflow is obstructed which leads to gastric distention and vomiting (Domino, Baldor, Golding, & Grimes, 2015).

Pathophysiology Image retrieved from https://www.google.com/search?q=pyloric+stenosis+pathophysiology

etiology Exact cause is unknown. Use of Fluoxetine in the 1st trimester of pregnancy? Genetics? (Domino, Baldor, Golding, & Grimes, 2015, p. 1014). A recent study identified an association between pyloric stenosis and the use of Fluoxetine in the 1st trimester of pregnancy (Domino, Baldor, Golding, & Grimes, 2015, p. 1014). Recent studies have identified a link between pyloric stenosis and chromosome 11 and multiple loci (multiple locations of the gene), and chromosome 16 (Domino, Baldor, Golding, & Grimes, 2015, p. 1014).

Incidence & Risk Factors 3/1000 live births. 4x increase in males vs females. Familial. Most common in Caucasian first-born males. (Domino, Baldor, Golding, & Grimes, 2015, p. 1014). (Burns, Dunn, Brady, Starr, & Blosser, 2013, p. 980). Pyloric stenosis occurs in about every 3 out of 1000 live births. There are four times the number of male babies born with the condition as opposed to females. The condition tends to be familial. There is a 5x increased risk with an affected 1st degree relative (Domino, Baldor, Golding, & Grimes, 2015, p. 1014). . It is seen most commonly in Caucasian first-born males (Burns, Dunn, Brady, Starr, & Blosser, 2013, p. 980).

Screening Not routine. Screen if clinical findings consistent with pyloric stenosis…. (Next slide!)

Clinical findings History Typical onset is at 3-6 weeks of age. Projectile vomiting after feeding (non-bilious). Vomiting increasing in frequency and severity. Blood tinged emesis. Hunger. Weight loss. Decrease in bowel movements. (Domino, Baldor, Golding, & Grimes, 2015, p. 1014). Emesis may become blood tinged due to vomiting induced gastric irritation. Constant hunger is due to inadequate nutrition due to increased vomiting (Domino, Baldor, Golding, & Grimes, 2015, p. 1014). Image retrieved from https://www.google.com/search?q=pyloric+stenosis+pathophysiology Image retrieved fwww.google.com/search?q=pyloric+stenosis+pathophysiology rom https://

Clinical findings physical exam referred Clinical findings physical exam Early signs: Firm, mobile, “olive-like” mass palpable in the middle upper or RUQ. Epigastric distention. Visible gastric peristalsis after feeding. Late signs: Dehydration. Jaundice when inadequate nutrition leads to indirect hyperbilirubinemia (rare). (Domino, Baldor, Golding, & Grimes, 2015, p. 1014). RUQ “olive-like” mass can also be to as the olive sign.

Olive like mass Images retrieved from https://www.google.com/search?q=pyloric+stenosis+olive+sign Images retrieved from https://www.google.com/search?q=pyloric+stenosis+olive+sign

Differential diagnosis Inexperienced or inappropriate feeding. Gastroesophageal reflux disease. Gastritis. Congenital adrenal hyperplasia. Pylorospasm. Gastric volvulus. Antral or gastric web. (Domino, Baldor, Golding, & Grimes, 2015, p. 1014) (Congenital adrenal hyperplasia, n.d.) (Hope, 2013) (Bell, Ternberg, Keating, Moedjona, McAlister, & Shackelford, 1978). Congenital adrenal hyperplasia - is a collection of genetic conditions that limit your adrenal glands' ability to make certain vital hormones. Signs and symptoms - Ambiguous genitalia in girls, enlarged penis in boys, poor weight gain, weight loss, dehydration, vomiting (Congenital adrenal hyperplasia, n.d.) Gastric volvulus- an abnormal rotation of the stomach of more than 180°, creating a closed-loop obstruction that can result in incarceration and strangulation, very rare (Hope, 2013). Antral or gastric web – Rare. Wire-like transverse septum 1-2 cm proximal to the pylorus. Clinical findings consist of non-bilious, often projectile vomiting in infants less than 6 months of age. Older children complain of pain, vomiting, and fullness after eating (Bell, Ternberg, Keating, Moedjona, McAlister, & Shackelford, 1978).

considerations Prompt treatment to avoid dehydration and malnutrition. IV fluids to correct dehydration and metabolic abnormalities. Apnea monitoring. (Domino, Baldor, Golding, & Grimes, 2015, p. 1014) There is a tendency toward apnea to compensate with respiratory acidosis – in an attempt to correct metabolic alkalosis (due to dehydration which causes metabolic abnormalities) (Domino, Baldor, Golding, & Grimes, 2015, p. 1014)

Laboratory tests/diagnostics Check electrolytes CMP Bili Abdominal US is the study of choice Thickened and elongated pyloric muscle Upper GI series Strong gastric contractions (Domino, Baldor, Golding, & Grimes, 2015, p. 1014) Metabolic abnormalities are a late finding and are uncommon (Domino, Baldor, Golding, & Grimes, 2015, p. 1014)

Management/treatment non-pharmacologic Surgery Ramstedt pyloromyotomy – the entire length of the hypertrophied muscle is divided. The underlying mucosa is preserved. Can be done open, laparoscopic, or by a contemporary circumbilical incision. (Domino, Baldor, Golding, & Grimes, 2015, p. 1014)

Management/treatment Pharmacologic Atropine Lower success rate and longer duration than surgery. Surgical alternative for patients unsuitable or at high risk for surgery. (Domino, Baldor, Golding, & Grimes, 2015, p. 1014)

cOMPLICATIONS No long term morbidity. Duodenal perforation. No major difference between open vs. lap. pyloromyotomy, although laparoscopic approach has faster time back to full feeding & shorter hospital stay. (Domino, Baldor, Golding, & Grimes, 2015, p. 1014) Duodenal perforation is a known but uncommon surgical complication.

Follow up Postoperative monitoring including monitoring for pain, apnea, and emesis. Routine pediatric health maintenance thereafter. (Domino, Baldor, Golding, & Grimes, 2015, p. 1014)

Counseling/education Vomiting may continue for a few days after surgery. Not as significant as pre-op. Vomiting which continues more than 5 days after surgery should be investigated. Introduce feedings gradually. Prognosis after surgery is excellent. (Burns, Dunn, Brady, Starr, & Blosser, 2013, p. 980)

Consultation/referral Pediatric Gastroenterologist. Pediatric Surgeon.

Question #1 Pyloric Stenonosis is most commonly seen in? A) Females B) Males

Answer #1 B) Males Rationale: There are four times the number of male babies born with the condition as opposed to females.

Question #2 Clinical finding consistent with pyloric stenosis include: A) Bilious project vomiting B) Non-bilious projectile vomiting C) Weight gain D) Increase in bowel movements

Answer #2 B) Non-bilious projectile vomiting. Rationale: Gastric outflow is obstructed, which leads to gastric distention and vomiting, so babies are vomiting feedings soon after taking it in. Clinical findings also include weight loss and a decrease in bowel movements.

Question #3 True or false: Pyloric stenosis is familial. A) True B) False

Answer #3 A) True Rationale: The condition tends to be familial. There is a 5x increased risk with an affected 1st degree relative

Question #4 What is the study of choice used to diagnose pyloric stenosis? A) CT abdomen B) Upper GI series C) Abdominal US D) MRI abdomen

Answer #4 C) Abdominal US Rationale: Abdominal US is the study of choice to diagnose pyloric stenosis. Pyloric stenosis will show thickened and elongated pyloric muscle.

Question #5 Which group is pyloric stenosis seen in most commonly? A) Hispanic 1st born females B) Hispanic 1st born males C) Caucasian 1st born females D) Caucasian 1st born males

Answer #5 D) Caucasian 1st born males

Question #6 What is a late sign of pyloric stenosis? A) Dehydration B) “Olive-like” mass in middle upper or RUQ C) Epigastric distention D) Visible peristalsis after feeding

Answer #6 A) Dehydration Rationale: Pyloric stenosis that goes undiagnosed for some time can result in dehydration. Olive sign, epigastric distention, and visible gastric peristalsis after feeding are the first presentations of pyloric stenosis.

Question #7 True or false: Dehydration may cause metabolic abnormalities with pyloric stenosis. A) True B) False

Answer #7 A) True Rationale: Frequent vomiting seen with pyloric stenosis may lead to dehydration, which can lead to metabolic abnormalities.

Question #8 Name a pharmacologic intervention appropriate for treatment of pyloric stenosis. A) Zantac B) Omeprazole C) Atropine D) Amlodapine

Answer #8 C) Atropine Rationale: Although it has a lower success rate and longer duration of treatment, for patients who surgery is contraindicated or are high risk, Atropine may be used.

Question #9 True or false: Babies with pyloric stenosis may have blood tinged emesis. A) True B) False

Answer #9 A) True Rationale: Gastric irritation from frequent vomiting causes blood tinged emesis.

Question #10 When does pyloric stenosis typically first present? A) 9 months B) At birth C) 6 months D) 3-6 weeks

Answer #10 D) 3-6 weeks Rationale: Pyloric stenosis typically first presents at age 3-6 weeks. It rarely occurs in the newborn period or after 5 months of age.

references Burns, C., Dunn, A., Brady, M., Starr, N., & Blosser, C. (2013). Pediatric primary care (5th ed., p. 980). Philadelphia, PA: Elsevier. Domino, F., Baldor, R., Golding, J., & Grimes, J. (2015). The 5-minute clinical consult standard 2015 (23rd ed., p. 1014-1015). Philadelphia, PA: Wolters Kluwer Health. Singh, J., & Sinert, R. (n.d.). Pediatric Pyloric Stenosis . Retrieved September 29, 2014, from http://emedicine.medscape.com/article/803489-overview#a0104 Congenital adrenal hyperplasia. (n.d.). Retrieved September 29, 2014. Hope, W. (2013, March 4). Gastric Volvulus . Retrieved September 29, 2014. Bell, M., Ternberg, J., Keating, J., Moedjona, S., McAlister, W., & Shackelford, D. (1978, June 13). Prepyloric gastric entral web: a puzzling epidemic. Retrieved September 29, 2014.