Pyloric stenosis - Clinicals, Diagnosis, and Management

Pediatric surgery

Clinicals - History

Fact Explanation
Non bilious projectile vomiting following a feed occurring at around 6 weeks of age. Due to pyloric muscle hypertrophy associated with clusters of tonic and phasic pyloric contractions beginning postnatally . Non bilious projectile vomiting following a feed occurring at around 6 weeks of age.
Due to pyloric muscle hypertrophy associated with clusters of tonic and phasic pyloric contractions beginning postnatally .
Blood stained vomitus. Due to gastric stasis and gastro-oesophageal reflux leading to superficial ulceration of the gastric and esophageal mucosa . Blood stained vomitus.
Due to gastric stasis and gastro-oesophageal reflux leading to superficial ulceration of the gastric and esophageal mucosa .
Poor weight gain, weight loss, decreased urinary output, lethargy, etc. These are features of dehydration and malnutrition which occur as a result of the gastric outlet obstruction and vomiting after each feed . Poor weight gain, weight loss, decreased urinary output, lethargy, etc.
These are features of dehydration and malnutrition which occur as a result of the gastric outlet obstruction and vomiting after each feed .
Jaundice. This maybe due to various associations of the condition such as prematurity and abnormal glucuronyl transferase activity as a result of starvation . Jaundice.
This maybe due to various associations of the condition such as prematurity and abnormal glucuronyl transferase activity as a result of starvation .
It is more common among first born males. Four times more likely to occur in first born male children. It is more common among first born males.
Four times more likely to occur in first born male children.

Clinicals - Examination

Fact Explanation
A firm, nontender, mobile and hard pylorus that is 1-2 cm in diameter (felt as an olive), present in the right upper quadrant at the lateral edge of the rectus abdominus muscle. Due to pyloric muscle hypertrophy . A firm, nontender, mobile and hard pylorus that is 1-2 cm in diameter (felt as an olive), present in the right upper quadrant at the lateral edge of the rectus abdominus muscle.
Due to pyloric muscle hypertrophy .
Visible gastric peristalsis. Strong peristaltic activity occurs in an effort to overcome the pyloric obstruction . Visible gastric peristalsis.
Strong peristaltic activity occurs in an effort to overcome the pyloric obstruction .
Depressed fontanelles, dry mucous membranes, poor skin turgor, etc. These are features of dehydration which occurs as a result of the vomiting of gastric contents . Depressed fontanelles, dry mucous membranes, poor skin turgor, etc.
These are features of dehydration which occurs as a result of the vomiting of gastric contents .
Anthropometric examination including length and weight of the infant. Malnutrition can occur as a result of the gastric outlet obstruction and vomiting after each feed . Anthropometric examination including length and weight of the infant.
Malnutrition can occur as a result of the gastric outlet obstruction and vomiting after each feed .

Investigations - Diagnosis

Fact Explanation
Thickened pyloric muscle on abdominal ultrasonography (thickness greater than 4 mm). Ultrasound is non-invasive, does not use ionising radiation, and reduces the need to
perform repeated clinical examinations .
Thickened pyloric muscle on abdominal ultrasonography (thickness greater than 4 mm).
Ultrasound is non-invasive, does not use ionising radiation, and reduces the need to
perform repeated clinical examinations .
The "shoulder sign" and "string sign" on a barium meal. These signs occur due to the compression of the duodenal bulb along with indentation of the gastric antrum (shoulder sign), and a narrow and elongated pylorus (string sign) . The "shoulder sign" and "string sign" on a barium meal.
These signs occur due to the compression of the duodenal bulb along with indentation of the gastric antrum (shoulder sign), and a narrow and elongated pylorus (string sign) .

Investigations - Management

Fact Explanation
Serum electrolyte levels and arterial blood gas analysis revealing a Hypochloremic, hypokalemic metabolic alkalosis. vomiting of gastric contents results in excessive loss of hydrogen chloride and potassium chloride. Also, diminished
secretion of pancreatic bicarbonate
into the gastrointestinal tract as a result of the inability of hydrogen ions entering the duodenum contributes to the alkalosis .
Serum electrolyte levels and arterial blood gas analysis revealing a Hypochloremic, hypokalemic metabolic alkalosis.
vomiting of gastric contents results in excessive loss of hydrogen chloride and potassium chloride. Also, diminished
secretion of pancreatic bicarbonate
into the gastrointestinal tract as a result of the inability of hydrogen ions entering the duodenum contributes to the alkalosis .
Elevated blood urea nitrogen levels and serum creatinine levels. The dehydration resulting from the vomiting of gastric contents would lead to reduced renal blood flow, and subsequent acute renal failure . Elevated blood urea nitrogen levels and serum creatinine levels.
The dehydration resulting from the vomiting of gastric contents would lead to reduced renal blood flow, and subsequent acute renal failure .
Elevated unconjugated bilirubin levels in blood. This maybe due to various associations of the condition such as prematurity and abnormal glucuronyl transferase activity as a result of starvation . Elevated unconjugated bilirubin levels in blood.
This maybe due to various associations of the condition such as prematurity and abnormal glucuronyl transferase activity as a result of starvation .

Management - Supportive

Fact Explanation
Immediate intravenous infusion of a fluid bolus (20 mL/kg) of crystalloids. To overcome the dehydration which occurs as a result of the vomiting of gastric contents . Immediate intravenous infusion of a fluid bolus (20 mL/kg) of crystalloids.
To overcome the dehydration which occurs as a result of the vomiting of gastric contents .
Maintenance of proper fluid and electrolyte balance. 5% dextrose in 0.25% or 0.33% sodium chloride with 2-4 mEq KCl per 100 mL replacement. Vomiting of gastric contents results in excessive loss of hydrogen chloride and potassium chloride . Maintenance of proper fluid and electrolyte balance. 5% dextrose in 0.25% or 0.33% sodium chloride with 2-4 mEq KCl per 100 mL replacement.
Vomiting of gastric contents results in excessive loss of hydrogen chloride and potassium chloride .

Management - Specific

Fact Explanation
Corrective surgery (treatment of choice). Ramstedt pyloromyotomy: the underlying antro-pyloric mass is split leaving the mucosal layer intact. It is curative for gastric outlet obstruction and the prognosis is excellent . Corrective surgery (treatment of choice). Ramstedt pyloromyotomy: the underlying antro-pyloric mass is split leaving the mucosal layer intact.
It is curative for gastric outlet obstruction and the prognosis is excellent .
Intravenous atropine injection of 0.01 mg/kg. clusters of tonic and phasic pyloric contractions are transiently abolished by atropine and transpyloric flow is improved . Intravenous atropine injection of 0.01 mg/kg.
clusters of tonic and phasic pyloric contractions are transiently abolished by atropine and transpyloric flow is improved .

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