​Kembara Xtra - Medicine - Pyloric Stenosis

​Kembara Xtra - Medicine - Pyloric Stenosis 
Infantile hypertrophic pyloric stenosis (IHPS) is the medical term for the acquired narrowing of the pyloric canal caused by increasing pyloric muscle hypertrophy that causes obstruction.


Epidemiology 
The most common condition requiring surgical intervention in the first year of life; Onset almost always between 2 and 12 weeks of age; Highest incidence found in first-born infants; May be more common in bottle-fed infants; Recent decline in incidence has been reported in a number of countries.
● Male is more common than female (4 to 5:1) Incidence
2 to 5 per 1,000 Caucasian infants; less frequently in Asian and African American infants Prevalence
The national prevalence level is 0.5 to 4.21:1,000 live births, or 1 to 2:1,000 babies.

Pathophysiology and Etiology 

Hypertrophy results from abnormal pyloric muscular relaxation.
The actual etiology is unknown, but numerous genetic and environmental variables have been implicated. stomach outflow is restricted, causing stomach distension and strong projectile postprandial vomiting.
Formula feeding may result in increased serum levels associated with pylorospasm, raising rates of pyloric stenosis. Breast milk may mediate pyloric relaxation and promote stomach emptying, protecting from pyloric stenosis.


Genetics
There is a relationship to chromosomes 3, 5, 11, and 19 according to recent studies.

Risk Elements 
Premature delivery is NOT a risk factor. Strong family aggregation and >80% heritability 5 times increased risk with affected first-degree relative.
Formula feeding increases risk. Perinatal risk factors include C-section and first birth. Multiple gestation - 200-fold increased risk if monozygotic twin affected - 20-fold increased risk if dizygotic twin affected. Maternal white ethnicity. Perinatal alcohol and cigarette use. Postnatal macrolide antibiotics, especially erythromycin, may potentially cause sustained contraction of pyloric muscle.

Prevention 

It seems protective to breastfeed.

Accompanying Conditions 

Approximately 4–7% of newborns with pyloric stenosis have concomitant abnormalities.
 Inguinal and hiatal hernias (most frequent) The following rare related anomalies are listed: - Esophageal atresia - Congenital heart disease
The tracheoesophageal fistula
- Renal irregularities
- Trisomy 18 and the Turner syndrome
- The Cornelia de Lange condition
- The Smith-Lemli-Opitz condition

Emesis may turn bloody due to stomach irritation. Diagnosis Nonbilious projectile vomiting after feeding, increasing in frequency and severity.
Excessive sobbing, poor nutrition-related hunger, decreased bowel movements, weight loss, and a median symptom duration of 10 days.

clinical assessment 

Use of ultrasound (US) has facilitated earlier diagnosis, reducing the "olive-like" mass finding to 14% of patients who present with the classic triad of nonbilious vomiting, visible peristalsis, and a palpable olive. Epigastric distention Visible gastric peristalsis after feeding Late signs: dehydration, weight loss Rarely, jaundice when starvation causes decreased glucuronyl tranferase.

Differential Diagnosis: Pylorospasm, Gastric Volvulus, Antral or Gastric Web, Neonatal Intestinal Obstruction, Hiatal Hernia, Inexperienced or Inappropriate Feeding, GERD, Gastritis, Congenital Adrenal Hyperplasia, Salt-wasting

Laboratory Results 

Due to early detection and care, metabolic abnormalities are infrequent and late findings.
 If vomiting persists for a while, check electrolytes: metabolic alkalosis, hypokalemia, and hypochloremia  Rarely, elevated levels of unconjugated bilirubin In the face of hypokalemic alkalosis, paradoxical aciduria occurs when the renal tubules secrete hydrogen to preserve potassium.

Initial examinations (lab, imaging)
Pyloric US is the preferred study.
The pyloric muscle is enlarged and lengthened on the US, and the mucosa is redundant. 3-mm pyloric muscle thickness, 15-mm pyloric length, 11-mm pyloric width, and 12-mL pyloric volume are the pathologic limits; muscle thickness is the determining factor. Although these measurements are still diagnostic, they might rule out younger, smaller infants (less than three weeks old) who can be clinically diagnosed.
Upper GI series: if history, examination, and US are inconclusive, it may be employed in rare cases. Strong contractions of the stomach; a string of contrast material encircling the pyloric canal; and parallel lines of barium in the small channel divided by mucosa (also known as the "double-tract sign" or "railroad track sign") 

Pyloric muscle concentration hypertrophy: test interpretation

Prior to surgery, treat dehydration and alkalosis.
 Antibiotics given intravenously before to surgery (cefazolin 30 mg/kg or clindamycin 10 mg/kg) to prevent infection  Preoperative NG tubes are typically not necessary 

First Line of Medicine
Surgery can be replaced medically with atropine given intravenously or orally.
The recommended dosage of atropine is 0.05 mg/kg/day for oral atropine and is increased to a maximum of 0.1 mg/kg/day for IV atropine. When anesthesia or surgery is not an option, the dosage is 0.1 mg/kg/day for IV atropine and is increased by 0.01 mg/kg/day until vomiting stops. At that point, the oral atropine dosage is doubled. Vomiting typically stops within 7 days. 

Surgical Techniques 
Ramstedt pyloromyotomy is effective treatment. With the mucosa beneath the muscle preserved, the full length of the hypertrophied muscle is separated.
 Traditional right upper quadrant transverse incisions, more modern circumumbilical incisions, and laparoscopic procedures are all surgical options.
Less postoperative discomfort, quicker hospital stays, quicker postoperative recovery, lower complication rates, enhanced cosmesis, and the ability to be conducted without an increase in complications or operating time are all benefits of the laparoscopic technique.

Admission 
Quick intervention to prevent malnutrition and dehydration
 Resolve electrolyte and acid-base imbalances. Surgery should be postponed until metabolic imbalances are resolved.
Patients need pre- and postoperative apnea monitoring because they have a propensity to compensate for their metabolic alkalosis with respiratory acidosis (apnea). They also need IV fluids to treat dehydration and metabolic abnormalities. Use D5 1/2NS and 20 mEq of KCl for baby resuscitation that works well.


Following surgery, when 2 to 3 complete feeds are tolerated, patients are discharged.
Patient monitoring includes checking for pain, emesis, and apnea after surgery as well as routine pediatric health maintenance.
 If considerable emesis persists after 1 to 2 weeks, upper GI tests are required to rule out a duodenal leak or an incomplete pyloromyotomy.


Diet 

Adlib feedings are advised following pyloromyotomy because they shorten hospital stays.
The timing of the first meal is not important, however early feeding is linked to a higher risk of emesis without affecting the length of stay.


Patient Education Inform caregivers about postoperative emesis, infection signs and symptoms, and hydration assessment.


Surgery is curative in nature.

Complications include: delayed feeding due to postoperative vomiting; dehydration; failure to thrive; jaundice; chronic abdominal pain and pain-associated functional GI disorders following surgery; incomplete pyloromyotomy; mucosal perforation; wound infections; serosal tear; and subcutaneous emphysema. Complication rates range from 4.6 to 12% (2).[C]
RESOURCES 1.

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