The vomiting is often described as non-bile stained ("non bilious") and "projectile vomiting", because it is more forceful than the usual spitting up (gastroesophageal reflux) seen at this age. Some infants present with poor feeding and weight loss but others demonstrate normal weight gain. Dehydration may occur which causes a baby to cry without having tears and to produce less wet or dirty diapers due to not urinating for hours or for a few days. Symptoms usually begin between 3 and 12 weeks of age. Findings include epigastric fullness with visible peristalsis in the upper abdomen from the infants left to right. Constant hunger, belching, and colic are other possible signs that the baby is unable to eat properly. Cause
Rarely, infantile pyloric stenosis can occur as an autosomal dominant condition. It is uncertain whether it is a congenital anatomic narrowing or a functional hypertrophy of the pyloric sphincter muscle. Pathophysiology
The gastric outlet obstruction due to the hypertrophic pylorus impairs emptying of gastric contents into the duodenum. As a consequence, all ingested food and gastric secretions can only exit via vomiting, which can be of a projectile nature. While the exact cause of the hypertrophy remains unknown, one study suggested that neonatal hyperacidity may be involved in the pathogenesis. This physiological explanation for the development of clinical pyloric stenosis at around 4 weeks and its spontaneous long term cure without surgery if treated conservatively, has recently been further reviewed.Persistent vomiting results in loss of stomach acid (hydrochloric acid).
Therefore, the baby must be initially stabilized by correcting the dehydration and the abnormally high blood pH seen in combination with low chloride levels with IV fluids. This can usually be accomplished in about 24–48 hours.Intravenous and oral atropine may be used to treat pyloric stenosis. It has a success rate of 85-89% compared to nearly 100% for pyloromyotomy, however it requires prolonged hospitalization, skilled nursing and careful follow up during treatment. It might be an alternative to surgery in children who have contraindications for anesthesia or surgery, or in children whose parents do not want surgery. Surgery
The definitive treatment of pyloric stenosis is with surgical pyloromyotomy known as Ramstedts procedure (dividing the muscle of the pylorus to open up the gastric outlet). This surgery can be done through a single incision (usually 3–4 cm long) or laparoscopically (through several tiny incisions), depending on the surgeons experience and preference.Today, the laparoscopic technique has largely supplanted the traditional open repairs which involved either a tiny circular incision around the navel or the Ramstedt procedure. Compared to the older open techniques, the complication rate is equivalent, except for a markedly lower risk of wound infection. This is now considered the standard of care at the majority of childrens hospitals across the US, although some surgeons still perform the open technique. Following repair, the small 3mm incisions are hard to see. The vertical incision, pictured and listed above, is no longer usually required, though many incisions have been horizontal in the past years.