I would like to credit the group that I worked with for two years on developing some evidence-based guidelines for reflux. They are a group of gastroenterologists and general pediatricians and epidemiologists. We spent several weeks looking through articles and at evidence on how to manage reflux. Most of our recommendations are based on expert opinion because there is no decent quality data out there

Reflux is defined as the passage of gastric contents into the esophagus. It is a normal physiological process and occurs throughout the day in healthy infants, children and adults.

If we look at children, we tend to recognize reflux more because they actually vomit when they reflux. Suzanne Nelson did an epidemiological study looking at the incidents of reflux in a general pediatric population. She simply asked the question, how many times a day does your child vomit? From 0-3 months of age, she found that 50% of children vomited once per day and 15% up to four times per day. Then it increases between 4-6 months, so that almost 70% of kids will vomit once a day. Take a look at what parents thought of this. For the first three months it is not a big problem. By 6 months of age, about 50% of the parents said that this reflux was a major problem.

Gastroesophageal Reflux Disease occurs when the gastric contents reflux into the esophagus or oral pharynx and produce symptoms. This can include recurrent vomiting with inadequate growth. Esophagitis can cause hematemesis, anemia, or pain. There are also airway symptoms, such as apnea or ALTEs, asthma, pneumonia, upper airway symptoms, hoarseness and laryngitis. There are also dental symptoms, such as otitis media and sinusitis.

What causes reflux? When stomach contents go up into the esophagus, you will have Gastroesophageal reflux by definition. You have a positive intraabdominal pressure and a negative intrathoracic pressure tending to help push stuff up. On the lower esophageal sphincter, the mechanics of the sphincter are much better understood than they were 10 years ago. Most people used to think reflux was due to the lower esophageal sphincter being lax or having a low pressure. But in people with reflux, the lower esophageal sphincter pressure is exactly the same as it is in the general population, about 95%. There are rare people that actually have a low sphincter pressure. In infants that are refluxing, it is exactly the same. Reflux occurs during what are called transient lower esophageal sphincter relaxations, which are brief periods where the muscle relaxes. The major reason it is relaxing is to allow the stomach to vent. It is the burp mechanism, so that when you distend the stomach, the lower esophageal sphincter relaxes. As you inspire, your abdominal pressure increases, intrathoracic pressure decreases, and the muscle contracts right around the lower esophageal sphincter region further enhancing the sphincter barrier. Finally, there is a little segment of interabdominal esophagus, below the diaphragm, above the stomach. If you strain, you will tend to squeeze down on that segment of esophagus, again creating a barrier when you have those differences in pressure. Once you reflux, you have to clear the acid. This is the defect that allows Esophagitis to occur. If you do not clear the acid, the acid will sit there for a long time, and you will end up with Esophagitis which is impaired esophageal clearance. The mechanism of esophageal clearance occurs in adults. When you are upright and tend to have gravity push back down into the stomach, there is the peristaltic wave. There is also a series of swallows of saliva, and by buffering the saliva, the saliva actually comes down and accomplishes a final buffering after we have an episode of reflux. Children have very bad esophageal or Esophagitis disease because they do not swallow and are usually drooling all the time with neurological disease. Those are the children we see have the worst Esophagitis. There are probably some mucosal defense mechanisms in the esophagus, like bicarbonate secretions in mucous, that helps prevent disease. Once you reflux, it goes up into your esophagus, and in some of us, it causes problems. Esophageal acidification can cause vagal reflexes that actually cause bronchospasm. In addition, you can have reflux come up, and if it distends the upper esophagus, it will then open the upper esophageal sphincter and the refluxate will go into the mouth. In a normal infant this is not a big deal, they just vomit it out and then reswallow. You can have impaired airway protective mechanisms and that allows acid to get down into the airway. This can cause chemical damage from refluxate or it can cause problems with the larynx.

This case is typical four month old child with multiple episodes of reflux, who has vomited maybe 15 times a day since about three weeks of age. The child has effortless and postprandially, normal growth and development, no pain or hematemesis, and the physical examination is entirely normal. Do a physical examination. If they do not have bilious or forceful vomiting, no hematemesis or hematakesia, no vomiting or diarrhea, no abdominal tenderness or distension, no fever, lethargy, hepatosplenomegaly, microencephaly or microcephaly seizures, then do not be worried about this child yet. Signs of GERD, or complications from GER could be poor weight gain, excessive crying, feeding problems or respiratory problems such as wheezing, stridor or recurrent pneumonia. If there are none of those, then you have an infant with what we label uncomplicated GER, with no D. In an infant with recurrent vomiting, a thorough history physical examination is sufficient to allow the clinician to establish a diagnosis of uncomplicated GER. Further testing and a referral to a pediatric gastroenterologist are not necessary.