What is Gastroesophageal Reflux in infants?
Most infants occasionally “spit up” or “throw up” after they eat. Some infants spit up or throw up so frequently that they are said to have gastroesophageal reflux. This term describes splashing or pushing of stomach contents backwards up into the esophagus, and sometimes, out the mouth. All of us have some reflux every day. Most of the time, reflux causes no problems or discomfort, and often, we are not even aware when it happens.
When a baby throws up after nearly every feeding and numerous times between feedings, parents often become concerned and they seek medical advice. They may be worried that there is something seriously wrong with their baby’s stomach or intestinal tract. They may be concerned that:
- there is an area of blockage or narrowing in their baby’s intestinal tract
- the baby is not keeping enough food down to grow
- the baby has an ulcer
- the baby is allergic to milk
Fortunately, in the vast majority of cases, none of these are true. Most of the time, reflux in infants and children is due to incoordination of the upper intestinal tract rather than to any distinct anatomic abnormality and as a result, almost all babies with gastroesophageal reflux will ultimately outgrow this problem!
Most children suffering from gastroesophageal reflux are otherwise normal and healthy. However, children who have developmental or neurological disabilities are more likely to suffer from gastroesophageal reflux than are children who are neurologically normal, and the symptoms of reflux in children with developmental disabilities are often more severe and/or more persistent. Often, parents of children with disabilities become worried that the frequent vomiting associated with GER may limit their child’s growth and development, or cause the child to aspirate and develop pneumonia or other respiratory symptoms.
Symptoms of GER:
Remember, we all have some gastroesophageal reflux. We only consider reflux abnormal when there is too much of it or there are unusual symptoms associated with it. Most of the time, we don’t feel much when we reflux, however sometimes when adults have gastroesophageal reflux, they complain of:
- a feeling of food getting stuck in their throat (the medical term for this is dysphagia)
recurrent or persistent hiccoughs
While we assume that young infants may have the same symptoms, we don’t know for sure. The most common symptoms that young infants seem to experience with gastroesophageal reflux are:
- frequent or recurrent vomiting
- heartburn, gas, or abdominal pain
Many other symptoms are sometimes blamed on gastroesophageal reflux, but much of the time, we really aren’t sure whether reflux actually causes them. Some less common problems seen in young infants that are may be blamed on gastroesophageal reflux include:
- colic or recurrent abdominal pain
- recurrent episodes of choking or gagging
- feeding problems
- poor growth
- unusual posturing such as wry-neck (torticollis) or arching (opisthotonus)
- recurrent episodes of wheezing or pneumonia
Colic, abdominal pain, and feeding difficulties and gastroesophageal reflux:
Older children and adults with chronic reflux sometimes complain of frequent heartburn, chest pain, or indigestion. Some adults experience frequent or recurrent hiccups or complain that food “gets stuck” in their throat (dysphagia). Most of these symptoms are thought to develop when the esophageal lining becomes inflamed or irritated by chronic or repeated exposure to gastric acid and gastric digestive juices (esophagitis).
While we often assume young infants experience similar symptoms with reflux, it is very difficult to know whether a baby’s irritability, difficulty sleeping, or feeding problems are caused by reflux. Thirty-six percent of infants experience daily episodes of hiccups, 17% cry for at least an hour each day, and 10% have at least one episode of arching each day so these behaviors are by no means specific for reflux. Nevertheless, there are reports of infants with feeding failure or feeding refusal, repeated arching (opisthotonus), or other unusual forms of posturing whose symptoms improve or resolve with treatment for reflux.
Very rarely, infants with chronic and/or severe reflux may develop erosive or bleeding esophagitis. This can result in blood being visible when the child vomits or spits up. If the esophagitis is extremely severe or it persists for a prolonged period of time, it is possible for esophageal scarring to develop. This is termed an esophageal stricture. It is very difficult to determine how many children with chronic reflux develop esophageal strictures, but they are clearly very rare. Among adults with chronic esophagitis, only three in 1000 will develop esophageal strictures over many years of follow-up.
Poor growth and gastroesophageal reflux:
It is extremely unusual for gastroesophageal reflux to impair or limit a child’s growth as long as an adequate number of calories are being provided. In most cases, poor growth in a child with gastroesophageal reflux occurs when a family unintentionally limits their child’s intake of calories. To try and lessen the vomiting, they dilute the formula with water or limit milk/formula intake and substituting water or Pedialyte®.
Respiratory symptoms and gastroesophageal reflux:
There is a long list of respiratory symptoms that may be associated with gastroesophageal reflux, however, it is often difficult to know whether the reflux causes the lung problems or the other way around. Since the windpipe (trachea) and the esophagus are very close together, many people have assumed that aspiration of refluxed stomach contents leads to respiratory symptoms.
Reflux of stomach contents up into the upper esophagus has been demonstrated in some patients with recurrent respiratory symptoms, however this appears to be very uncommon and is probably extemely rare among children who are neurologically normal.
While children with neurological abnormalities may aspirate refluxed stomach contents, more often, these children aspirate while they are eating. This is called laryngeal penetration and it occurs when swallow-breathe patterns are not well coordinated. Normally, with the initiation of a swallow, there is a pause in breathing and the larynx closes to protect the airway. In children who show no swallowing difficulties, it is reasonable to assume that these protective reflexes will function during an episode of gastroesophageal reflux.
There are reports describing children who suffer from chronic congestion and chronic hoarseness having gastroesophageal reflux. It is thought that aspiration of refluxed stomach contents causes inflammation and swelling of the upper airways and results in noisy breathing (stridor) or spasms of the vocal cords (laryngospasm). If evaluation of the upper airway demonstrates chronic inflammation, it is reasonable to consider GER as a potential source of the symptoms.
The role of GER in apnea (stopping breathing) and bradycardia (slowing of the heart rate) has been of great interest because of the potentially life-threatening nature of these symptoms. Although many studies have demonstrated that infants with apnea may have gastroesophageal reflux, there is usually little or no correlation between apneic episodes and reflux episodes. Instances in which apnea and GER have been directly associated in a cause-and-effect manner are extremely uncommon.
Both children and adults with chronic asthma have an increased incidence of gastroesophageal reflux. However, it is extremely difficult to know whether reflux causes asthma or asthma causes reflux. Chronic asthma may precipitate reflux since chronic coughing and increased respiratory efforts increase abdominal pressure which tends to force stomach contents upwards. Among children with chronic asthma, the overall incidence of gastroesophageal reflux has been reported to range between 46 and 75%. In one study, 82% of adult asthmatics had evidence of reflux!. Relatively few children with chronic asthma experience significant improvement in their asthma when they are treated for reflux so while reflux should be considered as a possible cause of uncontrolled chronic respiratory symptoms in children, it is important to remember that many of the trigger factors for wheezing also trigger gastroesophageal reflux.
In almost all cases, gastroesophageal reflux is caused by incoordination or immaturity of the upper part of the intestinal tract. Before we can understand why reflux occurs, we need to understand how the upper part of the intestinal tract works.
There are three main parts of the upper intestinal tract:
The esophagus is a long muscular tube connecting your mouth and your stomach. There are muscles at the top and bottom of the esophagus that control things coming and going, much like control valves. These muscles are called the upper and lower esophageal sphincters (pronounced sfink – ters).
The stomach is hollow and surrounded by two very thick layers of muscle. The stomach functions as a reservoir or holding tank for the food we eat. In children, when the stomach is empty, it is about the size of a fist, but it can get much bigger as you put things into it.
The duodenum is the uppermost part of the small intestine. The small intestine is a very long tube where food gets broken into very tiny “microscopic” particles and then absorbed into the blood.
How things work normally:
When things are working normally, after chewing your food, you swallow. When you swallow, you are pushing the food into the back of your throat and then down your esophagus. At the bottom of the esophagus is the lower esophageal sphincter. This muscle works to keep food in the stomach when the stomach is contracting or squeezing. When you swallow food, it doesn’t just fall down the esophagus, it is pushed down the esophagus towards the stomach. The esophagus squeezes in a coordinated fashion with the squeeze moving from the top of the esophagus downwards towards the stomach (this coordinated type of squeezing is called peristalsis). As the food gets down to the bottom of the esophagus, the lower esophageal sphincter opens to let the food pass into the stomach and then the sphincter muscle closes again. Every time we swallow food or saliva, our esophagus squeezes in this coordinated fashion and the lower esophageal sphincter temporarily opens.
Once food gets into the stomach, it is mixed with stomach acid and other digestive juices. The stomach works like a blender. It mixes food with acid and digestive juices and mashes the food into very tiny pieces. Once the food is completely mashed, the muscle at the bottom of the stomach called the pylorus opens and closes to very slowly dribble the food into the first part of the small intestine called the duodenum.
In the small intestine, the mashed food is broken into very tiny microscopic pieces by other digestive juices and then the “digested” food is absorbed . . . passed across the lining of the intestine and into the blood.
What happens with Gastroesophageal Reflux:
As you can see, this is a very complicated process. In children with gastroesophageal reflux, there is some incoordination of the upper intestinal tract that accounts for their problems. Most children with reflux are good eaters . . . in fact, many times they are guzzlers . . . when they are hungry, they cannot be put off. They often become quite frantic, screaming and clawing at their faces. Once they are fed, they tend to gulp down their milk or formula very quickly. They usually don’t choke or gag during feedings. This suggests they have no difficulty getting the food from their mouth to their esophagus!
Once the food is in their stomach, the stomach begins contracting – mashing the food and mixing it with acid and digestive juices. In children with reflux, out of the blue, the lower-esophageal sphincter opens so that as the stomach squeezes, there is nothing to keep the food in the stomach and so it comes back up the esophagus. This is gastroesophageal reflux! Sometimes, the food and acid come all the way up the esophagus and out the mouth and the child “spits up” or “vomits”. Other times, the food or acid may only come part way up. In you and I, this is what we call heartburn or indigestion.
Anything that increases the pressure in the stomach has a tendency to make reflux worse. This is why many infants with reflux will spit up when they are straining to pass a bowel movement or when they cough, sneeze, or laugh.
Since reflux usually takes place when the stomach is contracting normally, most of the time, when an infant “throws-up” or “spits-up” with reflux, they don’t have much pain or discomfort. In fact, many infants with reflux are not bothered at all by their reflux. They will be perfectly content immediately before they throw-up, and seem fine immediately afterwards too. Much of the time, it seems as if the baby isn’t aware of any problem before they throw-up! This is very different than when we vomit because we have an intestinal flu-virus or an intestinal blockage. With that type of vomiting, we feel sick beforehand. We become very nauseous, we start sweating, salivating, and swallowing. We do all sorts of things to prepare ourselves for the vomiting including running to the bathroom!
How does my doctor make a diagnosis of reflux?Most of the time, just hearing the parents’ story and seeing the child is enought to make the diagnosis, but sometimes testing may be recommended. The tests that are most commonly used to diagnose gastroesophageal reflux include:
- barium swallow or upper GI series
- technetium gastric emptying study
- pH probe
- endoscopy with biopsies
Barium swallow or Upper GI seriesThis is a special x-ray that allows doctors to follow food down the baby’s esophagus, through the stomach and into the first part of the small intestine. The baby is fed a chalky-white liquid called barium. A video x-ray machine follows the barium through the upper intestinal tract and lets doctors see if there are any abnormal twists, kinks or narrowings of the upper intestinal tract. This x-ray test does not, however, give doctors much information on how the intestine works when food is in it and therefore it is not a very reliable way of diagnosing gastroesophageal reflux. Many children with severe symptoms of gastroesophageal reflux will not demonstrate reflux on a barium swallow (poor sensitivity) and conversely, children who demonstrate reflux on a barium swallow have no symptoms of gastroesophageal reflux (poor specificity). Perhaps more important, the severity of reflux observed on a barium swallow does not help to predict the severity of symptoms of reflux nor does it help to predict the ultimate outcome. Less than 30% of adults with symptoms of chronic gastroesophgaeal reflux demonstrate reflux on a barium swallow and less than 30% of adults with esophagitis as a result of chronic gastroesophageal reflux will demonstrate reflux on a barium swallow.
Technetium reflux scanWith this test, the infant drinks milk mixed with technetium, a very weakly radioactive chemical, and then the technetium is followed through the intestinal tract using a particular type of camera. This test is helpful in determining whether some of the milk/technetium ends up in the lungs (aspiration). It may also be helpful in determining how long milk sits in an infants stomach.
pH ProbeWith this test, a small wire with an acid sensor is placed through the infants nose down to the bottom of the esophagus. The sensor can detect when acid from the stomach is “refluxed” into the esophagus. This information is generally recorded on a computer. Usually, the sensor is left in place between 12 and 24 hours. At the conclusion of the test, you are able to determine how often the infant “refluxes” acid into his or her esophagus and whether he or she has any symptoms when that occurs. The biggest problem with this test is that the severity of the reflux as measured by pH probe often doesn’t correlate with the severity of symptoms . . . that is, some of infants with very frequent vomiting will have normal pH probe studies. Perhaps more important, the severity of reflux measured by a pH probe does not help to predict the ultimate outcome. While pH probe analysis is abnormal in nearly 80% of infants with mild symptoms of reflux (i.e. occasional spitting and vomiting), one third of the infants with severe symptoms have a normal pH probe study! Moreover, less than 40% of infants with severe esophagitis due to chronic gastrophageal reflux will demonstrate abnormal pH probe studies. Perhaps the greatest potential value of pH probe analysis is in trying to correlate gastroesophageal reflux with unusual or persistent symptoms such as apnea, stridor, coughing or wheezing, choking, gagging, or unexplained irritability. If these symptoms occur frequently enough, a pH probe analysis can be performed to determine if these symptoms occur at the same time as episodes of acid reflux into the esophagus.
Endoscopy with biopsiesThis is the most invasive of all of our tests. With this procedure, a flexible endoscope with lights and lenses is passed down through the infant’s mouth into the esophagus, stomach, and duodenum. This allows the doctor to get a directly look at the esophagus, stomach, and duodenum and see if there is any irritation or inflammation present. In some children with gastroesophageal reflux, repeated exposure of the esophagus to stomach acid causes some inflammation (esophagitis). The greatest problem with this test is that most infants with symptoms of gastroesophageal reflux do not develop esophagitis (less than half of infants with severe symptoms of gastroesophageal reflux desmontrate esophagitis at endoscopy) and so a normal test does not necessary mean the child does not have reflux.
As you can see, none of these tests is perfect . . . they all have strengths and weaknesses and they each provide a different type of information. In most cases, the diagnosis of gastroesophageal reflux can be made clinically based on a careful history and physical examination. In children whose development is delayed or disordered, it is appropriate to consider gastroesophageal reflux when the child suffers from recurrent pneumonia or aspiration, is chronically irritable without any apparent explanation, or does not grow well despite receiving adequate numbers of calories. Diagnostic tests are primarily useful when trying to associate these types of unusual or severe symptoms with gastroesophageal reflux, but offer little information about the ultimate outcome or appropriate treatment strategies.
How do we treat GER ?
The most important thing to remember when treating gastroesophageal reflux is that in almost all cases, the problem will get better on its own! With that in mind, most of our treatments are geared towards lessening the symptoms of the reflux, not fixing it. Given enough time, the baby will fix the problem on his or her own.
If you think of gastroesophageal reflux as incoordination of the baby’s upper intestinal tract, then, as the baby’s overall coordination improves, the reflux will improve too. Most of the time, when the child is able to sit-up well without any assistance, the reflux starts to get better. This is usually around six months of age. Most of the time, when the baby is able to walk proficiently, the reflux tends to disappear. This is usually around twelve months of age.
Treatments for reflux can best by summarized in several broad categories:
- dietary treatments
- changing feeding schedules
Theoretically, the best position to but a baby with reflux in after meals is lying on their stomach with their head propped up about 30 degrees. Lying in this position causes the stomach to fall forward, closing the connection between the stomach and the esophagus. Remember, this is only theoretical! Same infants will not lie in this position without crying, and if the baby cries all the time, they fill up their stomach with air, grunt, and strain, which tends to make their reflux worse.
Perhaps more important than using the “best” position, is avoiding “bad” positions. In young infants who don’t have much control of their abdominal or chest muscles, when they are placed in an infant seat or swing, they tend to slump down. This increases the pressure in the their stomachs which tends to worsen their reflux. It is much better to lie them down or place them in a seat that reclines a bit than to have them slumped down.
While many parents and families attribute gastroesophageal reflux to sensitivities or allergies to milk or fomula, there is no convincing evidence to support this. While many infants will have less vomiting when they are switched from one type of milk to another, in most cases, this improvement only lasts two or three days. While there are certainly some infants who do better on one type of formula than another, most infants continue to vomit no matter what type of milk they are fed with (including breast milk).
Many parents are instructed to thicken their infants feedings with cereal as a way of lessening reflux. By thickening the feedings with cereal, the milk is physically heavier, and thus less likely to come back up. There are however, some problems with thickening feedings with cereal. It is not possible to thicken feedings if the baby is largely breast fed. Also, many infants with reflux are very vigorous or voracious feeders. When the milk is thickened with cereal, the baby has to suck harder to get the milk through the nipple. This may cause the baby to fill their stomach with air which can actually worsen the symptoms of reflux.
Many parents find that their babies keep solid foods down more effectively than liquids. This may simply be because solid foods are heavier and thus less likely to come back up, but also, solid foods are emptied out the stomach differently than liquids are. In any case, there is no evidence to suggest that feeding young infants solid foods with a spoon or from an infant feeder is harmful.
Changing Feeding Schedules
Parents are sometimes instructed to feed their babies smaller amounts more often with the idea that over-feeding tends to make reflux worse. Unfortunately, many babies with reflux are not satisfied with only one and a half or two ounces of milk, and they will cry for more. Again, when babies cries for extended periods, they fill their stomachs with air, they grunt, and they strain, all of which tend to make reflux worse.
While many different medications may be used to try and treat reflux, most of the medications fall into three groups:
- medications that break down or lessen intestinal gas
- medications that decrease or neutralize stomach acid
- medications that improve intestinal coordination
Medications that break down or lessen intestinal gas
Medications that decrease or neutralize stomach acid
Medcines that inhibit stomach acid secretion or production
- Tagamet® (cimetidine)
- Zantac® (ranitidine)
- Prilosec® (omeprazole)
- Prevacid® (lansoprazole)
It is assumed that decreasing the amount of stomach acid will lessen the symptoms of reflux. While this has clearly been shown in adults, very few studies have been published examining the effectiveness of these medicines in young children. In theory, these types of medications should be helpful to those babies who are having “heartburn” and nearly three fourths of parents report that their babies spit up or throw up less and seem to have less “heartburn” when they take them.
For the most part, medicines that decrease intestinal gas or neutralize stomach acid (antacids) are very safe. At high doses, Mylicon®, Maalox®, and Mylanta® may function as laxatives and cause some diarrhea. Chronic use of very high doses of Maalox® or Mylanta® may be associated with an increased risk of rickets (thinning of the bones).
Side effects from medications that inhibit the production of stomach acid are quite uncommon. A small number of children may develop some sleepiness when they take Zantac®, or Tagemet®. Tagamet® may can increase blood levels of certain other medicines including the blood thinner coumadin and the anti-seizure medicine Dilantin®.
Medications the improve intestinal coordination
- Reglan® (metoclopramide)
While Reglan® increases the pressure of the lower esophageal sphincter (LES) and helps that stomach to empty more quickly, in most infants, this medicine does not improve the symptoms of reflux. Rarely, Reglan® can cause frightening side effects. Young infants may develop dystonia (tenseness or stiffness of the muscles) and children with epilepsy appear to be at increased risk of having seizures when taking Reglan®.
Fortunately, it is exremely rare for children suffering from gastroesophageal reflux to require surgery. In those very few children who do require surgery, the most commonly performed operation is called Nissen fundoplication. With this operation, the top part of the stomach (the fundus) is wrapped around the bottom of the esophagus to create a collar. After the operation, every time the stomach contracts, the collar around the esophagus contracts preventing reflux.
This operation is very effective at eliminating gastroesophageal reflux with long-term success rates approaching 90%, however, some children may develop very disturbing and debilitating symptoms following fundoplication. The risks and benefits of surgery must therefore be weighed very carefully.