Pediatric Feeding Disorders
Pediatric dysphagia has grown clinically over the past 15 years, along with the inclusion of speech – language pathologists in their diagnosis and treatment of the disorder. The incidence of swallowing disorders has been increasing partly because of the rise in the enhancement of technology, which work to save premature infants lives and/or those who are born with life threatening conditions. Gilger, Boyle, Sondheimer and Colletti (1997) define swallowing as “a complex process initiated by the voluntary ingestion of food and followed by the involuntary or automatic actions of the oropharynx and the esophagus” (p. 616). Barbara Sonies (1997) defines dysphagia as “difficulty [in] moving food from the mouth to the stomach and encompasses impaired airway protection and problems with secretion management” (p. 32). Infants and children with feeding and swallowing disorders are a diverse population ranging from premature infants to fully grown adolescents and it’s not particular to culture or race. Swallowing disorders are rarely isolated cases and are usually part of a larger problem that’s already in existence, an etiology. These disorders may be caused by various central nervous system damage or disorders, respiratory disorders, psychological or gastrointestinal/gastroesphogeal tract disorders. This paper will focus on the effect that gastroesophageal complications has on dysphagia in pediatric patients.
Normal Anatomy and Physiology Swallowing occurs with the timing and coordination of many different parts of the body. A dysfunction in any stage of the normal development, can impact feeding and drinking, and the systems involved which could result in dysphagia in any part of the anatomy. To understand dysfunction, it is extremely important to have a full grasp of the anatomy and the stages of development in a normally functioning child. Hall (2001) points out “newborn infants with intact anatomy and neurologic function most often quickly become efficient feeders” (Hall p. 8). There are four phases of swallowing that humans must endure to be successful in swallowing, and they are: the oral preparatory phase, oral transit phase, pharyngeal phase and the esophageal phase. However, an infant's anatomy is very different from an adults' and it is extremely important to be aware of this during an evaluation and treatment. Arvedson & Rogers (1993) report that “a disruption in anyone of these processes is likely to result in malnutrition, poor growth, delayed development, and/or loss of general health and well being” (p. 204).
The oral preparatory phase is a voluntary process where the food is wanted, taken into the oral cavity, and then masticated. The mastication serves to take the food and manipulate it into a cohesive bolus with the help of salivation, to prepare the food ingested for the remaining phases of the swallow (Drumright, King & Seikel p. 359).
The oral transit phase propels the bolus from the anterior portion of the tongue to the posterior and into the pharynx. The swallowing reflexes are then triggered when the bolus contacts the anterior faucial pillars. Once it reaches the anterior faucial pillars, the process is no longer voluntary and the third process of swallowing; the pharyngeal phase, is initiated. Arvedson & Rogers (1993) note that this point of the swallow could first be identified in the 10th to 11th weeks of fetal development (p. 204). The involuntary reflexes of the swallow that transpire at the pharyngeal phase trigger a number of physiological activities that occur simultaneously to prepare the system to accept the bolus and protect the places that we do not want the bolus to enter. First, the velum raises and retracts to completely close the velopharyngeal port in order to prevent material from entering the nasal cavity. The hyoid and larynx are moved up and forward contributing to the closure of the vocal folds in a bottom up fashion for the purpose of protecting the airway from the bolus. Any food or liquid that can get through the airway will result in aspiration. This bottom up closure sequencing acts as the last line of defense. The bottom seals off first, so if material does get through, a cough can squeeze it out, instead of entering the trachea and lungs. The movement of the hyoid and larynx also pulls the esophagus open and relaxes the upper esophageal sphincter (UES). This prepares the UES to receive the bolus, and allow it to enter the esophagus. At the end of the pharyngeal phase, breathing is reinitiated, which means that the vocal folds return to the abducted position. (Drumright, King & Seikel p. 361 - 364).
Compared to an older child, newborns have smaller oral and pharyngeal cavities. Newborns also have smaller mandibles along with fat pads made of adipose tissue in their buccal cavity, which allows their tongue to fill their mouth. Hall (2001) suggests, “this tissue provides sucking stability” (p. 16). The tissue begins to slowly disappear at around 4 to 6 months old. The larynx is higher in the neck for the newborn compared to older children, which places it in closer proximity to the tongue, soft palate, and pharynx. The closeness of these structures makes it tough, but not impossible, for aspiration to take place. As children grow older, these structures move back and downward, therefore develop a longer pharynx, which enables breathing and swallowing to work together.
Once the bolus reaches the esophagus through the cricopharyngeal muscle, the esophageal phase, which is the fourth and final stage of swallowing, is commenced. The esophagus is a tube composed of three layers that are epithelium, laminae propria, and muscularic mucosae, which allows the system to be limp. A newborns esophagus is about 8 – 10 cm. long, and it begins at the C4 to C6 and ends at C9. Once bolus enters the esophagus, it is carried to the stomach by a mixture of forces; normally 2 peristaltic waves and gravity. The bolus then leaves the esophagus through contraction of the lower esophageal sphincter (LES), and enters the stomach. The LES relaxes for a brief moment during deglutition, which allows the swallowed food to enter the stomach. The pressure differences created by the movement of the LES prevents reflux. While the bolus is in the stomach, acids and other fluids partially digest it, and then it continues on its path to the duodenum; the beginning of the small intestines. Delay in gastric emptying, which is a frequent occurrence for children, has been linked to the number of spontaneous LES relaxations and increases the possibility of GER by increasing the time for reflux to occur. (Hall, pgs. 18 & 24)
Normal feeding development begins with the suckling pattern by the 18th or 24th week and continues until about 6 months of age. The suckling pattern is then substituted with non-nutritive sucking and nutritive sucking, which is concurrent with the commencement of transitioning to spoon feeding. Should the child not reach the sucking pattern at or around 6 months of age, it could lead to long-term aversion of solid food or textures for that child. (Arvedson & Rogers pg. 204)
Hall states that “Motor development is the primary basis on which children learn to adapt, interact, and manage their environment” (p.12). Infants gain motor control in a head to toe, inward outward fashion. Once the child is productive in hand to mouth coordination that indicates that the child is ready to feed him or herself. At 9 months of age, a child should be able to sit by themselves, which is a sign of good trunk, and head control which is essential to the child’s ability to swallow thicker foods. All developmental milestones are simply a guideline and individual variation should always be considered.
ETIOLOGIES AND THEIR SYMPTOMS
A healthy gastrointestinal system impacts our craving to eat and the way we eat. Its function is to receive food, absorb fluids and nutrients necessary to prevent malnourishment, and discard the unwanted in the form of urine or stool. The GI system plays a major role in the passage of the food through the digestive system so a dysfunctional GI system can therefore negatively influence the desire to eat and result in malnutrition and poor growth. The management plan and diagnosis for any feeding disorder is usually dependant on its etiology. Arvedson & Rogers divide the etiologies into two categories; acute and chronic disorders. Chronic disorders are further subdivided into static or progressive. Some dysfunctions of the GI tract can be structural or motility based, or there might be an imbalance of acid or hormones. Below some of those disorders will be described. (Klein & Morris p. 555)
Klein & Morris (2000) report “when the series of upper channels and valves carrying food from the mouth to the stomach does not work well, aspiration becomes a high risk for oral feeding” (p.106). Though it is the reflux of acidic gastrointestinal contents that aspirate into the lungs which causes the most damage. The most common physiological limit is gastroesophageal reflux (GER), which is described as stomach contents that reflux back up into the esophagus, or at the pharyngeal level. North American Society for Pediatric Gastroenterology and Nutrition define Gastroesophageal reflux disease (GERD) as “having symptoms or problems with GER” (p. s2). Both are common tribulations in children and most people experience reflux every once in a while. Most infants spit up or vomit once a day as a normal part of the development of their GI system, but it usually has little effect on their eating and they tend to outgrow those vomiting occurrences between 8 and 12 months of age as the GI system grows and the infant increases it’s postural control. It is when the chronic reflux symptom of vomiting increase to more than once a day, and it being of large volume, that cause changes in the child’s appetite, health and development, that GERD is diagnosed and treated accordingly. Tube feedings increase the probability of GER occurring due to the positioning of the tube and the influence it has on stomach emptying.
It is difficult to identify swallowing disorders in infants and young children, because they mostly do not have the ability to communicate yet, and therefore are unable to complain about their discomforts or pains. Therefore, it’s very important that parents be aware of and watch out for signs of anything out of the ordinary. Symptoms of GERD can vary from person to person. A child does not need to display all of the symptoms to be diagnosed with GERD. It is important to look at the whole picture, as there can be a number of various causes for these symptoms. (Klein & Morris p.564)
Some common symptoms of GERD are cough, hoarseness or chronic aspiration due to refluxed material that can irritate the larynx and upper respiratory system. Other symptoms of GERD are vomiting, weight loss or poor weight gain, irritability during or after feeding, retching, heartburn or chest pain, dysphagia or feeding refusal, wheezing or stridor, and abnormal neck posturing. Another manifestation of GER is frequent swallowing with facial grimacing. A child may grimace because they figure out that saliva and swallowing, paired with peristalsis neutralizes the acidity of the reflux in the esophagus. Esophagitis occurs because of acid that stays in the esophagus, and in turn causes the esophagus to inflame, which causes symptoms ranging from mild nauseousness, gagging, irritability, heartburn to severe pain or the development of strictures. Esophageal strictures are a narrowing of the esophagus and can be either acquired or congenital resulting from acid damage from gastroesophageal reflux. (Klein & Morris p. 102)
Esophageal atresia (EA) is when the esophagus isn’t connected to the stomach as it should be. EA is usually identified at birth and must be treated by surgical reconstruction to reconnect the tubes properly before the child can eat orally. Children with this pathology sometimes also have tracheo-esophageal fistula, or TEF, which erroneously connects the trachea and the esophagus and hinders the natural separation of the two tubes for breathing and eating. There are variations of EA and TEF, along with many feeding complications due to surgical intervention for both conditions. (Klein & Morris p.103)
Achalasia is an esophageal dysmotility where the pressure of the LES is increased which inhibits the LES to not relax after swallowing. In turn, the esophagus elongates to support the bolus because the opening of the LES is smaller and obstructs the bolus from moving to the stomach. Manifestations of achalasia may include vomiting, difficulty in swallowing solids or liquids, weight loss, painful swallowing, recurrent pneumonia, and a feeling of foods getting stuck in your GI system. (Klein & Morris pgs. 107 – 108)
Should the lower end of the stomach be blocked in anyway, it could lead to delayed gastric emptying which can contribute to gastroesophageal reflux and projectile vomiting. Some causes of delayed gastric emptying are food sensitivities and allergies, which can contribute to GER, or can be caused by an ulcer, irritation, or growth in the stomach near the pylorus sphincter. (Klein & Morris p. 108)
Effective prevention of a gastrointestinal problem includes early detection and intervention. The best approach is with a multidisciplinary team consisting of a physician, nurse, nutritionist, occupational therapist, and a SLP. The diagnosis procedure should consist of the following:
- The SLP should take a concise history intake consisting of family
- Developmental, feeding, social
- Speech/language/cognitive difficulties
- Birth and medical
- Surgical history
- History of weight gain
- There should be a physical examination
- oral motor/feeding examination
- in some cases instrumental exams
(Arvedson & Rogers p.211 – 216)
Arvedson & Rogers (1993) suggest that “even in these days of high technology and many diagnostic studies, the case history frequently is the most important and enlightening part of an assessment.” (p. 213) The clinician should help the parent or caregiver be able to summarize their concerns regarding their child. The clinician might ask a question that the parent had never considered to be of any importance, and it very well could be. In obtaining the history, there should be questions that can indicate the age of the child at onset, and whether the condition is static or progressive. Developmental history is also an essential part of the diagnostic procedure. Newman (2001) states that “Information on development is a crucial part of the history intake because it is a reflection of the underlying disorder” (p. 7). Should there be any noteworthy delays in development, they should be addressed before the assessment and management of feeding and swallowing disorders takes place. When designing a questionnaire specific to developmental history, the SLP should consider a general description of the child’s communication skills, including if at all possible, when those milestones were met, feeding skills and/or difficulties, visual – problem solving abilities to show their cognitive skills, social and adaptive levels of functioning, gross and fine motor skills, again when, if at all possible to recall, and descriptions of the child’s temperament and general behavior.
As stated earlier, swallowing disorders are rarely isolated cases and are usually seen as part of a larger problem that already exists, an etiology. Therefore, a thorough and precise review of the child’s health is required prior to diagnosis and management of feeding abnormalities. Identifying children who are at risk is a major role for the speech language pathologist. It does happen that the swallowing disorder is the first sign of a problem in a child. Therefore, it is extremely important that the SLP know that there are various etiologies that can cause dysphagia. The SLP should immediately refer the child to the correct medical specialist. (Newman p. 6)
- The physical examination should consist of a neurodevelopment examination, airway assessment, gastrointestinal assessment, and an oral-motor feeding examination consisting of pre-feeding and actual feeding. (Arvedson & Rogers pgs. 214 – 215)
- The neurodevelopment examination “observes state regulations, resting posture, muscle tone, and quality of spontaneous movements” (Arvedson & Rogers p. 214) before and during oral feedings. This can take place via observation. The clinician should cautiously observe the child’s transitions from sleep, when quietly awake and crying, as those states can be fairly dysfunctional in a child who possesses Central Nervous System injuries.
- The child’s airway should be examined with a routine respiratory examination. Should there be a need for further radiologic evaluation, there are many techniques to choose from including plain anteroposterior (PA) and lateral radiographs of the airway, chest x-ray, barium esophagram, and/or a fast CT analysis. (Arvedson & Rogers p.214)
- The pre-feeding examination should also be done primarily through observations, noting any deviations from normal. Arvedson & Rogers (1993) suggest the following checklist may be a helpful guide when observing pre-feeding:
- parent-child interactions,
- positioning as well as posture and movement patterns
- respiratory patterns including rate of breathing and effort
- affect, temperament, and overall responsiveness
- evel of alertness
- responses to sensory stimulation
- ability to self-calm and self-regulate
Food and/or liquid should not be introduced until there is a complete assessment of the child’s oral structures and function. This part of the evaluation should include:
- lip and jaw positioning at rest noting any drooling
- palatal shape, at rest and movement patterns
- oral reflexes, particularly noting persistent primitive reflexes
- nonnutritive sucking in infants
- teeth and laryngeal function which is done by observing voice quality.
A child with a gurgly voice quality, is a sign of possible aspiration. The SLP should observe the face to assess functioning of the Cranial Nerves V Trigeminal-Mandibular Branch and VII Facial. The Cranial Nerve IX Glossopharyngeal should be looked at by observing the velum at rest and when active. The therapist should observe the Cranial Nerve X Vagus by observing the child’s voice quality and examine the strength of the child’s glottal closure. To assess damage of the Cranial Nerve X, observe the feeding/swallow assessment, as that’s when it should be noticeable. Finally, damage to the Cranial Nerve XII Hypoglossal is evaluated by observing the tongue at rest and in several other different positions. (Hall pgs. 92 – 93)
The feeding evaluation only takes place after the child is considered to have no respiratory or cardiac problems. To determine whether or not the study should be executed is based on if it will assist in the diagnosis or how the disorder is handled. Hall (2001) reports some “symptoms that indicate the need for clinical feeding assessment are failure to thrive or weight loss, sudden change in feeding, behavioral changes during or after feedings, frequent vomiting, [if] the bottle feeding lasts more than 30 minutes, weak dysfunctional suck and/or suspected neurological problems, coughing or choking during eating [and a] change in physiological state during or after feeding” (p. 84). A videofluoroscopic swallow study (VFSS), also known as the modified barium swallow, is the most optimal and preferred test for children. The VFSS provides a clear view of the pharyngeal phase of swallowing on that child offering the most sufficient information about the physical swallow.
Klein & Morris (2001) suggest that “an upper GI series is the first study that is usually chosen to do” (Morris and Klein p. 565). They then list the following reasons in explanation. The study is noninvasive, and should the child exhibit a GER occurrence during the study, the height and the time it continued on for can be documented. The many authors of the North American Society for Pediatric Gastroenterology and nutrition suggest that the upper GI series is not useful at all because there can be high false positives and false negatives. Therefore the information received in the GI series must be compared with the patient’s history and if GER is suspected, further testing will probably be needed.
An upper endoscopy gives a direct view of the esophageal tissue, which enables the physician to see esophagitis inflammation and take biopsies if needed. (North American Society For Pediatric Gastroenterology and Nutrition)
Other instrumental tests are manometry, a scintigraphy or technetium scan. Esophageal manometry provides an accurate dimension of esophageal contraction and is performed after the upper endoscopy of the esophagus eliminates any structural or other causes of the esophageal not working correctly. When performing manometry on a child as compared to an adult many anatomic and behavioral differences must be considered between the two ages. Manometry is best carried out without sedation, though in many children, sedation is necessary. Manometry is a beneficial tool when looking to evaluate nonstructural deviations of the esophagus such as achalasia, disorders of connective tissue, or to determine the site of the sphincters for esophageal pH monitoring. (Gilger, M.A., Boyle, J.T., Sondheimer, J.M. & Colletti, R.B. pgs. 617 - 618)
The PH probe is considered the best in GI testing as it is utilized to specifically diagnose GER, though it cannot detect reflux associated with meals and post-meals. The pH probe is also helpful in assessing the adequacy of therapy in patients who do not respond to treatments with anti-acids. (Hall p.78)
There are positives and negatives to each test, so it is necessary to run different tests and then match that information with all of the patient’s personal information gathered beforehand, before determining treatment options. The family needs to be heavily involved with all aspects of treatment. Hall (2001) declared that “Adequate nutrition/hydration and developing age-appropriate feeding skills are the goals of dysphagia therapy” (p.120), along with educating, training and working with the child’s caregivers. Unless the situation is life threatening, conservative management should be attempted before considering surgery especially because this surgery is preferred for children over the age of 18.
The first critical decision of the multidisciplinary team is to decide if a feeding tube is needed or not. There are many different types of tubes to choose from and they all come with advantages and disadvantages. Orogastric Tubes are used for short term nutritional support in premature infants and it eliminates the risk for potential blocking of the nasal cavity. Nasogastric Tubes are also used for short term use. Nasoduodenal Tubes are used when reflux is a problem. Nasojejunal Tubes are used for long term nutrition. Gastrostomy Tubes, or G Tubes are also used for more long term feeding issues, but has been shown to cause reflux episodes. Jejunostomy Tubes or J Tubes, on the other hand, are not as likely to cause reflux. The last tube option is the Gastrostomy – Jejunostomy Tube or G-J Tube, which is more invasive, allows for removal of stomach contents and the nutrition is delivered directly to the jejunum, bypassing the entire GI tract. Many complications can result from the placement of a feeding tube; therefore consideration of the advantages must be weighed against the disadvantages for each child’s situation. (Hall pgs. 39 – 40)
Treating GER can be as simple as making certain lifestyle changes; working on positioning during and after mealtime and during sleep, thickening the child’s formula and having small more frequent feedings. “Upright and prone positions have been noted to reduce episodes of reflux, in contrast with supine or reclined resting positions” (Klein & Morris p. 566). The effectiveness of positioning is controversial. The North American Society for Pediatric Gastroenterology and Nutrition (2001) state that “The amount of reflux is similar in the supine 30 degree angle and in the supine flat positions” (The North American Society for Pediatric Gastroenterology and Nutrition). Placing the child at a 30 degree angle assists in keeping the bolus away from the LES. Placing the child in the upright prone position for 30 minutes after feeding, aids in gastric emptying and lessens the likelihood of aspiration. This suggestion clashes with recent acknowledgment that prone positioning is linked to sudden infant death syndrome (SIDS); the use of the supine position is shown to reduce SIDS occurrences. Combining the two positions is recommended, to place the child in a prone position whenever he or she is awake. The only time that prone positioning during sleep is considered is if the risk of death from GER incidence outweighs the risk of SIDS.
Thickening the child’s formula gives additional nutrition for the child who is at risk for malnutrition due to reflux. Thickening with rice appears to be the preferred and safest method. Slowing down the swallow can be attained by exchanging liquids with solid foods to get the food into the system with more ease. Assortments of medications are also offered for different reasons. Before considering medications make sure your infant has been thoroughly assessed and you have factual information for applying that medication (Klein & Morris p. 567)
TRANSITION FROM BREAST/BOTTLE
The primary pattern of movement during oral intake for the infant is sucking. Sucking occurs in two pressure phases, positive and negative. The normal rate for nutritive sucking is one cycle per second. The positive pressure phase occurs when the tongue tip and the midblade of the tongue elevate to the hard palate, the jaw elevates, and the lips seal. The negative phase of the suck occurs when the tongue moves away from the hard palate, the jaw drops, the posterior cheeks contract, the soft palate elevates, and the lips remain sealed. More muscular effort is required for the negative phase of the suck. If oral motor problems exist, the coordination and efficiency of oral intake is adversely impacted, sometimes to the point that oral intake is not sufficient, and non-oral intake must be implemented. Often, even though the child has mild impairment, health crisis does not occur, weight gain is steady, but slow, and real problems do not emerge until time to transition to new food types and utensils.
Skills needed to transition from the breast/bottle to the straw in a closed container (assisted straw drinking, care-giving controls flow of liquid):
- tongue elevation to the hard palate
- liquid bolus control
- coordination of suck, swallow, breathe
Skills needed to transition from the breast/bottle to a regular straw in an open container:
- lip strength to maintain lip seal around the straw
- lip rounding
- negative pressure to pull the bolus into the mouth
- tongue elevation to the hard palate
- liquid bolus control
- coordination of suck, swallow, breathe
- head/neck control for extension/flexion
- internal jaw stability
- lip strength to maintain lip seal on the rim
- lip rounding
- negative pressure to pull the bolus into the mouth
- tongue elevation to the hard palate
- liquid bolus control
- coordination of suck, swallow, breathe
If all else fails, and if aspiration is likely, surgery must be considered. Fundoplication is done by taking a portion of the stomach and wrapping it around the lower esophageal sphincter, eliminating the upward reflux. Fundoplication should also be accompanied by a gastric emptying procedure such as pyloroplasty, puloromyotomy, or antroplasty, which can assist in decreasing retching symptoms. This procedure may worsen symptoms initially in infants and toddlers with inadequate feeding and gas bloat. Laproscopic fundoplication’s success rate accompanied with no symptoms range from 57% to 92%. Occurrence of deaths related to the surgery range from 0% to 4.7%. Some complications related to the surgery are small bowel obstruction, gas bloat syndrome, infection, pneumonia, persistent esophageal stricture and esophageal obstruction. Occasionally, achalasia and dumping syndrome can result from fundoplication. “Delayed gastric emptying and dumping syndrome can increase the risk of developing retching after a Nissen fundoplication” (Morris & Klein, 2000). GER’s natural history is that it gets better over time, so only those who don’t respond to treatment and/or with severe reflux should only consider surgery.
Some approaches to managing retching is to deal with the pain rather than fight it, and teach behavioral strategies such as relaxation, self-empowerment, focusing, breathing skills, and imagery. The authors state that “Caudill, Schnable, Zuttermeister, Benson, and Friedman (1991) found a 36% reduction in clinical visits with patients who participated in this behavioral medicine strategy”
Continued research and education of specialists is crucial to ensure the practitioner’s competency. Everyone’s goal should be to educate health care professionals, education professionals, and the public about dysphagia in children to assist in early detection. (Newman pgs. 9 – 10)
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