 Transition to Oral Feeding Is Not Always Easy . . . page 1 D. Secker, MSc, RD Clinical Dietitian The Hospital for Sick Children, Toronto Survival of infants born prematurely or with congenital anomalies and complex medical conditions has increased, as has recognition of the importance of maintaining optimal nutrition during critical periods of growth and development. As a result, tube feeding and parenteral nutrition are commonly used to temporarily meet fluid and nutrient requirements until the infant or toddler can be nourished by mouth. As these infants and toddlers begin to recover and the problems that originally prevented oral feeding are resolved, the transition to oral feeding must begin. For premature infants, the transition to oral feeding should be approached cautiously, as they may experience physiologic instability (e.g. hypoxia, bradycardia) due to difficulties in integrating breathing into the suck-swallow cycle. Newborn, full-term infants requiring tube feeding for short periods of time (weeks) who return to oral feedings in the first six months of life often make the transition to oral feeding with little difficulty. Older infants and toddlers may display oral-motor, sensory, and developmental feeding problems and behaviors that make weaning difficult. Oral hypersensitivity, a hyperactive gag reflex and less mature coordination of the bite-chew-swallow sequence are commonly observed. Because of oral hypersensitivity and dyscoordination the child may prefer food consistency that needs only primary oral movements and can be swallowed easily with the help of gravity. Textures requiring more tongue-lip-cheek coordination frequently provoke a gag reflex. Negative responses to food such as refusing to open the mouth, gagging and vomiting at the sight or taste of foods, or refusing oral intake altogether may also occur. (1) Because problems with feeding may result in significant negative nutritional, developmental and psychological sequelae, early recognition is important. (2) What causes feeding problems? Infants who are at the highest risk for oral feeding difficulties include premature infants who have required prolonged ventilatory assistance, have chronic lung disease or a history of CNS insult. Full-term infants or toddlers with a history of complex health problems, developmental delay, traumatic feeding experiences or psychosocial problems within their family are more likely to experience difficulties in moving towards oral feeds. Development of feeding problems is often influenced by a variety of factors. The most frequent obstacle to establishing oral feeding in tube-dependent infants is the inability or failure to offer oral feeding experiences during the "critical period" for development of oral feeding. During this sensitive period of oral-motor development, which occurs between 6-10 months, the infant must learn to control, coordinate and trust the mechanics of feeding. (3) When the time for developing these skills is missed, most children learn to mistrust their oral abilities, leading to many of the oral feeding problems experienced by tube-fed children. The fear of oral and gastrointestinal discomfort from the introduction, swallowing, and digestion of food, or the fear of choking may lead to hesitancy to eat. Frequent gagging reinforces the fear of oral feeding, and sustains the problem. Gagging may be the infant's way of saying 'I don't know how/what to do with this stuff in my mouth, so I'll gag and you'll stop'. Post-traumatic feeding disorder typically occurs in children with a history of previous distressing medical procedures such as intubation, oral or nasal suctioning, or the placement of nasogastric or orogastric tubes. (4) Oral hypersensitivity and aversion to fluids and/or foods results from memories of these unpleasant procedures which leads the child to perceive that anything approaching their mouth is potentially painful. Developmentally, tube feedings may interfere with the pleasurable experience of eating. Children who have been chronically tube fed often fail to link sensations associated with eating with sensations in their stomach and lack the concept of eating as a regulator for satiety. The smells, textures and sight of food are unfamiliar sensory cues to many tube-fed children. Tube feeding is often administered in bed - a location not typically associated with eating or socialization with others. Tube-fed children who are absent from family mealtimes may fail to develop appropriate mealtime behaviors. Instead they demonstrate feeding misbehaviors such as crying, refusing to open the mouth, pushing food away, or total refusal to eat. (5) Without proper management, these inappropriate behaviors result in a considerable increase in attention provided to the child as well as the opportunity for them to exert control over others. Feeding difficulties are a source of great stress to parents. Many parents blame themselves or feel blamed by others when problems arise. (6) Desperate to help their child gain weight, parents may resort to forced feeding, which typically backfires and worsens the feeding problems. Preventing feeding problems While the majority of the literature discusses the management of eating problems (1,5,7,8,9), a few authors have addressed the prevention of feeding problems. (2, 10) Although there is little scientific evidence regarding efficacy of the various methods, it is common practice to provide the infant with opportunities to practice oral-feeding skills through the developmentally appropriate use of a pacifier or teething ring, as soon as tube feedings are initiated. Tube feeding should be given while the infant or child is seated at a table at mealtime. Where possible, they should be given the opportunity to see, smell, taste and play with food while being tube fed. These experiences foster a positive association between being fed, food and the social enjoyment of being part of a family activity. When is it appropriate to consider oral feeding? An infant is safe and ready to feed orally if he has the ability to gag and reflexively protect his airway, and demonstrates rhythmic, non-nutritive sucking with even respirations and swallowing of secretions. For premature infants, there is a wide variation in the gestational age that corresponds with these abilities. Generally, 32 weeks gestational age is the earliest an infant would demonstrate some limited ability to coordinate suck, swallow and breathing sequences. Lemons and Lemons (7) have described techniques for facilitating breathing and reduction of hypoventilation during breathing. The original medical problems that warranted tube feeding (e.g. anatomic or functional impediments to swallowing) must be resolved or stabilized. Swallowing ability should appear appropriate; common signs of abnormal swallowing include choking, coughing, regurgitation, audible 'gulping' sounds, and difficulty swallowing secretions. Videofluoroscopic swallowing studies to document adequate swallowing mechanisms or radiographic testing for the presence of reflux are not routinely done unless clinically indicated. Nutritional status should be good, with weight for height indicating the presence of some nutrition reserves so that a short period of inadequate weight gain at the start of weaning can be tolerated. |
