Oral feeding in low birth weight infants

Sensorized pacifier to quantify the rhythmicity of non-nutritive sucking: A preliminary study on newborns

Non-nutritive sucking (NNS) is one of the most significant spontaneous actions of infants. The suction/expression rhythmicity of NNS remains unknown. We developed a sensorized pacifier for an objective measurement of NNS. Two miniaturized digital pressure sensors are embedded into a commercial pacifier and they acquired suction and expression pressures simultaneously. Experimental tests with nine newborns confirmed that our device is suitable for the measurement of the natural NNS behavior and for the extrapolation of parameters related to the suction/expression rhythmicity. Preliminary results encourage future studies to evaluate the possibility to use these parameters as indicators of oral feeding readiness of premature infants.

Impact of Oral Sensory Motor Stimulation on Feeding Performance, Length of Hospital Stay, and Weight Gain of Preterm Infants in NICU

Background:

One of the limiting factors for early hospital discharge in preterm infants is their inability to feed sufficiently to obtain consistent weight gain. Therefore, feeding difficulty is one of the most significant issues with which a preterm infant is faced.

Objectives:

The purpose of this study was to examine the effect of oral sensory motor stimulation on feeding performance, length of hospital stay, and weight gain in preterm infants at 30 - 32 weeks of gestational age.

Patients and Methods:

Premature infants (n = 20) were randomly assigned to experimental and control groups. The experimental group received oral sensory motor stimulation of the oral structures (15 minutes / day) for 10 successive days, while these stimulations were not offered to the control group. Days elapsed to achieve oral feeding, length of hospital stay, and weight gain in the two groups were assessed.

Results:

Transition to oral feeding was acquired significantly earlier in the infants in the experimental group than in the controls: 13 and 26 days, respectively (P < 0.001). Likewise, the length of hospitalization was significantly shorter in the experimental group than in the control group: 32 days and 38 days, correspondingly (P < 0.05). The two groups showed no significant difference in terms of weight gain in the first, second, third, and fourth weeks of birth: first week: 100 vs. 110; second week: 99 vs. 111; third week: 120 vs. 135; and fourth week: 129 vs. 140.

Conclusions:

The present research revealed that the number of days to reach oral feeding in our preterm babies was decreased by oral motor stimulation, which in turn conferred earlier hospital discharge.

Development of Suck and Swallow Mechanisms in Infants

Preterm infants' hospital discharge is often delayed due to their inability to feed by mouth safely and competently. No evidence-based supported guidelines are currently available for health-care professionals caring for these infants. Available interventions advocating benefits are not readily acknowledged for lack of rigorous documentation inasmuch as any improvements may ensue from infants' normal maturation. Through research, a growing understanding of the development of nutritive sucking skills has emerged, shedding light on how and why infants may encounter oral feeding difficulties due to the immaturity of specific physiologic functions. Unfortunately, this knowledge has yet to be translated to the clinical practice to improve the diagnoses of oral feeding problems through the development of relevant assessment tools and to enhance infants' oral feeding skills through the development of efficacious preventive and therapeutic interventions. This review focuses on the maturation of the various physiologic functions implicated in the transport of a bolus from the oral cavity to the stomach. Although infants' readiness for oral feeding is deemed attained when suck, swallow, and respiration are coordinated, we do not have a clear definition of what coordination implies. We have learned that each of these functions encompasses a number of elements that mature at different times and rates. Consequently, it would appear that the proper functioning of sucking, the swallow processing, and respiration need to occur at two levels: first, the elements within each function must reach an appropriate functional maturation that can work in synchrony with each other to generate an appropriate suck, swallow process, and respiration; and second, the elements of all these distinct functions, in turn, must be able to do the same at an integrative level to ensure the safe and efficient transport of a bolus from the mouth to the stomach.

A self-paced oral feeding system that enhances preterm infants' oral feeding skills

AIM

Very low birth weight (VLBW) infants have difficulty transitioning to independent oral feeding, be they breast- or bottle-feeding. We developed a 'self-paced' feeding system that eliminates the natural presence of the positive hydrostatic pressure and internal vacuum build-up within a bottle during feeding. Such system enhanced these infants' oral feeding performance as monitored by overall transfer (OT; % ml taken/ml prescribed), rate of transfer (RT; ml/min over an entire feeding). This study hypothesizes that the improvements observed in these infants resulted from their ability to use more mature oral feeding skills (OFS).

METHODS

'Feeders and growers' born between 26-29 weeks gestation were assigned to a control or experimental group fed with a standard or self-paced bottle, respectively. They were monitored when taking 1-2 and 6-8 oral feedings/day. OFS was monitored using our recently published non-invasive assessment scale that identifies 4 maturity levels based on infants' RT and proficiency (PRO; % ml taken during the first 5 min of a feeding/total ml prescribed) during bottle feeding.

RESULTS

Infants oral feeding outcomes, i.e., OT, RT, PRO, and OFS maturity levels were enhanced in infants fed with the self-paced vs. standard bottle (p ≤ 0.007).

CONCLUSION

The improved oral feeding performance of VLBW infants correlated with enhanced OFS. This study is a first to recognize that VLBW infants' true OFS are more mature than recognized. We speculate that the physical properties inherent to standard bottles that are eliminated with the self-paced system interfere with the display of their true oral feeding potential thereby hindering their overall oral feeding performance.

Supporting Oral Feeding Skills Through Bottle Selection

Infants who have feeding difficulties often struggle with coordinating sucking, swallowing, and breathing, and have difficulty eating sufficient quantities for adequate growth. Speech-language pathologists (SLPs) need advanced expertise across a number of areas (e.g., development, medical, swallowing) to work effectively with these young infants, and they use a variety of strategies when treating this population. Therapists working with infants who have feeding difficulties use bottles as a primary therapy tool; how the infant tolerates the flow rate from the bottle/nipple is a major consideration. Caregivers must understand the influence of bottle/nipple flow rates on eating skills, so they can support the emerging oral skill development for these fragile infants, and help parents decide what bottle system to use in their home. Both infant and equipment factors influence bottle/nipple flow rates. This article discusses the influencing factors that need to be considered when determining the optimal flow rate for an individual infant.

Preterm newborn readiness for oral feeding: systematic review and meta-analysis

PURPOSE: To identify and systematize the main studies on the transition from enteral to oral feeding in preterm infants. RESEARCH STRATEGY: Articles that describe the transition from oral to enteral feeding in preterm infants were located in MEDLINE, LILACS, and SciELO databases. SELECTION CRITERIA: Original studies, with available abstract, published in the last 10 years were included. DATA ANALYSIS: Analysis of the methodology and the main results of the studies, and meta-analysis of the effects of sensory-motor-oral stimulation at the time of transition to full oral feeding and duration of hospitalization were conducted. RESULTS: Twenty-nine national and international publications were considered. Most studies were clinical trials (44.8%) and did not use rating scales to start the transition process (82.7%). In the meta-analysis, positive effect of stimulation of the sensory-motor-oral system was observed with respect to the transition time to oral diet (p=0.0000), but not in relation to the length of hospital stay (p=0.09). However, heterogeneity between studies was found both in the analysis of the transition time to full oral feeding (I2=93.98) and in the length of hospital stay (I2=82.30). CONCLUSION: The transition to oral feeding is an important moment, and various physical and clinical characteristics of preterm infants have been used to describe this process. Despite the impossibility of generalizing the results due to the heterogeneity of the studies, we have noted the importance of strategies for stimulation of sensory-motor-oral system to decrease the period of transition to full oral feeding system.

Effect of nonnutritive sucking and oral stimulation on feeding performance in preterm infants: a randomized controlled trial

OBJECTIVES

To evaluate the effectiveness of nonnutritive sucking (NNS) and oral stimulation (OS), either applied alone or in combination, to reduce the transition time from tube feeding to independent oral feeding.

DESIGN

Randomized controlled trial.

SETTING

A 40-bed neonatal ICU in a university hospital in the People's Republic of China.

PATIENTS

A total of 120 preterm infants were admitted to the neonatal ICU from December 2012 to July 2013.

INTERVENTIONS

Oral motor interventions.

MEASUREMENTS AND MAIN RESULTS

One hundred twelve preterm infants were assigned to three intervention groups (NNS, OS, and combined NNS + OS) and one control group. Primary outcome was the number of days needed from introduction of oral feeding to autonomous oral feeding (transition time). Secondary outcome measures were the rate of milk transfer (mL/min), proficiency (intake first 5 min/volume ordered), volume transfer (volume transferred during entire feeding/volume prescribed), weight, and hospital length of stay. Transition time was reduced in the three intervention groups compared with the control group (p < 0.001). The milk transfer rate in the three intervention groups was greater than in the control group (F3,363 = 15.37; p < 0.001). Proficiency in the NNS and OS groups did not exceed that in the control group while the proficiency in the NNS + OS group was greater than that in the control group at the stage when the infants initiated the oral feeding (p = 0.035). Among all groups, no significant difference was found on weight gain and length of stay.

CONCLUSIONS

The combined NNS + OS intervention reduced the transition time from introduction to independent oral feeding and enhanced the milk transfer rate. The combined intervention seems to have a beneficial effect on oral feeding proficiency in preterm infants.

Noninvasive evaluation of swallowing sound is an effective way of diagnosing feeding maturation in newborn infants

AIM

Despite extensive research, there is still controversy regarding the time at which sucking and swallowing functions mature in preterm infants. This study aimed to evaluate maturation using the noninvasive method of swallowing sound.

METHODS

We compared 52 preterm infants of between 27 and 36 weeks' gestational age with a control group of 42 healthy full-term infants. Feeding performance was based on swallowing data collected during two-minute audio recordings. The following variables were generated for each evaluation: total number of swallows, total number of rhythmic swallows, total number of resting intervals, average time between resting intervals, average time between swallows, average time between rhythmic swallows, maximum number of rhythmic swallows and volume of milk ingested. The dependency of the variables on postmenstrual age was also investigated.

RESULTS

The volume of milk ingested by the preterm infants and the maximum number of rhythmic swallows were positively correlated with postmenstrual age (PMA). The preterm infants reached the 10th percentile of the control infants at 34-35 weeks' PMA and were not significantly different from the control infants at 38-40 weeks' PMA.

CONCLUSION

Swallowing sound can be used to assess feeding maturation in preterm infants during neonatal intensive care unit follow-up.

Technological solutions and main indices for the assessment of newborns' nutritive sucking: a review

Nutritive Sucking (NS) is a highly organized process that is essential for infants' feeding during the first six months of their life. It requires the complex coordination of sucking, swallowing and breathing. The infant's inability to perform a safe and successful oral feeding can be an early detector of immaturity of the Central Nervous System (CNS). Even though the importance of early sucking measures has been confirmed over the years, the need for standardized instrumental assessment tools still exists. Clinicians would benefit from specifically designed devices to assess oral feeding ability in their routine clinical monitoring and decision-making process. This work is a review of the main instrumental solutions developed to assess an infant's NS behavior, with a detailed survey of the main quantities and indices measured and/or estimated to characterize sucking behavior skills and their development. The adopted sensing measuring systems will be described, and their main advantages and weaknesses will be discussed, taking into account their application to clinical practice, or to at-home monitoring as post-discharge assessment tools. Finally, the study will highlight the most suitable sensing solutions and give some prompts for further research.

Efficacy of semielevated side-lying positioning during bottle-feeding of very preterm infants: a pilot study

Very preterm (VP, ≤30 wk gestational age) infants are at risk for impaired lung function, which significantly limits their ability to eat. A semielevated side-lying (ESL) position is a feeding strategy that may improve oral feeding by supporting breathing during feeding. The study evaluated the efficacy of the ESL position compared with the semielevated supine (ESU) position on physiological stability and feeding performance of bottle-fed VP infants. Using a within-subject crossover design, 6 VP infants were bottle-fed twice on 1 day, in both the ESL and ESU positions in a random order. Physiological stability (heart rate, oxygen saturation [SaO2], and respiratory characteristics) and feeding performance (percent intake, proficiency, efficiency, and duration of feeding) were measured before and/or during feeding. Very preterm infants fed in the ESL position demonstrated significantly less variation in heart rate, less severe and fewer decreases in heart rate, respiratory rate that was closer to the prefeeding state, shorter and more regular intervals between breaths, and briefer feeding-related apneic events. No significant differences for SaO2 or feeding performance were found. The findings indicate that the ESL position may support better regulation of breathing during feeding, thereby allowing VP infants to better maintain physiological stability throughout feeding.

Cue-based feeding in the NICU: using the infant's communication as a guide

Although studies have shown cue-based feeding can lead to earlier achievement of full oral feeding, the successful implementation of cue-based feeding has been constrained by the volume-driven culture, which has existed for many years in the NIC U. This culture was built on the notion that a "better" nurse is one who could "get more in," and infants who are "poor feeders" are ones who "can't take enough." The infant who feeds faster is often viewed as more skilled in this task-oriented approach. The feeding relationship and the infant's communication about the experience of feeding may not be nurtured. This article will explain the central role of the preterm infant's communication in successful cue-based feeding. When the infant is perceived as having meaningful behavior (i.e., communicative intent), the focus changes from a volume-driven to a co-regulated approach, through which the infant guides the caregiver. This is cue-based feeding.

Feeding behaviour and performance of preterm neonates on Paladai feeding

AIM

To evaluate the feeding behaviour and performance of preterm neonates receiving feeds by paladai (a small beaked receptacle).

METHODS

We enrolled stable neonates - 10 each in 28-30 weeks [group I] and 31-32 weeks gestation [group II], and offered them paladai feeds. We recorded the feeding sessions on alternate days until they were on full enteral feeds. The outcome variables were (1) feeding behaviour, as assessed by changes in states of wakefulness, oromotor functions and coordination between breathing and swallowing; (2) feeding performance, as assessed by proficiency and efficiency.

RESULTS

A total of 47 and 27 sessions were studied in groups I and II, respectively. The median postconceptional age (PCA) at start of paladai feeding was 30 (range, 29-32) and 32 (31-32) weeks in the two groups. The infants accepted paladai feedings in all behavioural states. Incoordination between feeding and breathing was observed in about 25% of the sessions in both the groups. We observed a rapid improvement in feeding performance with experience - the median proficiency improved from 5.5 to 10.1 mL/min and 6.2-11.5 mL/min in groups I and II, respectively. The proficiency of group I infants at a median PCA of 30.9 weeks was higher than that of group II infants at median PCA 31.7 weeks.

CONCLUSION

Stable preterm neonates can be fed with paladai from 30 weeks PCA. The oropharyngeal ability is possibly influenced more by the postnatal experience than by maturity at birth.

Reading the Feeding

The amount of milk a preemie drinks largely determines readiness for discharge from the neonatal intensive care unit. But just because an infant feeds well today doesn't mean it will last. In the long term, fostering a child's consistent, positive response to feeding may be more important.

Oral-motor function and feeding intervention

This article presents the elements of the Oral Motor Intervention section of the Infant Care Path for Physical Therapy in the Neonatal Intensive Care Unit (NICU). The types of physical therapy interventions presented in this path are evidence based as well as infant driven and family focused. In the context of anticipated maturation of suck-swallow-breathe coordination, the timing and methods for initiation of oral feedings and transition from gavage to full breast or bottle-feedings are presented with supporting evidence.

The use of nonnutritive sucking to facilitate oral feeding in a term infant: a single case study

This individual case study presents an evaluation of and reflection on the use of nonnutritive sucking as a technique to facilitate nutritive sucking with an infant with feeding difficulties. Nonnutritive sucking is used in a variable way with mainly premature or sick infants. However, the rationale underpinning use of such an approach is not clear. The infant participant in this study, Baby H, was born at 37 weeks. This case illustrates the use of nonnutritive sucking as an approach with supported rationales for promoting transition toward oral feeding with infants who have complex needs and who are term infants. The literature focuses on using nonnutritive sucking with premature infants who have no additional difficulties such as hypoxic neonatal encephalopathy, meconium aspiration, sepsis, or severe perinatal asphyxia. The intervention carried out with Baby H demonstrates that nonnutritive sucking can contribute toward the management of an infant's feeding development. Baby H took 23 days to develop a sequential nonnutritive sucking pattern, but her ability to transfer this to nutritive sucking and safe feeding took the first 17 months of this infant's life. This study is unique in that it explored the issues involved with a term infant who had complex needs that impacted on feeding development. It is important because many practitioners use nonnutritive sucking with infants who have complex needs.

Oral feeding readiness in the neonatal intensive care unit

Oral feeding is a complex sensorimotor process that is influenced by many variables, making the introduction and management of oral feeding a challenge for many health care providers. Feeding practice guided by tradition or a trial-and-error approach may be inconsistent and has the potential to delay the progression of oral feeding skills. Oral feeding initiation and management should be based on careful, individualized assessment of the NICU infant and requires an understanding of neonatal physiology and neurodevelopment. The purpose of this article is to help the health care provider with this complex process by (a) defining oral feeding readiness, (b) describing the importance of oral feeding in the NICU and the physiology of feeding, and (c) providing a review of the literature regarding the transition from gavage to oral feeding in the NICU.

Influences on breastfeeding outcomes for healthy term and preterm/sick infants

OBJECTIVE

This study investigated breastfeeding outcomes and factors associated with duration of breastfeeding in cohorts of healthy term and sick/preterm infants.

STUDY DESIGN

Follow-up was conducted of 87 sick/preterm and 92 term healthy infants during the 9 months following discharge from two Western Australian hospitals.

RESULTS

When corrected for gestational age, breastfeeding duration did not differ between the entire cohort of sick/preterm and term healthy groups. Multivariable analysis showed that early cessation of breastfeeding was more likely for infants born at <33 weeks of gestation (hazard ratio [HR ]=2.05, 95% confidence interval [CI]=1.14-3.69), mothers who had previously breastfed for <6 months (HR=3.67, 95% CI=2.12-6.37), and for mothers who perceived breastfeeding to be important rather than very important (HR=2.58, 95% CI=1.59-4.20).

CONCLUSIONS

Maternal perceptions of breastfeeding as "important" rather than "very important" and previous breastfeeding duration of <6 months are negatively associated with breastfeeding duration; these factors can be identified and addressed during pregnancy and in the postnatal period. Preterm infants born at <33 weeks of gestation have a shorter breastfeeding duration than those born at a later gestation.

Oral and non-oral sensorimotor interventions enhance oral feeding performance in preterm infants

AIM

The aim of this study was to determine whether oral, tactile/kinaesthetic (T/K), or combined (oral+T/K) interventions enhance oral feeding performance and whether combined interventions have an additive/synergistic effect.

METHOD

Seventy-five preterm infants (mean gestational age 29 wk; standard error of the mean [SEM] 0.3 wk; mean birthweight 1340.3g; SEM 52.5 g; 49 males and 26 females) were randomly assigned to one of three intervention groups or a control group. The oral group received sensorimotor input to the oral structures, the T/K group received sensorimotor input to the trunk and limbs, and the combined group received both. The outcomes were time from introduction of nipple feeding to independent oral feeding (d), proficiency (intake in the first 5 min, %), volume transfer (%), rate of transfer (mL/min), volume loss (%), and length of hospital stay (d).

RESULTS

Infants in the three intervention groups achieved independent oral feeding 9-10 days earlier than those in the control group (p<0.001; effect size 1.9-2.1). Proficiency (p ≤ 0.002; effect size 0.7-1.4) at the time of one to two and three to five oral feedings per day, volume transfer (p ≤ 0.001; effect size 0.8-1.1) at one to two, three to five, and six to eight oral feedings per day, and overall rate of transfer (p ≤ 0.018; effect size 0.8-1.1) were greater, and overall volume losses were less (p ≤ 0.007; effect size 0.9-1.1), than in the control group (p ≤ 0.042). The combined group attained independent oral feeding at a significantly younger postmenstrual age than controls (p=0.020) and had clinically greater proficiency than the T/K group (p=0.020; effect size 0.7) and oral group (p=0.109; effect size 0.5). Length of hospital stay was not significantly different between groups (p=0.792; effect size 0.02-0.3).

INTERPRETATION

Oral and T/K interventions accelerated the transition from introduction to independent oral feeding and enhanced oral feeding skills. T/K has beneficial effects beyond the specific targeted system. The combined sensorimotor intervention led to an additive/synergistic effect for proficiency, further benefiting this population.

Feeding Difficulties in Preterm Infants

Preterm infants often display difficulty establishing oral feeding in the weeks following birth. This article aims to provide an overview of the literature investigating the development of feeding skills in preterm infants, as well as of interventions aimed at assisting preterm infants to develop their feeding skills. Available research suggests that preterm infants born at a lower gestational age and/or with a greater degree of morbidity are most at risk of early feeding difficulties. Respiratory disease was identified as a particular risk factor. Mechanisms for feeding difficulty identified in the literature include immature or dysfunctional sucking skills and poor suck–swallow–breath coordination. Available evidence provides some support for therapy interventions aimed at improving feeding skills, as well as the use of restricted milk flow to assist with maintaining appropriate ventilation during feeds. Further research is needed to confirm these findings, as well as to answer remaining clinical questions.

Development of a technique for evaluating temporal parameters of sucking in breastfeeding preterm newborns

AIMS

The aim of the current study was to developed and test the reliability of a technique for measuring temporal parameters of sucking in breastfeeding infants.

METHODS

The technique was developed using a cohort of 11 term and 12 preterm infants, and subsequently evaluated using a cohort of 43 preterm infants. Measurements related to sucking pressure in the term and preterm infants were acquired. The signals were recorded for 5 min, saved on a computer, and stored for analysis. For purposes of analysis, the minute with the highest quality signal was chosen. Signal analysis was performed by two researchers, and inter- and intra-observer agreement was assessed. The newborns in the sample had different gestational ages.

RESULTS

A technique was developed for the analysis of temporal parameters of sucking during breastfeeding and evaluated in 43 preterm infants with different gestational ages for the following variables: number of bursts per minute, number of sucks per burst, sucking rate, pause rate, and duration of pauses. The intra-observer agreement was 0.85 and the inter-observer agreement was 0.85.

CONCLUSIONS

The technique that was developed and validated proved capable of measuring temporal parameters of sucking in breastfeeding newborns.

Feeding with cross-cut teats has better sucking effects and oxygenation in preterm infants with chronic lung disease

AIM

To compare effects of single-hole and cross-cut teats on feeding performance, oral movement and cardiorespiratory parameters in preterm infants with chronic lung disease.

BACKGROUND

Infants' feeding performance and physiological stability are affected by the shape and hole size of teats because of varied milk flow. The single-hole teat could facilitate efficient milk intake in healthy preterm infants. In preterm infants with chronic lung disease, few studies have determined which type of teat is suitable for feeding.

DESIGN

A crossover study design was conducted.

METHODS

Twenty preterm infants with chronic lung disease were studied in a neonatal intensive care unit. During the early stage in transitional period of oral feeding, each infant was provided with a small single-hole, an intermediate single-hole and a cross-cut teat with diameters of 0.45-0.5 mm, 0.7-0.8 mm and 2.0 mm, respectively, for three consecutive feeds in a random order. Feeding performance, oral movement, heart rate, respiratory rate and oxygen saturation (SpO(2)) were measured.

RESULTS

Infants fed with single-hole teats had a shorter duration of feeding time (p < 0.001) and higher feeding efficiency (p < 0.001) compared with the cross-cut teats. However, infants fed with cross-cut teats had a higher sucking pressure (p < 0.001), more sucks (p < 0.001) and bursts (p < 0.001), longer sucking duration (p = 0.002) and higher respiratory rate (p = 0.005) and SpO(2) (p = 0.014) than infants fed with single-hole teats.

CONCLUSIONS

For preterm infants with chronic lung disease, cross-cut teats facilitate feeding coordination and physiological stability during the early stage of the transition from tube to oral feeding.

RELEVANCE TO CLINICAL PRACTICE

Cross-cut teat can be considered for preterm infants with chronic lung disease to increase safety and self-regulation in the early stage of the transition from tube to oral feeding.

A novel approach to assess oral feeding skills of preterm infants

BACKGROUND

There is no well-defined means to identify the level of oral feeding skills (OFS) in preterm infants.

OBJECTIVE

To determine whether OFS as reflected by the combination of proficiency (PRO, %ml taken during the first 5 min/ml prescribed) and rate of milk transfer (RT, ml/min) correlates with gestational age (GA), oral feeding performance (OT, %ml taken during a feeding/ml prescribed) and days from start to independent oral feeding (SOF-IOF). Our working premises are that PRO is reflective of infants' actual feeding skills when fatigue is minimal and RT, monitored over an entire feeding session, reflects their overall skills when fatigue comes into play.

METHODS

Infants (26-36 weeks GA) with prematurity as their principal diagnosis were recruited and monitored at their first oral feeding. GA was divided into 3 strata, 26-29, 30-33, and 34-36 weeks GA. OFS was divided into 4 levels delineated by PRO (≥ or <30%) and RT (≥ or <1.5 ml/min). ANOVA with post-hoc Bonferroni and multiple regression analyses were used.

RESULTS

OFS levels were correlated with GA. OT, PRO, and days from SOF-IOF were associated with OFS and GA, whereas RT was only correlated with OFS levels.

CONCLUSIONS

OFS is a novel objective indicator of infants' feeding ability that takes into account infants' skills and endurance. As a clinical tool, it can help caretakers monitor infants' skills as they transition to oral feeding and identify oral feeding issues arising from immature skills and/or poor endurance.

Effectiveness of Cheek and Jaw Support to Improve Feeding Performance of Preterm Infants

OBJECTIVE. We examined the effects of cheek and jaw support on the feeding ability of inefficient feeders born prematurely.

METHOD. Twenty preterm infants served as their own controls. Each infant received either intervention (feeding with oral support) or control (feeding without oral support) for 2 consecutive feedings per day on 2 consecutive days.

RESULTS. Infants displayed a greater intake rate during the intervention feedings, both during the first 5 min (p = .046) and throughout the entire feeding (p = .023). The percentage of leakage during the first 5-min feeding was smaller in the intervention condition than in the control condition (p = .040). No significant differences were found between the two conditions in the sucking, physiological, and alertness variables.

CONCLUSION. Findings confirm oral support as a safe and effective strategy to improve the feeding performance of preterm infants who are poor feeders.

Relationship of Neonatal Oral Motor Assessment Scale to Feeding Performance of Premature Infants

OBJECTIVE: Some premature infants require prolonged tube-feeding, beyond term equivalent gestational age. Tools that could prospectively identify such infants from among otherwise healthy patients are needed. We examined how well the Neonatal Oral Motor Assessment Scale (NOMAS) predicts premature infants' transition from tube to oral feeding. DESIGN: Data from a prospective study of sucking behavior as a predictor of feeding skills were used to examine the relationship of NOMAS and other nominal predictors to pre-defined feeding milestones. SETTING: Neonatal intensive Care Unit PATIENTS: 51 tube-fed, premature infants METHODS: NOMAS was administered soon (<72 hours) after oral feeding was initiated, and weekly thereafter, until infants reached full oral feeding. A timed measure of feeding efficiency was also done as oral feeding was initiated. A standardized, permissive protocol for feeding advance was used. Nonparametric rank sum tests and ANOVA were used to relate NOMAS, feeding efficiency, and other baseline variables to feeding milestones. RESULTS: Gestational age at birth, birth weight, and initial feeding efficiency predicted shorter transition and earlier acquisition to full oral feeding; NOMAS scores did not predict feeding outcomes. CONCLUSIONS: NOMAS was a poor predictor, while feeding efficiency and other baseline traits were better predictors of feeding skills in premature infants.

Improving Feeding Outcomes in the NICU: Moving From Volume-Driven to Infant-Driven Feeding

Current research on feeding outcomes after discharge from the neonatal intensive care unit (NICU) suggests a need to critically look at the early underpinnings of persistent feeding problems in extremely preterm infants. Concepts of dynamic systems theory and sensitive care-giving are used to describe the specialized needs of this fragile population related to the emergence of safe and successful feeding and swallowing. Focusing on the infant as a co-regulatory partner and embracing a framework of an infant-driven, versus volume-driven, feeding approach are highlighted as best supporting the preterm infant's developmental strivings and long-term well-being.

Quantification of intraoral pressures during nutritive sucking: methods with normal infants

We report quantitative measurements of ten parameters of nutritive sucking behavior in 91 normal full-term infants obtained using a novel device (an Orometer) and a data collection/analytical system (Suck Editor). The sucking parameters assessed include the number of sucks, mean pressure amplitude of sucks, mean frequency of sucks per second, mean suck interval in seconds, sucking amplitude variability, suck interval variability, number of suck bursts, mean number of sucks per suck burst, mean suck burst duration, and mean interburst gap duration. For analyses, test sessions were divided into 4 × 2-min segments. In single-study tests, 36 of 60 possible comparisons of ten parameters over six pairs of 2-min time intervals showed a p value of 0.05 or less. In 15 paired tests in the same infants at different ages, 33 of 50 possible comparisons of ten parameters over five time intervals showed p values of 0.05 or less. Quantification of nutritive sucking is feasible, showing statistically valid results for ten parameters that change during a feed and with age. These findings suggest that further research, based on our approach, may show clinical value in feeding assessment, diagnosis, and clinical management.

Maturational changes in the feeding behaviour of infants - a comparison between breast-feeding and bottle-feeding

AIM

To obtain a better understanding of the changes in feeding behaviour from 1 to 6 months of age. By comparing breast- and bottle-feeding, we intended to clarify the difference in longitudinal sucking performance.

METHODS

Sucking variables were consecutively measured for 16 breast-fed and eight bottle-fed infants at 1, 3 and 6 months of age.

RESULTS

For breast-feeding, number of sucks per burst (17.8 +/- 8.8, 23.8 +/- 8.3 and 32.4 +/- 15.3 times), sucking burst duration (11.2 +/- 6.1, 14.7 +/- 8.0 and 17.9 +/- 8.8 sec) and number of sucking bursts per feed (33.9 +/- 13.9, 28.0 +/- 18.2 and 18.6 +/- 12.8 times) at 1, 3 and 6 months of age respectively showed significant differences between 1 and 6 months of age (p < 0.05). The sucking pressure and total number of sucks per feed did not differ among different ages. Bottle-feeding resulted in longer sucking bursts and more sucks per burst compared with breast-feeding in each month (p < 0.05).

CONCLUSION

The increase in the amount of ingested milk with maturation resulted from an increase in bolus volume per minute as well as the higher number of sucks continuously for both breast- and bottle-fed infants.

The oral motor capacity and feeding performance of preterm newborns at the time of transition to oral feeding

The objective of the present study was to determine the oral motor capacity and the feeding performance of preterm newborn infants when they were permitted to start oral feeding. This was an observational and prospective study conducted on 43 preterm newborns admitted to the Neonatal Intensive Care Unit of UFSM, RS, Brazil. Exclusion criteria were the presence of head and neck malformations, genetic disease, neonatal asphyxia, intracranial hemorrhage, and kernicterus. When the infants were permitted to start oral feeding, non-nutritive sucking was evaluated by a speech therapist regarding force (strong vs weak), rhythm (rapid vs slow), presence of adaptive oral reflexes (searching, sucking and swallowing) and coordination between sucking, swallowing and respiration. Feeding performance was evaluated on the basis of competence (defined by rate of milk intake, mL/min) and overall transfer (percent ingested volume/total volume ordered). The speech therapist's evaluation showed that 33% of the newborns presented weak sucking, 23% slow rhythm, 30% absence of at least one adaptive oral reflex, and 14% with no coordination between sucking, swallowing and respiration. Mean feeding competence was greater in infants with strong sucking fast rhythm. The presence of sucking-swallowing-respiration coordination decreased the days for an overall transfer of 100%. Evaluation by a speech therapist proved to be a useful tool for the safe indication of the beginning of oral feeding for premature infants.

Deprivation and dysphagia in premature infants

The developmental trajectory of feeding features increasingly rhythmic ingestive behavior patterns. Sucking and swallowing by the fetus and infant, including fetal consumption of amniotic fluid, depend upon brainstem central pattern generators whose activity is increasingly influenced by chemosensory and oral-tactile input. This neurobiological fact underlies the clinical discovery that oral-tactile stimulation via pacifier stimulates ingestive behavior in tube-fed, premature infants and improves their feeding skills. However, little is known regarding the degree to which oral sensory deprivation may contribute to feeding problems in these patients. Evidence of deprivation-induced neuropathologic effects in rodents further underlines the potential impact of sensory deprivation in premature newborns, whose transition period from tube to oral feeding often lasts weeks beyond term equivalent gestational age. Studies exploring the link between early dysphagia and later developmental impairment could clarify experiential antecedents of cerebral injury. Trials of sensory interventions to promote feeding development are warranted.

A controlled-flow vacuum-free bottle system enhances preterm infants' nutritive sucking skills

We have shown that a controlled-flow vacuum-free bottle system (CFVFB) vs. a standard bottle (SB) facilitates overall transfer and rate of milk transfer, and shortens oral feeding duration in very-low-birth-weight (VLBW) infants. We aimed to understand the basis by which this occurs. Thirty infants (19 males; 27 +/- 1 weeks gestation) were randomized to a CFVFB or SB. Outcomes monitored at 1-2 and 6-8 oral feedings/day when infants were around 34 and 36 weeks postmenstrual age, respectively, included: overall transfer (% volume taken/volume prescribed), rate of milk transfer (ml/min), sucking stage, frequency of suction (#S/s) and expression (#E/s), suction amplitude (mmHg), and sucking burst duration (s). At both periods we confirmed that infants using a CFVFB vs. SB demonstrated greater overall transfer and rate of milk transfer, along with more mature sucking stages. Suction and expression frequencies were decreased with CFVFB vs. SB at 1-2 oral feeding/day; only that of suction was reduced at 6-8 oral feedings/day. No group differences in suction amplitude and burst duration were observed. We speculate that oral feeding performance improves without significant change in sucking effort with a CFVFB vs. SB. In addition, we have shown that VLBW infants can tolerate faster milk flow than currently presumed. Finally, the use of a CFVFB may reduce energy expenditure as it enhances feeding performance without increasing sucking effort.

The transition to oral feeding in low-risk premature infants: relation to infant neurobehavioral functioning and mother-infant feeding interaction

BACKGROUND

The achievement of oral feeding is a critical task for the premature infant-mother dyad, yet neurobehavioral and relational factors associated with feeding difficulties of low-risk premature infants during hospitalization are not well understood.

AIM

To examine the relations between infant neurobehavioral functioning, the transition to oral feeding, and the emerging mother-infant feeding relationship in premature infants.

STUDY DESIGN AND SUBJECTS

Ninety-seven low-risk premature infants (birth weight>1000 g; gestational age>30 weeks) and their mothers were followed at the NICU. Neurobehavioral functioning was assessed with the Rapid Neonatal Neurobehavioral Assessment Procedure.

OUTCOME MEASURES

The duration of the transition to oral feeding and specific feeding difficulties during the transition were assessed. Infant feeding robustness, suck and milk transfer rates, and maternal adaptability, affect, intrusiveness and distractibility were coded from videotaped mother-infant feeding interactions prior to discharge from the NICU.

RESULTS

Thirty percent of the infants presented feeding difficulties during the transition to oral feedings. Infants with abnormal neurobehavioral functioning (37% of the cohort) showed more feeding difficulties, slower suck rates, and lower feeding robustness, and their mothers displayed less adaptive and more intrusive behavior. Maternal intrusiveness was related to lower feeding robustness and to lower suck and milk transfer rates. Neurobehavioral functioning and maternal feeding behavior predicted feeding robustness.

CONCLUSIONS

Less intact neurobehavioral functioning in the neonatal period is related to difficulties during the transition to oral feeding and to less optimal early mother-infant feeding interactions. Low-risk premature infants with poor neurobehavioral functioning should receive special attention and care.

Nutritive sucking pattern--from very low birth weight preterm to term newborn

The contribution of maturation and stimulation to the development of oral feeding was investigated, with two main objectives: (1) to analyze the nutritive sucking pattern of very-low-birth-weight newborns from their first oral feeding to the acquisition of independent oral feeding, and (2) to compare the nutritive sucking patterns of these babies, after feeding autonomy, with healthy term newborns.

METHODS

Two groups were considered for analysis. Group 1: N=15 Very-Low-Birth-Weight (VLBW), gestacional age (GA)=28.15+/-1.5, birth weight (BW)=1178.3+/-174.4. The intervention program began at 30.19+/-1.52 weeks GA. Group 2: N=25 term newborns, healthy, GA=39.04+/-1.2, BW=3370.42+/-310.76. Repeated measures of the following variables were taken (weekly for group 1): suction efficacy (SEF), rhythm of milk transfer (RMT), suctions, bursts and pauses. Group 2 was analysed only once between the 2nd and 5th day of life.

RESULTS

Group 1 has revealed a minimal suction number at 32 GA weeks (82+/-77.6) and maximal suction number at 36-37 GA weeks (162.7+/-60.7). The number of sucks seemed to be dependent of weight (p=0.005), duration of intervention (p=0.001) and chronological age (p=0.000). Significant statistical effects of gestational age were not observed (p=0.904). Sucks in bursts represented 77% at the beginning of oral feeding (32 weeks GA), and 96% at 33 weeks GA, remaining constant thereafter. The number of sucks and bursts increased with GA and weeks of feeding. The mean duration of the pauses decreased from first to fourth week of feeding (week1=14.1+/-9.1 and week4=6.4+/-1.4 s). The sucking efficacy (SEF) was better explained by weight (p=0.000), number of sucks in 5 min (p=0.025) and chronological age (p=0.044). Gestational age (p=0.051) and nutritive intervention duration (NDI) (p=0.110) did not contribute to explain SEF. Despite the observation of significant statistical differences between groups regarding GA (35.9/39.08; p=0.00), chronological age (53.3/2.5; p=0.00) and weight (1875/3360; p=0.00), the nutritive suction pattern was not statistically different between groups after feeding autonomy.

CONCLUSION

in VLBW oral feeding before 32 weeks GA allows the attainment of a mature nutritive suction pattern before term (37-40 weeks). Experience seems to be one of the influencing factors in the change of the nutritive suction pattern.

Tongue movement and intra-oral vacuum in breastfeeding infants

OBJECTIVE

The mechanism by which the breastfeeding infant removes milk from the breast is still controversial. It is unclear whether the infant uses predominantly intra-oral vacuum or a peristaltic action of the tongue to remove milk from the breast. The aim of this study was to use ultrasound to observe movements of the tongue during breastfeeding and relate these movements to both milk flow and simultaneous measurements of intra-oral vacuum.

METHODS

Submental ultrasound scans of the oral cavity of 20 breastfed infants (3-24 weeks old) were performed during a breastfeed. Intra-oral vacuums were measured simultaneously via a milk-filled supply line (SNS) connected to a pressure transducer.

RESULTS

Vacuum increased during the downward motion of the posterior tongue and at the same time milk flow and milk ducts in the nipple was observed. Peak vacuum (-145+/-58 mmHg) occurred when the tongue was in the lowest position.

CONCLUSIONS

Ultrasound imaging demonstrated that milk flow from the nipple into the infant's oral cavity coincided with both the lowering of the infants tongue and peak vacuum. Therefore vacuum is likely to play a major role in milk removal from the breast.

Maturation of oral feeding skills in preterm infants

AIM

Safe and successful oral feeding requires proper maturation of sucking, swallowing and respiration. We hypothesized that oral feeding difficulties result from different temporal development of the musculatures implicated in these functions.

METHODS

Sixteen medically stable preterm infants (26 to 29 weeks gestation, GA) were recruited. Specific feeding skills were monitored as indirect markers for the maturational process of oral feeding musculatures: rate of milk intake (mL/min); percent milk leakage (lip seal); sucking stage, rate (#/s) and suction/expression ratio; suction amplitude (mmHg), rate and slope (mmHg/s); sucking/swallowing ratio; percent occurrence of swallows at specific phases of respiration. Coefficients of variation (COV) were used as indices of functional stability. Infants, born at 26/27- and 28/29-week GA, were at similar postmenstrual ages (PMA) when taking 1-2 and 6-8 oral feedings per day.

RESULTS

Over time, feeding efficiency and several skills improved, some decreased and others remained unchanged. Differences in COVs between the two GA groups demonstrated that, despite similar oral feeding outcomes, maturation levels of certain skills differed.

CONCLUSIONS

Components of sucking, swallowing, respiration and their coordinated activity matured at different times and rates. Differences in functional stability of particular outcomes confirm that maturation levels depend on infants' gestational rather than PMA.

Infants with bronchopulmonary dysplasia suckle with weak pressures to maintain breathing during feeding

OBJECTIVE

Preterm infants with bronchopulmonary dysplasia often demonstrate sucking difficulties. The aim of this study was to determine whether the severity of bronchopulmonary dysplasia affects not only coordination among suck-swallow-respiration but also sucking endurance and performance itself.

PATIENTS AND METHODS

Twenty very low birth weight infants were studied. Infants with anomalies or intraventricular hemorrhage were excluded from the evaluation. Subjects were divided into 3 groups: no bronchopulmonary dysplasia (7 infants), bronchopulmonary dysplasia without home oxygen therapy (7 infants), and bronchopulmonary dysplasia with home oxygen therapy (6 infants). In addition to sucking efficiency, pressure, frequency, duration, and duration of sucking burst, length of deglutition apnea, number of swallows per burst, and respiratory rate were also measured during bottle-feeding at 40 weeks' postmenstrual age. In addition, PCO2 and oxygen saturation were measured at rest and during bottle-feeding.

RESULTS

Infants with severe bronchopulmonary dysplasia demonstrated not only the lowest sucking pressure and sucking frequency, shortest sucking burst duration, and lowest feeding efficiency but also the lowest frequency of swallows during the run and the longest deglutition apnea. The respiratory rate was highest, and the decrease in oxygen saturation was largest, in infants with severe bronchopulmonary dysplasia.

CONCLUSIONS

Feeding problems depend on the severity of bronchopulmonary dysplasia. Infants with bronchopulmonary dysplasia demonstrated not only poor feeding coordination but also poor feeding endurance and performance.

Cue-based oral feeding clinical pathway results in earlier attainment of full oral feeding in premature infants

OBJECTIVE

To study whether a cue-based clinical pathway for oral feeding initiation and advancement of premature infants would result in earlier achievement of full oral feeding.

STUDY DESIGN

Age of achievement of full oral intake was compared for two groups of preterm infants; a prospective study group vs historic cohort controls. Study infants had oral feedings managed by nurses using a clinical pathway that relied on infant behavioral readiness signs to initiate and advance oral feedings. Controls had oral feedings managed by physician orders.

RESULT

Fifty-one infants (n=28 study and n=23 control) were studied. Gender distribution, gestational age, birth weight and ventilator days were not different between groups. Study infants reached full oral feedings 6 days earlier than controls (36+/-1 3/7 weeks of postmenstrual age (PMA) vs 36 6/7+/-1 4/7 weeks of PMA, P=0.02).

CONCLUSION

The cue-based clinical pathway for oral feeding initiation and advancement of premature infants resulted in earlier achievement of full oral feeding.

Relationship of the first suck burst to feeding outcomes in preterm infants

OBJECTIVE

This study examined the relationship between the number of sucks in the first nutritive suck burst and feeding outcomes in preterm infants. The relationships of morbidity, maturity, and feeding experience to the number of sucks in the first suck burst were also examined.

METHODS

A non-experimental study of 95 preterm infants was used. Feeding outcomes included proficiency (percent consumed in first 5 min of feeding), efficiency (volume consumed over total feeding time), consumed (percent consumed over total feeding), and feeding success (proficiency >or=0.3, efficiency >or=1.5 mL/min, and consumed >or=0.8). Data were analyzed using correlation and regression analysis.

RESULTS AND CONCLUSIONS

There were statistically significant positive relationships between number of sucks in the first burst and all feeding outcomes-proficiency, efficiency, consumed, and success (r=0.303, 0.365, 0.259, and tau=0.229, P<.01, respectively). The number of sucks in the first burst was also positively correlated to behavior state and feeding experience (tau=0.104 and r=0.220, P<.01, respectively). Feeding experience was the best predictor of feeding outcomes; the number of sucks in the first suck burst also contributed significantly to all feeding outcomes. The findings suggest that as infants gain experience at feeding, the first suck burst could be a useful indicator for how successful a particular feeding might be.

Does the choice of bottle nipple affect the oral feeding performance of very-low-birthweight (VLBW) infants?

BACKGROUND

There is a continuous debate regarding the best bottle nipple to be used to enhance the bottle-feeding performance of a preterm infant.

AIM

To verify that feeding performance can be improved by using the bottle nipple with the physical characteristics that enhance infants' sucking skills.

METHODS

Ten "healthy" VLBW infants (941+/-273 g) were recruited. Feeding performance was monitored at two time periods, when taking 1-2 and 6-8 oral feedings/d. At each time and within 24 h, performance was monitored using three different bottle nipples offered in a randomized order. Rate of milk transfer (ml/min) was the primary outcome measure. The sucking skills monitored comprised stage of sucking, suction amplitude, and duration of the generated negative intraoral suction pressure.

RESULTS

At both times, infants demonstrated a similar rate of milk transfer among all three nipples. However, the stage of sucking, suction amplitude, and duration of the generated suction were significantly different between nipples at 1-2, but not 6-8 oral feedings/d.

CONCLUSION

We did not identify a particular bottle nipple that enhanced bottle feeding in healthy VLBW infants. Based on the notion that afferent sensory feedback may allow infants to adapt to changing conditions, we speculate that infants can modify their sucking skills in order to maintain a rate of milk transfer that is appropriate with the level of suck-swallow-breathe coordination achieved at a particular time. Therefore, it is proposed that caretakers should be more concerned over monitoring the coordination of suck-swallow-breathe than over the selection of bottle nipples.

Does the choice of bottle nipple affect the oral feeding performance of very-low-birthweight (VLBW) infants?

BACKGROUND

There is a continuous debate regarding the best bottle nipple to be used to enhance the bottle-feeding performance of a preterm infant.

AIM

To verify that feeding performance can be improved by using the bottle nipple with the physical characteristics that enhance infants' sucking skills.

METHODS

Ten "healthy" VLBW infants (941+/-273 g) were recruited. Feeding performance was monitored at two time periods, when taking 1-2 and 6-8 oral feedings/d. At each time and within 24 h, performance was monitored using three different bottle nipples offered in a randomized order. Rate of milk transfer (ml/min) was the primary outcome measure. The sucking skills monitored comprised stage of sucking, suction amplitude, and duration of the generated negative intraoral suction pressure.

RESULTS

At both times, infants demonstrated a similar rate of milk transfer among all three nipples. However, the stage of sucking, suction amplitude, and duration of the generated suction were significantly different between nipples at 1-2, but not 6-8 oral feedings/d.

CONCLUSION

We did not identify a particular bottle nipple that enhanced bottle feeding in healthy VLBW infants. Based on the notion that afferent sensory feedback may allow infants to adapt to changing conditions, we speculate that infants can modify their sucking skills in order to maintain a rate of milk transfer that is appropriate with the level of suck-swallow-breathe coordination achieved at a particular time. Therefore, it is proposed that caretakers should be more concerned over monitoring the coordination of suck-swallow-breathe than over the selection of bottle nipples.

Prediction of Feeding Performance in Preterm Infants

A nonexperimental study with a sample of 95 preterm infants was used to develop a model of feeding performance outcomes (proficiency, percent of prescribed volume consumed, and efficiency) using feeding readiness indicators (morbidity, maturity, behavior state at feeding start, and feeding experience). All readiness indicators were related to each other. In particular, there was a strong relationship between maturity and feeding experience. Morbidity only had an effect on efficiency; the most ill infants were less efficient feeders. Behavior state affects all feeding outcomes in a linear fashion; more awake and alert infants had better feeding performance outcomes. The effect of experience and maturity on the outcomes is more complex because of the relationship between the two. Experience has a greater effect as the infant matures, and as the infant matures, the amount of experience increases. Successful feeding requires maturity as well as experience.