INTRODUCTION:

Every year almost 15 million babies are born preterm globally of which three and half million babies are born premature (born before 37 completed weeks of gestation) in India, accounting for almost 13% of births in the country.^1,2 Prematurity related morbidities lead to oral feeding problems, among 30-40% of preterm approximately. These difficulties occur due to hypotonia, immature oro-motor control, and lack of coordination in sucking, swallowing, and breathing. Oral-motor function, swallowing, and breathing involve cerebral and brainstem pathways which are critical development during mid to late gestation and continue up to the first year of postpartum. In the last 6-8 weeks of gestation, one-third of brain growth occurs, thus preterm born before 32 weeks have 35% less brain volume than term babies.

Preterms commonly have difficulty coordinating the suck-swallow- breath reflex before 34 weeks postpartum due to their neurological immaturity and other medical issues. Studies have shown that median breastfeeding duration among preterm babies is only 4 months and difficulties in oromotor control persist among them even in adolescence without any speech-sound disorder.^3,5

Preterm neonates are provided assistance to improve their feeding e.g. nonnutritive sucking (NNS), suck training, oral support during feeds, cue-based feeding, oromotor stimulation (OMS). Oromotor stimulation or oral motor stimulation is part of assisting in the development of oral feeding skills.^6,13

Problems of oral feeding in preterm neonates:

Preterm neonates might face certain problems while oral feeding is attempted such as, weak, irregular rooting reflexes and sucking, inverted lower lips drew inward during breastfeeding, biting pattern, increased perioral muscle tone, hypertonic tongue.^6,7 In later life, preterms may show signs of swallowing disorders requiring specialist's attention such as incoordination between sucking and swallowing, weak feeding, alterations in breathing or apnea during the meal, excessive gagging or frequent coughing during the meal, dysphagia, marked irritability, nasal regurgitation, and lethargy during the meal, feeding time more than 30–40 min, delay in unexplained refusal of food, undernutrition, craniofacial anomalies and failure to thrive, persisting drooling beyond 5 years.^8-10

What is oromotor stimulation?

It is a scientific, sequential measure in which patterned stimulation is provided to perioral and intraoral muscular structures for strengthening them, thus facilitating normal physiologic feeding patterns.

History of oromotor stimulation:

· 1970's: Speech-Language Pathologists started working with the occupational therapist, physiotherapist, and other professionals. The clinical idea of utilizing oral motor therapy in schools, hospitals, and clinics started in this decade through the exchange of ideas.

· In 1977 a three days conference was conducted on "Oral-motor function and dysfunction in children", which was perhaps the beginning of oral-motor therapy.

· 1993 onwards research articles by the speech-language pathologists and occupational therapists came in the area of oral motor therapy in preterm neonates were published.

· In 2008, the first attempt was made by a nurse, Dr. Brenda Knoll Lessen to apply the oromotor therapy in the care of preterm neonates.

Purpose of oromotor stimulation:

Oromotor stimulation when provided to preterm at least 5-15 minutes before feeding,

· Stretches, improves the tone and length of facial muscles.

· Improves flexion of the lips for mouth closure and puckering.

· Stimulation to the tongue changes the movement of the tongue.

· Reduces pauses in sucking thus improves the frequency of sucking.

· Increases rate and volume of intake during feeds.

· Reduces transition time to exclusive breastfeeding.

Indications of oromotor stimulation in neonates:

The literature shows that oromotor stimulation can be provided to,

· Preterm neonates born at the gestational age of <29 weeks and it can be until and unless effective oral feeding is achieved,

· Neonates showing dysfunctional sucking, swallowing, and breathing coordination irrespective of their gestational age

· Neonates with existing brain damage due to birth asphyxia, intraventricular hemorrhage, or other clinical causes.

· Neonates at risk of being deprived of oral feeding due to various clinical co-morbidities e.g. congenital heart disease at early neonatal life, severe congenital anomalies leading to NPO status, etc.

Effect of oromotor stimulation among preterm neonates:

Prolonged oral feeding difficulties increases medical costs, feeding aversion, and increases maternal stress leading to poor maternal and infant reunion. But there is no direct tool to measure the oral feeding readiness among preterms and research is needed in this area to establish an evidence base for the clinical utility of instruments and implementing the use of them to assess feeding readiness in the preterm infant population.^11-12

Existing literature shows that oromotor stimulation, when administered to the preterm neonates they reach, first oral feeding earlier, have improved sucking frequency, better feeding performance in terms of overall intake and rate of milk transfer, shorter transition to independent oral feeding, better daily weight gain, earlier transition from spoon-feeding to breastfeeding, a shorter duration of hospital stay, , better score in Infanib (the instrument used for assessment of early motor development) than the control group.^13-16

Prereqisites for oromotor stimulation of preterm babies:

There is no single standardized procedure for providing oromotor stimulation to neonates. Various schools of thought are present with varying practices. But initially, before applying any method it should be considered that, the neonate is placed in a supine or side-lying position and has to be performed at least 10-20 mins before feeding, so that aspiration of food doesn't occur due to gag reflex.^14-19 The pre-requisites for prefeeding oromotor stimulation for preterms are as follows,

· Adequate information must be provided to the parents regarding the application of oromotor therapy, its benefits, and its adverse reactions if any. Oromotor stimulation when applied by parents (following a training programme) it tend to be effective as shown in the studies.²³

· Continuous monitoring of vital signs to be done throughout the procedure especially of oxygen saturation , heart rate (so that apneic spells can be identified earlier).

· Gloved fingers should be used to prevent the spread infection to the baby even when providing non-nutritive sucking.

· If the baby doesn't tolerate the therapy then immediately discontinue it. The signs of intolerance to oromotor therapy are periods of apnea inbetween therapy, the baby seems to be drowsy, crying because of discomfort.

· There is no fixed dose of administration for this therapy but existing literature shows, that oromotor stimulation is effective whether it is applied once a day or 6 time a days.^11-14Before application of oromotor stimulation the administrator of therapy must undergo a training programme and obtain permission from the respective copyright owner.

Strategies for providing oromotor stimulation:

Oromotor stimulation is currently, provided through manual application in neonatal intensive care units. The protocol is still at the evolving stage and it lacks any fixed frequency of application. Though PIOMI (Premature Infant Oromotor Intervention) has been developed in 2008 based on scientific evidence.

Dr. Brenda Leessen, has adopted the PIOMI from the Beckman Oral Motor Intervention (BOMI). The BOMI is a 15 minutes oral motor intervention for infants, children, and adults with developmental delays having feeding difficulties. BOMI is redesigned for use in premature neonates considering their physiological requirement, safety and tolerance. PIOMI is an assisted movement of 5 minutes duration, provided to activate muscle contraction and provides movement against resistance to build strength in the oral cavity. The target areas of the mouth include cheeks, lips, gums, tongue, and palate. It is provided using a gloved finger in the mouths of premature infants of at least 29 weeks post-menstrual age (PMA) and can be provided by any direct care provider of neonates. In the following section (Table 1) depicts the complete steps of the procedure.¹⁴

Other methods of providing oromotor stimulation in neonates:

NTrainer, is an FDA approved method of providing oromotor stimulation in neonates other than manual methods. Patterned frequency-modulated oro-somatosensory stimulation is delivered via the NTrainer System through a pacifier interface. NTrainer has a pneumatic stimulator which generates a series of frequency modulated pulses (0 to 16 Hz) patterned as 6-cycle bursts followed by 2-second pause periods, which transforms the pacifier into a pulsating nipple stimulating the oral facial nerves. Studies have shown that, NTrainer is effective in reducing time to achieve full oral feeds and duration of hospitalization even in 29-30 weeks subgroup.²⁰

DISCUSSION:

Feeding a preterm baby to meet his/her body requirements is a challenge for health care professionals. Physiological immaturity makes a pretmature baby vulnerable for developing feeding difficulties. Oromotor stimulation is a method of choice for enhancing feeding ability among them. It can be provided manually by a trained health care provider or a parent. Stimulation can also be provided through mechanical methods such as NT Trainer. In all cases continuous monitoring of vital signs is mandatory to identify any sign of intolerance and the procedure should be applied consistently to achieve desirable results.

Although prefeeding oromotor stimulation is a rapidly growing field of interest, most of the studies are done only on haemodynamically stable preterm babies.^14-20,23 There is still limited number of studies conducted in India on oromotor stimulation.^15-16,23 It’s effect on preterms with medical complications are till unrevealed. Thus further research studies are required in this area.

CONCLUSION:

In India use of oromotor stimulation in neonates is not a regular practice in neonatal intensive care units. Even only It is currently a growing field of interest for researchers to develop a protocol for improving oral skills in preterm babies. Oromotor stimulation is a major assistance that promotes earlier transitions to oral feeding and latching to breast, reduces hospital stay among preterm neonates. Most of the neonatal intensive care units of India practices only non-nutritive sucking to enhance oral motor function but they lack regular practice of oromotor stimulation. Thus, based on existing evidence base oromotor stimulation should be actively incorporated in regular neonatal care.

REFERENCES:

1. Lee ACC, Blencowe H, Lawn JE. Small babies, big numbers: global estimates of preterm birth. The Lancet Global Health. 2019 Jan; 7(1): Available from: https://www.thelancet.com/journals/langlo/article/PIIS2214109X (18)30484-4/fulltext. Accessed on 2020; 08; 25,

2. March of Dimes, PMNCH, Save the Children, WHO. Born Too Soon: The Global Action Report on Preterm Birth. Eds, Howson CP, Kinney MV, Lawn JE. Geneva: World Health Organization, 2012.

3. Lau C. Development of infant oral feeding skills: what do we know? Am J Clin Nutr: 2016; 06: 103, 616-21.

4. Baker M, Villela LD, Gomes S, Tovar MC, Moreira ML. Breastfeeding of preterm newborn infants following hospital discharge: follow-up during the first year of life. Ciencia and Saúde Coletiva, 2018; 04: 23(7): 2403-12, Available from: http://www.scielo.br/scielo.php?pid=S1413, Accessed on July 30, 2020

5. Northam GB, Morgan AT, Fitzsimmons S, Baldeweg T and Liégeois FJ. Corticobulbar tract injury, oromotor impairment and language plasticity in adolescents born preterm. Hum. Neurosci: 2019 Feb; 13 (45): 1-7. Available from: https://www.ncbi.nlm.nih.gov/pubmed/30837853. Accessed on Aug 27, 2020

6. Manno CJ, Fox C, Eicher PS, Kerwin ME. Early oral motor intervention for pediatric feeding problems: what when and how. JEIBI: 2005 Fall; 2(3): 145-54. Available from: https://files.eric.ed.gov/fulltext/EJ846764.pdf. Accessed on Aug 9, 2020

7. https://pdfs.semanticscholar.org/90d4/576e2bbc27adc4ab8f90c825ddb89f12de12.pdf. Accessed on Oct 9, 2019

8. Zaidi I, Thayath MN, Singh S, Sinha A. Preterm birth: a primary etiological factor for delayed oral growth and development. IJCPD: 2015 Sep; 8(3): 215-19. Available from: https://pdfs.semanticscholar.org/f0ab/f9bb6cd1213f27ebdda2dc40cbe19240f375.pdf. Accessed on July 29, 2020

9. Pedroza RMS, López LFC, Gómez KER. Description of oral-motor development from birth to six years of age. Rev. Fac. Med: 2014 Aug; 62(4): 593-604. Available from: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-00112014000400012. Accessed on July 29, 2020

10. Sanches MTC. Clinical management of oral disorders in breastfeeding. Jornal de Pediatria J Pediatr: 2004 Sep; 80(5): 155-62. Available from: https://www.ncbi.nlm.nih.gov/pubmed/15583766. Accessed on Aug 27, 2020

11. Pados BF, Park J, Estrem H, Awotwi A. Assessment tools for evaluation of oral feeding in infants younger than 6 months. Adv Neonatal Care. 2016 April; 16 (2): 143–50. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4781663/. Accessed on Aug 30, 2020.

12. Crowe L, Chang A, Wallace K. Instruments for assessing readiness to commence suck feeds in preterm infants: effects on time to establish full oral feeding and duration of hospitalisation. Cochrane Database Syst Rev. 2016; 2016(8): 1-22. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/27552522/. Accessed on Aug 30, 2020.

13. Dodrill P. Feeding difficulties in preterm infants. ICAN: Infant, Child, and Adolescent Nutrition: 2011 Dec; 3(6): 324-29. Available from: https://www.researchgate.net/publication/254080967_Feeding_Difficulties_in_Preterm_Infants. Accessed on July 28, 2020

14. Ghomia H, Yadegarib F, Soleimania F, Lessen BK, Noroozid M, Mazourie A. The effects of premature infant oral motor intervention (PIOMI) on oral feeding of preterm infants: A randomized clinical trial. Int J. Pedia Otor: 2019 Feb; 120 (4): 202-9.

15. Thakkar PA, Rohit HR, Das RR, Thakkar UP, Singh A. Effect of oral stimulation on feeding performance and weight gain in preterm neonates: a randomised controlled trial, Paediatrics and International Child Health. 2018 Sep; 1-6. Available from: https://doi.org/10.1080/20469047.2018.1435172. Accessed on Aug 27, 2020

16. Arora K. et al. Prefeeding oromotor stimulation program for improving oromotor function in preterm infants – a randomized controlled trial. Indian Pediatrics. 2018 Aug; 55(1): 675-78

17. Hasanah O, Novayelinda R, Deli H. The effect of oromuscular stimulation on neonate latch score. Enferm Clin. 2019 Feb; 29(1): 46-48. Available from: https://www.researchgate.net/publication/330858665_The_effect_of_oromuscular_stimulation_on_neonate_latch_score. Accessed on Apr 2, 2020

18. Khalessi N, Nazi S, Shariat M, Saboteh M, Farahani Z. The effects of pre-feeding oral stimulations and non-nutritive sucking on physical growth and independent oral feeding of preterm infants. Iran J Pediatr. 2015 June; 25(3): 1-5

19. Yang C. et al. Clinical significance of oral motor intervention on the prognosis of early premature infant. Chin Crit Care Med. 2019 Feb;31(2): 150-54. Available from: https://www.ncbi.nlm.nih.gov/pubmed/30827300. Accessed on Aug 8, 2020

20. Song D, Jegatheesan P, Nafday S, Ahmad KA, Nedrelow J, Wearden M, et al. Patterned frequency-modulated oral stimulation in preterm infants: A multicenter randomized controlled trial. PLoS ONE. 2019 Feb; 14(2): 1-15. Available from: https://www.ncbi.nlm.nih.gov/pubmed/30817764. Accessed on Aug 3, 2020

21. Kirk et al. Health, nutrition, and development of children born preterm and low birth weight in rural Rwanda: a cross-sectional study. BMC Pediatrics: 2017 July; 17(3): 191-95. Available from: https://www.researchgate.net/publication/321088718_Health_nutrition_and_development_of_children_born_preterm_and_low_birth_weight_in_rural_Rwanda_A_cross-sectional_study. Accessed on July 28, 2020

22. Freitas BAC, Lima LM, Valente CFL, Priore SE, Sylvia FC. Duration of breastfeeding in preterm infants followed at a secondary referral service. Rev Paul Pediatr: 2016 Mar; 34(2): 189-196. Available from: https://docksci.com/duration-of-breastfeeding-in-preterm-infants-followed-at-a-secondary-referral-se_5a245d99d64ab20a5ec13061.html. Accessed on July 27, 2020

23. Topkar P, Metgud D, Machakanur V. Effect of follow-up home based oromotor stimulation on breastfeeding performance in preterm low-birth-weight infants: A randomized control trial. Indian J Health Sci Biomed Res: 2019; 12: 85-90

Received on 08.09.2020 Modified on 03.10.2020

Asian J. Nursing Education and Research. 2021; 11(2):169-172.

DOI: 10.5958/2349-2996.2021.00042.2

8 steps	Purpose	Duration
Cheek	Improve range of motion and strength of cheeks, and improve lip seal.	30 sec
Lip roll	Improve lip range of motion and seal.	30 sec
Lip curl or Lip stretch	Improve lip strength, range of motion, and seal.	30 sec
Gum massage	Improve range of motion of tongue, stimulate swallow, and improve suck.	30 sec
Lateral borders of tongue/ cheek	Improve tongue range of motion and strength.	15 sec
Midblade of tongue/ palate	Improved tongue range of motion and strength, and improve suck.	30 sec
Elicit a suck	Improve suck, and soft palate activation.	15 sec
Support for non- nutritive sucking	Improve suck, and soft palate activation.	2 Min