Effect of Predictable Oral Feeding on Sucking and Breathing in Preterm Infants

Rita H. Pickler, PhD, RN, PNP-BC, FAANProfessor and Nurse Scientist, Cincinnati Children’s Hospital Medical CenterAffiliate Clinical Professor, University of CincinnatiAffiliate Research Professor, Ohio State University

Barbara A. Reyna, PhD, RN, NNPNurse Practitioner, VCU Health System

Al Best, PhDAssociate Professor, Virginia Commonwealth University

Paul Wetzel, PhDAssociate Professor, Virginia Commonwealth University

Pallavi Ramnarain, PhDMarty Lewis, BS, RNVCU Health System

Brief Background

• Transition from gavage to oral feedings is a major challenge for preterm infants

• Competence at oral feeding is a criterion for hospital discharge

• Few evidence-based protocols to guide clinicians

• Potentially short and long-term effects to trial-and-error approaches to oral feeding for preterm infants

Study Aims

• The specific aim of the study was to test four approaches to oral feeding introduction and progression.– The aim of this analysis was to test the effect of the

feeding approaches on sucking and breathing in preterm infants.

Methods

• RCT– Infants randomly assigned by morbidity strata to 1 of

4 , 14 day feeding approaches– 2 groups started at 32 weeks PMA; 2 groups started at

34 weeks PMA– 1 group at each starting PMA was offered oral feedings

at each opportunity; 1 group at each starting was offered gradually increasing oral feedings

• Infants observed at oral feeding once a day for 14 days and then biweekly until discharge

Sample Characteristics

• 99 participants– 53 males; mean BW 1390 grams (590 to 2465)– 77 Black; 5 Hispanic– Morbidity measured by NMI: NMI 1=24; NMI 2= 17; NMI 3=33;

NMI 4=9; NMI 5=16

• Groups– 32 Slow: Allocated/received intervention 28/19; 15 male; 20

Black; NMI 1=6, 2=6, 3=6,4=3,5=3– 32 Max: Allocated/received intervention 28/26; 16 male; 22 Black;

NMI 1=6, 2=4, 3=10, 4=2,5=4– 34 Slow: Allocated/received intervention 27/24; 17 male; 21

Black; NMI 1=8, 2=4, 3=8, 4=2, 5=4– 34 Max: Allocated/received intervention 24/20; 10 male; 21 Black;

NMI 1=6, 2=5, 3=7, 4=2, 5=2

Why sucking and breathing?

• Crucial to fluid intake and thus feeding functioning

• Ability at one can affect functioning at the other– Breathing most likely

affected by swallowing– Swallowing most likely

affected by sucking

• Coordination could be the best reflection of skill

Sucking Characteristics and Changes

At Protocol Start At Protocol End

#Sucks* #Bursts Sucks/Burst

#Sucks #Bursts Sucks/Burst

32 Slow 76.0 22.0 3.2 192.4 26.5 7.8

32 Max 56.1 15.5 4.8 158.4 21.1 7.9

34 Slow 115.0 23.8 7.2 302.0 38.9 12.6

34 Max 193.0 30.0 8.8 224.5 37.0 6.7

* <0.05

Breathing Characteristics and Changes

At Protocol Start At Protocol End

#Breaths* #Bursts* Breaths/Bursts

#Breaths #Bursts Breaths/Bursts

32 Slow 372.9 35.9 11.5 486.4 50.8 10.1

32 Max 275.5 28.4 9.7 496.9 49.2 11.0

34 Slow 491.2 47.6 11.2 755.2 53.5 16.4

34 Max 615.9 52.9 13.5 670.9 53.1 14.2

* <0.05

Coordination of Feeding Activities

Distribution of Proportion of Feeding Time Spent in Overlapping Feeding Activities (mean = 0.58, SD = 0.186)

Distribution of Percent Overlap (mean = 12.6, SD = 12.27)

Suck-Breath Coordination

At Protocol End

%Suck %Breath %Overlap

32 Slow 35.6 39.8 14.6

32 Max 31.9 39.7 14.6

34 Slow 45.0 44.4 20.3

34 Max 29.1 37.0 7.6

Level Least Sq Mean Std Error Mean

Slow 19.375828 2.6199724 19.3758

Max 11.980633 2.4577520 11.9806

Summary of Findings

• Sucking and breathing events changed with maturity with a greater number of events and generally enhanced functioning

• Coordination at the end of the protocol showed a trend town less over lap in the later starting group with maximum experience

Conclusions

• The components of sucking and breathing during oral feedings in preterm infants changes with maturity

• The relationship or coordination of the sucking to breathing also changes with maturity although the activities of each appear to be independent of each other

• Allow infants to mature prior to initiating oral feedings may improve overall feeding performance.

Future Research

• Research is needed to further investigate the relationships between sucking and breathing activities as well as their development over time

• The effect of sucking and breathing coordination on feeding outcomes should be examined

• Interventions that support the optimal development of sucking and breathing should be considered