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.


CONCLUSIONS
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.
Cunha
Manuel
M
Pediatrics Department of Hospital Fernando Fonseca, Portugal. manuelsousacunha@iol.pt
Barreiros
João
J
Gonçalves
Inês
I
Figueiredo
Helena
H