Effects of Oropharyngeal Colostrum Administration in Premature Infants on Late-Onset Sepsis, Necrotizing Enterocolitis, and Length of Hospital Stay

Abstract

Late-onset sepsis and necrotizing enterocolitis are major causes of morbidity and mortality in preterm infants, particularly those born at a gestational age of less than 32 weeks.The high susceptibility of this population is largely attributable to the immaturity of their immune and gastrointestinal systems. The underdevelopment of both innate and adaptive immunity further limits preterm infants’ ability to mount an effective response to microbial invasion and inflammatory processes. Late-onset sepsis is defined as a bloodstream infection occurring after 72 hours of life and is commonly associated with prolonged hospitalization and higher healthcare costs.Similarly, necrotizing enterocolitis is a serious inflammatory disease of the intestine characterized by intestinal inflammation, necrosis, and possible perforation, which may result in life-threatening complications and long-term sequelae, including short bowel syndrome, growth failure, and neurodevelopmental impairment. These conditions also lead to prolonged hospital stays and increased healthcare expenditures. Colostrum, the first milk produced by mothers after delivery,is rich in immunological components, including immunoglobulins, cytokines, growth factors,lactoferrin, and other bioactive substances that support immune protection and intestinal development. However, preterm infants often cannot tolerate enteral feeding during the early postnatal period due to gastrointestinal immaturity and clinical instability, which limits their direct intake of maternal milk. Oropharyngeal colostrum administration, administered by dabbing on the cheek pouch, allows infants to receive immune substances, which are absorbed through the oral mucosa-associated lymphoid tissue. They play crucial roles in pathogen destruction,anti-inflammatory processes, growth inhibition, and reducing bacterial adherence in both respiratory and gastrointestinal systems, thereby reducing the incidence of late-onset sepsis and necrotizing enterocolitis in preterm infants.

This descriptive retrospective study aimed to investigate the effects of oropharyngeal colostrum administration in preterm infants on late-onset sepsis, and length of hospital stay. The study employed a pathophysiological framework emphasizing the immune system of preterm infants. The sample consisted of 276 preterm infants with a gestational age of less than 32 weeks,admitted to a tertiary hospital in Bangkok, Thailand, between January 2017 and December 2022.Participants were purposively selected based on the following inclusion criteria: 1) the mother had no medical contraindications for breastfeeding, 2) the mother had no history of substance abuse or HIV infection, 3) the infant was admitted to the ward within 24 hours of birth, and 4)the infants received 0.2 mL of oropharyngeal colostrum every 3 hours from birth until 144 hours (6 days) of age. The sample was divided into two groups of 138 infants each: those who received oropharyngeal colostrum administration before 72 hours of age and those who received it after 72 hours of age. Data were collected from medical records using a maternal and preterm infant data collection form. General data were analyzed using descriptive statistics. The incidence of late-onset sepsis and necrotizing enterocolitis was compared using chi-square tests, while differences in the length of hospital stay were analyzed using the Mann–Whitney U test due to the non-normal distribution of the data. Statistical significance was determined at a p-value of less than .05.

The study findings revealed that in the group receiving oropharyngeal colostrum administration before 72 hours of age, 91 infants (65.94%) developed late-onset sepsis, 42 infants (30.43%) developed necrotizing enterocolitis, and the mean length of hospital stay was 64.20 days (SD = 30.59). Among the group receiving oropharyngeal colostrum after 72 hours of age, 85 infants (61.59%) developed late-onset sepsis, 54 infants (39.13%) developed necrotizing enterocolitis, and the mean length of hospital stay was 62.10 days (SD = 28.51).Comparison of late-onset sepsis, necrotizing enterocolitis, and length of hospital stay between the two groups revealed no statistically significant differences. The findings of this study suggest that the timing of oropharyngeal colostrum administration, before or after 72 hours of life, did not significantly affect the incidence of late-onset sepsis, necrotizing enterocolitis, or length of hospital stay among preterm infants. Although the study results showed no statistically significant difference between oropharyngeal colostrum administration before and after 72 hours of age and the incidence of late-onset sepsis, necrotizing enterocolitis, or the length of hospital stay in premature infants, this may be due to other complication factors such as maternal antenatal history,neonatal hypoxia, and the increase in milk supply and osmolarity received by premature infants each day. Therefore, additional research is needed to more comprehensively assess the effectiveness of oropharyngeal colostrum administration on health outcomes in preterm infants. Future prospective multicenter studies are recommended to further examine the long-term impact of oropharyngeal colostrum administration and to determine the optimal timing and protocols for improving health outcomes of premature infants. The findings from this study can serve as a guideline for enhancing immune function in premature infant care and improving the efficiency of nursing practices.

Keywords: Late-onset sepsis, Length of hospital stay, Necrotizing enterocolitis, Oropharyngeal colostrum administration, Premature infants

Author Contributions:
PS: Conceptualization, Method and design, Data collection, analysis, and interpretation, writing-original draft preparation, Revised manuscript
TD: Conceptualization, method and design, data analysis and interpretation, Writing-review and editing the manuscript, Corresponding with editor-in-chief
JP: Conceptualization, Method and design, Data interpretation, Revising manuscript