14 - Respiratory Support, Establishment of Full Oral Feeds, and Length of Hospital Stay in Preterm Infants ≥33 Weeks Postmenstrual Age (PMA) - A Comprehensive Analysis

Poster Number: 14
Publication Number: 14.337

Anjeline Bukhari, University of Alberta, Edmonton, AB, Canada; Zahraa Dawoud, University of Calgary Cumming School of Medicine Department of Pediatrics, Calgary, AB, Canada; Selphee Tang, Alberta Health Services, Calgary, AB, Canada; Kamran Yusuf, University of Calgary, Calgary, AB, Canada; Shabih U. Hasan, University of Calgary, Calgary, AB, Canada

Background: Neonatal research has largely focused on infants born < 28 wk PMA, which comprise 5% of all preterm infants whereas 84% of preterm infants are born between 32-36 wk PMA. Studies on infant >32 wk PMA have either comprised of small number of infants or provided limited data on respiratory support, oral-feeding and/or variables affecting the length of stay (LOS). Such data are critically needed for improving outcomes and parental counseling.

Objective:
To ascertain the perinatal and neonatal clinical variables that lead to longer hospital stay.
To investigate the impact of PMA on the type and duration of respiratory support and achieving feeding milestones.

Design/Methods: Study population included 33-36 wk PMA infants (n=1,209), born between 2016-2021 and admitted to the tertiary care NICU at Foothills Medical Centre, Calgary, Canada. Infants with chromosomal disorders and major anomalies were excluded. Maternal and infant demographics, respiratory support, initiation of enteral and oral feeds, gavage-free oral feeds and LOS were extracted from electronic medical records and/or bedside charts. Stats analysis: For each PMA, the shorter (< median) and longer ( >median) LOS groups were compared using the Chi-square or Fisher’s exact test for categorical variables, and t-test or Mann-Whitney U test for continuous variables. Logistic regression was used to explore the characteristics, contributing to longer LOS.

Results: Of 1,209 infants assessed for eligibility, 1,027 (85%) met the inclusion criteria. The Median (IQR) LOS at 33 (n=199), 34 (n=305), 35 (n=299) and 36 (n=224) wk PMA was 22 (10), 16 (8), 12 (6) and 10 (8) d, respectively. Maternal characteristics (diabetes, hypertension, smoking, antenatal glucocorticoids or mode of delivery) had no significant effect on LOS. Within each PMA, lower birthweight, SGA, multiple births, outborn vs. inborn, acuity scores, initiation and achievement of oral feeds, and transfer to an out-of-town NICU were associated with longer LOS (< P 0.04; Table 1 A and B). Respiratory support at 33-35 wk PMA delayed achieving full oral feeds and discharge home (P < 0.05). Excluding the variables in the causal pathway, the variables for longer LOS were specific to various PMA (P < 0.04; OR & 95% CI in Table 2).Conclusion(s):  This is one of the largest and most comprehensive studies that provides the PMA-specific infant characteristics and clinical variables associated with increased LOS. These data may help with health care resource allocation and PMA-specific care planning, and importantly counseling the parents about the anticipated discharge day from the hospital.
Table 1 A.Infant Characteristics Associated with Shorter and Longer (Median; IQR) Length of Stay at Post-menstrual Age (PMA) of 33 and 34 weeks.
Table 1 BInfant Characteristics Associated with Shorter and Longer (Median; IQR) Length of Stay at Post-menstrual Age (PMA) of 35 and 36 weeks.