Pediatric Resident University of Kentucky College of Medicine Lexington, Kentucky, United States
Background: Major consequences of prematurity are apnea and lung disease that lead to repeated occurrences of Intermittent Hypoxemia (IH); episodic drops in blood oxygen saturation (SpO2). These chronic IH events may have a cumulative impact on neonatal outcomes. A recent study showed the severity of IH is affected by response time to FiO2 adjustment by the NICU staff. However, there is limited data on diurnal variation of IH, as well as between infants in an OBU versus SFR NICU. Objective: Assess the differences in IH between day and night shifts in an OBU versus SFR NICU. Design/Methods: Our NICU transitioned from OBU to SFR which allowed us to perform this comparison. To accurately quantify IH, SpO2 was continuously measured with high resolution research pulse oximeters (2s averaging, 1s sampling). Primary IH outcomes were defined as percent time and frequency of IH events with SpO2 < 80%. Since IH events increase with advancing postnatal age (Abu Jawdeh 2017), we assessed IH differences at three age timepoints: 7, 30, and 60 days of life (DOL) during day (7:00-18:59) and night (19:00-6:59) shift. We compared IH between day and night shifts in all infants as well as between infants in an OBU versus SFR. We used two-tailed nonparametric and paired parametric tests for these analyses. Results: A total of 130 infants were included (OBU 102, SFR 28). There were no differences in gestational age (GA) and birth weight of infants between units (OBU 26 5/7 weeks and 935g, SFR 26 5/7 weeks and 880g), all p = NS. At DOL 7, infants spent higher percent time in hypoxemia (Mean ± SEM, 2.50 ± 0.48 vs 1.37 ± 0.21, p = 0.006) and had increased IH frequency (4.77 ± 0.74 vs 3.37 ± 0.46 p = 0.035) in the day compared to night shift, especially in SFR (5.66 ± 1.74 vs 2.56 ± 0.64, p = 0.045). There were no significant differences at DOL 30 and 60. Comparing OBU to SFR, infants spent more time in hypoxemia and had higher IH frequency in SFR at multiple age timepoints (Figure).
Conclusion(s): Our results show increased IH during the day compared to night shift in the acute postnatal period, especially in SFR. Our study also suggests an association between SFR and increased IH. Higher IH in SFR may be related to delayed response to adjust FiO2 after IH, compared to OBU where multiple staff members may be available to attend to infant needs. As more hospitals are transitioning to SFR NICUs to improve parent engagement and outcomes, our findings suggest different staffing and back up models may be needed. We plan to determine if IH differences persist following staffing and model adjustments to SFR in our NICU.
.jpg)