The optimization of home oxygen weaning in premature infants trial: Design, rationale, methods, and lessons learned

Frequent hypoxemia found in infants with bronchopulmonary dysplasia after weaning home oxygen

OBJECTIVE

Parental reports and brief clinical examinations are the primary information used to assist clinicians in weaning home supplemental oxygen in infants with bronchopulmonary dysplasia (BPD). Recorded nocturnal oximetry provides an objective assessment of hypoxemia; however, it is unknown if it identifies clinically undetected hypoxemia in the home setting. Our objective was to determine if nocturnal oximetry can identify unreported hypoxemia in infants with BPD who appear ready to wean from supplemental oxygen.

STUDY DESIGN

We conducted a retrospective chart review of infants born <32 weeks gestation with BPD who were discharged to home receiving supplemental oxygen and completed recorded nocturnal oximetry in room air during an 18-month period. Abnormal oximetry was defined as >5 min with SpO₂  < 90% and/or an oxyhemoglobin desaturation index (ODI4) >5. Comparative analysis of patients with normal and abnormal overnight oximetry was performed using Fisher Exact and Wilcoxon signed-rank test.

RESULTS

Thirty-five former premature infants completed nocturnal oximetry at 5.8 (3.4-8.3) months corrected age. Nocturnal oximetry was abnormal as defined in 67% of the cohort (n = 21). Five percent of patients were hypoxemic, 52% had frequent desaturation events, and 43% had both. No significant differences existed in neonatal characteristics between patients with normal and abnormal studies.

CONCLUSIONS

Nocturnal oximetry was abnormal in the majority of infants with BPD who were otherwise clinically ready to wean from oxygen support, suggesting that recorded home oximetry could be a feasible and useful tool to evaluate for otherwise clinically unapparent nocturnal hypoxemia in patients with BPD.

Does recorded oximetry utilizing a consensus-based algorithm compare to polysomnography in discontinuing home oxygen therapy in premature infants?

BACKGROUND

Approximately a third of all extremely preterm infants diagnosed with bronchopulmonary dysplasia will require home oxygen therapy (HOT). Lack of consensus-based guidelines has led to significant variability in outpatient HOT management in the United States. A common assessment performed before discontinuing oxygen is a formal polysomnogram (PSG). PSGs are potentially undesirable due to cost, lack of convenient access, and parental stress, so alternative testing to determine the optimal timing of safe oxygen discontinuation are needed.

METHODS

We compared nocturnal recorded home oximetry (RHO) with PSG data in a cohort of patients from the RHO trial for patients who had recordings performed simultaneously to or within 24 h of their PSG. The RHO trial was a randomized, unblinded, multi-center trial comparing two oxygen management strategies. Parameters of oxygenation were compared between PSG and RHO, and nonoximegtry findings from the PSG that changed clinical management were identified.

RESULTS

A total of 53 infants randomized to obtain a PSG as part of the RHO trial (55%) completed a PSG, and of those, 32 (64%) completed both a PSG with comparison RHO. There were more white infants in both groups than other races and ethnicities. Bland-Altman analysis showed a strong agreement of oxygen saturation time below 90% SpO₂ between PSG and RHO results (slope = 1.014, p = 0.24). Results agreed in 96% of cases.

CONCLUSION

RHO is a safe and effective alternative to PSG to assist in determination of discontinuing HOT in infants with BPD without other risks for sleep-disordered breathing.

Transmitted Home Oximetry and Duration of Home Oxygen in Premature Infants

OBJECTIVES

To determine if a home oxygen therapy (HOT) management strategy that includes analysis of recorded home oximetry (RHO) data, compared with standard monthly clinic visit assessments, reduces duration of HOT without harm in premature infants.

METHODS

The RHO trial was an unmasked randomized clinical trial conducted in 9 US medical centers from November 2013 to December 2017, with follow-up to February 2019. Preterm infants with birth gestation ≤37 + 0/7 weeks, discharged on HOT, and attending their first pulmonary visit were enrolled. The intervention was an analysis of transmitted RHO between clinic visits (n = 97); the standard-care group received monthly clinic visits with in-clinic weaning attempts (n = 99). The primary outcomes were the duration of HOT and parent-reported quality of life. There were 2 prespecified secondary safety outcomes: change in weight and adverse events within 6 months of HOT discontinuation.

RESULTS

Among 196 randomly assigned infants (mean birth gestational age: 26.9 weeks; SD: 2.6 weeks; 37.8% female), 166 (84.7%) completed the trial. In the RHO group, the mean time to discontinue HOT was 78.1 days (SE: 6.4), compared with 100.1 days (SE: 8.0) in the standard-care group (P = .03). The quality-of-life scores improved from baseline to 3 months after discontinuation of HOT in both groups (P = .002), but the degree of improvement did not differ significantly between groups (P = .75).

CONCLUSIONS

RHO was effective in reducing the duration of HOT in premature infants. Parent quality of life improved after discontinuation. RHO allows physicians to determine which infants can be weaned and which need prolonged oxygen therapy between monthly visits.

Utilization trends of respiratory medication in premature infants discharged on home oxygen therapy

BACKGROUND

Roughly half of all extremely preterm infants will be diagnosed with bronchopulmonary dysplasia (BPD), and a third will be discharged on home oxygen therapy (HOT). To date, there have been no studies that have examined the relationship between respiratory medication utilization in infants with BPD on HOT.

METHODS

The recorded home oximetry trial was a multicenter, randomized trial comparing two home oxygen management strategies in premature infants. Infants were enrolled at first outpatient pulmonary or neonatal intensive care unit (NICU) follow-up visit with a pulmonary component. Respiratory medication prescriptions and dosage were collected from time of enrollment through 6 months after HOT discontinuation. Patients were seen monthly while on HOT and at 1, 3, and 6 months after successful discontinuation.

RESULTS

During protocol visits, 174 (89%) infants had respiratory medications documented. Respiratory medication use was higher at initial follow-up visit compared with NICU discharge and decreased at the final 6-month follow-up visit. Infants who received inhaled steroids (IS) before weaning had mean HOT duration of 138 days (range: 24-562 days); infants who received IS after weaning had shorter mean HOT duration (55 days, range: 21-264). In time-to-event analysis the no IS group and the postwean group differed significantly (χ²₁  = 8.1; P = .004). NICU clinics gave a total of 35 prescriptions to 43 patients, an average of 0.8 per patient, while the pulmonary clinics gave 837 prescriptions to 153 patients, or 5.5 per patient (P < .0001).

CONCLUSION

Respiratory prescribing patterns for infants on HOT are highly variable. Utilization of IS was not associated with shorter duration of HOT.