Effect of decreasing target oxygen saturation on retinopathy of prematurity

Pulse Oximetry Saturation (Spo2) Monitoring in the Neonatal Intensive Care Unit (NICU): The Challenge for Providers: A Systematic Review

BACKGROUND

In the neonatal intensive care unit (NICU), maintaining an oxygenation level that avoids both hypoxemia and hyperoxemia is challenging. Pulse oximetry has become fundamental for noninvasive monitoring of saturation of peripheral oxygen (Spo2) in preterm newborns.

PURPOSE

The aim of this systematic review is to determine Spo2 target values in order to avoid hypoxemia or hyperoxemia and complications arising from these.

METHOD AND SEARCH STRATEGY

For this systematic review, articles were audited from 2010 to 2020 using the PRISMA guidelines. PubMed, MEDLINE, Google Scholar, and Scopus databases were used, and search terms were related to use of pulse oximetry in the NICU.

RESULTS

The result showed that 12 of 20 (60%) studies focused on target values but without a unanimous agreement on values, although 5 of 12 studies (41.66%) suggested a lower value target of 85% and 4 of 12 studies (33.33%) recommended 95% as the higher target value. Other authors showed no difference in the incidence of adverse events comparing different target values and focused the importance more on the fluctuation of the value than on the target value itself.

IMPLICATION FOR PRACTICE

Reaching a balance in the oxygen administration so as to avoid potential complications associated with hypoxemia or hyperoxemia is a challenge for the clinicians.

IMPLICATION FOR RESEARCH

Further studies on fluctuation of Spo2 comparing different starting targets could better clarify the role of fluctuations and the absolute target values.Video Abstract available at:https://journals.na.lww.com/advancesinneonatalcare/Pages/videogallery.aspx?autoPlay=false&videoId=49.

Improving preoperative identification of infants at risk for severe retinopathy of prematurity

OBJECTIVE

To increase preoperative identification of at-risk infants for severe Retinopathy of prematurity (ROP) to >95% by August 2016, with a secondary aim of reducing the number of infants with 100% intraoperative peripheral oxygen saturation (SpO₂) during the same time.

STUDY DESIGN

Prospective quality improvement project centered on preterm surgical infants admitted to Primary Children's Hospital (n = 41). Preoperative ROP risk identification rates were analyzed using an annotated run chart, intraoperative SpO₂ and laser intervention were compared using un-paired t test.

RESULTS

Preoperative identification of ROP risk increased from 60 to 100% and no infant was exposed to 100% SpO₂ intraoperatively during the study period. The incidence of laser intervention in this population decreased by 45% from 22 to 12% (p = 0.21).

CONCLUSION

Simplifying our preoperative handoff increased our rates of correct identification and communication ROP risk in preterm infants while decreasing exposure to 100% SpO₂.

The progress of prophylactic treatment in retinopathy of prematurity

Retinopathy of prematurity (ROP) is a retinal vascular disorder frequently found in premature infants. Different therapeutic strategies have been developed to treat ROP. However, there are still many children with ROP suffering by severe limitations in vision or even blindness. Recently, ROP has been suggested to be caused by abnormal development of the retinal vasculature, but not simply resulted by retinal neovascularization which takes about 4 to 6wk after birth in premature infants. Thus, instead of focusing on how to reduce retinal neovascularization, understanding the pathological changes and mechanisms that occur prior to retinal neovascularization is meaningful, which may lead to identify novel target(s) for the development of novel strategy to promote the healthy growth of retinal blood vessels rather than passively waiting for the appearance of retinal neovascularization and removing it by force. In this review, we discussed recent studies about, 1) the pathogenesis prior to retinal neovascularization in oxygen-induced retinopathy (OIR; a ROP in animal model) and in premature infants with ROP; 2) the preclinical and clinical research on preventive treatment of early OIR and ROP. We will not only highlight the importance of the mechanisms and signalling pathways in regulating early stage of ROP but also will provide guidance for actively exploring novel mechanisms and discovering novel treatments for early phase OIR and ROP prior to retinal neovascularization in the future.

Interventions To Prevent Retinopathy of Prematurity: A Meta-analysis

CONTEXT

The effectiveness of many interventions aimed at reducing the risk of retinopathy has not been well established.

OBJECTIVE

To estimate the effectiveness of nutritional interventions, oxygen saturation targeting, blood transfusion management, and infection prevention on the incidence of retinopathy of prematurity (ROP).

DATA SOURCES

A comprehensive search of several databases was conducted, including Medline, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus through March 2014.

STUDY SELECTION

We included studies that evaluated nutritional interventions, management of supplemental oxygen, blood transfusions, or infection reduction and reported the incidence of ROP and mortality in neonates born at <32 weeks.

DATA EXTRACTION

We extracted patient characteristics, interventions, and risk of bias indicators. Outcomes of interest were any stage ROP, severe ROP or ROP requiring treatment, and mortality.

RESULTS

We identified 67 studies enrolling 21 819 infants. Lower oxygen saturation targets reduced the risk of developing any stage ROP (relative risk [RR] 0.86, 95% confidence interval [CI], 0.77-0.97) and severe ROP or ROP requiring intervention (RR 0.58, 95% CI, 0.45-0.74) but increased mortality (RR 1.15, 95% CI, 1.04-1.29). Aggressive parenteral nutrition reduced the risk of any stage ROP but not severe ROP. Supplementation of vitamin A, E, or inositol and breast milk feeding were beneficial but only in observational studies. Use of transfusion guidelines, erythropoietin, and antifungal agents were not beneficial.

LIMITATIONS

Results of observational studies were not replicated in randomized trials. Interventions were heterogeneous across studies.

CONCLUSIONS

At the present time, there are no safe interventions supported with high quality evidence to prevent severe ROP.

Trends in retinopathy of prematurity over a 5-year period in a racially diverse population

BACKGROUND AND OBJECTIVE

Retinopathy of prematurity presents differently in developing versus developed countries, which may be due to environmental as well as racial differences.

PATIENTS AND METHODS

Retrospective chart review of infants screened for ROP at a single neonatal intensive care unit. Risk factors were reviewed. Main outcome measures were rates of plus disease or treatment-requiring ROP by race.

RESULTS

The study included 497 infants screened for ROP in an urban neonatal intensive care unit. Gestational age, birth weight, and bronchopulmonary dysplasia were independent risk factors for both plus disease and treatment-requiring ROP with type 3 multivariate analysis. Self-identified white race was also a risk factor for plus disease and treatment-requiring ROP. Race was significantly associated with maternal age, multiple births, and blood transfusions.

CONCLUSION

In the study population, white race was an independent risk factor for plus disease and ROP treatment.

The pathophysiology of retinopathy of prematurity: an update of previous and recent knowledge

Retinopathy of prematurity (ROP) is a disease that can cause blindness in very low birthweight infants. The incidence of ROP is closely correlated with the weight and the gestational age at birth. Despite current therapies, ROP continues to be a highly debilitating disease. Our advancing knowledge of the pathogenesis of ROP has encouraged investigations into new antivasculogenic therapies. The purpose of this article is to review the findings on the pathophysiological mechanisms that contribute to the transition between the first and second phases of ROP and to investigate new potential therapies. Oxygen has been well characterized for the key role that it plays in retinal neoangiogenesis. Low or high levels of pO2 regulate the normal or abnormal production of hypoxia-inducible factor 1 and vascular endothelial growth factors (VEGF), which are the predominant regulators of retinal angiogenesis. Although low oxygen saturation appears to reduce the risk of severe ROP when carefully controlled within the first few weeks of life, the optimal level of saturation still remains uncertain. IGF-1 and Epo are fundamentally required during both phases of ROP, as alterations in their protein levels can modulate disease progression. Therefore, rhIGF-1 and rhEpo were tested for their abilities to prevent the loss of vasculature during the first phase of ROP, whereas anti-VEGF drugs were tested during the second phase. At present, previous hypotheses concerning ROP should be amended with new pathogenetic theories. Studies on the role of genetic components, nitric oxide, adenosine, apelin and β-adrenergic receptor have revealed new possibilities for the treatment of ROP. The genetic hypothesis that single-nucleotide polymorphisms within the β-ARs play an active role in the pathogenesis of ROP suggests the concept of disease prevention using β-blockers. In conclusion, all factors that can mediate the progression from the avascular to the proliferative phase might have significant implications for the further understanding and treatment of ROP.

Incidence and risk factors for retinopathy of prematurity in a Brazilian reference service

CONTEXT AND OBJECTIVE

Retinopathy of prematurity (ROP) is a known cause of blindness in which diagnosis and timely treatment can prevent serious harm to the child. This study aimed to evaluate the incidence of ROP and its association with known risk factors.

DESIGN AND SETTING

Longitudinal incidence study in the neonatal intensive care unit (NICU) of Universidade Estadual de Montes Claros.

METHODS

Newborns admitted to the NICU with gestational age less than 32 weeks and/or birth weight less than 1,500 grams, were followed up over a two-year period. The assessment and diagnosis of ROP were defined in accordance with a national protocol. The chi-square test or Fisher's exact test were used to determine associations between independent variables and ROP. Analysis on the independent effect of the variables on the results was performed using multiple logistic regression.

RESULTS

The incidence of ROP was 44.5% (95% confidence interval, CI = 35.6-46.1) in the study population. The risk factors associated with the risk of developing the disease were: birth weight less than 1,000 grams (odds ratio, OR = 4.14; 95% CI = 1.34-12.77); gestational age less than 30 weeks (OR = 6.69; 95% CI = 2.10-21.31); use of blood derivatives (OR = 4.14; 95% CI = 2.99-8.99); and presence of sepsis (OR = 1.99; 95% CI = 1.45-2.40).

CONCLUSIONS

The incidence of ROP was higher than that found in the literature. The main risk factors were related to extreme prematurity.

"Oxygen with love" and diode laser treatment decreases comorbidity and avoidable blindness due to retinopathy of prematurity: results achieved in the past 12 years

AIM

To determine whether the "Oxygen with Love" (OWL) and diode laser treatment provided in a neonatal intensive care unit has reduced the risk of avoidable blindness caused by retinopathy of prematurity (ROP) over the past decade.

MATERIALS AND METHODS

A prospective observational cohort study was performed, in which 351 infants were examined for ROP. The inclusion conditions were as follows: preterm infants, birthweight <1500 g or <32 weeks' gestational age, and birth between 1 Jan 2000 to 31 August 2012. From mid-2009, the OWL program was implemented and the ventilation protocols for such infants were amended. We tested whether the incidence of unfavorable structural outcomes of ROP had decreased following these changes.

RESULTS

From 2004 to 2012, the survival rates of younger children increased (p < 0.003). From 2005 to 2012, laser treatment rather than cryotherapy was applied, and the incidence of unfavorable structural outcomes of ROP fell from 13% to 5.6% (not significant). From 2009 to 2012, the incidence of ROP decreased from 55% to 29% (p < 0.002). From 1 August 2009 to 31 August 2012, there was less need for ablative treatment for premature infants, with the rate falling from 11.81% to 3.9% (p < 0.03). This improvement was significantly associated with a reduction in the number of days of intubation (p < 0.0017), lower rates of sepsis (p < 0.003), and improvements in postnatal weight gain (p < 0.0002).

CONCLUSION

The introduction of the OWL program, together with lower rates of sepsis, improvements in postnatal weight gain, and the use of diode laser treatment, has reduced the incidence of unfavorable structural outcomes of ROP.

Effect of the oxygen saturation target on clinical characteristics of early- versus late-onset retinopathy of prematurity

PURPOSE

To investigate the relationship between postmenstrual age of onset of retinopathy of prematurity (ROP) and the need for treatment, while examining the effects of two different neonatal oxygen saturation protocols on this relationship.

METHODS

A retrospective chart review was conducted for eligible inborn infants born before and after the institution of a new oxygen protocol adjusting target oxygen saturation from 90%-99% to 85%-93%. Early versus late-onset ROP was defined as first presence of any stage disease on examination at <36 versus ≥ 36 weeks' postmenstrual age, respectively.

RESULTS

The median birth weight/postmentrual age of infants was 840 g per 26.1 weeks (early-onset ROP) versus 952.5 g per 28 weeks (late-onset ROP; P < 0.01 vs P < 0.01). ROP developed in 119 of 369 (32.2%) of high oxygen target infants, and 100 of 373 (26.8%) infants in the low-target group (P = 0.11). Cumulatively, 35 of 144 (24.3%) of early-onset and 8 of 69 (11.6%) of late-onset patients required treatment (P = 0.03). Maximal severity of disease after treatment, including retinal detachment frequency, was similar in early- and late-onset patients, independent of the oxygen protocol (P = 1.00).

CONCLUSIONS

The clinical behavior of type 1 ROP is similar in early-and late-onset disease, regardless of oxygen saturation targets. Type 1 ROP disease occurred in 11.6% of patients with late-onset ROP.

Lutein and zeaxanthin supplementation in preterm infants to prevent retinopathy of prematurity: a randomized controlled study

OBJECTIVES

Lutein and its isomer zeaxanthin (L/Z) function in the eye as antioxidant agents and blue-light filters. Our aim was to evaluate whether their administration could help decrease the occurrence of retinopathy of prematurity (ROP) in preterm infants.

METHODS

Infants with gestational age ≤32 weeks were randomly assigned to receive a daily dose of L/Z (0.14 + 0.006 mg) or placebo until discharge.

RESULTS

ROP occurrence was similar in the L/Z (11/58; 19%) and placebo (15/56; 27%) groups, as the occurrence of ROP at each stage and the need of eye surgery.

CONCLUSION

L/Z supplementation was ineffective in preventing ROP in preterm infants and did not affect the outcome at discharge of our patients.