Key Messages
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The evidence indicates that non-invasive monitoring (near-infrared spectroscopy; NIRS) of oxygen in brain tissue likely does not reduce death rates or short-term brain problems for very premature babies.
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Future studies should use NIRS more consistently and look at long-term effects to get clearer answers about potential benefits.
What is near-infrared spectroscopy (NIRS)?
Near-infrared spectroscopy (NIRS) is a non-invasive tool that can be used to measure brain oxygen levels.
How might NIRS help preterm babies in the neonatal intensive care unit?
Premature babies, especially those born very early (before 32 weeks of pregnancy), often face serious health problems. These potential problems include brain damage caused by insufficient oxygen supply to the brain. Using NIRS to monitor brain oxygen levels might help doctors take action early and quickly if something goes wrong, but it is important to know whether it actually works.
What did we want to find out?
We wanted to know whether NIRS monitoring is better than regular care for protecting the brain, improving neurological (brain) development, and helping very premature babies survive better. Specifically, we were interested in the effect of NIRS on:
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death for any reason;
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neurodevelopmental problems (including cerebral palsy, serious developmental delays, blindness, and deafness) when the babies grow older (18 to 24 months);
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serious brain damage;
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chronic lung disease;
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necrotising enterocolitis (serious intestinal disease);
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severe retinopathy of prematurity (eye disease); and
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severe unwanted reactions.
What did we do?
We searched for studies that compared NIRS monitoring with no NIRS or blinded NIRS monitoring (where the treating health professionals are unaware of the brain oxygen levels so cannot make any decisions based on this information) in very preterm infants. We compared and summarised the results of the studies and rated our confidence in the evidence, based on factors such as study methods and sizes.
What did we find?
We included five studies published between 2016 and 2023 and involving 2415 very preterm babies (1191 in the NIRS group and 1224 in the no NIRS/blinded NIRS group). Babies in the no NIRS/blinded NIRS group received standard care.
What are the main results?
Evidence from five studies (with 2415 infants) shows that NIRS monitoring compared with usual care likely results in little to no difference in:
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death for any reason;
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serious brain damage;
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chronic lung disease;
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necrotising enterocolitis (serious intestinal disease); and
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severe adverse reactions.
The evidence is very uncertain about the effect of NIRS on long-term neurodevelopmental problems when babies are older, based on one study with 115 babies. NIRS monitoring likely results in little to no difference in reducing severe retinopathy of prematurity (eye disease), based on two studies with 1745 babies.
What are the limitations of the evidence?
Four of the five included studies were small, and few infants died or had serious brain injury or long-term neurodevelopmental problems. In addition, the results varied widely across the different studies. Not all studies used NIRS in the same way, which makes it hard to know if it would have the same effects for all babies across the different health centres in different countries. Finally, not all the outcomes we were interested in were clearly measured.
The results of future research could differ from the results of this review.
How up to date is this evidence?
The evidence is current to August 2025. Five relevant studies are in progress, and one of these plans to enrol 3000 babies by 2029. This large study may provide more evidence to inform our understanding of the benefits and harms of NIRS in very preterm infants.
Baca abstrak penuh
Cerebral injury and long-term neurodevelopmental impairment is common in extremely preterm infants. Cerebral near-infrared spectroscopy (NIRS) enables continuous estimation of cerebral oxygenation. This diagnostic method coupled with appropriate interventions if NIRS is out of normal range (that is cerebral oxygenation within the 55% to 85% range) may offer benefits without causing more harms. Therefore, NIRS coupled with appropriate responses to abnormal findings on NIRS needs assessment in a systematic review of randomised clinical trials and quasi-randomised studies.
Matlamat
To evaluate the beneficial and harmful effects of cerebral near-infrared spectroscopy (NIRS) monitoring versus no NIRS or blinded NIRS monitoring in very preterm infants.
Kaedah Pencarian
We searched CENTRAL, MEDLINE, Embase, CINAHL, three trial registries, and conference abstracts up to August 2025. We also checked reference lists of included studies and relevant systematic reviews.
Kriteria Pemilihan
Randomised clinical trials and quasi-randomised clinical studies comparing continuous cerebral NIRS monitoring for at least 24 hours versus blinded NIRS or versus no NIRS monitoring.
Pengumpulan Data dan Analisis
Two review authors independently selected, assessed the quality of, and extracted data from the included trials and studies. If necessary, we contacted authors for further information. We conducted assessments of risks of bias; risks of design errors; and controlled the risks of random errors with Trial Sequential Analysis. We assessed the quality of the evidence with GRADE.
Keputusan Utama
One randomised clinical trial met inclusion criteria, including infants born more than 12 weeks preterm. The trial employed adequate methodologies and was assessed at low risk of bias. One hundred and sixty-six infants were randomised to start continuous cerebral NIRS monitoring less than 3 hours after birth until 72 hours after birth plus appropriate interventions if NIRS was out of normal range according to a guideline versus conventional monitoring with blinded NIRS. There was no effect of NIRS plus guideline of mortality until term-equivalent age (RR 0.50, 95% CI 0.29 to 1.00; one trial; 166 participants). There were no effects of NIRS plus guideline on intraventricular haemorrhages: all grades (RR 0.93, 95% CI 0.65 to 1.34; one trial; 166 participants); grade III/IV (RR 0.57, 95% CI 0.25 to 1.31; one trial; 166 participants); and cystic periventricular leukomalacia (which did not occur in either group). Likewise, there was no effect of NIRS plus guideline on the occurrence of a patent ductus arteriosus (RR 1.96, 95% CI 0.94 to 4.08; one trial; 166 participants); chronic lung disease (RR 1.27, 95% CI 0.94 to 1.50; one trial; 166 participants); necrotising enterocolitis (RR 0.83, 95% CI 0.33 to 1.94; one trial; 166 participants); and retinopathy of prematurity (RR 1.64, 95% CI 0.75 to 3.00; one trial; 166 participants). There were no serious adverse events in any of the intervention groups. NIRS plus guideline caused more skin marks from the NIRS sensor in the control group than in the experimental group (unadjusted RR 0.31, 95% CI 0.10 to 0.92; one trial; 166 participants). There are no data regarding neurodevelopmental outcome, renal impairment or air leaks.
The quality of evidence for all comparisons discussed above was assessed as very low apart from all-cause mortality and adverse events: these were assessed as low and moderate, respectively. The validity of all comparisons is hampered by a small sample of randomised infants, risk of bias due to lack of blinding, and indirectness of outcomes.
Kesimpulan Pengarang
Overall, cerebral NIRS monitoring in very preterm infants likely results in little to no benefit for most measured outcomes.
Compared with conventional monitoring, cerebral NIRS monitoring in very preterm infants likely results in little to no difference in all-cause mortality at longest follow-up and in major brain injury diagnosed by brain ultrasound prior to discharge, and we are unsure about its effect on major neurodevelopmental disability in children aged 18 to 24 months. Furthermore, NIRS monitoring likely results in little to no difference in the risk of chronic lung disease at 36 weeks' gestational age, proven necrotising enterocolitis prior to discharge, severe retinopathy of prematurity prior to discharge, and severe adverse reactions prior to discharge.
Future randomised trials in very preterm infants should provide continuous NIRS monitoring from birth until cardiorespiratory stability to more accurately assess the potential benefits of the intervention. Further research is needed to understand and quantify performance differences among available NIRS devices and to evaluate their effects on long-term clinical outcomes. Few (if any) vital sign monitoring methods have demonstrated patient-relevant benefits in RCTs. For cerebral oximetry in preterm infants, trials using clinically meaningful endpoints (e.g. neurodevelopment at two years assessed with the Bayley Scales) may be infeasible due to the large sample sizes required. In this context, surrogate outcomes, such as electrophysiological markers of hypoxic brain injury, may offer a feasible alternative, provided they are rigorously validated against clinical endpoints.
Funding
This Cochrane review had no dedicated funding.
Registration
Protocol (2015): doi.org/10.1002/14651858.CD011506
Original review (2017): doi.org/10.1002/14651858.CD011506.pub2
Review update (2025): doi.org/10.1002/14651858.CD011506.pub3
