Elsevier

The Journal of Pediatrics

Volume 159, Issue 6, December 2011, Pages 900-906.e1
The Journal of Pediatrics

Original Article
Mortality Reduction by Heart Rate Characteristic Monitoring in Very Low Birth Weight Neonates: A Randomized Trial

https://doi.org/10.1016/j.jpeds.2011.06.044Get rights and content

Objective

To test the hypothesis that heart rate characteristics (HRC) monitoring improves neonatal outcomes.

Study design

We conducted a two-group, parallel, individually randomized controlled clinical trial of 3003 very low birth weight infants in 9 neonatal intensive care units. In one group, HRC monitoring was displayed; in the other, it was masked. The primary outcome was number of days alive and ventilator-free in the 120 days after randomization. Secondary outcomes were mortality, number of ventilator days, neonatal intensive care unit stay, and antibiotic use.

Results

The mortality rate was reduced in infants whose HRC monitoring was displayed, from 10.2% to 8.1% (hazard ratio, 0.78; 95% CI, 0.61-0.99; P = .04; number needed to monitor = 48), and there was a trend toward increased days alive and ventilator-free (95.9 of 120 days compared with 93.6 in control subjects, P = .08). The mortality benefit was concentrated in infants with a birth weight <1000 g (hazard ratio, 0.74; 95% CI, 0.57-0.95; P = .02; number needed to monitor = 23). There were no significant differences in the other outcomes.

Conclusion

HRC monitoring can reduce the mortality rate in very low birth weight infants.

Section snippets

Methods

Very low birth weight (<1500 g birth weight) infants at 9 hospitals were randomized to display or not to display the HRC monitor results. This was a parallel group study with one-to-one randomization. Initially, all inborn and outborn babies with birth weights <1500 g were eligible. After enrolling 257 infants, we further restricted inclusion criteria for outborn infants to include only very low birth weight infants who had been transferred to a study center at <33 weeks post-menstrual age.

Results

We screened 5995 infants for eligibility (Figure 1). A total of 3003 infants were randomized from April 2004 through May 2010. A total of 2989 infants were included in the analysis. Before unblinding and analysis, we excluded 14 randomized infants because of birth weight ≥1500 g (4 in the study group, one in the control group), error in randomization (3, all in the study group), consent withdrawn (two in the study group, one in the control group), or sustained cardiac arrhythmia (two in the

Discussion

In this large, simple randomized trial,18 we tested the hypothesis that HRC monitoring, which detects the abnormal reduced variability and transient decelerations that often precede late-onset neonatal sepsis, can improve outcomes in very low birth weight infants. The 2.3-day increase of the composite primary outcome measure of days alive and not on a ventilator in the infants whose HRC monitoring results were displayed was not statistically significant (P = .08). We found, however, a

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    Supported by National Institutes of Health (grant R01-HD48562 to J.M.) and by Medical Predictive Science Corporation, Charlottesville, VA, which provided study hardware and software for heart rate characteristics monitoring and for study data collection and management. Neither of these funding sources had any role in the design of the study, in the analysis and interpretation of the data, in the decision to submit the manuscript, or in the preparation, review, or approval of it. J.M. and D.L. have consulting agreements and equity shares in Medical Predictive Science Corporation, Charlottesville, VA. The other authors declare no conflicts of interest.

    Trial is registered at ClinicalTrials.gov (NCT00307333).

    Present address: University of Oregon Health Sciences Center, Portland, Oregon.

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