Abstract
BackgroundRespiratory rate is difficult to measure, especially in neonates who have an irregular breathing pattern. The World Health Organisation recommends a one-minute count, but there is limited data to support this length of observation. We sought to evaluate agreement between the respiratory rate (RR) derived from capnography in neonates, over 15 s, 30 s, 120 s and 300 s, against the recommended 60 s.MethodsNeonates at two hospitals in Nairobi were recruited and had capnograph waveforms recorded using the Masimo Rad 97. A single high quality 5 min epoch was randomly chosen from each subject. For each selected epoch, the mean RR was calculated using a breath-detection algorithm applied to the waveform. The RR in the first 60 s was compared to the mean RR measured over the first 15 s, 30 s, 120 s, full 300 s, and last 60 s. We calculated bias and limits of agreement for each comparison and used Bland-Altman plots for visual comparisons.ResultsA total of 306 capnographs were analysed from individual subjects. The subjects had a median gestation age of 39 weeks with slightly more females (52.3%) than males (47.7%). The majority of the population were term neonates (70.1%) with 39 (12.8%) having a primary respiratory pathology. There was poor agreement between all the comparisons based on the limits of agreement [confidence interval], ranging between 11.9 [− 6.79 to 6.23] breaths per minute in the one versus 2 min comparison, and 34.7 [− 17.59 to 20.53] breaths per minute in the first versus last minute comparison. Worsening agreement was observed in plots with higher RRs.ConclusionsNeonates have high variability of RR, even over a short period of time. A slight degradation in the agreement is noted over periods shorter than 1 min. However, this is smaller than observations done 3 min apart in the same subject. Longer periods of observation also reduce agreement. For device developers, precise synchronization is needed when comparing devices to reduce the impact of RR variation. For clinicians, where possible, continuous or repeated monitoring of neonates would be preferable to one time RR measurements.
Highlights
Respiratory rate is difficult to measure, especially in neonates who have an irregular breathing pattern
Given the high variability of the breathing pattern in neonates, there is uncertainty on whether a 60 s measurement accurately captures a rate that is reflective of the respiratory status
The primary purpose of the Evaluation of Technologies for Neonates in Africa (ETNA) platform was to establish the accuracy and feasibility of emerging continuous multiparameter monitoring devices, the EarlySense (EarlySense Ltd., Israel) an under-mattress device and the Sibel Advanced Neonatal Epidermal (ANNE) device (Sibel Inc., Evanston, IL, USA), in measuring vital signs in neonates when compared with verified reference devices [9]
Summary
Respiratory rate is difficult to measure, especially in neonates who have an irregular breathing pattern. Respiratory rate (RR), though regarded as critically important for the diagnosis and management of respiratory and non–respiratory disease, remains a difficult parameter to monitor reliably [1]. It is affected by various factors including fever, feeding, agitation as well as sleep versus awake state [2]. Given the high variability of the breathing pattern in neonates, there is uncertainty on whether a 60 s measurement accurately captures a rate that is reflective of the respiratory status. A better understanding of the impact of the duration of monitoring will guide clinicians on the utility of RR while making clinical decisions
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
