Has the time come to use near-infrared spectroscopy as a routine clinical tool in preterm infants undergoing intensive care?

Abstract

Several instruments implementing spatially resolved near-infrared spectroscopy (NIRS) to monitor tissue oxygenation are now approved for clinical use. The neonatal brain is readily assessible by NIRS and neurodevelopmental impairment is common in children who were in need of intensive care during the neonatal period. It is likely that an important part of the burden of this handicap is due to brain injury induced by hypoxia–ischaemia during intensive care. In particular, this is true for infants born extremely preterm. Thus, monitoring of cerebral oxygenation has considerable potential benefit in this group. The benefit, however, should be weighed against the disturbance to the infant, against the limitations imposed on clinical care and against costs. The ultimate way of demonstrating the ‘added value’ is by a randomized controlled trial. Cerebral oximetry must reduce the risk of a clinically relevant endpoint, such as death or neurodevelopmental handicap. We estimate that such a trial should recruit about 4000 infants to have the power to detect a reduction in brain injury by one-fifth. This illustrates the formidable task of providing first-grade evidence for the clinical value of diagnostic methods. Is it a window of opportunity for the establishment of a rational basis before another technology is added to an already overly complex newborn intensive care?

Fast Doppler as a novel bedside measure of cerebral perfusion in preterm infants

“…Standard color or power Doppler ultrasonography is limited to measuring the velocities in large vessels; so, it is unable to directly assess the vascular regulation that is thought to primarily occur at the level of the capillaries and precapillary arterioles (7). Near infrared spectroscopy monitoring is a promising imaging modality that provides a continuous measure of the regional oxygenation of superficial aspects of the brain (8,9); however, it is unable to directly measure cerebral blood flow. Invasive methods of assessing cerebral perfusion, including 133 xenon clearance measurements, positron emission tomography, single-photon emission computed tomography, and arterial spin labeled perfusion magnetic resonance imaging, are able to better define true cerebral blood flow values, but their clinical value is limited due to the need for sedation and/or radiation.…”

A New Approach for Automatic Removal of Movement Artifacts in Near-Infrared Spectroscopy Time Series by Means of Acceleration Data

“…The total number of artifacts detected was much higher for AMARA (14,695) than for the human scorers (~5000-7500), ABAMAR (8478) and MARA (12,732, see Figure 3a). The mean length of the artifacts was consequently much shorter for AMARA (~7 s) than for S1 to S4 (40-100 s) and ABAMAR (24 s).…”

“…Starting at the first segment with Ck = 0 before the last trustworthy segment, the baseline of the segments with Ck = 0 are adapted to the later segments' baseline. The baseline is shifted similarly as in Equation (14). The resulting segments are saved in the vector xBW,ok,m.…”

“…650-950 nm) into tissue and measuring the diffusely back-reflected light, near-infrared spectroscopy (NIRS) is able to determine concentration changes of oxy-and deoxyhemoglobin ([O2Hb], [HHb]), which are related to changes in tissue hemodynamics and oxygenation [1][2][3][4]. For example, brain activity has been assessed using NIRS in adults [3,[5][6][7][8][9][10][11], infants and neonates [12][13][14][15], or animals [16][17][18]. During long-lasting NIRS recordings in particular, for example during sleep [19][20][21][22][23][24][25], artifacts in the NIRS data due to movements of the subjects are a common problem.…”

Сerebral oxymetry in neonatology

“…В последние годы особое внимание исследователей и клиницистов привлекает использование с этой целью у новорож-денных детей неинвазивного, безопасного и доста-точно информативного метода параинфракрасной спектроскопии (NIRS) [1,18,19,29,42,44]. Тех-нология метода основана на способности тканей пропускать свет в близком к инфракрасному диапа-зону (длина волн 700-1000 nm) и его поглощении такими хромофорами, как оксигемоглобин (Hb0 2 ), дезоксигемоглобин (HHb), цитохром С оксидаза, для каждого из которых характерен свой спектр поглощаемых волн [14,35,52].…”