AUTHOR=Massa-Buck Beri , Amendola Virginia , McCloskey Reagan , Rais-Bahrami Khodayar 

TITLE=Significant Correlation between Regional Tissue Oxygen Saturation and Vital Signs of Critically Ill Infants

JOURNAL=Frontiers in Pediatrics

VOLUME=5

YEAR=2017

URL=https://www.frontiersin.org/journals/pediatrics/articles/10.3389/fped.2017.00276

DOI=10.3389/fped.2017.00276

ISSN=2296-2360

ABSTRACT=<sec id="ST1"><title>Background</title><p>Near-infrared spectroscopy (NIRS) has been used to non-invasively measure specific tissue oxygen saturation (StO<sub>2</sub>) continuously. Cerebral autoregulation status can be derived from NIRS and arterial blood pressure. The relationship of both cerebral and somatic StO<sub>2</sub>, fractional tissue oxygen extraction (FTOE), and cerebro-splanchnic oxygenation ratio (CSOR) with measured vital sign parameters for Neonatal Intensive Care Unit (NICU) patients has not been well studied.</p></sec><sec id="ST2"><title>Objective</title><p>The aims of this study are to determine if significant relationships of brain and somatic StO<sub>2</sub>, brain and somatic FTOE, and CSOR parameters with vital signs for neonates exist and assess relationship between pressure passivity index, cerebral autoregulation, and mean blood pressure (MBP).</p></sec><sec id="ST3"><title>Design/methods</title><p>Neonates weighing &lt; 5 kg, preferentially with an arterial catheter, were enrolled in the study. FORE-SIGHT Elite (CASMedical Systems, Inc., Branford, CT, USA) cerebral and somatic NIRS sensors were placed over the abdominal right upper quadrant and right frontal-temporal area of the forehead for 24 h. Vital signs including arterial MBP were recorded simultaneously from the patients’ bedside monitor. Data were averaged into 60 s windows and analyzed using linear regression. Results were stratified by gestational age (GA), birth weight (BW), and presence of brain abnormality.</p></sec><sec id="ST4"><title>Results</title><p>Data were obtained from 27 subjects (GA 22.2–42 weeks). Two subjects did not have an arterial line, thus they were not included in the MBP measurements. There were ~28,000–31,000 paired data points per comparison. Significant positive and negative correlations (<italic>p</italic> value &lt; 0.0001) were noted between NIRS parameters and vital signs. When stratified by BW, there was a positive correlation between brain StO<sub>2</sub> (StO<sub>2</sub>B) and MBP in the &lt;1,500 g BW group (<italic>r</italic> = 0.193) and a negative correlation in &gt;1,500 g group (<italic>r</italic> = 0.057). Brain and somatic FTOE in &lt;1,500 g BW revealed a negative correlation with MBP (<italic>r</italic> = 0.172 and <italic>r</italic> = 0.086, respectively). In patients with an abnormal brain scan, a positive correlation was noted between StO<sub>2</sub>B and MBP (<italic>r</italic> = 0.354), and a negative correlation was noted between FTOE-B and MBP (<italic>r</italic> = 0.305). Generated pressure passive index plots suggested good cerebral autoregulation at low normal MBP ranges for lower weight and GA subjects.</p></sec><sec id="ST5"><title>Conclusion</title><p>There is a significant correlation between cerebral and somatic StO<sub>2</sub> and FTOE with measured vital sign parameters in NICU patients.</p></sec>