Quantifying cerebral hypoxia by near-infrared spectroscopy tissue oximetry: the role of arterial-to-venous blood volume ratio

Abstract. Tissue oxygenation estimated by near-infrared spectroscopy (NIRS) is a volume-weighted mean of the arterial and venous hemoglobin oxygenation. In vivo validation assumes a fixed arterial-to-venous volume-ratio (AV-ratio). Regulatory cerebro-vascular mechanisms may change the AV-ratio. We used hypotension to investigate the influence of blood volume distribution on cerebral NIRS in a newborn piglet model. Hypotension was induced gradually by inflating a balloon-catheter in the inferior vena cava and the regional tissue oxygenation from NIRS (rStO2,NIRS) was then compared to a reference (rStO2,COX) calculated from superior sagittal sinus and aortic blood sample co-oximetry with a fixed AV-ratio. Apparent changes in the AV-ratio and cerebral blood volume (CBV) were also calculated. The mean arterial blood pressure (MABP) range was 14 to 82 mmHg. PaCO2 and SaO2 were stable during measurements. rStO2,NIRS mirrored only 25% (95% Cl: 21% to 28%, p<0.001) of changes in rStO2,COX. Calculated AV-ratio increased with decreasing MABP (slope: −0.007·mmHg−1, p<0.001). NIRS estimates that CBV decreased with decreasing MABP (slope: 0.008  ml/100  g/mmHg, p<0.001). Thus, cerebral NIRS oximetry responded poorly to changes in tissue oxygenation during hypotension induced by decreased preload. An increase in the AV-ratio during hypotension due to arterial vasodilation and, possibly, cerebral venous collapse may be a part of the explanation.

[1]  Simon Hyttel-Sorensen,et al.  Peripheral tissue oximetry: comparing three commercial near-infrared spectroscopy oximeters on the forearm , 2013, Journal of Clinical Monitoring and Computing.

[2]  D. Prough,et al.  Validation in Volunteers of a Near-Infrared Spectroscope for Monitoring Brain Oxygenation In Vivo , 1996, Anesthesia and analgesia.

[3]  S R Nelson,et al.  Use of specific gravity in the measurement of cerebral edema. , 1971, Journal of applied physiology.

[4]  P. Rolfe,et al.  Plethysmographic validation of near infrared spectroscopic monitoring of cerebral blood volume. , 1992, Archives of disease in childhood.

[5]  Caroline A Rickards,et al.  Coupling between arterial pressure, cerebral blood velocity, and cerebral tissue oxygenation with spontaneous and forced oscillations , 2015, Physiological measurement.

[6]  B. Schaller,et al.  Physiology of cerebral venous blood flow: from experimental data in animals to normal function in humans , 2004, Brain Research Reviews.

[7]  G. Greisen,et al.  Near-infrared monitoring of cerebral tissue oxygen saturation and blood volume in newborn piglets. , 1997, The American journal of physiology.

[8]  B. Bhat,et al.  Management of Shock in Neonates , 2015, The Indian Journal of Pediatrics.

[9]  Martin Wolf,et al.  Calibration of a prototype NIRS oximeter against two commercial devices on a blood-lipid phantom. , 2013, Biomedical optics express.

[10]  Marek Czosnyka,et al.  Noninvasive Autoregulation Monitoring with and without Intracranial Pressure in the Naïve Piglet Brain , 2010, Anesthesia and analgesia.

[11]  N. Labropoulos,et al.  Cerebral oximetry and stump pressure as indicators for shunting during carotid endarterectomy: comparative evaluation , 2011, Vascular.

[12]  Gerhard Pichler,et al.  Regional tissue oxygen saturation: comparability and reproducibility of different devices. , 2011, Journal of biomedical optics.

[13]  Istvan Seri,et al.  Neonatal blood pressure support: the use of inotropes, lusitropes, and other vasopressor agents. , 2012, Clinics in perinatology.

[14]  Seong-Gi Kim,et al.  Relative changes of cerebral arterial and venous blood volumes during increased cerebral blood flow: Implications for BOLD fMRI , 2001, Magnetic resonance in medicine.

[15]  Weili Lin,et al.  Cerebral venous and arterial blood volumes can be estimated separately in humans using magnetic resonance imaging , 2002, Magnetic resonance in medicine.

[16]  J. Leblanc,et al.  Comparison of Two Spatially Resolved NIRS Oxygenation Indices , 2002, Journal of Clinical Monitoring and Computing.

[17]  Simon Hyttel-Sorensen,et al.  Tissue oximetry: a comparison of mean values of regional tissue saturation, reproducibility and dynamic range of four NIRS-instruments on the human forearm , 2011, Biomedical optics express.

[18]  K. Barrington,et al.  Hypotension and shock in the preterm infant. , 2008, Seminars in fetal & neonatal medicine.

[19]  J Marshall,et al.  In vivo Measurement of Regional Cerebral Haematocrit Using Positron Emission Tomography , 1984, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[20]  Martin Wolf,et al.  Cerebral near infrared spectroscopy oximetry in extremely preterm infants: phase II randomised clinical trial , 2015, BMJ : British Medical Journal.

[21]  Marek Czosnyka,et al.  Cerebrovascular reactivity measured by near-infrared spectroscopy. , 2009, Stroke.

[22]  I. Seri,et al.  Evidence-based versus pathophysiology-based approach to diagnosis and treatment of neonatal cardiovascular compromise. , 2015, Seminars in fetal & neonatal medicine.

[23]  Nadine Brew,et al.  Cerebral vascular regulation and brain injury in preterm infants. , 2014, American journal of physiology. Regulatory, integrative and comparative physiology.

[24]  Adelina Pellicer,et al.  Near-infrared spectroscopy: a methodology-focused review. , 2011, Seminars in fetal & neonatal medicine.

[25]  M Wolf,et al.  Comparison of tissue oximeters on a liquid phantom with adjustable optical properties. , 2016, Biomedical optics express.

[26]  V. Brodecky,et al.  Cerebral Arterial and Venous Contributions to Tissue Oxygenation Index Measured Using Spatially Resolved Spectroscopy in Newborn Lambs , 2010, Anesthesiology.

[27]  I. Seri,et al.  Systemic and cerebral hemodynamics during the transitional period after premature birth. , 2009, Clinics in perinatology.

[28]  I. Seri,et al.  Management of hypotension and low systemic blood flow in the very low birth weight neonate during the first postnatal week , 2006, Journal of Perinatology.

[29]  Yukio Kobayashi,et al.  Tissue oxygenation monitor using NIR spatially resolved spectroscopy , 1999, Photonics West - Biomedical Optics.

[30]  D. Ward,et al.  Accuracy of a Cerebral Oximeter in Healthy Volunteers under Conditions of Isocapnic Hypoxia , 1998, Anesthesiology.

[31]  C. Elwell,et al.  Cerebral Blood Flow Is Independent of Mean Arterial Blood Pressure in Preterm Infants Undergoing Intensive Care , 1998, Pediatrics.

[32]  E. Dempsey,et al.  Treating hypotension in the preterm infant: when and with what: a critical and systematic review , 2007, Journal of Perinatology.

[33]  D. Delpy,et al.  Optical pathlength measurements on adult head, calf and forearm and the head of the newborn infant using phase resolved optical spectroscopy. , 1995, Physics in medicine and biology.

[34]  G. Greisen Autoregulation of cerebral blood flow in newborn babies. , 2005, Early human development.

[35]  Gorm Greisen,et al.  Cerebral oxygenation after birth – a comparison of INVOS® and FORE‐SIGHT™ near‐infrared spectroscopy oximeters , 2014, Acta paediatrica.

[36]  C. Rickards,et al.  The role of cerebral oxygenation and regional cerebral blood flow on tolerance to central hypovolemia. , 2016, American journal of physiology. Regulatory, integrative and comparative physiology.

[37]  G. Pichler,et al.  Borderline hypotension: how does it influence cerebral regional tissue oxygenation in preterm infants? , 2015, The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians.