Continuous, Noninvasive, and Localized Microvascular Tissue Oximetry Using Visible Light Spectroscopy

Background: The authors evaluated the ability of visible light spectroscopy (VLS) oximetry to detect hypoxemia and ischemia in human and animal subjects. Unlike near-infrared spectroscopy or pulse oximetry (SpO2), VLS tissue oximetry uses shallow-penetrating visible light to measure microvascular hemoglobin oxygen saturation (StO2) in small, thin tissue volumes. Methods: In pigs, StO2 was measured in muscle and enteric mucosa during normoxia, hypoxemia (SpO2 = 40–96%), and ischemia (occlusion, arrest). In patients, StO2 was measured in skin, muscle, and oral/enteric mucosa during normoxia, hypoxemia (SpO2 = 60–99%), and ischemia (occlusion, compression, ventricular fibrillation). Results: In pigs, normoxic StO2 was 71 ± 4% (mean ± SD), without differences between sites, and decreased during hypoxemia (muscle, 11 ± 6%; P < 0.001) and ischemia (colon, 31 ± 11%; P < 0.001). In patients, mean normoxic StO2 ranged from 68 to 77% at different sites (733 measures, 111 subjects); for each noninvasive site except skin, variance between subjects was low (e.g., colon, 69% ± 4%, 40 subjects; buccal, 77% ± 3%, 21 subjects). During hypoxemia, StO2 correlated with SpO2 (animals, r2 = 0.98; humans, r2 = 0.87). During ischemia, StO2 initially decreased at −1.3 ± 0.2%/s and decreased to zero in 3–9 min (r2 = 0.94). Ischemia was distinguished from normoxia and hypoxemia by a widened pulse/VLS saturation difference (Δ < 30% during normoxia or hypoxemia vs. Δ > 35% during ischemia). Conclusions: VLS oximetry provides a continuous, noninvasive, and localized measurement of the StO2, sensitive to hypoxemia, regional, and global ischemia. The reproducible and narrow StO2 normal range for oral/enteric mucosa supports use of this site as an accessible and reliable reference point for the VLS monitoring of systemic flow.

[1]  M F Stranc,et al.  Assessment of tissue viability using near-infrared spectroscopy. , 1998, British journal of plastic surgery.

[2]  J. Feather,et al.  A portable scanning reflectance spectrophotometer using visible wavelengths for the rapid measurement of skin pigments. , 1989, Physics in medicine and biology.

[3]  M. Dujovny,et al.  Transcranial cerebral oximetry in random normal subjects. , 1998, Neurological research.

[4]  Sergio Fantini,et al.  A haemodynamic model for the physiological interpretation of in vivo measurements of the concentration and oxygen saturation of haemoglobin. , 2002, Physics in medicine and biology.

[5]  P A Kyriacou,et al.  Investigation of the human oesophagus as a new monitoring site for blood oxygen saturation. , 2001, Physiological measurement.

[6]  A. Hanlon,et al.  Hypoxia in Human Prostate Carcinoma: An Eppendorf Po2 Study , 2001, American journal of clinical oncology.

[7]  D. Torbati,et al.  Esophageal capnometry during hemorrhagic shock and after resuscitation in rats , 2002, Critical care.

[8]  P. Marik,et al.  Sublingual capnometry versus traditional markers of tissue oxygenation in critically ill patients* , 2003, Critical care medicine.

[9]  A. Seifalian,et al.  Measurement of Hepatic Tissue Hypoxia Using Near Infrared Spectroscopy: Comparison with Hepatic Vein Oxygen Partial Pressure , 2000, European Surgical Research.

[10]  S. Nicolson,et al.  Cerebral oxygen saturation before congenital heart surgery. , 2001, The Annals of thoracic surgery.

[11]  M. Weil,et al.  Decreases in mesenteric blood flow associated with increases in sublingual PCO2 during hemorrhagic shock. , 2001, Shock.

[12]  A. Bodenham,et al.  Lack of agreement between bioimpedance and continuous thermodilution measurement of cardiac output in intensive care unit patients , 1997, Critical care.

[13]  S. Kawasaki,et al.  Use of near-infrared spectroscopic measurement at the buttocks during abdominal aortic surgery. , 2002, Circulation Journal.

[14]  M. Nakatsuka.  Assessment of Gut Mucosal Perfusion and Colonic Tissue Blood Flow During Abdominal Aortic Surgery with Gastric Tonometry and Laser Doppler Flowmetry , 2002, Vascular and endovascular surgery.

[15]  A. Grinvald,et al.  Interactions Between Electrical Activity and Cortical Microcirculation Revealed by Imaging Spectroscopy: Implications for Functional Brain Mapping , 1996, Science.

[16]  M. Imhoff,et al.  Noninvasive whole-body electrical bioimpedance cardiac output and invasive thermodilution cardiac output in high-risk surgical patients , 2000, Critical care medicine.

[17]  A. Algra,et al.  Near-infrared reflected spectroscopy and electroencephalography during carotid endarterectomy--in search of a new shunt criterion. , 1998, Neurological research.

[18]  Muscle oxygenation by fast near infrared spectrophotometry (NIRS) in ischemic forearm. , 1992, Advances in experimental medicine and biology.

[19]  P. Marik.  Sublingual capnography: a clinical validation study. , 2001, Chest.

[20]  S. Nicolson,et al.  Arterial and Venous Contributions to Near-infrared Cerebral Oximetry , 2000, Anesthesiology.

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

[22]  P. Rossini,et al.  Near Infrared Spectroscopy and Transcranial Doppler in Monohemispheric Stroke , 1999, European Neurology.

[23]  Thomas E. Moritz,et al.  Standard versus Fiberoptic Pulmonary Artery Catheterization for Cardiac Surgery in the Department of Veterans Affairs: A Prospective, Observational, Multicenter Analysis , 2002, Anesthesiology.

[24]  K. Frank,et al.  The Erlangen micro-lightguide spectrophotometer EMPHO I. , 1989, Physics in medicine and biology.

[25]  J S Beck,et al.  Spectrophotometric measurements of haemoglobin saturation and concentration in skin during the tuberculin reaction in normal human subjects. , 1992, Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics.

[26]  Fast wavelength scanning reflectance spectrophotometer for noninvasive determination of hemoglobin oxygenation in human skin. , 1994, International journal of microcirculation, clinical and experimental.

[27]  R. Mason,et al.  Intraoperative assessment of colonic perfusion using scanning laser Doppler flowmetry during colonic resection. , 2000, Journal of the American College of Surgeons.

[28]  Brian W Pogue,et al.  In vivo near-infrared spectral detection of pressure-induced changes in breast tissue. , 2003, Optics letters.

[29]  B. Chance,et al.  Near-infrared monitoring of the cerebral circulation , 1993, Journal of Clinical Monitoring.

[30]  P. Rehak,et al.  Transesophageal versus surface pulse oximetry in intensive care unit patients , 2000, Critical care medicine.

[31]  R Consunji,et al.  Increased resource use associated with catheter-related bloodstream infection in the surgical intensive care unit. , 2001, Archives of surgery.

[32]  David A. Benaron,et al.  Quantitative clinical nonpulsatile and localized visible light oximeter: design of the T-Stat tissue oximeter , 2003, SPIE BiOS.

[33]  A. du Plessis,et al.  Utility of near-infrared spectroscopic measurements during deep hypothermic circulatory arrest. , 2000, The Annals of thoracic surgery.

[34]  P. Fortune,et al.  Cerebro-splanchnic oxygenation ratio (CSOR) using near infrared spectroscopy may be able to predict splanchnic ischaemia in neonates , 2001, Intensive Care Medicine.

[35]  T. Mogensen,et al.  Muscle oxygen saturation during surgery in the lithotomy position. , 1997, Clinical physiology.

[36]  P. Rolfe,et al.  A Comparison of Pulse Oximetry and Near Infrared Spectroscopy (NIRS) in the Detection of Hypoxaemia Occurring With Pauses in Nasal Airflow in Neonates , 1999, Journal of Clinical Monitoring and Computing.