Tissue oxygenation measured with near-infrared spectroscopy during normobaric and hyperbaric oxygen breathing in healthy subjects.
To evaluate the possibility of using near-infrared spectroscopy (NIRS) to measure tissue oxygenation (StO(2)) during hyperbaric oxygen (HBO) therapy. Nine healthy volunteers (1 female) age 25-37 years, breathed air or oxygen. Tissue oxygenation was measured using NIRS on the thumb. Subjects were blinded to breathing gas. A range of partial pressures of oxygen were administered in 10-min intervals: 21, 101, 21 kPa (compression to 280 kPa), 59, 280, 59 (decompression), 21 kPa. Data were averaged over last 5 min at each pressure. When switching from air to normobaric oxygen (NBO 101 kPa) StO(2) increased from 83% (82-85%, median and interquartile range) to 85% (84-87%) (P < 0.01), while when switching from air at pressure (59 kPa O(2)) to HBO (280 kPa), StO(2) increased from 85% (85-86%) to 88% (87-89%) (P < 0.001). There was no difference between baseline StO(2) while air breathing before NBO or after decompression. Values did not reach the maximal value of 100% at any point. The changes in hemoglobin oxygen saturation in tissue registered by the NIRS monitor when switching from air to oxygen followed inspired PO(2) under normobaric and hyperbaric conditions.
Larsson
Agneta
A
Department of Physiology and Pharmacology, Section for Anaesthesiology and Intensive Care Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden. agneta.c.larsson@karolinska.se
Uusijärvi
Johan
J
Eksborg
Staffan
S
Lindholm
Peter
P
D000280:Administration, Inhalation; D000328:Adult; D001794:Blood Pressure; D005260:Female; D006339:Heart Rate; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D006931:Hyperbaric Oxygenation; D008297:Male; D010100:Oxygen / Q000008:administration & dosage / Q000378:metabolism*; D010101:Oxygen Consumption; D010313:Partial Pressure; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation; D013933:Thumb; D013997:Time Factors
D006454:Hemoglobins; D010100:Oxygen