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Cerebral Oximetry Monitoring with Near Infrared Spectroscopy Detects Alterations in Oxygenation Before Pulse Oximetry

2008; SAGE Publishing; Volume: 23; Issue: 6 Linguagem: Inglês

10.1177/0885066608324380

1525-1489

Joseph D. Tobias,

Non-Invasive Vital Sign Monitoring

Background: The monitoring of oxygenation may be imperative to ensure patient safety and optimal outcome. We anecdotally noted that monitoring cerebral oxygenation (rSO 2 ) using near infrared spectroscopy may provide an earlier warning of changes in oxygenation than pulse oximetry. Methods: Patients scheduled for airway laser surgery requiring intermittent periods of apnea were monitored with both a cerebral oximeter and a pulse oximeter. Following inhalational induction and endotracheal intubation, anesthesia was maintained with propofol. After 3 minutes of ventilation with 100% oxygen, the endotracheal tube was removed and laser surgery performed on the airway during apnea. The time for a 5% and a 10% decrease in the cerebral oximeter and the pulse oximeter was noted. Results: The study cohort included 10 infants and children ranging in age from 1 month to 7 years. The time for a 5% decrease of the rSO 2 was 94 + 8 seconds versus 146 + 49 seconds for a 5% decrease of the SaO 2 (P < .0001). During all 42 episodes of apnea, the rSO 2 decreased by 5% before the SaO 2 had decreased by 5%. When the SaO 2 had decreased by 5% (down to 95% from the starting value of 100%), the rSO 2 had decreased by 16 + 4%. The time for a 10% decrease of the rSO 2 was 138 + 29 seconds versus 189 + 64 seconds for a 10% decrease of the SaO 2 (P = .0009). In all 42 cases, the rSO 2 decreased by 10% before the SaO 2 . Conclusions: Cerebral oxygenation monitoring using near infrared spectroscopy detects changes in oxygenation earlier than standard pulse oximetry.