Cerebral oxygenation monitoring using near infrared spectroscopy during controlled hypotension

Objectives The aim of our study was to evaluate the near-infrared spectroscopy monitoring system to detect cerebral ischaemia, find indications for selective shunting during carotid endarterectomy and compare it with an internal carotid artery stump pressure monitoring technique in patients operated under local anaesthesia. Methods During January 2015 and November 2018, 131 patients undergoing carotid endarterectomy under local anaesthesia were prospectively included in the study. Near-infrared spectroscopy as intraoperative monitoring was applied and compared with stump pressure. Results Carotid endarterectomy was performed successfully in 106 patients operated under local anaesthesia. Meanwhile, 25 patients developed neurological changes (motor or consciousness impairment, weakness of extremities, cognitive decline) during clamping, and all of them received a shunt. ΔrSO2, stump pressure and rSO2 (–11 ± 8%, 31 ± 6mmHg, 58 ± 11) values were smaller in the group of shunted subjects versus non-shunted group subjects (–2 ± 5%, 61 ± 17 mmHg, 64 ± 8) after 1 min of internal carotid artery clamping ( p < 0.05). Statistical analysis showed a sensitivity of 90% (95% CI: 0.85–0.95) and a specificity of 70% (95% CI: 0.62–0.78) for a ≥10% drop in ΔrSO2 to predict ischaemia symptoms during carotid clamping. Using stump pressure with a cut-off value of ≤40 mmHg for predicting symptoms, the sensitivity was 82% and specificity 54%. Conclusions Near-infrared spectroscopy is a suitable non-invasive cerebral oxygenation monitoring method during carotid endarterectomy. A 10% decrease of ΔrSO2 had a good correlation with clinical cerebral ischaemia signs and matched well with the stump pressure cut-off value of ≤40 mmHg. There is a possibility of near-infrared spectroscopy to replace stump pressure in cerebral oxygenation monitoring during carotid endarterectomy. However, we need larger prospective multicentre studies to identify the optimal threshold for shunt requirement.

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The utility of cerebral oxygenation monitoring in premature neonates

Journal of Medical Science ◽

10.20883/medical.e485 ◽

2020 ◽

Vol 89 (4) ◽

pp. e485

Author(s):

Saudamini Nesargi ◽

Alexander Nitsch ◽

Martin Wolf

Keyword(s):

Infrared Spectroscopy ◽

Preterm Infants ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Cerebral Oxygenation ◽

Ductus Arteriosus ◽

Neurological Outcomes ◽

Standard Set ◽

Oxygenation Monitoring ◽

The Brain

Near-infrared spectroscopy allows the measurement of cerebral oxygenation in preterm infants. This study aimed to demonstrate several highly relevant clinical situations in preterm infants in which the standard set of monitoring parameters without near-infrared spectroscopy is not sufficient to detect possible adverse situations, possibly resulting in severe complications, i.e. adverse neurological outcomes. The examples include situations of low blood pressure, persistent open ductus arteriosus, malfunctioning autoregulation of the brain oxygenation, and periods of irregular breathing. Without near-infrared spectroscopy, it is impossible to determine whether such a situation imposes any risk for the brain, whereas the measurement of cerebral oxygenation as an additional source of information enables the clinician to recognise these conditions and modify treatment or use countermeasures to protect the patient from brain damage and ensuing lifelong disabilities.

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