Detecting low brain oxygen levels in patients undergoing non-cardiac surgery to assess its association with post-operative delirium

Using near-infrared spectroscopy to detect cerebral desaturation in non-cardiac surgery and assess its relationship with post-operative delirium– a pilot study

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

ISRCTN

Registry ID

ISRCTN15439489

Enrollment

Registered

2018-11-06

Start date

2018-09-03

Completion date

Unknown

Last updated

2021-04-12

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Postoperative delirium Mental and Behavioural Disorders Postoperative delirium

Interventions

Measurement of cerebral oximetry, from entering the anaesthetic room to 1 hour after the end of surgery

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Patients: 1. Age = 60 2. Able to provide informed consent Surgical types: 1. Scheduled orthopaedic surgery (GA/sedation +/- regional) 2. Scheduled gastrointestinal surgery (open/closed) 3. Scheduled robotic urological or gynaecological surgery 4. Emergency laparotomy surgery

Exclusion criteria

Exclusion criteria: 1. Acute or chronic cognitive impairment, including delirium or dementia 2. Previous neurosurgery 3. Insufficient English language to discuss participation

Design outcomes

Primary

Measure	Time frame
The following will be assessed once the final participant has finished the study (as these measurements require the total number of patients): 1. Proportion of patients enrolled in whom we acquired interpretable regional oxygen saturation (rScO2) data (%) is assessed: 100 X total number recruited with interpretable data / total number recruited 2. Proportion of patients enrolled in whom we acquired delirium data (%) is assessed: 100 X total number recruited with delirium data / total number recruited	—

Measure

Time frame

The following will be assessed once the final participant has finished the study (as these measurements require the total number of patients): 1. Proportion of patients enrolled in whom we acquired interpretable regional oxygen saturation (rScO2) data (%) is assessed: 100 X total number recruited with interpretable data / total number recruited 2. Proportion of patients enrolled in whom we acquired delirium data (%) is assessed: 100 X total number recruited with delirium data / total number recruited

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Secondary

Measure	Time frame
For each cohort of surgical patients, and the cohort as a whole, use descriptive statistics (proportion (%), or mean and standard deviation, or median and interquartile range – according to parametric or non-parametric distribution respectively): 1. Incidence of cerebral desaturation using three previously utilised definitions (as below). Cerebral saturation is assessed using a cerebral oximetry machine, recorded continuously during surgery and for 1 hour after surgery. 1.1. Any occurrence of a decrease of 10% from baseline 1.2. Any occurrence of a decrease of 20% from baseline 1.3. Any occurrence of an absolute value of regional oxygen saturation (rScO2) <50% 2. Average duration of relative desaturation - time with rScO2 = 60% 3. Incidence of systemic hypotension using three common definitions (as below). Systolic hypotension is assessed using blood pressure readings taken during surgery. Baseline values will be obtained from the pre-operative clinic; however, if this is not possible then the pre-induction blood pressure will be used as a baseline. 3.1. Any occurrence of systolic blood pressure (BP) =20% of baseline 3.2. Any occurrence of systolic BP =30% of baseline 3.3. Any occurrence of systolic BP =40% of baseline 4. Average duration of systemic hypotension - time with mean arterial pressure (MAP) =20% of baseline 5. Incidence of hypoxaemia using three definitions (as below). Hypoxaemia will be assessed using saturation probe readings during surgery. 5.1. Any occurrence of blood oxygen saturation (SpO2) = 88% 5.2. Any occurrence of SpO2 = 90% 5.3. Any occurrence of SpO2 = 92% 6. Average duration of hypoxaemia - time with SpO2 = 90% 7. Utilisation of vasopressor drugs (a-agonists) - we will record either a vaso	—

Measure

Time frame

For each cohort of surgical patients, and the cohort as a whole, use descriptive statistics (proportion (%), or mean and standard deviation, or median and interquartile range – according to parametric or non-parametric distribution respectively): 1. Incidence of cerebral desaturation using three previously utilised definitions (as below). Cerebral saturation is assessed using a cerebral oximetry machine, recorded continuously during surgery and for 1 hour after surgery. 1.1. Any occurrence of a decrease of 10% from baseline 1.2. Any occurrence of a decrease of 20% from baseline 1.3. Any occurrence of an absolute value of regional oxygen saturation (rScO2) <50% 2. Average duration of relative desaturation - time with rScO2 = 60% 3. Incidence of systemic hypotension using three common definitions (as below). Systolic hypotension is assessed using blood pressure readings taken during surgery. Baseline values will be obtained from the pre-operative clinic; however, if this is not possible then the pre-induction blood pressure will be used as a baseline. 3.1. Any occurrence of systolic blood pressure (BP) =20% of baseline 3.2. Any occurrence of systolic BP =30% of baseline 3.3. Any occurrence of systolic BP =40% of baseline 4. Average duration of systemic hypotension - time with mean arterial pressure (MAP) =20% of baseline 5. Incidence of hypoxaemia using three definitions (as below). Hypoxaemia will be assessed using saturation probe readings during surgery. 5.1. Any occurrence of blood oxygen saturation (SpO2) = 88% 5.2. Any occurrence of SpO2 = 90% 5.3. Any occurrence of SpO2 = 92% 6. Average duration of hypoxaemia - time with SpO2 = 90% 7. Utilisation of vasopressor drugs (a-agonists) - we will record either a vaso

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Countries

United Kingdom

Contacts

Public ContactBen Creagh-Brown

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 4, 2026