Near Infra-red Spectroscopy for Detection of Intracranial Haematoma

Non-invasive Neuro-monitoring for Head Injury: Use of Near Infra-red Spectroscopy for Early Detection of Delayed Intracranial Haematoma

Fall with head injury is becoming an epidemic challenge especially with the ageing population. Contributing factors for mortality and poor functional outcome included development of cerebral contusion and delayed traumatic intracerebral haematoma. There is a higher prevalence especially with the increasing use of antiplatelets and anticoagulants.

Non-invasive monitoring such as near-infrared spectroscopy (NIRS) is sensitive in detecting intracranial changes. The role and efficacy of this non-invasive method has not been specifically established in patients with head injury as an initial non-operative monitoring. This is particular important in the setting of a general ward in which nursing staff is limited. The advantages of these noninvasive monitoring might have a role of continuous neuro-monitoring. They can also potentially reduce the number of unnecessary repeated CT Brain in the context of limited radiology staff and resources. Timely detection and treatment of this condition accordingly is crucial. Potential options of non-invasive monitoring such as nearinfrared spectroscopy (NIRS) is to be investigated.

The aim of this study is to determine the sensitivity and specificity of NIRS as a non-invasive monitoring in detecting delayed intracranial injuries in comparison with the Gold Standard CT Brain. Study design is Prospective sensitivity and specificity study of Near Infra-red Spectroscopy (NIRS) as a non-invasive monitoring in detecting delayed intracranial injuries in comparison with the Gold Standard CT Brain in Hong Kong Chinese. Consecutive patients admitted to Prince of Wales Hospital, Hong Kong would be recruited. Outcome measures including correlation of non-invasive monitoring with near-infrared spectroscopy (NIRS) to CT Brain findings including any increase in haematoma size, cerebral edema or mass effect. Secondary outcome including 30 days mortality and functional outcome at 3 months.

Introduction: Fall with head injury is becoming an epidemic challenge especially with the ageing population. Contributing factors for mortality and poor functional outcome included development of cerebral contusion and delayed traumatic intracerebral haematoma. There is a higher prevalence especially with the increasing use of antiplatelets and anticoagulants.

Non-invasive monitoring such as near-infrared spectroscopy (NIRS) is sensitive in detecting intracranial changes. The role and efficacy of this non-invasive method has not been specifically established in patients with head injury as an initial non-operative monitoring. This is particular important in the setting of a general ward in which nursing staff is limited. The advantages of these non-invasive monitoring might have a role of continuous neuro-monitoring. They can also potentially reduce the number of unnecessary repeated CT Brain in the context of limited radiology staff and resources.

Timely detection and treatment of this condition accordingly is crucial. Potential options of non-invasive monitoring such as near-infrared spectroscopy (NIRS) is to be investigated.

Aims and Hypotheses to be tested:

The aim of this study is to determine the sensitivity and specificity of near-infrared spectroscopy (NIRS) as a non-invasive monitoring in detecting delayed intracranial injuries in comparison with the Gold Standard CT Brain.

Plan of Investigation:

This is a prospective sensitivity and specificity correlation study of Near Infra-red Spectroscopy (NIRS) as a non-invasive monitoring in detecting delayed intracranial injuries in comparison with the Gold Standard CT Brain in Hong Kong Chinese. Consecutive patients admitted to Prince of Wales Hospital, Hong Kong would be recruited.

Consecutive patients fulfilling the inclusion and exclusion criteria are treated with standard of care with near-infrared spectroscopy (NIRS). Criteria to proceed for repeat CT Brain scan 1) clinical deterioration of GCS >2 points, 2) NIRS monitoring has increase in difference in absorbance of light at 760nm >0.3, or 3) 8 hours after admission for baseline interval scan for all patients as part of the standard of care. Non-invasive monitoring with near-infrared spectroscopy (NIRS) would be applied to all patients' forehead for consecutively 48 hours after admission.

Inclusion criteria

1. Age greater than or equal to 18 years old,
2. History of traumatic brain injury,
3. Radiological evidence of intracranial haematoma,
4. Glasgow Coma Scale (GCS) less than 15 upon admission,
5. Not undergoing immediate operation,
6. Admission to the general ward or high dependence unit of Neurosurgery, Prince of Wales Hospital.

Exclusion criteria

1. Presence of frontal scalp laceration preventing the application of non-invasive monitoring on the forehead,
2. Presence of pneumocephale,
3. Requirement of immediate surgical intervention as judged by the on-call neurosurgeon.
4. Patients who have joined other drug trial in the last four weeks;
5. Pregnant or on breast feeding;
6. Any other reasons that the researchers consider unsuitable.

Primary outcome - Correlation coefficient of near-infrared spectroscopy (NIRS) to CT Brain findings including any increase in haematoma size, cerebral edema or mass effect.

Secondary outcomes

- Secondary outcome including number of CT scan performed, correlation of NIRS reading with Glasgow coma scale (GCS), rate of intervention with either medical treatment such as use of mannitol, Transamin or blood product transfusion, or surgical treatment such as operation, 30 days mortality and functional outcome at 3 months.

Purpose and Potential:

Near-infrared spectroscopy (NIRS) can offer continuous neuro-monitoring. This is particular important in the setting of a general ward in which nursing staff is limited. This allows early detection of delayed haematoma for early intervention. At the same time, the use of NIRS can potentially reduce the number of unnecessary repeated CT Brain in the context of limited radiology staff and resources.

Inclusion Criteria:

1. Age greater than or equal to 18 years old,
2. History of traumatic brain injury,
3. Radiological evidence of intracranial haematoma,
4. Glasgow Coma Scale (GCS) less than 15 upon admission,
5. Not undergoing immediate operation,
6. Admission to the general ward or high dependence unit of Neurosurgery, Prince of Wales Hospital.

Exclusion Criteria:

1. Presence of frontal scalp laceration preventing the application of non-invasive monitoring on the forehead,
2. Presence of pneumocephale,
3. Requirement of immediate surgical intervention as judged by the on-call neurosurgeon.
4. Patients who have joined other drug trial in the last four weeks;
5. Pregnant or on breast feeding;
6. Any other reasons that the researchers consider unsuitable.