Incidence of Intracranial Hypertension During Liver Transplantation Estimated by Non-invasive Ultrasound Methods.

Study Overview
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Brief Summary
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Acute or chronic liver failure (fulminant hepatitis or advanced cirrhosis) disrupts brain physiology. Beyond classical hepatic encephalopathy, intracranial hypertension may occur.During liver transplantation (LT) surgery, many factors can lead to cerebral assault. In addition, intracranial hypertension measured with invasive methods has been described in certain phases of LT, especially at the time of reperfusion. The invasive monitoring of the intracranial pressure is not used in these patients, due to a high risk of infection and bleeding. The non-invasive monitoring of intracranial pressure has been widely developed in recent years : transcranial doppler and recently ultrasound of the optic nerve sheath (ONSD) allow an effective detection of intracranial hypertension.

Official Title
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Incidence of Intracranial Hypertension During Liver Transplantation Estimated by Non-invasive Ultrasound Methods.

Conditions
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Liver Transplantation

Intervention / Treatment
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* Device: Ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients ≥ 18 years Patients who underwent orthotopic liver transplantation Patients who have received clear information and not opposed to participate in the study Patients affiliated to a social security scheme or similar Patients not undergoing a measure of legal protection Exclusion Criteria: Opposition to participation in the study Patients < 18 years Pregnant women or breastfeeding Deprived of individual liberty Non-affiliated to a social security scheme Known ophthalmic pathology: untreated cataracts, glaucoma

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Patients undergoing liver transplantation<br> | Device: Ultrasound<br>* Ultrasound measurements of the optic nerve sheath diameter and intracranial Doppler, at 4 time points during surgery (incision, anhepatic phase + 30 min, declamping + 5 min, declamping + 30 min), and at day 1 and day 5 after surgery, to detect presence of intracranial hypertension. Search of any neurological complication during the 5 postoperative days.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Measure of the optic nerve sheath diameter during surgery. | A value of the optic nerve sheath diameter (averaged over 2 measures) greater than 5.7 mm will be considered pathological, indicating the strong likelihood of intracranial hypertension (PPV near 100% for an intracranial pressure > 25 cmh2o in the literature) The optic nerve sheath diameter will be measured by ultrasonography, in accordance with existing protocols: Use probe 7.5 Mhz in 2D mode, patient supine dorsi, implementation of ultrasound gel on the closed eyelid, search for the optimal window 3mm, optic nerve sheath diameter measurement behind the retina using an electronic cursor along an axis perpendicular to the optic nerve. 2 measurements per side (sagittal and transverse plane) averaged. Values> 5.7mm are deemed pathological. | at incision | 
| Measure of the optic nerve sheath diameter during surgery. | A value of the optic nerve sheath diameter (averaged over 2 measures) greater than 5.7 mm will be considered pathological, indicating the strong likelihood of intracranial hypertension (PPV near 100% for an intracranial pressure > 25 cmh2o in the literature) The optic nerve sheath diameter will be measured by ultrasonography, in accordance with existing protocols: Use probe 7.5 Mhz in 2D mode, patient supine dorsi, implementation of ultrasound gel on the closed eyelid, search for the optimal window 3mm, optic nerve sheath diameter measurement behind the retina using an electronic cursor along an axis perpendicular to the optic nerve. 2 measurements per side (sagittal and transverse plane) averaged. Values> 5.7mm are deemed pathological. | at anhepatic phase + 30 min | 
| Measure of the optic nerve sheath diameter during surgery. | A value of the optic nerve sheath diameter (averaged over 2 measures) greater than 5.7 mm will be considered pathological, indicating the strong likelihood of intracranial hypertension (PPV near 100% for an intracranial pressure > 25 cmh2o in the literature) The optic nerve sheath diameter will be measured by ultrasonography, in accordance with existing protocols: Use probe 7.5 Mhz in 2D mode, patient supine dorsi, implementation of ultrasound gel on the closed eyelid, search for the optimal window 3mm, optic nerve sheath diameter measurement behind the retina using an electronic cursor along an axis perpendicular to the optic nerve. 2 measurements per side (sagittal and transverse plane) averaged. Values> 5.7mm are deemed pathological. | at declamping + 5 min | 
| Measure of the optic nerve sheath diameter during surgery. | A value of the optic nerve sheath diameter (averaged over 2 measures) greater than 5.7 mm will be considered pathological, indicating the strong likelihood of intracranial hypertension (PPV near 100% for an intracranial pressure > 25 cmh2o in the literature) The optic nerve sheath diameter will be measured by ultrasonography, in accordance with existing protocols: Use probe 7.5 Mhz in 2D mode, patient supine dorsi, implementation of ultrasound gel on the closed eyelid, search for the optimal window 3mm, optic nerve sheath diameter measurement behind the retina using an electronic cursor along an axis perpendicular to the optic nerve. 2 measurements per side (sagittal and transverse plane) averaged. Values> 5.7mm are deemed pathological. | at declamping + 30 min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Measurement of intracranial hypertension with transcranial Doppler during surgery. | Diastolic velocity value of less than 20 cm s-1 and a pulsatility index greater than 1.4 will be considered pathological, indicating a high probability of intracranial hypertension. The transcranial Doppler measurements are performed according to the existing protocols: use of a cardiac probe 2 Mhz, positioned temporal window, the circle of Willis color Doppler tracking then collecting the Doppler signal of the middle cerebral artery in Doppler pulsed with the insonation angle as small as possible to a depth between 40 and 60 mm. Measuring systolic, diastolic and mean velocity )Vs, Vd, Vm) and calculating the pulsatility Index (PI) bilaterally. PI values of> 1.4 and Vd <20 cm s-1 will be considered pathological. | at incision | 
| Measurement of intracranial hypertension with transcranial Doppler during surgery. | Diastolic velocity value of less than 20 cm s-1 and a pulsatility index greater than 1.4 will be considered pathological, indicating a high probability of intracranial hypertension. The transcranial Doppler measurements are performed according to the existing protocols: use of a cardiac probe 2 Mhz, positioned temporal window, the circle of Willis color Doppler tracking then collecting the Doppler signal of the middle cerebral artery in Doppler pulsed with the insonation angle as small as possible to a depth between 40 and 60 mm. Measuring systolic, diastolic and mean velocity )Vs, Vd, Vm) and calculating the pulsatility Index (PI) bilaterally. PI values of> 1.4 and Vd <20 cm s-1 will be considered pathological. | at anhepatic phase + 30 min | 
| Measurement of intracranial hypertension with transcranial Doppler during surgery. | Diastolic velocity value of less than 20 cm s-1 and a pulsatility index greater than 1.4 will be considered pathological, indicating a high probability of intracranial hypertension. The transcranial Doppler measurements are performed according to the existing protocols: use of a cardiac probe 2 Mhz, positioned temporal window, the circle of Willis color Doppler tracking then collecting the Doppler signal of the middle cerebral artery in Doppler pulsed with the insonation angle as small as possible to a depth between 40 and 60 mm. Measuring systolic, diastolic and mean velocity )Vs, Vd, Vm) and calculating the pulsatility Index (PI) bilaterally. PI values of> 1.4 and Vd <20 cm s-1 will be considered pathological. | at declamping + 5 min | 
| Measurement of intracranial hypertension with transcranial Doppler during surgery. | Diastolic velocity value of less than 20 cm s-1 and a pulsatility index greater than 1.4 will be considered pathological, indicating a high probability of intracranial hypertension. The transcranial Doppler measurements are performed according to the existing protocols: use of a cardiac probe 2 Mhz, positioned temporal window, the circle of Willis color Doppler tracking then collecting the Doppler signal of the middle cerebral artery in Doppler pulsed with the insonation angle as small as possible to a depth between 40 and 60 mm. Measuring systolic, diastolic and mean velocity )Vs, Vd, Vm) and calculating the pulsatility Index (PI) bilaterally. PI values of> 1.4 and Vd <20 cm s-1 will be considered pathological. | at declamping + 30 min | 
| Measurement of intracranial hypertension with transcranial Doppler | we use the same methods and the same thresholds as those used during surgery (primary outcome measure, and measure1 of secondary outcome measure) | at 1 day after surgery. | 
| Measure of the optic nerve sheath diameter after surgery. | we use the same methods and the same thresholds as those used during surgery (primary outcome measure, and measure1 of secondary outcome measure) | at 1 day after surgery. | 
| Measurement of intracranial hypertension with transcranial Doppler | we use the same methods and the same thresholds as those used during surgery (primary outcome measure, and measure1 of secondary outcome measure) | at 5 days after surgery. | 
| Measure of the optic nerve sheath diameter after surgery. | we use the same methods and the same thresholds as those used during surgery (primary outcome measure, and measure1 of secondary outcome measure) | at 5 days after surgery. | 
| The early appearance of neurological complications after surgery. | A monitoring with simultaneous collection of clinical, biological and ultrasound parameters, will be done. Neurological complications after surgery will be defined by the presence of at least one of the following criteria: Glasgow score < 14 in a non-sedated patient, behavioral disorders, agitation (evaluation according to the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) score), epilepsy, imaging or MRI scan. Pathological evolved compared to the preoperative including hemorrhagic or thrombotic cardiovascular event. Various confounding factors will be considered (serum sodium, serum tacrolimus, serum magnesium, ammonia, sedatives). | During the 5 days following surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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intracranial hypertension, liver transplantation, transcranial Doppler, optic nerve sheath diameter