CPP requalification

During a general anesthesia, people over 65 years old and hypertensive, have a modification of the vasoreactivity and their cerebral blood flow under vasoconstrictor such as norepinephrine or phenylephrine. We study the variation of the average velocity of the average cerebral artery under vasoconstrictor and during a modification of End Tidal CO2 (EtCO2) by transcranial Doppler.

General anesthesia induces a sympathetic block frequently leading to hypotension, especially in elderly and hypertensive patients. Currently, Phenylephrine (PE) and Norepinephrine (NE) are commonly used in clinical practice to address this arterial pressure drop. Their cardiovascular effects are not exactly the same, even though they both increase mean blood pressure.

Maintenance of mean arterial pressure is not the only hemodynamic goal during general anesthesia in the elderly. Cognitive disorders have been demonstrated during post-anesthetic awakening.

Cerebral hemodynamics is assessed by analyzing the speed of blood flow in the middle cerebral artery using transcranial Doppler (DTC). It measures the systolic and diastolic speed as well as the pulsatility index, which are predictive factors for lowering cerebral blood flow.

Inclusion Criteria:

• older over 65 years
• high blood pressure disease
• need general anesthesia
• need vasopressors : norepinephrine or phenylephrine
• temporal window of transcranial doppler is viable

Exclusion Criteria:

• Acute, valvular, rhythmic or ischemic cardiovascular pathology
• severe arthritis (stage 3)
• Intra-cranial pathology
• Significant carotid stenosis (> 40%) or carotid endarterectomy
• Cervical surgery
• Taking a premedication that can modify cerebral vasoreactivity
• Insulin-dependent diabetes for more than 10 years
• Person under judicial protection
• Opposition to data processing

population, older over 65 years and hypertensive blood pressure disease with general anesthesia in Tours Hospital in France.