Le propofol et l'AIVOC en neuro-anesthésie

Brain-scale cortico-cortical functional connectivity in the delta-theta band is a robust signature of conscious states: an intracranial and scalp EEG study

Long-range cortico-cortical functional connectivity has long been theorized to be necessary for conscious states. In the present work, we estimate long-range cortical connectivity in a series of intracranial and scalp EEG recordings experiments. In the two first experiments intracranial-EEG (iEEG) was recorded during four distinct states within the same individuals: conscious wakefulness (CW), rapid-eye-movement sleep (REM), stable periods of slow-wave sleep (SWS) and deep propofol anaesthesia (PA). We estimated functional connectivity using the following two methods: weighted Symbolic-Mutual-Information (wSMI) and phase-locked value (PLV). Our results showed that long-range functional connectivity in the delta-theta frequency band specifically discriminated CW and REM from SWS and PA. In the third experiment, we generalized this original finding on a large cohort of brain-injured patients. FC in the delta-theta band was significantly higher in patients being in a minimally conscious state (MCS) than in those being in a vegetative state (or unresponsive wakefulness syndrome). Taken together the present results suggest that FC of cortical activity in this slow frequency band is a new and robust signature of conscious states.

The KEEP SIMPLEST Study: Improving In-House Delays and Periinterventional Management in Stroke Thrombectomy-A Matched Pair Analysis

BACKGROUND AND PURPOSE

Although the treatment window for mechanical thrombectomy (MT) in patients with acute ischemic stroke (AIS) has been extended in recent years, it has been proven that recanalizing treatment must be administered as soon as possible. We present a new standard operating procedure (SOP) to reduce in-house delay, standardize periinterventional management and improve patient safety during MT.

METHODS

KEep Evaluating Protocol Simplification In Managing Periinterventional Light Sedation for Endovascular Stroke Treatment (KEEP SIMPLEST) was a prospective, single-center observational study aimed to compare aspects of periinterventional management in AIS patients treated according to our new SOP using a combination of esketamine and propofol with patients having been randomized into conscious sedation (CS) in the Sedation versus Intubation for Endovascular Stroke TreAtment (SIESTA) trial. Primary outcome was early neurological improvement at 24h using the National Institutes of Health Stroke Scale, and secondary outcomes were door-to-recanalization, recanalization grade, conversion rate and modified Rankin Scale (mRS) at 3 months.

RESULTS

Door-to-recanalization time (128.6 ± 69.47 min vs. 156.8 ± 75.91 min; p = 0.02), mean duration of MT (92.01 ± 52 min vs. 131.9 ± 64.03 min; p < 0.001), door-to-first angiographic image (51.61 ± 31.7 min vs. 64.23 ± 21.53 min; p = 0.003) and computed tomography-to-first angiographic image time (31.61 ± 20.6 min vs. 44.61 ± 19.3 min; p < 0.001) were significantly shorter in the group treated under the new SOP. There were no differences in early neurological improvement, mRS at 3 months or other secondary outcomes between the groups. Conversion rates of CS to general anesthesia were similar in both groups.

CONCLUSION

An SOP using a novel sedation regimen and optimization of equipment and procedures directed at a leaner, more integrative and compact periinterventional management can reduce in-house treatment delays significantly in stroke patients receiving thrombectomy in light sedation and demonstrated the safety and feasibility of our improved approach.

Exhaustive, one-year follow-up of subthalamic nucleus deep brain stimulation in a large, single-center cohort of parkinsonian patients

OBJECTIVE

To prospectively assess the impact of subthalamic nucleus (STN) deep brain stimulation (DBS) at 12 months after surgery in a series of 100 consecutive patients treated in a single center. The primary objective was to describe the clinical outcome in terms of efficacy and tolerance in STN-DBS patients. A secondary objective was to discuss presurgery clinical characteristics a posteriori as a function of outcome.

METHODS

One hundred and three consecutive patients with severe Parkinson's disease received bilateral STN-DBS in our clinic between May 1998 and March 2003. Clinical assessment was performed before and 12 months after surgery and was based on the Unified Parkinson's Disease Rating Scale, Parts II, III, and IV A; the Schwab and England Scale; and cognitive evaluation. Patient-rated overall improvement was also evaluated.

RESULTS

Twelve months after surgery, the Unified Parkinson's Disease Rating Scale Part III score decreased by 43%, the Unified Parkinson's Disease Rating Scale Part II score (activities of daily living) fell by 34%, and the severity of dyskinesia-related disability decreased by 61%. The main surgical complications after STN-DBS were as follows: infection (n = 7), intracerebral hematoma (n = 5), electrode fracture (n = 4), and incorrect lead placement (n = 8). We observed cognitive decline and depression in 7.7 and 18% of the patients, respectively. The mean patient-rated overall improvement score was 70.7%.

CONCLUSION

The efficacy and safety of STN-DBS in our center's large cohort of Parkinsonian patients are generally similar to the results obtained by other groups, albeit at the lower limit of the range of reported values. In contrast to efficacy, the occurrence of adverse events cannot be predicted. Younger patients with Parkinson's disease (i.e., those younger than 60 yr) often show an excellent response to levodopa. However, in view of our data on overall patient satisfaction and the occurrence of adverse events, we suggest that older patients (but not those older than 70 yr) and less dopa-sensitive patients (but not those with a response <50%) should still be offered the option of STN-DBS.