Factors affecting postoperative short-term improvement of consciousness level in patients with prolonged disorders of consciousness after severe traumatic brain injury / 中华创伤杂志

Objective:To investigate the factors affecting postoperative short-term improvement of consciousness level in patients with prolonged disorders of consciousness after severe traumatic brain injury (sTBI).Methods:A case-control study was conducted to analyze the clinical data of 55 patients with prolonged disorders of consciousness after sTBI admitted to Beijing Tiantan Hospital Affiliated to Capital Medical University and Seventh Medical Center of PLA General Hospital from September 2021 to September 2022. There were 33 males and 22 females, with the age range of 13-68 years [(43.0±15.5)years]. All patients were assessed for the consciousness level using the coma recovery scale-revision (CRS-R) preoperatively and within 48 hours postoperatively. A total of 33 patients were observed in vegetative state and 22 in minimally conscious state preoperatively. The consciousness level was found to be improved in 26 patients (consciousness- improved group), but not improved in the remaining 29 patients (consciousness-unimproved group). Indicators were documented including gender, age, cause of injury, Glasgow coma score (GCS) on admission, course of injury, preoperative consciousness level, operation mode, operation time, intraoperative fluid replenishment, intraoperative urine volume, intraoperative bleeding volume, American Society of Anesthesiologists grade, analgesic regimen and sedation maintenance drugs. A univariate analysis was conducted first to assess those indicators′ correlation with postoperative short-term improvement of consciousness level in patients with prolonged disorders of consciousness after sTBI. Multivariate Logistic regression analysis was then used to determine the independent risk factors for their postoperative short-term improvement of consciousness level.Results:Univariate analysis showed that GCS on admission, course of injury, preoperative consciousness level and analgesic regimen were correlated with short-term improvement of postoperative consciousness level in patients with prolonged disorders of consciousness after sTBI (all P<0.05), whereas gender, age, cause of injury, operation mode, operation time, intraoperative fluid replenishment, intraoperative urine volume, intraoperative bleeding volume, American Society of Anesthesiologists grade and sedation maintenance drugs showed no relation to the improvement of postoperative consciousness level (all P>0.05). Multivariate Logistic regression analysis showed that the GCS ≥7 points on admission ( OR=0.06, 95% CI 0.01, 0.36, P<0.01), preoperative minimally conscious state ( OR=0.09, 95% CI 0.02, 0.40, P<0.01) and intraoperative use of Sufentanil combined with Remifentanil ( OR=0.07, 95% CI 0.01, 0.43, P<0.01) were significantly correlated with postoperative improvement of consciousness level. Conclusion:The GCS on admission (≥7 points), preoperative minimally conscious state and intraoperative use of Sufentanil combined with Remifentanil are independent risk factors affecting short-term postoperative improvement of consciousness level in patients with prolonged disorders of consciousness after sTBI.

Current Status of Neuromodulatory Therapies for Disorders of Consciousness / 神经科学通报·英文版

Treatment for disorders of consciousness (DOCs) is still a Gordian knot. Evidence-based guidelines on the treatment of DOC patients are not currently available, while neuromodulation techniques are seen as a potential treatment. Multiple neuromodulation therapies have been applied. This article reviews the most relevant studies in the literature in order to describe a clear picture of the current state of neuromodulation therapies that could be used to treat DOC patients. Both invasive and non-invasive brain stimulation is discussed. Significant behavioral improvements in prolonged DOCs under neuromodulation therapies are rare. The efficacy of various such therapies remains a matter of debate. Further clinical investigations of existing techniques in larger samples properly controlling for spontaneous recovery are needed, and new approaches are awaited.

Spinal Cord Stimulation Frequency Influences the Hemodynamic Response in Patients with Disorders of Consciousness / 神经科学通报·英文版

Spinal cord stimulation (SCS) is a promising technique for treating disorders of consciousness (DOCs). However, differences in the spatio-temporal responsiveness of the brain under varied SCS parameters remain unclear. In this pilot study, functional near-infrared spectroscopy was used to measure the hemodynamic responses of 10 DOC patients to different SCS frequencies (5 Hz, 10 Hz, 50 Hz, 70 Hz, and 100 Hz). In the prefrontal cortex, a key area in consciousness circuits, we found significantly increased hemodynamic responses at 70 Hz and 100 Hz, and significantly different hemodynamic responses between 50 Hz and 70 Hz/100 Hz. In addition, the functional connectivity between prefrontal and occipital areas was significantly improved with SCS at 70 Hz. These results demonstrated that SCS modulates the hemodynamic responses and long-range connectivity in a frequency-specific manner (with 70 Hz apparently better), perhaps by improving the cerebral blood volume and information transmission through the reticular formation-thalamus-cortex pathway.

Spatial Properties of Mismatch Negativity in Patients with Disorders of Consciousness / 神经科学通报·英文版

In recent decades, event-related potentials have been used for the clinical electrophysiological assessment of patients with disorders of consciousness (DOCs). In this paper, an oddball paradigm with two types of frequency-deviant stimulus (standard stimuli were pure tones of 1000 Hz; small deviant stimuli were pure tones of 1050 Hz; large deviant stimuli were pure tones of 1200 Hz) was applied to elicit mismatch negativity (MMN) in 30 patients with DOCs diagnosed using the JFK Coma Recovery Scale-Revised (CRS-R). The results showed that the peak amplitudes of MMN elicited by both large and small deviant stimuli were significantly different from baseline. In terms of the spatial properties of MMN, a significant interaction effect between conditions (small and large deviant stimuli) and electrode nodes was centered at the frontocentral area. Furthermore, correlation coefficients were calculated between MMN amplitudes and CRS-R scores for each electrode among all participants to generate topographic maps. Meanwhile, a significant negative correlation between the MMN amplitudes elicited by large deviant stimuli and the CRS-R scores was also found at the frontocentral area. In consequence, our results combine the above spatial properties of MMN in patients with DOCs, and provide a more precise location (frontocentral area) at which to evaluate the correlation between clinical electrophysiological assessment and the level of consciousness.