A Brief Overview of the Coma Recovery Scale–Revised: Updates From the COMBI

A neurophysiological profiling of the heartbeat-evoked potential in severe acquired brain injuries: A focus on unconsciousness

Unconsciousness in severe acquired brain injury (sABI) patients occurs with different cognitive and neural profiles. Perturbational approaches, which enable the estimation of proxies for brain reorganization, have added a new avenue for investigating the non-behavioural diagnosis of consciousness. In this prospective observational study, we conducted a comparative analysis of the topological patterns of heartbeat-evoked potentials (HEP) between patients experiencing a prolonged disorder of consciousness (pDoC) and patients emerging from a minimally consciousness state (eMCS). A total of 219 sABI patients were enrolled, each undergoing a synchronous EEG-ECG resting-state recording, together with a standardized consciousness diagnosis. A number of graph metrics were computed before/after the HEP (Before/After) using the R-peak on the ECG signal. The peak value of the global field power of the HEP was found to be significantly higher in eMCS patients with no difference in latency. Power spectrum was not able to discriminate consciousness neither Before nor After. Node assortativity and global efficiency were found to vary with different trends at unconsciousness. Lastly, the Perturbational Complexity Index of the HEP was found to be significantly higher in eMCS patients compared with pDoC. Given that cortical elaboration of peripheral inputs may serve as a non-behavioural determinant of consciousness, we have devised a low-cost and translatable technique capable of estimating causal proxies of brain functionality with an endogenous, non-invasive stimulus. Thus, we present an effective means to enhance consciousness assessment by incorporating the interaction between the autonomic nervous system (ANS) and central nervous system (CNS) into the loop.

Decannulation After a Severe Acquired Brain Injury

OBJECTIVE

To identify the effect of some clinical characteristics of severe acquired brain injury (sABI) patients on decannulation success during their intensive rehabilitation unit (IRU) stay.

DESIGN

Nonconcurrent cohort study.

SETTING

Don Gnocchi Foundation Institute.

PARTICIPANTS

Patients (N=351) with sABI and tracheostomy were retrospectively selected from the database of the IRU of the Don Gnocchi Foundation Institute.

MAIN OUTCOME MEASURES

Potential predictors of decannulation were screened from variables collected at admission during clinical examination, conducted by trained and experienced examiners. The association between clinical characteristics and decannulation status was investigated through a Cox regression model. Kaplan-Meier curves were then created for time-event analysis.

RESULTS

Among the patients (mean age, 64.1±15.5y), 54.1% were decannulated during their IRU stay. Absence of pulmonary infections (P<.001), sepsis (P=.001), tracheal alteration at the fibrobronchoscopy examination (P=.004) and a higher Coma Recovery Scale-Revised (CRS-R) score (P<.001) or a better state of consciousness at admission (P=.001) were associated with a higher probability of decannulation.

CONCLUSIONS

Fibrobronchoscopy assessment of patency of airways and accurate evaluation of the state of consciousness using the CRS-R are relevant in this setting of care to better identify patients who are more likely to have the tracheostomy tube removed. These results may help clinicians choose the appropriate timing and intensity of rehabilitation interventions and plan for discharge.

Improvement on the Coma Recovery Scale-Revised During the First Four Weeks of Hospital Stay Predicts Outcome at Discharge in Intensive Rehabilitation After Severe Brain Injury

OBJECTIVES

To evaluate the prognostic utility of serial assessment on the Coma Recovery Scale-Revised (CRS-R) during the first 4 weeks of intensive rehabilitation in patients surviving a severe brain injury.

DESIGN

Prospective cohort study.

SETTING

An intensive rehabilitation unit.

PARTICIPANTS

Patients (N=110) consecutively admitted to the intensive rehabilitation unit. Inclusion criteria were (1) a diagnosis of unresponsive wakefulness syndrome (UWS) or minimally conscious state (MCS) caused by an acquired brain injury, and (2) aged >18 years.

INTERVENTIONS

All patients underwent clinical evaluations using the Italian version of the CRS-R during the first month of hospital stay.

MAIN OUTCOME MEASURES

Behavioral classification on the CRS-R and the score on the Glasgow Outcome Scale (GOS) at final discharge. Patients transitioning from UWS to MCS or emergence from MCS (E-MCS), and from MCS to E-MCS were classified as patients with improved responsiveness (IR).

RESULTS

After a mean ± SD hospital stay of 5.3±2.7 months, 59 of 110 patients (53.6%) achieved IR. In the multivariable analysis, a higher CRS-R score change at week 4 (odds ratio =1.99; 95% confidence interval [CI], 1.49-2.66; P<.001) was the only significant predictor of IR at discharge. Fifty-three patients (48.2%) were classified as severely impaired at discharge (GOS=3). In the multivariable analysis, higher GOS scores were related to a higher CRS-R score at admission (B=.051; 95% CI, .027-.074; P<.001), a higher CRS-R score change at week 4 (B=.087; 95% CI, .064-.110; P<.001), and an absence of severe infections (B=-.477; 95% CI, -.778 to -.176; P=.002).

CONCLUSIONS

An improvement on the total CRS-R score and on different subscales across the first 4 weeks of inpatient rehabilitation discriminates patients who will have a better outcome at discharge, providing information for rehabilitation planning and for communication with patients and their caregivers.

A validation of the Polish version of the Coma Recovery Scale-Revised (CRSR)

PRIMARY OBJECTIVE

The aim of this study was to determine the validity of the Polish version of the Coma Recovery Scale-Revised (CRS-R).

METHODS AND DESIGN

Two trained raters, A and B, administered CRS-R on a group of 20 patients with severe brain injury (median age ± SD, 38.0 ± 14.39 years). Both rater A and rater B completed their assessment on day 1, and rater A repeated their assessment on day 2. Inter-rater and test-retest reliability were evaluated with an intra-class correlation coefficient and Spearman rank correlation. Internal consistency was estimated with Cronbach's α. Agreement in diagnostic impression was determined using Cohen's κ.

RESULTS

Inter-rater reliability for CRS-R total scores and test-retest reliability was excellent: (ρ = 0.76, p < 0.001) and (ρ = 0.92, p < 0.001), respectively. Inter-rater diagnostic agreement was good (κ = 0.72, p < 0.001). Inter-rater reliability for subscales was fair to excellent. Internal consistency was excellent (Cronbach's α = 0.85).

CONCLUSION

The Polish version of CRS-R can be administered reliably by trained raters and can successfully differentiate between vegetative state (VS), minimally conscious (MCS), and patients emerging from a minimally conscious state (EMCS).