Recovery of consciousness and functional outcome in moderate and severe traumatic brain injury

Kowalski RG, Hammond FM, Weintraub AH, et al. Recovery of Consciousness and Functional Outcome in Moderate and Severe Traumatic Brain Injury. JAMA Neurol. Published online March 01, 2021. doi:10.1001/jamaneurol.2021.0084

Key Points

Question  What are the trajectory of and factors associated with recovery of consciousness in patients with a disorder of consciousness (DOC) after traumatic brain injury (TBI)? 

Findings  In this cohort study of 17 470 patients with TBI, 57% of patients experienced initial loss of consciousness, which persisted after acute care treatment in 12% of patients. However, 98% of these patients recovered consciousness by the end of subsequent inpatient rehabilitation, and their trajectory of functional improvement mirrored that of patients with TBI who did not lose consciousness. 

Meaning  Results of this study indicated that most individuals who became comatose after moderate or severe TBI recovered consciousness in the short term and almost half of them regained functional independence, suggesting that caution is warranted in early decisions to withdraw or withhold treatment in patients with TBI and a DOC.

Abstract

Importance  Traumatic brain injury (TBI) leads to 2.9 million visits to US emergency departments annually and frequently involves a disorder of consciousness (DOC). Early treatment, including withdrawal of life-sustaining therapies and rehabilitation, is often predicated on the assumed worse outcome of disrupted consciousness. 

Objective  To quantify the loss of consciousness, factors associated with recovery, and return to functional independence in a 31-year sample of patients with moderate or severe brain trauma. 

Design, Setting, and Participants  This cohort study analyzed patients with TBI who were enrolled in the Traumatic Brain Injury Model Systems National Database, a prospective, multiyear, longitudinal database. Patients were survivors of moderate or severe TBI who were discharged from acute hospitalization and admitted to inpatient rehabilitation from January 4, 1989, to June 19, 2019, at 1 of 23 inpatient rehabilitation centers that participated in the Traumatic Brain Injury Model Systems program. Follow-up for the study was through completion of inpatient rehabilitation. 

Exposures  Traumatic brain injury. 

Main Outcomes and Measures  Outcome measures were Glasgow Coma Scale in the emergency department, Disability Rating Scale, posttraumatic amnesia, and Functional Independence Measure. Patient-related data included demographic characteristics, injury cause, and brain computed tomography findings. 

Results  The 17 470 patients with TBI analyzed in this study had a median (interquartile range [IQR]) age at injury of 39 (25-56) years and included 12 854 male individuals (74%). Of these patients, 7547 (57%) experienced initial loss of consciousness, which persisted to rehabilitation in 2058 patients (12%). Those with persisting DOC were younger; had more high-velocity injuries; had intracranial mass effect, intraventricular hemorrhage, and subcortical contusion; and had longer acute care than patients without DOC. Eighty-two percent (n = 1674) of comatose patients recovered consciousness during inpatient rehabilitation. In a multivariable analysis, the factors associated with consciousness recovery were absence of intraventricular hemorrhage (adjusted odds ratio [OR], 0.678; 95% CI, 0.532-0.863; P = .002) and intracranial mass effect (adjusted OR, 0.759; 95% CI, 0.595-0.968; P = .03). Functional improvement (change in total functional independence score from admission to discharge) was +43 for patients with DOC and +37 for those without DOC (P = .002), and 803 of 2013 patients with DOC (40%) became partially or fully independent. Younger age, male sex, and absence of intraventricular hemorrhage, intracranial mass effect, and subcortical contusion were associated with better functional outcome. Findings were consistent across the 3 decades of the database. 

Conclusions and Relevance  This study found that DOC occurred initially in most patients with TBI and persisted in some patients after rehabilitation, but most patients with persisting DOC recovered consciousness during rehabilitation. This recovery trajectory may inform acute and rehabilitation treatment decisions and suggests caution is warranted in consideration of withdrawing or withholding care in patients with TBI and DOC. ________________________________________________________________________

Most patients who become comatose after experiencing moderate or severe traumatic brain injury (TBI) recover consciousness in the short term — and nearly half regain functional independence, new research suggests. 

The study, which included more than 17,000 patients who were hospitalized with moderate and severe TBI over three decades, showed that even when they remained unconscious at the end of their initial acute hospital care and were admitted for subsequent inpatient rehabilitation, 82% recovered consciousness by rehab completion. 

"The results of our study, we think, show that caution is warranted in making decisions to withdraw or hold care in patients with these serious brain injuries," lead author Robert G. Kowalski, MBBCh, Department of Neurology, University of Colorado School of Medicine, Aurora, told Medscape Medical News. 

"A meaningful recovery is possible, even when loss of consciousness occurs after the brain injury," he added…

Historically, the prognosis of recovery for patients who have prolonged unconsciousness or disorders of consciousness (DOC) "has been perceived to be poor, with little hope for a return to independence," he said. 

Therefore, in a significant proportion of cases, decisions are made to withdraw or withhold life-sustaining therapies, and the patients subsequently die. "This in turn contributes to the perception of poor prognosis in severe TBI — a so-called 'self-fulfilling prophecy,' " Kowalski noted. 

The investigators evaluated the trajectory of, and factors associated with, recovery of consciousness and functional ability in patients with a DOC after moderate to severe TBI, focusing on the acute stage of emergent and critical care and subsequent inpatient rehabilitation. 

"We chose this period of care, including the initial hospitalization and subsequent inpatient rehabilitation, because this is the time window during which treating medical teams and families make critical decisions that may prolong life and affect longer-term outcome for these patients, and help determine how successfully they are able to return to independent living," Kowalski said…

However, 1674 comatose patients (82%) recovered consciousness (ability to follow commands) by the end of inpatient rehabilitation (median rehabilitation stay, 33 days). In addition, their trajectory of functional improvement mirrored that of patients with TBI who did not lose consciousness.

The investigators also observed the absence of specific signs of neuroanatomic injury on brain imaging, typically brain CT in the acute phase of treatment, including blood in the ventricles of the brain and severe midline shift of cerebral structures. This absence portends better prospects for recovery of consciousness and functional ability for these patients, the researchers note…

In an accompanying editorial, Jennifer Kim, MD, PhD, and Kevin Sheth, MD, Division of Neurocritical Care, Yale School of Medicine, New Haven, Connecticut, note that the study "further challenges our potential toward overly nihilistic notions of who may, or may not, ultimately recover consciousness long term" by showing that a large proportion of patients with persistent DOC recover during acute rehabilitation. 

"Other studies that followed up patients long term (not restricted to the inpatient rehabilitation period) corroborate the observation that recovery in TBI can occur 6 to 12 months after injury," they write.

The current study used one of the largest cohorts of patients with TBI available to assess recovery in the rehabilitation setting, and the "remarkable rate of recovery should give pause to practitioners who counsel families about potential recovery of DoC," write Kim and Sheth.

"If there are no concerning radiographic features, then practitioners should communicate the potential for delayed DoC recovery," they add. 

Echoing the investigators, the editorialists write that this study "adds to the TBI literature cautioning against withdrawal of life-sustaining therapy even when faced with prolonged DoC during hospitalization because there remains significant potential for recovery." 

"Defining both good and poor prognostic risk factors is critical to portending recovery. Future work must refine biomarker identification and use in patients with DoC to improve physician prognostication and avoid self-fulfilling prophecy," they conclude.

https://www.medscape.com/viewarticle/946867