Efficacy of beta-blockade after isolated blunt head injury: does race matter?

Beta-Blocker Therapy in Patients With Severe Traumatic Brain Injury: A Systematic Review and Meta-Analysis

INTRODUCTION

Traumatic brain injury (TBI), a leading cause of morbidity and mortality among trauma patients worldwide, poses the risk of secondary neurological insult due to significant catecholamine surge. We aim to investigate the effectiveness and outcomes of beta-blocker administration in patients with severe TBI.

METHODS

A search through PubMed, EMBASE, JAMA network, and Google Scholar databases was conducted for relevant peer-reviewed original studies published before February 15, 2022. A standard random-effects model was used, as justified by a high Cohen's Q test.

RESULTS

Twelve studies met inclusion criteria and were included in the meta-analysis. Severe TBI patients who were administered beta-blockers had a significantly reduced incidence of in-hospital mortality compared to the non-beta-blocker group (14.5% vs 19.2%). However, the beta-blocker group was reported to have a significantly greater number of ventilator days (5.58 vs 2.60 days). Similarly, intensive care unit (9.00 vs 6.84 days) and hospital (17.30 vs 11.02 days) lengths of stay (LOS) were increased in the beta-blocker group compared to those who were not administered beta-blocker therapy, but only the difference in hospital-LOS was significant.

CONCLUSIONS

Beta-blockers have significantly decreased in-hospital mortality in patients with severe TBI despite being associated with an increase in ventilator days and hospital-LOS. The administration of beta-blocker therapy in the management of severe TBI may be warranted and should be discussed in future guidelines.

Beta blocker use in traumatic brain injury based on the high-sensitive troponin status (BBTBBT): methodology and protocol implementation of a double-blind randomized controlled clinical trial

Background

Beta-adrenergic receptor blockers (BB) play an important role in the protection of organs that are susceptible for secondary injury due to stress-induced adrenergic surge. However, the use of BB in traumatic brain injury (TBI) patients is not yet the standard of care which necessitates clear scientific evidence to be used. The BBTBBT study aims to determine whether early administration of propranolol based on the high-sensitive troponin T(HsTnT) status will improve the outcome of TBI patients. We hypothesized that early propranolol use is effective in reducing 10- and 30-day mortality in TBI patients. Secondary outcomes will include correlation between serum biomarkers (troponin, epinephrine, cytokines, enolase, S100 calcium binding protein B) and the severity of injury and the impact of BB use on the duration of hospital stay and functional status at a 3-month period.

Methods

The BBTBBT study is a prospective, randomized, double-blinded, placebo-controlled three-arm trial of BB use in mild-to-severe TBI patients based on the HsTnT status. All enrolled patients will be tested for HsTnT at the first 4 and 6 h post-injury. Patients with positive HsTnT will receive BB if there is no contraindication (group 1). Patients with negative HsTnT will be randomized to receive either propranolol (group 2) or placebo (group 3). The time widow for receiving the study treatment is the first 24 h post-injury.

Discussion

Early BB use may reduce the catecholamine storm and subsequently the cascade of immune and inflammatory changes associated with TBI. HsTnT could be a useful fast diagnostic and prognostic tool in TBI patients. This study will be of great clinical interest to improve survival and functional outcomes of TBI patients.

Trial registration

ClinicalTrials.gov NCT04508244. Registered on 7 August 2020. Recruitment started on 29 December 2020 and is ongoing.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05872-8.

β-Blockers for traumatic brain injury: A systematic review and meta-analysis

BACKGROUND

Paroxysmal sympathetic hyperactivity (PSH) and catecholamine surge, which are associated with poor outcome, may be triggered by traumatic brain injury (TBI).β Adrenergic receptor blockers (β-blockers), as potential therapeutic agents to prevent paroxysmal sympathetic hyperactivity and catecholamine surge, have been shown to improve survival after TBI. The principal aim of this study was to investigate the effect of β-blockers on outcomes in patients with TBI.

METHODS

For this systematic review and meta-analysis, we searched MEDLINE, EMBASE, and Cochrane Library databases from inception to September 25, 2020, for randomized controlled trials, nonrandomized controlled trials, and observational studies reporting the effect of β-blockers on the following outcomes after TBI: mortality, functional measures, and cardiopulmonary adverse effects of β-blockers (e.g., hypotension, bradycardia, and bronchospasm). With use of random-effects model, we calculated pooled estimates, confidence intervals (CIs), and odds ratios (ORs) of all outcomes.

RESULTS

Fifteen studies with 12,721 patients were included. Exposure to β-blockers after TBI was associated with a significant reduction in adjusted in-hospital mortality (OR, 0.39; 95% CI, 0.30-0.51; I2 = 66.3%; p < 0.001). β-Blockers significantly improved the long-term (≥6 months) functional outcome (OR, 1.75; 95% CI, 1.09-2.80; I2 = 0%; p = 0.02). Statistically significant difference was not seen for cardiopulmonary adverse events (OR, 0.91; 95% CI, 0.55-1.50; I2 = 25.9%; p = 0.702).

CONCLUSION

This meta-analysis demonstrated that administration of β-blockers after TBI was safe and effective. Administration of β-blockers may therefore be suggested in the TBI care. However, more high-quality trials are needed to investigate the use of β-blockers in the management of TBI.

LEVEL OF EVIDENCE

Systematic review and meta-analysis, level III.

Beta-adrenergic blockade for attenuation of catecholamine surge after traumatic brain injury: a randomized pilot trial

Background

Beta-blockers have been proven in multiple studies to be beneficial in patients with traumatic brain injury. Few prospective studies have verified this and no randomized controlled trials. Additionally, most studies do not titrate the dose of beta-blockers to therapeutic effect. We hypothesize that propranolol titrated to effect will confer a survival benefit in patients with traumatic brain injury.

Methods

A randomized controlled pilot trial was performed during a 24-month period. Patients with traumatic brain injury were randomized to propranolol or control group for a 14-day study period. Variables collected included demographics, injury severity, physiologic parameters, urinary catecholamines, and outcomes. Patients receiving propranolol were compared with the control group.

Results

Over the study period, 525 patients were screened, 26 were randomized, and 25 were analyzed. Overall, the mean age was 51.3 years and the majority were male with blunt mechanism. The mean Injury Severity Score was 21.8 and median head Abbreviated Injury Scale score was 4. Overall mortality was 20.0%. Mean arterial pressure was higher in the treatment arm as compared with control (p=0.021), but no other differences were found between the groups in demographics, severity of injury, severity of illness, physiologic parameters, or mortality (7.7% vs. 33%; p=0.109). No difference was detected over time in any variables with respect to treatment, urinary catecholamines, or physiologic parameters. Glasgow Coma Scale (GCS), Sequential Organ Failure Assessment, and Acute Physiology and Chronic Health Evaluation scores all improved over time. GCS at study end was significantly higher in the treatment arm (11.7 vs. 8.9; p=0.044). Finally, no difference was detected with survival analysis over time between groups.

Conclusions

Despite not being powered to show statistical differences between groups, GCS at study end was significantly improved in the treatment arm and mortality was improved although not at a traditional level of significance. The study protocol was safe and feasible to apply to an appropriately powered larger multicenter study.

Level of evidence

Level 2—therapeutic.

Beta blockers in critically ill patients with traumatic brain injury: Results from a multicenter, prospective, observational American Association for the Surgery of Trauma study

BACKGROUND

Beta blockers, a class of medications that inhibit endogenous catecholamines interaction with beta adrenergic receptors, are often administered to patients hospitalized after traumatic brain injury (TBI). We tested the hypothesis that beta blocker use after TBI is associated with lower mortality, and secondarily compared propranolol to other beta blockers.

METHODS

The American Association for the Surgery of Trauma Clinical Trial Group conducted a multi-institutional, prospective, observational trial in which adult TBI patients who required intensive care unit admission were compared based on beta blocker administration.

RESULTS

From January 2015 to January 2017, 2,252 patients were analyzed from 15 trauma centers in the United States and Canada with 49.7% receiving beta blockers. Most patients (56.3%) received the first beta blocker dose by hospital day 1. Those patients who received beta blockers were older (56.7 years vs. 48.6 years, p < 0.001) and had higher head Abbreviated Injury Scale scores (3.6 vs. 3.4, p < 0.001). Similarities were noted when comparing sex, admission hypotension, mean Injury Severity Score, and mean Glasgow Coma Scale. Unadjusted mortality was lower for patients receiving beta blockers (13.8% vs. 17.7%, p = 0.013). Multivariable regression determined that beta blockers were associated with lower mortality (adjusted odds ratio, 0.35; p < 0.001), and propranolol was superior to other beta blockers (adjusted odds ratio, 0.51, p = 0.010). A Cox-regression model using a time-dependent variable demonstrated a survival benefit for patients receiving beta blockers (adjusted hazard ratio, 0.42, p < 0.001) and propranolol was superior to other beta blockers (adjusted hazard ratio, 0.50, p = 0.003).

CONCLUSION

Administration of beta blockers after TBI was associated with improved survival, before and after adjusting for the more severe injuries observed in the treatment cohort. This study provides a robust evaluation of the effects of beta blockers on TBI outcomes that supports the initiation of a multi-institutional randomized control trial.

LEVEL OF EVIDENCE

Therapeutic/care management, level III.

Predictive value of positive high-sensitivity troponin T in intubated traumatic brain injury patients

OBJECTIVEThe clinical relevance of high-sensitivity troponin T (HsTnT) in trauma patients is not well explored. In this study, the authors aimed to study the predictive value of serum HsTnT in intubated patients who had sustained traumatic brain injury (TBI).METHODSA retrospective analysis was conducted for all intubated TBI patients between 2010 and 2014 at a national level 1 trauma center. Data were analyzed and compared based on the HsTnT status on admission (group 1, negative results; and group 2, positive results). Receiver operating characteristic curves were used to determine sensitivity, specificity, and cutoff level of HsTnT to predict mortality. Time to earlier discharge from hospital or death was modeled using Cox proportional hazard models to describe the relationship between HsTnT and in-hospital mortality.RESULTSOf the 826 intubated TBI patients, 490 underwent HsTnT testing; 65.7% had positive HsTnT results. Patients in group 2 had a higher Injury Severity Score (p = 0.001) and head Abbreviated Injury Scale (AIS) score (p = 0.004) than those in group 1. In addition, group 2 patients were more likely to have lower Glasgow Coma Scale scores (p = 0.001) and more likely to experience intraventricular hemorrhage, brain edema, pneumonia, and sepsis (p = 0.001). HsTnT values positively correlated with head AIS score (r = 0.19, p = 0.001) and varied by the type of lesion and time to death. Ventilator days and length of hospital stay were more prolonged in group 2 patients (p = 0.001). Area under the curve (AUC) analysis showed that HsTnT ≥ 26.5 ng/L predicted all-cause mortality (AUC 0.75, 95% CI 0.699-0.801) with 80% sensitivity. Positive HsTnT was an independent predictor of mortality in multivariate models (adjusted OR 3.10, 95% CI 1.308-7.351) even after excluding chest injury (adjusted OR 4.18, 95% CI 1.320-13.231).CONCLUSIONSPositive HsTnT results are associated with poor outcomes in intubated patients with TBI. In this subset of patients, measuring serum HsTnT on admission is a useful tool for early risk stratification and expedited care; however, further prospective studies are warranted.

Serum cardiac troponins as prognostic markers in patients with traumatic and non-traumatic brain injuries: A meta-analysis

OBJECTIVE

The association between brain injury and elevated serum cardiac troponin (cTn) remains poorly understood. We conducted a systematic review and meta-analysis to evaluate whether elevated cTn increases the risk of mortality in patients with traumatic (TBI) or non-traumatic brain injury (NT-BI).

METHODS

Cochrane Library, MEDLINE, PubMed, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), WHO International Clinical Trials Registry Platform, and Google scholar databases, and clinicaltrials.gov were searched for a retrospective, prospective and randomized clinical trials (RCT) or quasi-RCT studies that assessed the effect of elevated cTn (conventional or high sensitive assay) on the outcomes of brain injury patients. The main outcome of interest was mortality. Two authors independently abstracted the data using a data collection form. Results from different studies were pooled for analysis, whenever appropriate. The total number of patients pooled was 2435, of which 916 had elevated cTn and 1519 were in control group.

RESULTS

Out of 691 references identified through the search, 8 analytical studies met inclusion criteria. Among both types of brain injuries, an elevated cTn was associated with a higher mortality with an overall pooled odd ratio (OR) of 3.37 (95% CI 2.13-5.36). The pooled OR for mortality was 3.31 (95% CI 1.99-5.53) among patients with TBI and 3.36 (95% CI 1.32-8.6) among patients with NT-BI.

CONCLUSIONS

Pooled analysis indicates that elevated cTn is significantly associated with a high mortality in patients with TBI and NT-BI. Prospective clinical trials are needed to support these findings and to inform a biomarker risk stratification regardless of the mechanism of injury.

Brain-Heart Interactions in Traumatic Brain Injury

The cardiovascular manifestations associated with nontraumatic head disorders are commonly known. Similar manifestations have been reported in patients with traumatic brain injury (TBI); however, the underlying mechanisms and impact on the patient's clinical outcomes are not well explored. The neurocardiac axis theory and neurogenic stunned myocardium phenomenon could partly explain the brain-heart link and interactions and can thus pave the way to a better understanding and management of TBI. Several observational retrospective studies have shown a promising role for beta-adrenergic blockers in patients with TBI in reducing the overall TBI-related mortality. However, several questions remain to be answered in clinical randomized-controlled trials, including population selection, beta blocker type, dosage, timing, and duration of therapy, while maintaining the optimal mean arterial pressure and cerebral perfusion pressure in patients with TBI.

Beta-blockers and Traumatic Brain Injury: A Systematic Review, Meta-analysis, and Eastern Association for the Surgery of Trauma Guideline

OBJECTIVE

To determine if beta-(β)-blockers improve outcomes after acute traumatic brain injury (TBI).

BACKGROUND

There have been no new inpatient pharmacologic therapies to improve TBI outcomes in a half-century. Treatment of TBI patients with β-blockers offers a potentially beneficial approach.

METHODS

Using MEDLINE, EMBASE, and CENTRAL databases, eligible articles for our systematic review and meta-analysis (PROSPERO CRD42016048547) included adult (age ≥ 16 years) blunt trauma patients admitted with TBI. The exposure of interest was β-blocker administration initiated during the hospitalization. Outcomes were mortality, functional measures, quality of life, cardiopulmonary morbidity (e.g., hypotension, bradycardia, bronchospasm, and/or congestive heart failure). Data were analyzed using a random-effects model, and represented by pooled odds ratio (OR) with 95% confidence intervals (CI) and statistical heterogeneity (I).

RESULTS

Data were extracted from 9 included studies encompassing 2005 unique TBI patients with β-blocker treatment and 6240 unique controls. Exposure to β-blockers after TBI was associated with a reduction of in-hospital mortality (pooled OR 0.39, 95% CI: 0.27-0.56; I = 65%, P < 0.00001). None of the included studies examined functional outcome or quality of life measures, and cardiopulmonary adverse events were rarely reported. No clear evidence of reporting bias was identified.

CONCLUSIONS

In adults with acute TBI, observational studies reveal a significant mortality advantage with β-blockers; however, quality of evidence is very low. We conditionally recommend the use of in-hospital β-blockers. However, we recommend further high-quality trials to answer questions about the mechanisms of action, effectiveness on subgroups, dose-response, length of therapy, functional outcome, and quality of life after β-blocker use for TBI.

Therapeutic effect of beta-blocker in patients with traumatic brain injury: A systematic review and meta-analysis

OBJECTIVE

β-Blocker exposure has been shown to reduce mortality in traumatic brain injury (TBI); however, the efficacy of β-blockers remains inconclusive. Therefore, a meta-analysis was conducted in this paper to evaluate the safety and efficacy of β-blocker therapy on patients with TBI.

METHODS

The electronic databases were systemically retrieved from construction to February 2017. The odds ratio (OR), mean difference (MD) and 95% confidence intervals (CI) were determined.

RESULTS

A total of 13 observational cohort studies involving 15,734 cases were enrolled. The results indicated that β-blocker therapy had remarkably reduced the in-hospital mortality (OR 0.33; 95% CI 0.27-0.40; p<0.001). However, β-blocker therapy was also associated with increased infection rate (OR 2.01; 95% CI 1.50-2.69; p<0.001), longer length of stay (MD=7.40; 95% CI=4.39, 10.41; p<0.001) and ICU stay (MD=3.52; 95% CI=1.56, 5.47; p<0.001). In addition, β-blocker therapy also led to longer period of ventilator support (MD=2.70; 95% CI=1.81, 3.59; p<0.001).

CONCLUSION

The meta-analysis demonstrates that β-blockers are effective in lowering mortality in patients with TBI. However, β-blocker therapy has markedly increased the infection rate and requires a longer period of ventilator support, intensive care management as well as length of stay.

Impact of Beta-Blockers on Nonhead Injured Trauma Patients

Catecholamine surge after traumatic injury may lead to dysautonomia with increased morbidity. Small retrospective studies have shown potential benefit of beta-blockers (BB) in trauma patients with and without traumatic brain injury (TBI). This study evaluates a large multiply injured cohort without TBI that received BB. Patients were identified from the trauma registry from January 1, 2003 to December 31, 2011. Patients who received >1 dose of BB were compared to controls. Patients with TBI, length of stay (LOS) < 2 days, and prehospital BB were excluded. Outcomes were mortality, intensive care unit (ICU) LOS, and LOS. Stepwise multivariable regression was used to identify variables significantly associated with mortality. During the study period, 19,151 eligible patients were admitted. The mean age was 39 years. Most were male (74%) and most sustained blunt mechanism (75%). A total of 1854 (11%) patients received BB. BB patients had longer LOS (16 vs 6 days), ICU LOS (7 vs 1 days), and higher mortality (2.8 vs 0.5%) (all P < 0.001). Multivariable regression demonstrated no benefit to BB after adjusting for potential confounding characteristics [odds ratio (OR) 0.952; confidence interval (CI) 0.620–1.461]. In conclusion, in this largest study to date, patients receiving BB were older, more severely injured, and had a higher mortality. Unlike TBI patients, multivariable regression showed no benefit from BB in this population.