Administration of B-blockers may reduce mortality in critically ill patients.

A recent systematic review has found that in critically ill patients administering β-blockers appeared safe and reduced the mortality rate after initial hemodynamic stabilization. The study was published in the journal Annals of Medicine.' 

Critical illnesses like trauma, sepsis, etc. may lead to sympathetic system activation due to hemodynamic, metabolic, and other immunomodulatory changes. Exogenous catecholamines, such as vasopressors and inotropes may further increase sympathetic stimulation. Organ dysfunction and higher mortality were noticed with excessive adrenergic stress. β-Blockers may reduce the adrenergic burden, but they may also compromise perfusion to vital organs thus worsening organ dysfunction. Hence, researchers conducted a systematic review and meta-analysis of randomized controlled trials to assess the effect of treatment with β-blockers in critically ill adults. 

Using keywords databases like Ovid Medline, the Cochrane Central Register for Controlled Trials, and Scopus were searched.  As per the eligibility criteria, two independent reviewers screened, selected, and assessed the included articles. The risk of bias in eligible articles was assessed according to the Cochrane guidelines. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. 

Results

• 2410 critically ill patients from sixteen randomized controlled trials were included in the final review.
• A meta-analysis of 11 trials including 2103 patients showed a significant reduction in mortality in patients treated with β-blockers compared to control.
• There was no significant difference in mean arterial pressure or vasopressor load.
• Due to heterogenous reporting of outcomes, quality of life, biventricular ejection fraction, blood lactate levels, cardiac biomarkers, and mitochondrial function could not be included in the meta-analysis.  

Take-home messages: 

According to the current review and meta-analysis, a potential advantage of β-blocker treatment in critical illness.

In terms of hemodynamic stability and outcome, the administration of β-blockers to resuscitated patients in the ICU seems safe. 

Further studies are needed to understand the optimal target group of patients, timing of β-blocker treatment, choice of β-blocker, and choice of physiological and hemodynamic parameters to target during β-blocker treatment in critical illness. 

Further reading: https://doi.org/10.1080/07853890.2022.2098376 

Heliste M, Pettilä V, Berger D, Jakob SM, Wilkman E. Beta-blocker treatment in the critically ill: a systematic review and meta-analysis. Ann Med. 2022 Dec;54(1):1994-2010. doi: 10.1080/07853890.2022.2098376. PMID: 35838226; PMCID: PMC9291706.