Background: Chronic alcohol consumption is a prevalent issue. Healthcare professionals often discover their patient has an alcohol consumption issue when they are admitted to the hospital and no longer have access to alcohol. The global standard for treating alcohol withdrawal syndrome (AWS) symptoms are benzodiazepines; however this therapy is often inadequate to control symptoms of delirium in adult intensive care unit (ICU) patients due to an imbalance of inhibitory and excitatory neurotransmitters.

Objectives: The objective of the systematic review is to examine the clinical effectiveness of dexmedetomidine as an adjuvant to benzodiazepine-based therapy versus benzodiazepine-based therapy alone in decreasing the severity of delirium associated with AWS in adult ICU patients.

Inclusion criteria: This review considered studies that included adult ICU patients over the age of 18 who were experiencing delirium associated with alcohol withdrawal. Patients admitted to the ICU with the diagnosis of AWS were included in the study.This review considered studies that evaluated dexmedetomidine as an adjuvant therapy to benzodiazepine-based therapy, compared to the use of benzodiazepine-based therapy alone in ICU patients experiencing alcohol withdrawal delirium.This review considered randomized controlled trials, non-randomized controlled trials, quasi-experimental, before and after studies, prospective and retrospective cohort studies, case control studies, analytical cross sectional studies, case series, individual case reports and descriptive cross sectional studies for inclusion.The systematic review evaluated dexmedetomidine as an adjuvant to benzodiazepine-based therapy to decrease delirium severity in alcohol withdrawal in ICU patients. The general outcome of delirium severity was measured using the Clinical Institute Withdrawal Assessment Score - Revised (CIWA), the Ramsey scale, the Richmond Agitation Sedation Score (RASS) and the Confusion Assessment Method for the ICU (CAM-ICU).

Search strategy: The search strategy aimed to find both published and unpublished studies. A three-step search strategy was utilized in this review and included English language studies published after 1997. A search of Ovid/MEDLINE, EMBASE, Cochrane, Joanna Briggs Institute and nine other databases was conducted.

Methodological quality: Two independent reviewers using the Joanna Briggs Institute's standardized appraisal tool critically appraised the studies. A third independent reviewer was available to appraise studies if the two original reviewers disagreed in their assessments. There were no disagreements in findings between the two independent reviewers.

Data collection: Data was extracted using the standardized Joanna Briggs Institute's data extraction instruments.

Data synthesis: Statistical pooling was done using meta-analysis and findings are presented using a forest plot and narrative form.

Results: Four studies were included in the review, three retrospective case series and one prospective case series with a total sample size of 55 patients. Three studies used the CIWA score as the outcome measure and one study used the RASS score as the outcome measure. A meta-analysis of the three studies using the CIWA demonstrated that adjuvant use of dexmedetomidine with benzodiazepine-based therapy decreased CIWA scores (Weighted Mean Difference [WMD] -5.2, 95% Confidence Interval [CI] -6.24 to -4.16, p <0.0001). The final study using RASS scores reported improvement with adjuvant treatment with dexmedetomidine compared to benzodiazepine-based therapy alone.

Conclusions: The use of dexmedetomidine as an adjuvant to benzodiazepine-based therapy decreased delirium more effectively than benzodiazepine-based therapy alone in adult ICU patients experiencing alcohol withdrawal delirium as evidenced by a decrease in CIWA and RASS scores.

Implications for practice: In adult ICU patients who are experiencing alcohol withdrawal delirium that is not controlled with benzodiazepine-based therapy alone, healthcare providers should consider dexmedetomidine as an adjuvant to standard benzodiazepine-based therapy.

Implications for research: The use of dexmedetomidine in the management of delirium associated with alcohol withdrawal in adult ICU patients should be further studied via large scale randomized controlled trials.