Dexmedetomidine only regimen for long-term sedation is associated with reduced vasopressor requirements in septic shock patients: A retrospective cohort study from MIMIC-IV database

BACKGROUND: Previous studies have shown that dexmedetomidine (DEX) may be associated with reduced vasopressor requirements in septic shock patients, however, long-term DEX-only sedation in reducing vasopressor requirements is still controversial. METHODS: A retrospective study was conducted among patients with septic shock on mechanical ventilation using the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The primary outcome was the ratio of norepinephrine equivalent dose to mean arterial pressure (NEq/MAP) in the first 72 h after DEX or other sedatives for sedation. The secondary outcomes were key organ function parameters, 28-day mortality, and 90-day mortality. Univariate, propensity score matching (PSM), and generalized linear mixed model (GLMM) analyses were performed. RESULTS: DEX was associated with decreased NEq/MAP in the first 72 h (difference = 0.05, 95% CI = –0.02–0.08, p = 0.002) after adjusting for confounders in the GLMM analysis. The DEX group was also associated with a lower heart rate, cardiac output (CO), lactate level, aspartate transaminase (AST) level, and higher PaO(2)/FiO(2) ratio (p < 0.0125). Moreover, DEX only sedation was associated with reduced 90-day mortality (OR = 0.60, 95% CI = 0.37–0.94, p = 0.030). CONCLUSION: DEX may be associated with decreased vasopressor requirements, improved AST and PaO(2)/FiO(2) levels, and reduced 90-day mortality in patients with septic shock, which warrants further study.