The effects of beta blockade and clonidine on persistent injury-associated anemia.
BACKGROUND
Nonselective beta blockade (BB) and clonidine may abrogate catecholamine-mediated persistent injury-associated anemia. We hypothesized that critically ill trauma patients who received BB or clonidine would have favorable hemoglobin (Hb) trends when adjusting for operative blood loss (OBL), phlebotomy blood loss (PBL), and red blood cell (RBC) transfusion volumes, and that the effect would be greatest among the elderly, who have higher catecholamine levels.


METHODS
We performed a 4-y retrospective cohort analysis of 280 consecutive trauma patients with ICU stay ≥48 h and moderate/severe anemia. Patients who received BB or clonidine for ≥25% of their hospital stay were grouped as the BB/clonidine cohort (n = 84); all other patients served as controls (n = 196). Admission and discharge Hb were used to calculate ΔHb. OBL, PBL, and RBC volume were used to calculate adjusted ΔHb assuming 300 mL RBC = 1 g/dL Hb.


RESULTS
BB/clonidine and control patients had similar age, injury severity, comorbid illness, and admission Hb. BB/clonidine patients received fewer RBCs despite greater OBL, though neither association was statistically significant. BB/clonidine patients had higher discharge Hb (9.9 versus 9.5, P = 0.029) and adjusted ΔHb (+1.0 versus -0.8, P = 0.003). Hb curves separated after hospital day 10. The difference in adjusted ΔHb between groups increased with advanced age (all patients: 1.7, ≥50 y: 1.8, ≥60 y: 2.4, ≥70 y: 3.7).


CONCLUSIONS
Critically ill trauma patients receiving BB or clonidine had favorable Hb trends when accounting for OBL, PBL, and RBC transfusions. These findings support the hypothesis that BB and clonidine alleviate persistent injury-associated anemia, with strongest effects among the elderly.
['Loftus|Tyler J|TJ|', 'Rosenthal|Martin D|MD|', 'Croft|Chasen A|CA|', 'Smith|R Stephen|RS|', 'Moore|Frederick A|FA|', 'Brakenridge|Scott C|SC|', 'Efron|Philip A|PA|', 'Mohr|Alicia M|AM|']
D058647:Adrenergic alpha-2 Receptor Agonists D000319:Adrenergic beta-Antagonists D000367:Age Factors D000740:Anemia D016063:Blood Loss, Surgical D002395:Catecholamines D003000:Clonidine D016638:Critical Illness D004359:Drug Therapy, Combination D017707:Erythrocyte Transfusion D005260:Female D006454:Hemoglobins D006801:Humans D015601:Injury Severity Score D007362:Intensive Care Units D007902:Length of Stay D008297:Male D008875:Middle Aged D012189:Retrospective Studies D016896:Treatment Outcome D014947:Wounds and Injuries
Clonidine Anemia Trauma Elderly Aging Beta blocker Bone marrow Erythropoiesis