Dexmedetomidine use in ICU sedation and postoperative recovery in elderly patients post cardiac surgery (DIRECT)

Abstract Objective This study examined recovery, delirium and neurocognitive outcome in elderly patients receiving dexmedetomidine or propofol sedation after undergoing cardiac surgery. Design Open-label randomised trial. Setting Single centre. Participants 70 patients over the age of 75 without English language limitations and Mini Mental State Examination scores >20. Interventions Patients received either propofol (group P) or dexmedetomidine (group D) post-operatively until normothermic and haemodynamically stable. Measurements and Main Results Quality of recovery (QoR) was measured by the QoR-40 questionnaire on post-operative day (POD) 3. Secondary outcomes were incidence/duration of delirium, time to extubation, length of hospital stay, hospital mortality rate, and post-operative quality of life (QoL)/neurocognitive disorder (measured by SF-36 (performed at baseline and 6-months post-operatively)/MCAS (performed at baseline, POD5 and 6-months post-operatively) questionnaires respectively). 67 patients completed the trial. There was no significant difference in QoR-40 scores ([95% CI -7.6081 to 10.9781], p=1.000), incidence of delirium (group P, 42%; group D 24%; p=0.191), mean hospital stay ([95% CI -5.4838 to 1.5444); p=0.297), mean time to extubation ([95% CI -19.2513 to 7.5561]; p=0.866), or mean duration of delirium ([95% CI -4.3065 to 1.067]; p=0.206) between groups. No patients died in hospital. There was no significant difference in changes in SF-36 or MCAS scores over time between groups. There was a decline in MCAS score from pre-operatively to POD5 in group P ([95% CI -8.95725 to -2.61775]; p=0.0005), which was greater than that observed in group D. Conclusions Our findings demonstrate that the use of dexmedetomidine over propofol in elderly patients undergoing cardiac surgery is unlikely to improve QoR/post-operative QoL. Although the study was underpowered to detect secondary outcomes, the results suggest no reduction in delirium, time to extubation and hospital stay; but a potential decrease delayed neurocognitive recovery.