Impact of a Protocol Advocating Dexmedetomidine Over Propofol Sedation After Robotic-Assisted Direct Coronary Artery Bypass Surgery on Duration of Mechanical Ventilation and Patient Safety

BACKGROUND: Controversy remains whether propofol or dexmedetomidine is the preferred sedative following cardiac surgery. Dexmedetomidine may offer advantages over propofol among patients undergoing robotic-assisted, minimally invasive, direct coronary artery bypass (MIDCAB) surgery given the rapidity with which this population is usually extubated after surgery. OBJECTIVE: To measure the impact of a surgery protocol advocating use of dexmedetomidine rather than propofol after MIDCAB surgery on discontinuation of mechanical ventilation and patient safety. METHODS: The records on consecutive adults undergoing MIDCAB surgery who received postoperative sedation with propofol or dexmedetomidine at a 508-bed academic medical center were analyzed before and after implementation of a post-MIDCAB surgery protocol advocating dexmedetomidine use. RESULTS: Seventy-three propofol patients were compared with 53 dexmedetomidine patients. The groups were similar, except propofol patients were older (p = 0.002) and more likely to have underlying heart failure that was either moderate or severe (New York Heart Association class III or IV) (p = 0.0001). Time (median [interquartile range]) to extubation (hours) was shorter in the dexmedetomidine group (5.0 [3.6-7.0] vs 9.8 [5.0-16.3]; p = 0.0001). A Cox proportional hazards model revealed that patient age (p = 0.001) and duration of surgery (p = 0.003) influenced time to extubation between the dexmedetomidine and propofol groups but the presence of moderate or severe heart failure (p = 0.438), the number of coronary vessels operated on (p = 0.130), use of an opioid (p = 0.791), or the total dose of morphine administered (p = 0.215) did not. During sedation administration, more propofol-treated patients experienced 1 or more episodes of hypotension (systolic blood pressure ≤80 mm Hg, 11.6% vs 0%; p = 0.02), tachycardia (heart rate ≥120 beats/min, 8.6% vs 0%; p = 0.04), and unarousability (Sedation Agitation Scale score ≤2, 30.0% vs 9.4%; p = 0.03). CONCLUSIONS: Use of a protocol promoting dexmedetomidine, rather than propofol sedation, after MIDCAB surgery facilitates faster discontinuation of mechanical ventilation and is associated with greater hemodynamic stability and arousability.