Closed-Loop Anesthesia: Not Ready for Takeoff

    loading  Checking for direct PDF access through Ovid


The editorial1 accompanying 2 recent meta-analyses2,3 in Anesthesia & Analgesia argues that closed-loop feedback anesthesia delivery systems are imminent in American medicine due to “less overshoot and undershoot, faster recovery from anesthesia, and lower anesthetic doses.” The authors link increased consistency with patient safety and note the use of these systems will change the role of our specialty.
First, we are not convinced these studies show meaningfully improved performance. While 1.62 minutes of faster recovery, induction doses of 0.37 mg/kg less propofol, and bispectral index values 5.86 points lower may all be statistically significant, are these clinically significant?2 The authors of the meta-analyses themselves note these “subtle advantage(s) … may not be evident to practicing anesthesiologists.”2 Nevertheless, subtle advantages are only important if they show direct correlation to improved patient outcomes. Regardless whether better performances or outcomes can be found, we think the major issue is not technological advancement but how to manage the risk associated with that technology.
The editorial notes that air carriers use autopilot on takeoff and landing. Discussing this statement with a Boeing 777 instructor from a major carrier, he noted that in fact the Federal Aviation Administration (FAA) does not allow the use of autopilots on takeoff until a certain minimum altitude is first obtained. This varies by the specific plane. For his plane, this minimum is 200 feet above ground level, a number obtained by tests that showed a human pilot could catch an autopilot malfunction with a 100-foot loss of altitude. To create a safe margin, the FAA then doubled this to provide the requirement in the Flight Manual for the Boeing 777.
The FAA has an approach to assess the risk profile of the technology and then implement appropriate usage policies. Similarly, are we delaying the implementation of this technology by seeking to show it is “better” when actually we should be discussing the risks with which we—as professionals and patients—are comfortable?
Although studies showing the efficacy of closed-loop devices are important, the pertinent questions seem to be primarily about risk.
    loading  Loading Related Articles