Through human factors engineering, closed claims databases, and research in simulation, we have learned a good deal about how humans work in our complex anesthesia environments. To keep our patients safe, we should apply our knowledge of human factors, cognitive load, and situational awareness to our workday. Here are some tips based on these concepts that we can apply to our own practice and teach others.

Cognitive load

Cognitive load theory describes the process of acquiring new information and converting it to working memory (Med Teach 2014;36:371-84).

  • Humans have limited working memory for acquiring new knowledge. We can generally only hold about seven facts in working memory.
  • Learning involves acquiring new information and moving this into long-term memory.
  • Once learned, we develop mental models called schema that are shortcuts when the memories are practiced.
  • Reducing cognitive load allows us to manage bottlenecks in working memory.
  • Cognitive load is increased with complexity and distractions and decreased with routine, protocols, and practice (schema development).

Situational awareness

Situational awareness describes the process in dynamic systems of perceiving, comprehending, and acting on information (Anesthesiology 2017;127:326-37).

  • Each step is fraught with the chance for error. Even an expert can have “inattentional blindness” in moments of stress.
  • The enemy of situational awareness is our own failings as humans; we are subject to stress, fatigue, temperature (think PPE), workload, case complexity, and new technology. We fail to see signs in patients or fail to act correctly when we encounter problems. Trainees are much more likely to be subject to these human factors at a time when they have fewer mental models and less expertise to fall back on (Anesth Analg 2015;121:1586-99).

Tips for using the concepts of cognitive load and situational awareness to improve patient safety:

  • Human factors research supports the use of standardization, checklists, timeouts, and cognitive aids to help us free up space in our working memory.
  • We can build failure-proof systems with forcing functions and EHR decision-support solutions to keep us safe without adding cognitive load. Trainees should be encouraged to develop routines such as standardizing medication and room set-up. Supervisors must assist trainees by decreasing distractions (including teaching) at busy times and monitoring stress (Anesthesiology 2018;128:44-54).
  • Situational awareness can be increased by planning ahead, anticipating problems, and instituting a post-case debrief to solidify good practices.

Understanding our human limitations and looking for ways to increase our cognitive abilities will help us and our trainees be more capable in the moment when we need to be mentally present. Our patients are counting on it.