Drug delivery as control task: improving performance in a common anesthetic task

To conceptualize delivery of anesthesia as a control task, similar to control tasks in nonmedical domains, and to evaluate how presentation of new information and feedback affects task performance.

In anesthesia, integrated monitors that show intravenous drug and effect-site concentrations in a patient currently do not exist. However, using real-time displays of intravenous anesthetic concentrations and effects could significantly enhance intraoperative clinical performance. Pharmacological models are available to estimate past, present, and future drug concentrations in the brain and to predict the drug's physiological effects. A display that integrates pharmacological models and visualizes drug concentrations was developed and tested to see if this drug display significantly improved clinical performance.

Thirty-three anesthesiologists with different levels of expertise administered anesthesia to simulated patients in a high-fidelity patient simulator. The experimental group used a drug display that visualized drug concentrations in real time, whereas the control group administered drugs without this information.

Anesthesiologists using the drug display achieved better hemodynamic control of the simulated patient than did the control group. Similarly, the drug display enabled anesthesiologists to wake up and reanimate the patient faster.

Visual feedback of drug concentrations leads to superior performance in the delivery of anesthesia. Drug delivery can be conceptualized within a control theoretical framework. Finally, the drug display has significant clinical potential to increase patient safety.

Clinical performance in delivering anesthesia depends on feedback. By providing this feedback, the drug display supports clinicians' ability to more precisely and safely administer anesthesia.