At-a-Glance Monitoring: Covert Observations of Anesthesiologists in the Operating Room

Department of Anesthesia, British Columbia Children's Hospital, Vancouver, British Columbia, Canada.
Anesthesia and analgesia (Impact Factor: 3.47). 09/2010; 111(3):653-8. DOI: 10.1213/ANE.0b013e3181e627d4
Source: PubMed


Patient monitoring displays are designed to improve patient safety, and yet little is known about how anesthesiologists interact with these displays. Previous studies of clinician behavior used an observer in the operating room, which may have altered behavior. We describe a covert observation technique to determine how often and for how long anesthesiologists actually look at the monitoring display during different segments of the maintenance phase of anesthesia, and to determine whether this changed with more than 1 anesthesia provider or during concomitant activities such as reading.
Five staff anesthesiologists, 2 anesthesia fellows, 3 anesthesia residents, and 2 medical students were covertly videotaped across 10 dual anesthesia provider cases and 10 solo cases. Videotapes were later segmented (5 minutes postinduction [early maintenance], mid-maintenance, and immediately before the drapes came down [late maintenance]) and coded for looking behavior at the patient monitor, anesthesia chart, and other reading material.
Anesthesiologists looked at the monitor in 1- to 2-second glances, performed frequently throughout the 3 segments of maintenance anesthesia. Overall, the patient monitor was looked at only 5 of the analyzed time, which is less than has previously been reported. Monitoring behavior was constant across the segments of maintenance anesthesia and was not significantly affected by the number of anesthesia providers or role (trainee vs. senior). In contrast, charting behavior and other reading material viewing changed significantly over the analyzed segments of maintenance anesthesia.
The presence of "at-a-glance monitoring" has implications for the design of patient monitoring displays. Displays should be developed to optimize the information obtained from brief glances at the monitor.

9 Reads
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Anesthesiologists monitor their patients' vital signs vigilantly during surgical procedures in the operating room. The vital signs are typically presented on a graphical display mounted on the anesthesia workstation, but the display is often located in an awkward position and out of view of the anesthesiologist, especially when they are performing procedures. One solution to this problem is the use of head-mounted displays. Head-mounted displays (HMDs) are head-worn display devices that project a computer-generated information display over the user's field of view, similar to the head-up displays commonly used in aviation. Anesthesiologists using an HMD would be able to see the vital signs at all times in the operating room – no matter where they are, or where they are looking. Despite their technological and methodological limitations, prior investigations of HMDs in anesthesia have demonstrated benefits such as improved event detection and a reduced need to look towards the anesthesia workstation. In other domains, however, researchers have found cognitive and perceptual issues associated with the use of head-up displays that have not been investigated with HMDs in anesthesia. Head-up displays can worsen the tendency for users to miss salient, safety-critical unexpected events in their visual field (the sustained inattentional blindness phenomenon), and this has been replicated with HMDs in laboratory settings. Head-up displays can also cause perceptual problems such as involuntary eye mis-accommodation, resulting in decreased visual acuity and slower event detection. This thesis reports a series of three experiments that was conducted to determine whether the advantages and disadvantages of head-up displays in aviation would also apply to HMDs in anesthesia. Anesthesiologists at the Royal Adelaide Hospital provided anesthesia in simulated and clinical operating room environments while using either a standard patient monitoring display, or the standard display plus a Microvision Nomad ND2000 HMD. The HMD presented a real-time display of the patient's vital signs that was visible to the anesthesiologist at all times. All of the simulator scenarios and surgical cases were video recorded for offline coding and analysis. In Experiment 1, twelve anesthesiologists provided anesthesia in a simulated operating room environment using a METI Emergency Care Simulator. The goals of the study were to determine (1) whether HMDs would help anesthesiologists detect unexpected events faster during normal anesthesia, and (2) whether the HMD focal depth would affect their performance. The results showed that there was no significant difference in the number of events detected, nor event detection times, between the display conditions and focal depths. When using the HMD, however, participants spent a smaller proportion of time looking towards the anesthesia workstation, and a greater proportion of time looking towards the patient and surgical field. In Experiment 2, twelve anesthesiologists performed a simulated prolonged fiber-optic intubation by navigating a Replicant Dexter Endoscopic Dexterity Trainer maze using a fiber-optic scope while monitoring patient vital signs. The goal of the study was to determine whether HMDs would help anesthesiologists detect patient events faster when they are physical and operationally constrained. The results showed that participants detected two of four events faster when using the HMD compared to standard monitoring, but another waveform event was detected more slowly with the HMD. The slower event detection could not be explained by inattentional blindness alone, but by a combination of inattentional blindness, perceptual differences between events, and overconfidence. In conditions with the HMD, participants again spent less time looking towards the workstation and more time looking towards the patient area, as in Experiment 1. In Experiment 3, six anesthesiologists provided anesthesia for human patients undergoing elective rigid cystoscopy surgical procedures. The goal of the study was to determine whether the reduced need for anesthesiologists using HMDs to look at the monitors would translate from the simulated operating rooms in Experiments 1 and 2 to the clinical environment. The results showed that in conditions with the HMD, participants spent less time looking towards the workstation, and more towards the patient and surgical field, as in the prior experiments. The findings from the three experiments confirm that HMDs can help anesthesiologists redirect their attention away from the anesthesia workstation and towards the patient and surgical field. However, the benefits of monitoring with HMDs were more pronounced during constrained contexts, where the anesthesiologist could also detect patient events more quickly with the HMD, than during routine monitoring. Although there was no direct evidence of inattentional blindness (as per the aviation studies of head-up displays), improved display design techniques may be required to mitigate the slower detection of waveform changes on the HMD. The technologies needed to conduct the above experiments were not commercially available therefore several innovative solutions were developed. A wireless HMD monitoring system was built using off-the-shelf components and interfaced with a patient simulator (Experiments 1 and 2) and clinical patient monitors (Experiment 3) to display patient vital signs in real-time. The simulator was extended to provide capnography, airway gas monitoring, and blood pressure cycling. Finally, an audiovisual recording system was developed to record video data in the operating room, and a custom software tool was written for coding the video data. In future work, more research is needed to investigate the benefits that HMDs can provide during specific situations, such as crisis management or providing anesthesia to unstable patients; designing effective information displays for HMDs; and integrating the HMD with other display modalities such as auditory and vibrotactile displays.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present a technique for self-localisation of a mobile robot in structured office environments using a monocular on-board camera only. Most state of the art approaches to map building and localisation in mobile robotics are probabilistic. The majority depends on accurate proximity sensors such as laser range finders or sonar sensors. As an alternative, we have developed a probabilistic sensor model for robot vision. By matching straight-line segments extracted from the camera image with a geometrical model of the environment, it computes a probability that a given image has been obtained at a certain place in the robot's operating environment. The use of straight-line segments as features provides both computational efficiency and robustness with respect to noise and inaccuracies of the map. We have compared the performance of the sensor model with a traditional one for a laser range finder in the common framework of Monte-Carlo localisation. Given the results on robustness and accuracy of position estimation, our localisation technique is applicable for mobile robots in structured indoor environments that do not have laser sensors. Moreover, the model is appropriate for sensor fusion and object recognition.
    Intelligent Robots and Systems, 2004. (IROS 2004). Proceedings. 2004 IEEE/RSJ International Conference on; 07/2004
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This article summarizes the current state of technology as it pertains to quality in the operating room, ties the current state back to its evolutionary pathway to understand how the current capabilities and their limitations came to pass, and elucidates how the overlay of information technology (IT) as a wrapper around current monitoring and device technology provides a significant advance in the ability of anesthesiologists to use technology to improve quality along many axes. The authors posit that IT will enable all the information about patients, perioperative systems, system capacity, and readiness to follow a development trajectory of increasing usefulness.
    Anesthesiology Clinics 03/2011; 29(1):29-55. DOI:10.1016/j.anclin.2010.11.006
Show more