Biomedical subjects

O W Herndon

Publications and source records attributed to O W Herndon.

2 recordsLinked to original sources

PubMed1997

The effect of electronic record keeping and transesophageal echocardiography on task distribution, workload, and vigilance during cardiac anesthesia.

BACKGROUND: Electronic anesthesia record keeping (EARK) systems increasingly are used in the operating room, but studies have only recently begun to investigate their effect on anesthesia task performance. Teak analysis, workload assessment, and vigilance assessment techniques were used to study senior residents providing anesthesia for coronary artery bypass graft (CABG) procedures. The impact on anesthesia residents' workload of the routine use of transesophageal echocardiography (TEE) also was examined. METHODS: Before each case, the record keeping system was randomly selected as either electronic (Distek ARKIVE; EARK) or traditional manual recording (MAN). Twenty CABG procedures (10 EARK and 10 MAN) were examined, with observation commencing with anesthetic induction and terminating on initiation of cardiopulmonary bypass. The activities of each resident, divided into 32 task categories (e.g., "laryngoscopy," "observe monitors," etc.), were recorded by a trained observer using a computer. The response latency to a randomly activated alarm light was used as a measure of vigilance ("vigilance latency"). Workload was rated by subject and observer at random 10- to 15-min intervals throughout the case. Data analysis included calculation of workload density (number of tasks/min multiplied by task-specific workload values) and task-links (relationship between sequential tasks). RESULTS: The two groups had a similar distribution of tasks before intubation. In only 4 of the 20 cases studied did any manual record keeping occur before intubation. After intubation, the EARK group spent less time record keeping and using the TEE but more time observing the monitors and conversing with the attending physician than the MAN group did. All subjects reported significantly higher workload scores before intubation compared with after intubation. Similarly, vigilance latency was greater before intubation compared with after intubation (57 vs. 31 s; P < 0.001). There were no significant differences between the two record keeping groups in subjective workload scores, workload density, or vigilance latency. During TEE use, vigilance latency was significantly longer, and workload density was greater than during other monitoring or recording tasks. CONCLUSIONS: This study provides an objective description of the task distribution and workload during the administration of anesthesia for cardiac surgery. Under the conditions of this study. EARK use modestly decreased the time spent record keeping during the postintubation prebypass period. However, there was no effect of EARK either on vigilance or several measures of workload. TEE use was associated with increased workload and possibly decreased vigilance.

Anesthesiology↗

PubMed1994

An objective methodology for task analysis and workload assessment in anesthesia providers.

BACKGROUND: Administering anesthesia is a complex task in which either human or equipment failure can have disastrous consequences. An improved understanding of the nature of the anesthesiologist's job could provide a more rational basis for improvements in provider training as well as the design of anesthesia equipment. The objective of this study was to develop a set of techniques to evaluate anesthesiologist performance and to determine what information could be obtained from performing real-time task assessment and workload analysis tests in the operating room. METHODS: The methodology used included time-motion analysis, secondary task probing, and subjective workload assessment. The time-motion data was subjected to subsequent analysis to generate quantitative measures such as task duration (time spent focused on an individual task) and task density (the number of tasks initiated per minute). The latency of response to a "vigilance light" was used as a secondary task probe. Finally, both the observer and the subjects themselves scored workload at 10-15-min intervals throughout the case. Two groups of anesthesia providers performing general endotracheal anesthesia for simple ambulatory surgical cases (1-4 h duration) were examined using this methodology. In the first group, 3rd-yr anesthesia residents and experienced certified registered nurse anesthetists (n = 11) performed cases under limited supervision by an attending anesthesiologist. In the second group, novice residents in their first 8 weeks of training (n = 11) performed similar cases under nearly constant attending supervision. RESULTS: The two groups seemed to manifest different patterns of task behavior, task density, subjective workload, and latency of response to the vigilance task. Response latency to the vigilance task increased at times of increased workload (e.g., during induction of anesthesia). The experienced (less supervised) providers spent significant amounts of time observing the monitors and the surgical field, whereas the novice subjects spent more time conversing with the supervising attending. Despite performing fewer tasks per minute (lower task densities), the novice subjects exhibited longer latencies of response to the vigilance light and increased subjective workload. Novice subjects also had longer task duration values. For example, postintubation, novices focused on their monitors for an average of twice as long as did experienced subjects (13 +/- 2 vs. 7 +/- 1 s) before moving on to another task. CONCLUSIONS: These techniques permitted an objective description of task characteristics, workload, and vigilance in anesthesia personnel under actual work conditions. This methodology could aid in understanding the factors that affect anesthesiologists' performance and may prove useful in assessing the progress of training.

Anesthesiology↗