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Original article
Emergency department noise: mental activation or mental stress? Lindy-Lee Folscher,1 Lara Nicole Goldstein,1 Mike Wells,1 David Rees2 1
Division of Emergency Medicine, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Gauteng, South Africa 2 Occupational Medicine, National Institute for Occupational Health, National Health Laboratory Service and School of Public Health University of the Witwatersrand, Constitution Hill, Gauteng, South Africa Correspondence to Dr Lindy-Lee Folscher, Division of Emergency Medicine, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Gauteng, South Africa, P.O. Box 1889, Heidelberg 1438, South Africa; [email protected] Received 25 February 2014 Revised 11 June 2014 Accepted 17 June 2014 Published Online First 7 July 2014
ABSTRACT Background Healthcare professionals working in emergency medicine are often exposed to noisy environments. We determined if there is any difference in cognitive task performance required for clinical decision-making of healthcare professionals in a quiet compared with noisy environment and to assess the subjective experience of participants with regard to performance in a noisy environment. Methods This was a prospective cross-over study conducted at three academic hospitals in Johannesburg, South Africa. 41 doctors involved in the emergency management of patients were administered six matched and prevalidated medical questions over a 30-min period. Each doctor completed half of the questions with exposure to ambient noise (range 40–52 dB(A)) and the other half with exposure to pre-recorded background emergency department noise at 80–85 dB(A). The questions were completed in alternating quiet and noise: half of the physicians answered the odd questions in noise and half answered even numbered questions in noise. Each question was scored out of 10 and the time taken to complete each question was recorded. Results Overall median test scores in quiet and noise were 18.5/30 and 20/30 ( p=0.2), respectively; time for test completion was longer in quiet (836 s in quiet and 819 s in noise ( p=0.006)). While there was no statistically significant difference in task performance, 65% of the doctors found the noise distracting with 88% experiencing varying degrees of stress. Conclusions Performance of mental tasks is maintained during noise exposure but noise exposure is associated with significant degrees of self-reported distress.
INTRODUCTION
To cite: Folscher L-L, Goldstein LN, Wells M, et al. Emerg Med J 2015;32: 468–473. 468
Emergency medicine practice requires rapid integration of clinical information and rapid decisionmaking processes which demand concentration, attention, mental efficacy, short-term and working memory and problem-solving ability. Decisions are often critical, which place strain on the mental capabilities of the professional. The environments emergency professionals work in are often far from ideal, and yet these professionals are expected to function optimally. The emergency department is one of the noisiest places within the hospital, yet here critically ill patients need to be managed with speed and precision.1 2 Tijunelis et al3 measured the noise levels in an emergency department over a period of 8 h and found an average of 52.9 dB(A) with peak levels of 94–117 dB occurring every minute. It is therefore important to assess the effect of loud noise on healthcare workers’ clinical problem-solving ability.
Key messages What is already known on this subject ▸ Chronic noise exposure has been shown to be detrimental to cognitive functioning. ▸ Studies on the acute noise exposure have rendered variable results with some studies demonstrating improved cognitive performance and others impaired performance. ▸ The acute effect of emergency department noise on doctors’ ability to perform clinical decision-making tasks was unknown. What this study adds ▸ During this study, the performance of mental tasks were maintained during intermittent noise exposure at 85 dB(A) with associated faster performance. ▸ However, noise exposure was associated with significant degrees of self-reported distress.
Noise exposure has an effect on communication, hearing, sleep, mental state, task performance, cardiovascular function, annoyance levels and social behaviour.4 5 Studies on the effects of chronic noise exposure on various aspects of human functioning and physiology demonstrate impaired cognitive performance.4–8 Many of these effects may also be expected following noise exposure in the acute setting. Noise exposure has both positive and negative effects on task performance with negative effects more likely with complex tasks and less likely in the initial stages of exposure.6 9 When improvement in performance is demonstrated, it is more likely to occur with simple tasks since these tasks are likely to elicit boredom; noise, therefore, acts as a stimulus to increase arousal and attention.9 Steady noise at low or moderate levels (
Original article
Emergency department noise: mental activation or mental stress? Lindy-Lee Folscher,1 Lara Nicole Goldstein,1 Mike Wells,1 David Rees2 1
Division of Emergency Medicine, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Gauteng, South Africa 2 Occupational Medicine, National Institute for Occupational Health, National Health Laboratory Service and School of Public Health University of the Witwatersrand, Constitution Hill, Gauteng, South Africa Correspondence to Dr Lindy-Lee Folscher, Division of Emergency Medicine, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Gauteng, South Africa, P.O. Box 1889, Heidelberg 1438, South Africa; [email protected] Received 25 February 2014 Revised 11 June 2014 Accepted 17 June 2014 Published Online First 7 July 2014
ABSTRACT Background Healthcare professionals working in emergency medicine are often exposed to noisy environments. We determined if there is any difference in cognitive task performance required for clinical decision-making of healthcare professionals in a quiet compared with noisy environment and to assess the subjective experience of participants with regard to performance in a noisy environment. Methods This was a prospective cross-over study conducted at three academic hospitals in Johannesburg, South Africa. 41 doctors involved in the emergency management of patients were administered six matched and prevalidated medical questions over a 30-min period. Each doctor completed half of the questions with exposure to ambient noise (range 40–52 dB(A)) and the other half with exposure to pre-recorded background emergency department noise at 80–85 dB(A). The questions were completed in alternating quiet and noise: half of the physicians answered the odd questions in noise and half answered even numbered questions in noise. Each question was scored out of 10 and the time taken to complete each question was recorded. Results Overall median test scores in quiet and noise were 18.5/30 and 20/30 ( p=0.2), respectively; time for test completion was longer in quiet (836 s in quiet and 819 s in noise ( p=0.006)). While there was no statistically significant difference in task performance, 65% of the doctors found the noise distracting with 88% experiencing varying degrees of stress. Conclusions Performance of mental tasks is maintained during noise exposure but noise exposure is associated with significant degrees of self-reported distress.
INTRODUCTION
To cite: Folscher L-L, Goldstein LN, Wells M, et al. Emerg Med J 2015;32: 468–473. 468
Emergency medicine practice requires rapid integration of clinical information and rapid decisionmaking processes which demand concentration, attention, mental efficacy, short-term and working memory and problem-solving ability. Decisions are often critical, which place strain on the mental capabilities of the professional. The environments emergency professionals work in are often far from ideal, and yet these professionals are expected to function optimally. The emergency department is one of the noisiest places within the hospital, yet here critically ill patients need to be managed with speed and precision.1 2 Tijunelis et al3 measured the noise levels in an emergency department over a period of 8 h and found an average of 52.9 dB(A) with peak levels of 94–117 dB occurring every minute. It is therefore important to assess the effect of loud noise on healthcare workers’ clinical problem-solving ability.
Key messages What is already known on this subject ▸ Chronic noise exposure has been shown to be detrimental to cognitive functioning. ▸ Studies on the acute noise exposure have rendered variable results with some studies demonstrating improved cognitive performance and others impaired performance. ▸ The acute effect of emergency department noise on doctors’ ability to perform clinical decision-making tasks was unknown. What this study adds ▸ During this study, the performance of mental tasks were maintained during intermittent noise exposure at 85 dB(A) with associated faster performance. ▸ However, noise exposure was associated with significant degrees of self-reported distress.
Noise exposure has an effect on communication, hearing, sleep, mental state, task performance, cardiovascular function, annoyance levels and social behaviour.4 5 Studies on the effects of chronic noise exposure on various aspects of human functioning and physiology demonstrate impaired cognitive performance.4–8 Many of these effects may also be expected following noise exposure in the acute setting. Noise exposure has both positive and negative effects on task performance with negative effects more likely with complex tasks and less likely in the initial stages of exposure.6 9 When improvement in performance is demonstrated, it is more likely to occur with simple tasks since these tasks are likely to elicit boredom; noise, therefore, acts as a stimulus to increase arousal and attention.9 Steady noise at low or moderate levels (
