Tetris and physician's performance state

February to April, 1995 (weeks 95/5-16), which corresponded to the period of increased influenza activity in the UK during the last season, a total of 293 isolates of influenza virus were reported by Public Health Laboratory Service (PHLS) and National Health Service hospital laboratories to the PHLS Communicable Disease Surveillance Centre in London. During the same period a total of 47 isolates of influenza virus were received from GPs participating in a PHLS virological surveillance scheme for influenza-like illness.’ 96% of the hospital laboratory derived isolates were of influenza B, which was similar to the 98% of influenza B viruses found in those isolates derived from the sentinel GP surveillance. It seems reasonable to assume that patients in hospital, from whom influenza virus has been isolated, will generally be more ill than such patients in the community. It is also recognised that influenza A generally, although not in every individual, causes a more severe illness than influenza B infection. Nevertheless, other factors should be considered before concluding that hospital laboratory-based surveillance cannot provide a representative picture of the influenza viruses circulating in the community. First, although virological laboratories in this country are almost exclusively located within hospitals, a large proportion of the isolates examined in these laboratories, and we suspect in the network of diagnostic virological laboratories of municipal health services and hospitals in the Netherlands, are derived from primary care. Second, several other factors could have a major effect on the observed distribution of isolates detected by a surveillance system, including the definition of influenza-like illness used for surveillance, the age distribution of patients examined, and the geographical representativeness of the sampling. Influenza vaccine coverage might theoretically also have an influence in some age groups, but the coverage would probably have to be very substantial to have any noticeable effect. We conclude that hospital laboratory-based surveillance will continue to provide valuable information on the occurrence of influenza virus in the community, albeit complemented by virological data derived from GP sentinel surveillance schemes. *John M Watson, Daniel Dedman, Carol Maria Zambon, Morag C Timbury

Dedman DJ, Joseph CA, Chakraverty P, Fleming DM, Watson JM. Influenza surveillance, England and Wales: October 1993 to June 1994. Comm Dis Rep 1994; 4: R164-68.

Tetris and

physician’s performance

study population consisted of six otherwise healthy physicians (5 men, 1 woman, median age 31, range 26-40 years). Mean basic scores for three assays were determined at duty entry at 0800 h when the doctors were likely to be at their optimum physical and mental performance state. Three routine control games had to be played after rounds at 1200, 1600, 2000 h and 0000 h. Stress values

were

the successful management of common ICU-problemssuch as cardiopulmonary resuscitation and treatment of haemodynamic and respiratory instabilities-and after lunch (if there was time for lunch). According to the interindividual difference in Tetris skill values-which were not related to gender and ICU experience, but mainly determined by age, previous Tetris experience and absence of other interestswere expressed as percentage of basic high score levels. Paired t-test was used for statistical evaluation. A slight numerical rise of scores (mean 5-6 [SD 30]%, p=not significant) was recorded between 0800 and 1200 h, but afterwards an exponential decline of achievable scores occurred in all staff members, apart from the head of the department. Differences between baseline and 0000 h were significant (mean 38-4 [19-1]%, p<0.01), indicating a timedependent alteration of physician’s performance state. However, lowest levels occurred after lunch, probably attributable to hyperfusion of the gut. Notably, other stress scores increased greatly after the management of common ICU problems, indicating enhanced physician’s limbic system perfusion and endorphine release. SPECT-analysis of this phenomenon is under investigation and will be published elsewhere. We conclude that Tetris is a rapid, easily available, objective, and non-invasive method for the determination of physicians’ performance state. A significant decline in scores should lead to immediate recreation, and food intake should be kept to a minimum when on call. *K Laczika, T M Frass

Staudinger,

G J Locker, S

Knapp, H Burgmann,

Department of Internal Medicine I, Intensive Care Unit, University of Vienna, A1090 Vienna, Austria

Prevention of relapses in systemic lupus erythematosus-In this paper by Bootsma et al (June 24, p 1595), the fifth sentence of the second paragraph of the summary should have read "Although rises in antidsDNA in the prednisone group were treated with additional prednisone, the cumulative oral doses of prednisone in the two groups did not differ significantly (p=0068)".

Accuracy of clinical assessment of deep vein thrombosis-In this article by Wells et al (May 27, p 1326), table 1 should have read:

state

SiR-Tetris (Sphere Inc, Elorg, Microsoft, USA) developed by Pazhitnov and Gerasimov in 1987 and

was

has been distributed worldwide since 1990. It has become an invaluable way to relax during night duty on the intensive care unit (ICU). Tetris high scores are decisively influenced severe pressure of work, and stress. We were interested in an intraindividual high score time course during long and stressful duty on the ICU.

by fatigue,

516

obtained after

DEPARTMENT OF ERROR

Joseph,

*PHLS Communicable Disease Surveillance Centre, London NW9 5EQ, UK; and PHLS Central Public Health Laboratory, Colindale

1

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Checklist

History

of recent trauma

(%60 days)

to the

symptomatic leg