Acute Acoustic Trauma after Exposure to Assault Rifle Noise among Conscripts in the Finnish Defence Forces-A Population-Based Survey.

Conscripts are exposed to various sources of impulse noise despite hearing protection recommendations. The aim of this study was to investigate the frequency of acute acoustic trauma (AAT) among conscripts after exposure to assault rifle noise in the Finnish Defence Forces (FDF). This nationwide population-based cohort comprised all conscripts (>220,000) in the FDF during the years 1997-2003 and 2008-2010. We included those who claimed to have AAT symptoms from assault rifle noise during the study periods. During the investigated 10 years, 1617 conscripts (annual variation, 75-276) experienced a new hearing loss due to AAT. Altogether, 1456 (90%) of all AAT-induced hearing losses were caused by rifle-caliber weapons and 1304 (90%) of them when firing a blank cartridge. There was no clear diminishing trend in the annual numbers of AATs. In 1277 (88%) incidents, no hearing protector was used. Tinnitus was the most prominent symptom. Hearing losses after AAT were typically mild, but serious deficits also occurred. In conclusion, we found that 0.7-1.5% of the conscripts experienced an AAT during their service in the FDF. Most incidents occurred when firing a blank cartridge with a rifle-caliber weapon and with no hearing protector in use.

Military and leisure-time noise exposure and hearing thresholds of Finnish conscripts.

This study presents an evaluation of the total cumulative noise exposure of Finnish conscripts (N = 416) during military service. All of the conscripts underwent a hearing screening and filled out a noise exposure questionnaire at the beginning and end of their military service. Eighty-nine percent of the conscripts were exposed weekly to military noise of over 85 dBA during the service. Eighteen percent of the conscripts had already reached at the end of their military service a cumulative noise dose corresponding to noise exposure of 85 dB for 40 years. During military service, permanent hearing loss of > 20 dB in the frequency range of 0.5 to 8 kHz increased from 19 to 27% among the conscripts.

How bacteraemia is reviewed by medicines licensing authorities in Europe.

Bacteraemia has not been recognised as a therapeutic indication in Europe since the publication of the Note for Guidance on Evaluation of Medicinal Products for Treatment of Bacterial Infections in 1997 by the European Medicines Agency (EMEA). This standpoint is in sharp contrast to the labelling decisions taken by the US Food and Drug Administration (FDA). In Europe, a site-specific indication, such as treatment of complicated skin and soft tissue infections is considered to cover cases with bacteraemia, but not vice versa. Only cautionary information is presented in the labelling, e.g. if the number of bacteraemia cases in clinical trials has been low enough to be of concern or if the pharmacokinetic characteristics of the drug may not secure sufficient concentrations in blood. Primary bacteraemia is potentially a situation where the described regulatory paradigm may not apply, but this has yet to be tested. The European approach is likely to be increasingly challenged due to the increasing incidence of bloodstream infections, particularly due to resistant pathogens, and the associated high morbidity and mortality.

Estimated leisure-time noise exposure, hearing thresholds, and hearing symptoms of Finnish conscripts.

The aim of this study was to set up a statistical measure for determine the total cumulative noise exposure of Finnish conscripts (n = 1,054) as a result of leisure-time noise activities. All of the conscripts underwent hearing screening. The conscripts' time in noisy activities and their rating of the loudness and estimated noise levels of the activities were used as the predictors in the risk analysis. Self-reported hearing symptoms (i.e., tinnitus, pain in the ear) and hearing loss due to noise exposure were also inquired about. Twenty-seven percent of the conscripts had weekly noise exposure to > 85 dBA. Approximately 20% of the conscripts had >20 dB hearing loss in either ear in the frequency range of 0.5 to 8 kHz. The incidence of hearing symptoms seemed to correlate with an increased noise dose.

Noise attenuation and proper insertion of earplugs into ear canals.

OBJECTIVES: The study was done to determine whether the noise attenuation attained with the use of earplugs can be improved by teaching the proper insertion of earplugs to users. METHODS: Fifty-four randomly selected male subjects were divided into an untrained group (25 persons) and a trained group (29 persons). The trained group was given a lecture on earplug insertion and allowed to practise the insertion procedure, whereas the untrained group acted as controls. The untrained group received this training afterwards. The success of the training was measured by the MIRE (microphone in real ear) and REAT (real ear at threshold) methods, visual evaluation and an analysis of the properties of the subjects' ear canals. RESULTS: According to the MIRE method, the averaged A-weighted noise attenuation was 21 dB for the untrained group and 31 dB for the trained group. With the REAT method the attenuation at 1000 Hz was 24 dB for the untrained group and 30 dB for the trained group. The visual evaluation of the earplug fit was 1.9 for the untrained group and 2.6 for the trained group (scales 0-3). CONCLUSION: The results indicate that training in earplug insertion is important for good attenuation and for diminishing poor attenuation to a minimum.