Clinical practice and the UK Human Rights Act 1998: protecting individual rights in the interest of the wider community.

Health professionals have expressed concern that the UK Human Rights Act 1988, which came into force in 2000, may threaten their autonomy in clinical practice/decision-making and resource allocation by health authorities. Although healthcare-related cases have so far been slow to emerge under the Act, it seems clear that in clinical practice the transition from duty to legal obligation will involve a degree of change for health professionals, in attitude if not in behaviour. With regard to resource allocation, it appears that the UK courts are likely to consider challenges to health authorities' decisions in a way that takes into account the need to set priorities, so long as these decisions do not discriminate unfairly and can be shown to have been made in the best interest of the wider community.

Auditory evoked response test strategies to reduce cost and increase efficiency: the postauricular muscle response revisited.

We describe a number of techniques in auditory evoked response (AER) testing for hearing loss which should decrease its cost and increase its efficiency, making its use in infant hearing screening more viable. We demonstrate the use of bit-stream averaging of the electrical signals from the head as a cheap alternative to analogue averaging and show that the average waveforms obtained are similar with both techniques. We demonstrate how the postauricular muscle response (PAMR) can be potentiated by lateral rotation of the eyes and argue that uncontrolled eye movements in previous studies have led to an unfounded belief that the PAMR is not stable. When eye rotation is used to potentiate the PAMR, the response becomes very stable and so large in most subjects that it is clearly visible in the raw traces. We also demonstrate that when the PAMR is potentiated by eye rotation, stable PAMR waveforms can be reliably obtained with tone bursts with frequencies up to and above 8 kHz and with sound levels within 30 dB of the subjective detection threshold. As a result the PAMR can be used to rapidly determine an objective audiogram in most subjects within minutes. Finally, we demonstrate a correlation technique for detecting the PAMR without waveform averaging and the need for an expensive computer. We are sure that a combination of these techniques can be used to increase the efficiency of AER screening for infant deafness and lower its cost dramatically.

Comparative effects of inhaled silica or synthetic graphite dusts on rat alveolar cells.

Alterations in population profiles, morphology, and phagocytic activity of lung cells following in vivo exposure of Fischer 344 rats to a single dose of silica, were compared to similar changes following exposure to synthetic graphite. The effect of silica exposure on alveolar macrophage mycocidal activity was also measured. Acute exposure by inhalation to 100 mg/m3 silica dust produced persistent pulmonary inflammation, as well as long-term changes in pulmonary alveolar macrophages (AM) typical of macrophage activation. Both particles were steadily cleared from the lungs; AM from the silica study, as well as from the 100 and 500 mg/m3 graphite studies, contained ingested particles throughout the entire 3 month experimental period. Lavaged pulmonary cells showed no reduction in viability as a result of exposure to either of the dusts. After silica inhalation, the following changes were observed constantly in bronchopulmonary lavage cell samples: increased numbers of polymorphonuclear leukocytes (PMN), hypersegmented PMN, binucleated AM, increased AM phagocytic indices and capacities, and increased mycocidal activity. Following inhalation of 1-100 mg/m3 synthetic graphite the above-mentioned effects were not seen. Exposure to 500 mg/m3 graphite produced transient inflammation and AM activation for about 24-48 hr.

Test for decreased serotonin/tryptophan metabolite ratios in abstinent alcoholics.

A segment of the population has a defect in the metabolism of tryptophan that causes a lowered concentration of serotonin in the central nervous system and indicates a predisposition towards chronic alcoholism. The metabolic defect in tryptophan metabolism is in the pathway between tryptophan and 5-hydroxyindoleacetic acid (5-HIAA) but not in the other pathways of tryptophan metabolism. A test using HPLC with amperometric detection was developed to detect the presence of an impaired serotonin metabolic pathway and therefore indicate a predisposition towards chronic alcoholism. The test used a ratio between 5-HIAA and two metabolites (indoleacetic acid and anthranilic acid) from the other pathways of tryptophan metabolism to indicate the presence or absence of an impaired serotonin metabolic pathway while correcting for variations in the concentration of urine.

Comparative inhalation hazards of aluminum and brass powders using bronchopulmonary lavage as an indicator of lung damage.

Bronchopulmonary lavage has been used as a rapid screening test for acute lung injury from many pneumotoxic chemicals. We demonstrated the efficacy of lavage fluid analysis for detection of acute pulmonary damage from inhaled metal dusts. Groups of male, Fischer 344 rats were exposed 4 h to one of five dosage levels of either brass (200, 100, 50, 10, 1 mg m-3) or aluminum (1000, 200, 100, 50, 10 mg m-3). At 24 h, 14 days and 3 months post-exposure (PE), rats were evaluated for physiological and histological alterations to correlate with enzymatic and cytological profiles of lavage fluid. At 24 h PE, there were dose-related increases in lactate dehydrogenase and protein in lavage fluid of the brass exposed rats, acute inflammatory response in terminal airways, increases in macrophages and neutrophils, and increased pulmonary resistance. All reactions were resolved by 14 days PE. In contrast, aluminum powder produced no alteration in pulmonary function, but elicited persistent changes in enzymatic and cytological lavage fluid parameters with multifocal microgranulomas in lungs and hilar lymph nodes. Bronchopulmonary lavage analysis was useful as an indicator of inhalation hazards of brass and aluminum powders.