Pilot study to determine the ability of health-care professionals to undertake drug dose calculations.

BACKGROUND: It is essential for health-care professionals to calculate drug doses accurately. Previous studies have demonstrated that many hospital doctors were unable to accurately convert dilutions (e.g. 1:1000) or percentages (e.g. percentage w/v) of drug concentrations into mass concentrations (e.g. mg/mL). AIMS: The aims of the present study were to evaluate the ability of health-care professionals to perform drug dose calculations accurately and to determine their preferred concentration convention when calculating drug doses. METHODS: A selection of nurses, medical students, house surgeons, registrars and pharmacists undertook a written survey to assess their ability to perform five drug dose calculations. Participants were also asked which concentration convention they preferred when calculating drug doses. The surveys were marked then analysed for health-care professionals as a whole and then by subgroup analysis to assess the performance of each health-care-professional group. RESULTS: Overall, less than 14% of the surveyed health-care professionals could answer all five questions correctly. Subgroup analysis revealed that health-care professionals' ability to calculate drug doses were ranked in the following order: registrars approximately equal to pharmacists > house surgeons > medical students >> nurses. Ninety per cent of health-care professionals preferred to calculate drug doses using the mass concentration convention. CONCLUSIONS: Overall, drug dose calculations were performed poorly. Mass concentration was clearly indicated as the preferred convention for calculating drug doses.

Excitotoxicity can be mediated through an interaction within the optic nerve; activation of cell body NMDA receptors is not required.

Axonal trauma leads to a series of pathologic events that can culminate in neuronal death. Although the precise mechanisms of retinal ganglion cell death after optic nerve crush in the rat model have not been elucidated, glutamate antagonists can protect retinal ganglion cells after optic nerve axotomy. We therefore explored whether a glutamate congener was toxic if applied directly within the optic nerve, or if toxicity depended upon an interaction at the cell body level. NMDA reduced retinal ganglion cell survival when applied directly into the rat optic nerve. Glutamate can be toxic if administered within the optic nerve; a direct effect at the cell body is not necessary. Future work will help to additionally unravel the steps by which axotomy induces excitotoxic damage to ganglion cells, and perhaps indicate protective interventions.

Death, injury and revival of chemically treated Bacillus subtilis spores.

The resistance of spores of Bacillus subtilis NCTC 10073 to glutaraldehyde, sodium hypochlorite and povidone-iodine was compared. Revival of treated spores was examined by use of defined germination media and conditions, protein denaturing agents, ultrasonics and heat. Revival, obtained after treatment with each of the three chemical agents, originated under different sets of conditions and was of two recognizably distinct types. The results, including the evidence of electron microscopy, are discussed in terms of chemical-spore reactivity and the implications on their use and suitability as chemical sterilizers.

Microbiology of the canine nasal cavities.

The anterior and superior regions of canine nares yielded two distinct microbial populations consisting of 25 microbial species. Streptococci predominated in the anterior nose; clostridia and staphylococci were also quite prevalent. At least two distinct microorgranisms were cultured from most anterior sites. In contrast, sterile conditions prevailed in the superior nasal regions of at least 50% of the ninety-two animals. Various Bacillus sp. were recovered from the remainder.