The impact of electronic decision support and electronic remote blood issue on transfusion practice.

OBJECTIVES: To assess the impact on transfusion practice of a two-stage electronic intervention: the introduction of a decision support system (DSS) followed by the addition of electronic remote blood issue (ERBI). BACKGROUND: With increasing evidence to show the benefit of restrictive transfusion policies, it is important to ascertain which interventions can increase clinician compliance with their implementation. A DSS provides patient-specific recommendations to clinicians. ERBI reduces delays in acquiring blood and may alter the transfusion behaviour of clinicians. METHODS: All electronically requested blood transfusions administered outside of surgical theatres or recovery were identified in an orthopaedic hospital. These were divided into three time periods corresponding to pre-intervention, the successive introduction of DSS alone and DSS with ERBI. Pre- and post-transfusion haemoglobin (Hb) concentration levels, and the number of units ordered and transfused were recorded. RESULTS: A total of 204 transfusions for 92 patients were assessed; 38 of 85 (45%) transfusions in the first time period were compliant. This did not significantly change after introduction of the DSS, but with DSS and ERBI together significantly increased to 39 of 60 (65%) (P < 0·05). Mean pre-transfusion Hb reduced from 8·24 g dl(-1) in the first time period to 7·67 g dl(-1) in the third (P < 0·0001). There was no significant change in overall blood usage, although ERBI significantly reduced the amount of unused blood orders from 70 to 25%. CONCLUSION: Electronic DSS was not sufficient to change practice in the form implemented in this study. ERBI can contribute to significant improvements in blood usage as well as the efficiency of blood provision.

Particle-size dependent effects in the Balb/c murine model of inhalational melioidosis.

Deposition of Burkholderia pseudomallei within either the lungs or nasal passages of the Balb/c murine model resulted in different infection kinetics. The infection resulting from the inhalation of B. pseudomallei within a 12 µm particle aerosol was prolonged compared to a 1 µm particle aerosol with a mean time-to-death (MTD) of 174.7 ± 14.9 h and 73.8 ± 11.3 h, respectively. Inhalation of B. pseudomallei within 1 µm or 12 µm particle aerosols resulted in a median lethal dose (MLD) of 4 and 12 cfu, respectively. The 12 µm particle inhalational infection was characterized by a marked involvement of the nasal mucosa and extension of bacterial colonization and inflammatory lesions from the olfactory epithelium through the olfactory nerves (or tracts) to the olfactory bulb (100%), culminating in abscessation of the brain (33%). Initial involvement of the upper respiratory tract lymphoid tissues (nasal-associated lymphoid tissue (NALT) and cervical lymph nodes) was observed in both the 1 and 12 µm particle inhalational infections (80-85%). Necrotising alveolitis and bronchiolitis were evident in both inhalational infections, however, lung pathology was greater after inhalation of the 1 µm particle aerosol with pronounced involvement of the mediastinal lymph node (50%). Terminal disease was characterized by bacteraemia in both inhalational infections with dissemination to the spleen, liver, kidneys, and thymus. Treatment with co-trimoxazole was more effective than treatment with doxycycline irrespective of the size of the particles inhaled. Doxycycline was more effective against the 12 µm particle inhalational infection as evidenced by increased time to death. However, both treatment regimes exhibited significant relapse when therapy was discontinued with massive enlargement and abscessation of the lungs, spleen, and cervical lymph nodes observed.

Colour photographs for screening in neovascular age-related macular degeneration: are they necessary?

AIMS: To investigate whether optical coherence tomography (OCT) with associated infra-red images provide enough information to determine treatment decisions in the management of neovascular age-related macular degeneration (nAMD), or whether retinal colour photography is also necessary. METHODS: In all, 87 OCT scans of 82 eyes with nAMD undergoing monitoring post ranibizumab treatment were taken using the Zeiss Stratus (Carl Zeiss Meditec, Jena, Germany; n=87) together with their corresponding infra-red images. Fundus colour photographs were also taken. These images were reviewed by an experienced assessor, and a ranibizumab treatment decision was made during a multidisciplinary team retinal image review meeting. RESULTS: In all, 30 OCT scans (34.5%) showed intraretinal or subretinal oedema. A total of 24 colour photographs (19.5%) demonstrated retinal haemorrhage. Corresponding OCT infra-red images gave poor sensitivity in detecting haemorrhages (0.176). In 16.7% of decisions to treat, haemorrhage alone was the deciding factor. Signs of disease activity seen only on colour photography were the deciding factor in clinical decisions for 8% of scans assessed. CONCLUSIONS: The presence or increase of intra-retinal oedema is an important sign of activity triggering ranibizumab retreatment, but some eyes show signs of retinal haemorrhage without coexisting oedema. These haemorrhages are often only seen on either colour imaging or fundoscopy and are unclear or invisible on OCT scans and infra-red images. Therefore, although retinal colour photography creates additional expense, it is indispensable for making informed retreatment decisions, if patients are monitored using retinal imaging alone.

A comparison of Plague vaccine, USP and EV76 vaccine induced protection against Yersinia pestis in a murine model.

The median lethal dose (MLD) of a pathogenic strain of Yersinia pestis was established by three routes of administration in three strains of mouse. There was no significant difference between the MLDs in the different strains of mouse. The MLD by the subcutaneous route in Balb/C and an outbred line was approximately 1 c.f.u.; the MLD following intraperitoneal administration was tenfold higher. There were significant differences in the mean times to death after administration of the challenge by different routes. The relative efficacy of a live attenuated vaccine strain of Y. pestis (EV76) was compared with that of the formaldehyde-killed vaccine (Plague vaccine, USP). EV76 protected against high challenge doses (up to 5.75 x 10(6) MLD), though immunized animals showed side effects of varying severity. The killed vaccine was less effective in terms of dose-protection (deaths occurred after challenge with 4000 MLD) and several of the vaccinated animals suffered sub-lethal, plague-related sequelae to the challenge.

Formaldehyde Solution Effectively Inactivates Spores of Bacillus anthracis on the Scottish Island of Gruinard.

Gruinard Island was heavily contaminated with the spores of virulent Bacillus anthracis during biological weapons trials in World War II. However, an extensive survey in 1979 showed that most of the island was not contaminated. In the early 1980s, a more intensive survey revealed that the contamination was largely confined to the top 8 cm of the soil in a 2.6-ha area of the 211-ha island. Small-scale tests showed that the spores could be inactivated by drenching the soil with fluid biocides. A solution of 5% formaldehyde in seawater applied by surface spray to each square meter of ground was shown to be the most effective treatment and was utilized for large-scale decontamination of the affected areas. Following this treatment, extensive sampling revealed that most of the spores of B. anthracis had been inactivated. Isolated pockets of surviving spores were treated further. A flock of sheep was then allowed to graze over the entire island for 5 months; none contracted anthrax.