An Environmental Scan of the National and Provincial Diagnostic Reference Levels in Canada for Common Adult Computed Tomography Scans

Several regulatory bodies have agreed that low-dose radiation used in medical imaging is a weak carcinogen that follows a linear, non-threshold model of cancer risk. While avoiding radiation is the best course of action to mitigate risk, computed tomography (CT) scans are often critical for diagnosis. In addition to the as low as reasonably achievable principle, a more concrete method of dose reduction for common CT imaging exams is the use of a diagnostic reference level (DRL). This paper examines Canada's national DRL values from the recent CT survey and compares it to published provincial DRLs as well as the DRLs in the United Kingdom and the United States of America for the 3 most common CT exams: head, chest, and abdomen/pelvis. Canada compares well on the international scale, but it should consider using more electronic dose monitoring solutions to create a culture of dose optimization.     

Arrogance in the Workplace: Implications for Mental Health Nurses

Cultures of performativity may contribute to organizational and individual arrogance. Workplace organizations have individuals who at various times will display arrogance, which may manifest in behaviours, such as an exaggerated sense of self-importance, dismissiveness of others, condescending behaviors and an impatient manner. Arrogance is not a flattering label and irrespective of the reason or the position of power, in the context of organizational behaviors, may not be useful and may even be detrimental to the work environment. Thus, it is timely to reflect on the implications of arrogance in the workplace. Advocacy and empowerment can be undermined and relationships adversely impacted, including the achievement of positive consumer outcomes. This paper provides an introduction to arrogance, and then discusses arrogance to promote awareness of the potential consequences of arrogance and its constituent behaviors.     

Approximation of diffuse attenuation,Kd, for MODIS high-resolution bands

A high resolution depth attenuation product (K_d^hires) was developed using MODIS 500 m and 250 m spectral bands. The K_d^hires was compared with Wang’s operational K_d for the Chesapeake Bay. Minimal differences were observed between the two methods, with greatest deviation occurring in areas of high turbidity in the tributaries. After tuning the new K_d^hires, the mean absolute error and bias between the two algorithms was 0.22 m^?1 and 0.026 m^?1, indicating good agreement. Higher spatial resolution provides for improved retrievals along the coast and into the narrow sections of the tributaries, coinciding with areas of concern to estuarine health and coastal management applications.     

Prevention of Descending Pneumonia in Rats with Perflubron-delivered Tobramycin

OBJECTIVES: Patients undergoing emergent endotracheal intubation are at increased risk for developing pneumonia. Although numerous strategies have been investigated to reduce ventilator-associated pneumonia (VAP), the incidence of VAP and its associated mortality remains high. This investigation tested the hypothesis that LiquiVent (Alliance Pharmaceutical, San Diego, CA-LV) delivered antibiotics (via spray-dried microspheres-SDM) would improve survival in a rat model of descending gram-negative pneumonia. METHODS: Wistar rats (n = 49) were randomized to receive prophylaxis with 1). nothing (controls); 2). intramuscular (IM) tobramycin, 3). intratracheal LV plus SDM shells (vehicle), 4). intratracheal LV plus SDM shells plus IM tobramycin, or 5). intratracheal LV plus SDM containing 1 mg/kg of tobramycin. All interventions were given 24 hours before a bacterial challenge with 10(8) colony-forming units of intratracheal Klebsiella pneumoniae. Mortality at ten days was the sole outcome measure. Survival in individual groups was compared with controls by Fisher's exact test with Bonferroni correction for multiple comparisons. RESULTS: All animals in the control group died of pneumonia within ten days of bacterial inoculation (0% survival). Prophylaxis with either IM tobramycin or SDM vehicle plus IM tobramycin provided no protection (0% survival). This is in sharp contrast to the cohort receiving pretreatment with tobramycin-containing SDM delivered via LV, in which 60% of the animals survived to study completion (p < 0.05). CONCLUSIONS: Prophylaxis with SDM containing antibiotics delivered in low-dose LV provided significant protection in a rat model of descending gram-negative pneumonia. These data support the hypothesis that perfluorocarbon-delivered intratracheal antimicrobials may be useful in the prevention of VAP.