Risk factors for Clostridium difficile-associated diarrhea on an adult hematology-oncology ward

Nosocomial diarrhea caused by Clostridium difficile causes significant morbidity and mortality in an increasing proportion of hospitalized patients annually. This case-control study of patients admitted to the hematology-oncology ward of a tertiary academic medical center over a 2-year period demonstrates that patients with Clostridium difficile-associated diarrhea (CDAD) were 22 times more likely than ward-matched controls with diarrhea to have received any antibiotic either during hospitalization or in the month preceding admission (p < 0.005), and they were nearly three times as likely as controls to have received a cephalosporin during the same period (p < 0.005). Diarrhea among lung cancer patients was approximately three times more likely to be caused by this organism than to be due to other causes (p = 0.04). A trend towards CDAD patients receiving higher numbers of different antibiotics during hospitalization (3.3 vs. 2.6, 95%CI −1.42–0.02, p = 0.06) was noted. Administration of interleukin-2 either during hospitalization or in the 30 days preceding admission was seven times more likely to have occurred in CDAD cases (p = 0.04), raising the question of whether or not this agent increases risk.     

Diet Quality of Elite Australian Athletes Evaluated Using the Athlete Diet Index

While athletes’ nutrient intakes have been widely reported, few studies have assessed the diet quality of athletes. This is the first study to evaluate the diet quality of athletes using the purpose-built Athlete Diet Index (ADI). A convenience sample of 165 elite athletes from Australian sporting institutions completed the ADI online, with subsequent automated results provided to their respective accredited sports dietitians (ASDs). At the completion of athlete participation, ASDs (n = 12) responded to a range of survey items using a Likert scale (i.e., 1 = strongly agree to 5 = strongly disagree) to determine the suitability of the ADI in practice. Differences in ADI scores for demographics and sport-specific variables were investigated using independent t-tests, analysis of variance (ANOVA) and Bonferroni multiple comparisons. Spearman’s rank correlation was used to assess the association between total scores and demographics. The mean total ADI score was 91.4 ± 12.2 (range 53–117, out of a possible 125). While there was no difference in total scores based on demographics or sport-specific variables; team sport athletes scored higher than individual sport athletes (92.7 vs. 88.5, p < 0.05). Athletes training fewer hours (i.e., 0–11 h/week) scored higher on Dietary Habits sub-scores compared with athletes training more hours (≥12 h/week; p < 0.05), suggesting that athletes who train longer may be at risk of a compromised dietary pattern or less than optimal nutrition practices that support training. Most (75%) ASDs surveyed strongly agreed with the perceived utility of the ADI for screening athletes and identifying areas for nutrition support, confirming its suitability for use in practice.     

Cone-beam tomography with discrete data sets

Sufficiency conditions for cone-beam data are well known for the case of continuous data collection along a cone-vertex curve with continuous detectors. These continuous conditions are inadequate for real-world data where discrete vertex geometries and discrete detector arrays are used. In this paper we present a theoretical formulation of cone-beam tomography with arbitrary discrete arrays of detectors and vertices. The theory models the imaging system as a linear continuous-to-discrete mapping and represents the continuous object exactly as a Fourier series. The reconstruction problem is posed as the estimation of some subset of the Fourier coefficients. The main goal of the theory is to determine which Fourier coefficients can be reliably determined from the data delivered by a specific discrete design. A Fourier component will be well determined by the data if it satisfies two conditions: it makes a strong contribution to the data, and this contribution is relatively independent of the contribution of other Fourier components. To make these considerations precise, we introduce a concept called the cross-talk matrix. A diagonal element of this matrix measures the strength of a Fourier component in the data, while an off-diagonal element quantifies the dependence or aliasing of two different components. One reasonable approach to system design is to attempt to make the diagonal elements of this matrix large and the off-diagonal elements small for some set of Fourier components. If this goal can be achieved, simple linear reconstruction algorithms are available for estimating the Fourier coefficients. To illustrate the usefulness of this approach, numerical results on the cross-talk matrix are presented for different discrete geometries derived from a continuous helical vertex orbit, and simulated images reconstructed with two linear algorithms are presented.     

The effects of scheduled intern rotation on the cost and quality of teaching hospital care

We studied the effect of scheduled intern rotations on the cost and quality of inpatient care at one teaching hospital. For all discharges from the internal medicine service between 1980 and 1986, we identified 1,705 rotation patients and 3,141 no-rotation patients. Using linear or logistic regression analysis to control for baseline differences, we evaluated for the effect of rotation. We found that rotation was significantly related to longer length of hospital stay, b = 0.341 days, p = 0.001, and higher hospital charges (for log charges, b = 0.053, p = 0.016. Hospital deaths, nursing home placements, and 30-day readmissions were not significantly related to rotation, p > 0.1. These results suggest that the systematic discontinuity induced by scheduled intern rotations may be another source of increased health care costs experienced at teaching hospitals.     

Predictive value of angiotensin II antagonists in renovascular hypertension

An angiotensin II antagonist, sarcosine-1, threonine-8 angiotensin II ( [Sar1, Thr8] A II), was infused preoperatively in 14 patients with renal artery stenosis. Postoperative graft patency was documented by renal flow scan in 13 patients. One of these required antihypertensive therapy immediately after surgery, while the other 12 had a significant BP reduction in the first postoperative week (141 +/- 3.7 to 110 +/- 1.6 mm Hg). With longer follow-up, six patients remained normotensive (group 1), while the other six had "residual hypertension" (group 2). There was no significant difference between the two groups as regards age, preoperative BP level, plasma renin activity, blood volume, or response to [Sar1, Thr8] A II. In contrast, clinical signs were most helpful in predicting response to surgery. "Cured" patients had shorter duration of hypertension (less than one year) than patients with residual hypertension, and less impairment of renal excretory function; three patients in group 2 but none in group 1 had a history of malignant hypertension. The decision to operate remains a multifactorial evaluation and cannot be based on results of any single test alone.     

Support perfusion for liver transplantation

Addenbrooke's Hospital, Cambridge, UK, has had an ongoing orthotopic liver transplant programme since 1968. Various support bypass techniques have been used intermittently since 1977. In 1990 bypass was needed for 38% of adult liver transplants, and bypass standby was provided for a further 25%. Adult liver recipients (high-risk) are selected for bypass in accordance with a number of surgical and anaesthetic criteria in order to maximize patient benefit and minimize risk. Before the start of the operation two cannulae (8 or 10 Fg) are placed into left and right internal jugular veins and/or the left brachial vein for rapid volume replacement. Femoral and portal vein cannulation (16 to 22 Fg) can quickly be achieved for splanchnic venous drainage to a heparin coated Biomedicus bypass system. This technique provides flows of 1.5 to 2.5 litres per minute with modest perfusion pressures (around 120mmHg) and provides adequate surgical venous decompression and circulatory support during the anhepatic phase.