Bloodstream infections after invasive nonsurgical cardiologic procedures

OBJECTIVE: To define the incidence, risk factors, and characteristics of bloodstream infections (BSIs) after invasive nonsurgical cardiologic procedures (ICPs). METHODS: Retrospective case-control study; multivariate analysis. RESULTS: Between January 1991 and December 1998, 22 006 ICPs were performed in our hospital and 25 BSIs were documented within 72 hours after ICP. Overall incidence of bacteremia was 0.11% (25 cases) (0.24% after percutaneous transluminal coronary angioplasty [14 cases of 5625 patients], 0.06% [corrected] after diagnostic cardiac catheterization [9 cases of 14 034 patients], and 0.08% [corrected] after electrophysiologic studies [2 cases of 2347 patients]). These 25 patients with bacteremia were compared with 50 controls randomly selected among patients who underwent an ICP but did not have BSIs. Patient-related risk factors for BSI were age older than 60 years (20 cases [80%] vs 28 controls [56%]), valvular disease (4 [16%] vs 1 [2%]), congestive heart failure (7 [28%] vs 1 [2%]), indwelling bladder catheter before the ICP (5 [20%] vs 1 [2%]), more than 1 puncture for the ICP (5 [20%] vs 3 [6%]), a prolonged procedure (83.7 vs 65.1 minutes); and/or more than 1 ICP performed (2 [8%] vs 0). Multivariate analysis identified the presence of congestive heart failure (odds ratio, 21; 95% confidence interval, 6.8-66.0) and age older than 60 years (odds ratio, 1.9; 95% confidence interval, 1.9-6.3) as independent risk factors for BSI after ICP. Bloodstream infection was detected a median of 1.7 days after the procedure. Gram-negative bacteremia accounted for 17 cases (68%) of the BSIs. Among the patients with BSI, the duration of hospital stay was significantly increased (21 vs 6 days). The overall mortality rate was 0.009% for patients who underwent an ICP (8.0% for the 25 patients with bacteremia documented within 72 hours after ICP). CONCLUSIONS: Bloodstream infection should be included among the potential complications of ICP. Elderly patients with recent congestive heart failure episodes constitute a subgroup with a higher risk of postprocedure bacteremia. Therapy with antimicrobial agents against gram-positive and gram-negative bacteremia should be initiated after performing blood cultures in patients with signs suggestive of infection.     

Ct-based finite element models can be used to estimate experimentally measured failure loads in the proximal femur

The objective of this experimental finite element (FE) study was to assess the accuracy of a simulation model estimate of the experimentally measured fracture load of the proximal femur in a sideways fall. Sixty-one formalin-fixed cadaver femora (41 female and 20 male) aged 55-100 years (an average of 80 years) were scanned with a multi-detector CT scanner and were mechanically tested for failure in a sideways fall loading configuration. Twenty-one of these femurs were used for training purposes, and 40 femurs were used for validation purposes. The training set FE models were used to establish the strain threshold for the element failure criteria. Bi-linear elastoplastic FE analysis was performed based on the CT images. The validation set was used to estimate the fracture loads. The Drucker-Prager criterion was applied to determine the yielding and the maximum principal stress criteria and the minimum principal strain criteria for element failure in tension and in compression, respectively. The estimated fracture load values were highly correlated with the experimental data (r=0.931; p<0.001). The slope was 0.929, with an intercept of 258 N, which was not significantly different from 1 and 0, respectively. The study shows that it is possible to estimate the fracture load with relatively high accuracy in a sideways fall configuration by using the CT-based FE method. This method may therefore be applied for studying the biomechanical mechanisms of hip fractures.     

Fascia lata plasty in recurrent posterior dislocation after total hip arthroplasty

With a soft-tissue plasty, stability could be obtained in 17 of 22 patients with unstable hips after total hip arthroplasty. While in 16 of 18 patients with a posterior instability stability was achieved, only 1 of 3 patients with a unstable hip for dislocation in all directions was successfully treated. No stability could be achieved in one patient with a hip which dislocated anteriorly. The method described should only be used for posterior recurrent dislocations after total hip arthroplasty.     

Managing MICA Clients in a Modified Therapeutic Community with Enhanced Staffing

To determine how effective a modified therapeutic community (TC) with enhanced mental health staffing would be in treating mentally ill chemical abusing (MICA) clients in a “mainstream” program, Project Return Foundation, Inc. (PRF) conducted a treatment outcome evaluation study involving 438 residents. Client admissions were screened by mental health specialists for Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; American Psychiatric Association, 1994) diagnoses and then placed into one of three diagnostic groups: non-MICA; general MICA (not requiring psychotropic medication); and, severe MICA (requiring psychotropic medication). Clients were administered the Tennessee Self-Concept Scale (TSCS; Roid & Fitts, 1991) after admission and at 6-month intervals thereafter. Results indicated that: (a) the three diagnostic groups were significantly different at initial TSCS testing, with the non-MICA group evidencing the least lowest measures of self-esteem and lesser degrees of psychopathology; the severe MICA group had the lowest psychological scores; (b) all three diagnostic groups showed significant improvement in their TSCS scores after 6 to 7 months of treatment; (c) covariance analyses observed that the three diagnostic groups did not significantly differ at 6 month testing when the initial TSCS testing was taken into account; and, (d) significant gender differences on several TSCS scales were noted, in that women scored lower than men in self-esteem and higher than men in psychopathology. Research limitations and clinical observations are considered.     

Comparison of functional bracing and locked intramedullary nailing in the treatment of displaced tibial shaft fractures.

Thirty-five displaced tibial shaft fractures, treated with functional bracing were compared with 43 similar fractures, treated with locked intramedullary nailing. There were 22 excellent/good results in the brace group and 38 in the nail group. There was one infection in the brace group and three in the nailed group. There were five delayed unions and two nonunions in the brace group and one delayed union in the nail group. The functional results in the nailed group were better than the braced group but locked intramedullary nailing of tibial shaft fractures require special resources and training. Locked intramedullary nailing fullfils all the functional criteria for acceptable fracture care.     

Intensity of exercise is associated with bone density change in premenopausal women

Introduction High-impact exercise is known to be beneficial for bones. However, the optimal amount of exercise is not known. The aim of the present study was to evaluate the association between the intensity of exercise and bone mineral density (BMD). Methods We performed a 12-month population–based trial with 120 women (aged 35–40 years) randomly assigned to an exercise group or to a control group. The intensity of the physical activity of 64 women was assessed with an accelerometer–based body movement monitor. The daily activity was analyzed at five acceleration levels (0.3–1.0 g, 1.1–2.4 g, 2.5–3.8 g, 3.9–5.3 g, and 5.4–9.2 g). BMD was measured at the hip, spine (L1–L4), and radius by dual-energy x–ray absorptiometry. The calcaneus was measured using quantitative ultrasound. Results Physical activity that induced acceleration levels exceeding 3.9 g correlated positively with the BMD change in the hip area (p<0.05–0.001). L1 BMD change correlated positively with activity exceeding 5.4 g (p<0.05) and calcaneal speed of sound with the level of 1.1–2.4 g (p< 0.05). Baseline BMD was negatively associated with the BMD change at the hip. Conclusion The intensity of exercise, measured as the acceleration level of physical activity, was significantly correlated with BMD changes. Bone stimulation is reached during normal physical exercise in healthy premenopausal women. In the hip area, the threshold level for improving BMD is less than 100 accelerations per day at levels exceeding 3.9 g. The preliminary results of the study were presented at the European Society of Biomechanics Conference in ’s–Hertogenbosch, The Netherlands, 7 July 2004, where the presentation received the Clinical Biomechanics Award.