Incompatibility of contrast agents with intravascular medications. Work in progress

In vitro and in vivo precipitation of iodinated contrast agents when ioxaglate and papaverine are given together has been reported. To verify these reports and to investigate other medications not previously tested, the authors analyzed mixtures of contrast agents and medications in vitro with a light spectrophotometer and observed them for visible precipitates for up to 120 minutes. Previously reported incompatibilities between ionic or low-osmolality contrast media and medications were verified, and several new incompatibilities were discovered. No incompatibilities were found when the drugs tested were mixed with the new nonionic contrast media.     

Diet of adults living in houses in multiple occupation.

This study describes the diet and lifestyle of people living in houses in multiple occupation (HMO). A census was taken from a random sample of 400 HMOs in Southampton. Interviews were carried out with a random sample of 73 adult residents from the HMOs. A group of 34 people recently rehoused by the local council were interviewed for comparison. The HMO group had a lack of adequate cooking facilities compared to the council group. A kitchen was used to cook a meal every day by only 53% of the HMO and 77% of the council group. The HMO group spent more money on rent and food than the council group. Women in the HMO group had lower intakes of protein, fat and calcium than women in the council group. Housing conditions appeared to have some influence on nutrient intake. However, the HMO and council groups behaved in a similar way for a number of dietary habits. In low-income groups such as those studied here, factors other than housing conditions appear to influence food intake.     

Chlamydial etiology of acute lower respiratory tract infections in children in the Sudan

The role of Chlamydia pneumoniae in 110 Sudanese children with signs of acute lower respiratory tract infections (ALRI) was investigated. Four (3.6%) had evidence of C. pneumoniae infection, of whom 3 were culture-positive, while 1 had an antibody response suggesting a recent infection. IgG antibodies at a titer of ≥1:32 to C. pneumoniae, Chlamydia psittaci and Chlamydia trachomatis were detected in 27 (24.5%), 27 (24.5%) and 7 (6.4%) of the 110 ALRI cases, respectively. C. pneumoniae, C. trachomatis or C. psittaci were not detected in nasopharyngeal secretions from any of 110 patients when fluorescence-labeled specific monoclonal antibodies were used. In a seroepidemiological survey, 318 healthy Sudanese persons aged between 1 month and 67 years were studied for C. pneumoniae antibodies.     

Apparent lack of synergism between heparin and dihydroergotamine in prevention of deep vein thrombosis after elective hip replacement: a randomised double-blind trial reported in conjunction with an overview of previous results.

We report the results of a double-blind, randomised trial of venous thrombosis (VT) prevention in 117 patients having elective hip replacement where low dose heparin alone (5,000 IU sodium heparin given subcutaneously [sc] 8 hourly until the seventh postoperative day) was compared with low dose heparin plus dihydroergotamine (DHE; 0.5 mg, given 8 hourly by sc injection). The trial end point consisted of VT discovered through bilateral ascending venography done routinely on the seventh postoperative day. VT developed in 34% of patients given heparin/DHE (95% confidence interval = 22% - 47%) compared with 24% in those given low dose heparin alone (95% confidence interval = 14% - 37%; p = 0.34), difference = 10% (95% confidence interval = -7% to +26%). Corresponding figures for the incidence of proximal (above-knee) thrombosis were 17% and 14% (95% confidence intervals = 8% - 29% and 6% - 25% respectively). These results are discussed in the context of a detailed overview of published evidence concerning VT prevention with heparin/DHE after hip replacement and we conclude it is unlikely that heparin/DHE is markedly superior to low dose heparin alone in this clinical setting.     

Sweet's syndrome—therapy with cyclosporin

We report the case of a 39-year-old female patient suffering from Sweet's syndrome after an upper respiratory tract infection. Cyclosporin A at a dose of 10 mg/kg per day was given as initial treatment. Skin lesions and general malaise resolved within 9 days. The cyclosporin dose was decreased within 21 days, without recurrence of the eruption. Cyclosporin is a potent inhibitor of T lymphocytes, but affects granulocyte and monocyte functions as well. Success of treatment in our case shows that cyclosporin represents an alternative to steroid treatment in patients with Sweet's syndrome.     

Variations in the evaluation of colorectal cancer risk

OBJECTIVES: To test the variability in estimating cancer risk and demonstrate the consequences that subjectivity has on patient care. SUBJECTS AND METHODS: Forty-three clinicians were each asked to assess 40 symptomatic colorectal referrals. Each clinician was provided with a comprehensive history on the 40 patients. The clinicians graded the referral according to a malignancy risk score, decided on the required first line investigation and the priority of that investigation. The main outcome measures used was accuracy in cancer detection and appropriateness of investigations selected. RESULTS: There was a wide degree of variation among all clinicians grading both benign and malignant disease with the overall correct classification of 54% (P-value of <0.001). On average, the clinicians correctly diagnosed 71.3% of the cancer patients as compared to 44% of the benign patients. Of the cancer patients, 47% were correctly classified as an urgent referral whilst 52% of the benign patients were over classified and graded as an urgent referral. The mean number chosen by clinicians to have a flexible sigmoidoscopy as the appropriate first investigation was 13 (of 40 patients); this was despite the diagnosis being possible in all cases with a flexible sigmoidoscopy. The choice to use full colonic investigation was seen throughout all disciplines. Junior doctors demonstrated the highest tendency choosing full colonic investigation in 92.3%. Consultants and senior grades showed the least tendency to choose full colonic imaging although even here colonoscopy or barium enema represented 48.5%. CONCLUSION: Subjective assessment of cancer referrals is a significant problem that needs to be confronted. Improvements are needed to resolve the inherent problems of subjectivity and operator bias if uniform quality of patient care and best use of resources is to be achieved.     

Time-resolved particle image velocimetry and laser doppler anemometry study of the turbulent flow field of bileaflet mechanical mitral prostheses

Dynamic particle image velocimetry (PIV) was applied to the study of the flow field associated with prosthetic heart valves. The results were compared with those of laser Doppler anemometry (LDA). Anatomically and antianatomically oriented Jyros (JR) and St. Jude Medical (SJM) valves were compared in the mitral position to study the effects of valve design on the downstream flow field. The experimental program used a dynamic PIV system utilizing high-speed, high-resolution video to map the true time-resolved velocity field inside the simulated ventricle. This system was complemented by a study using the more traditional LDA system for comparison. Based on the experimental data, the following general conclusions can be made. High-resolution dynamic PIV can capture true chronological changes in the velocity and turbulence fields. It also produces very detailed velocity and turbulence information comparable to the LDA results. In the vertical measuring plane that passes both the center of the aortic and mitral valves (A-A section), the two valves (the SJM and the JR) show distinct circulatory flow patterns when the valve is installed in the antianatomical orientation. Small differences in valve design can generate noticeable differences, particularly during the accelerating flow phase. The SJM valve maintains a relatively high velocity through the central orifice; the curved leaflets of the JR valve generate higher velocities with a divergent flow during the accelerating and peak flow phases. In the velocity field directly below the mitral valve and normal to the previous measuring plane (B-B section), where characteristic differences in valve design will be visible, symmetrical twin circulations were observed because of the divergent nature of the flow generated by the two inclined half-disks installed in the antianatomical orientation. The SJM valve, with a central downward flow near the valve, is contrasted with the JR valve, which has a peripheral downward circulation with higher, turbulent stresses.