Red blood cell survival was determined in patients with aortic valvular disease, postoperative patients with aortic valvular ball-valve prostheses and postoperative patients with multiple ball-valve prostheses. The red blood cell survival was reduced in the majority of patients in each group when compared with the red blood cell survival from a normal control group.
A detailed analysis of the survival curves suggested that in many patients there was more than one population of red blood cells. The first population displayed rapid random destruction. This population was not present in normal persons in the control group. The second population showed the usual decline in radioactivity due to random destruction and loss of the red cell label due to elution. The shortened red blood cell survival in some patients was due to a large percentage of the first population of randomly destroyed red blood cells, in other patients to an accelerated rate of destruction of the usual single population of cells while others had a combination of the two mechanisms.
A mechanism of mechanical hemolysis due to increased intracardiac turbulence was suggested as a cause for the shortened survival. When the turbulence was increased by a leak around the aortic or mitral valve prosthesis the red blood cell survival was found to be further decreased. In some cases this reduction in survival was enough to produce hemolytic anemia.
The Coombs antiglobulin test was positive in three patients. The suggestion was made that the development of autoantibodies to red blood cells was secondary to increased destruction of red blood cells.
Background:Non-English speakers (NES) as a proportion of the United States population have steadily increased in recent years. There remains substantial risk of excluding NES from research.Objective:To assess whether the percentage of emergency medicine (EM) studies that exclude Non-English speakers from participation has changed with time.Methods:In a structured fashion, the lead investigator analyzed all original research articles in Academic Emergency Medicine and Annals of Emergency Medicine retrospectively for 2004 and prospectively for 2014. An independent investigator conducted a blind review of a sample of articles to assess for interobserver agreement. Demographic data were analyzed using descriptive statistics. Chi-square, t-tests, and linear regression models were utilized; alpha set at 0.05. Cohen’s kappa calculated to assess interrater reliability.Results:We included a total of 236 original research articles. Overall, 11% excluded NES from research (10% AEM, 12% Annals). Cohen’s kappa (nonweighted) was 0.73. Comparing all articles in 2004 vs. 2014, research excluded NES 6% vs. 16% of the time respectively (P=0.02). This was not statistically significant when comparing year to year for AEM (7.3% vs. 14.5%; P=0.12) and Annals (6.7% vs. 19%; P=0.06) separately. Factors affecting NES exclusion included type of study design (P<0.001), geographic area (P=0.009) and hospital type (P=0.035). Interestingly, 42% of articles failed to mention language as an exclusion or inclusion criteria.Conclusion:We found that the percentage of articles excluding NES from EM research increased between 2004 and 20014. Further, many investigators do not report whether NES are excluded/included in their studies.
Red cell survival times were measured in patients with mitral valvular disease, mitral ball-valve prostheses, and multiple valve prostheses. Red cell survival was shortened in patients with mitral valvular disease but not in patients who had insertion of a normally functioning mitral prosthesis or after mitral commissurotomy.
Mean red cell survival was also reduced in patients who had normal mitral prostheses associated with aortic valvular disease and in patients with a leak around the mitral prosthesis.
Mean red cell survival was the same in patients with multiple prostheses and in patients with a single aortic prosthesis. If a leak developed around the mitral prosthesis in patients with multiple prostheses, hemolytic anemia could develop. Renal excretion of iron and iron deficiency were demonstrated in two patients with traumatic hemolytic anemia. The urinary iron loss apparently exceeds the capacity for intestinal absorption, and parenteral iron would seem to be indicated for replacement.
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