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BACKGROUND Although females have a lower baseline hemoglobin (Hb) compared to males, it is unknown whether females have a greater tolerance for anemia when hospitalized. We tested the hypothesis that females tolerate severe anemia better than males, with decreased inpatient mortality in this setting. STUDY DESIGN AND METHODS We conducted a retrospective cohort study in 230,644 adult patients admitted to Johns Hopkins Hospital from January 2009 to June 2016. The relationships between nadir Hb and percentage change in Hb with inpatient mortality were assessed for nontransfused males and females. A multivariable logistic regression was used to determine risk‐adjusted differences between males and females for the likelihood of inpatient mortality at nadir Hb levels of 5, 6, and 7 g/dL. RESULTS Males had increased mortality when nadir Hb was 6.0 g/dL or less (p < 0.05), whereas females did not. The risk‐adjusted likelihood for inpatient mortality was greater for males compared to females at a nadir Hb of 6 g/dL or less (odds ratio, 1.84; 95% confidence interval, 1.09‐3.16) (p = 0.02), but this sex‐related difference was not significant at a nadir Hb of 5 or 7 g/dL or less. Inpatient mortality increased significantly in both males and females when the percentage decrease in Hb was greater than 50% from baseline (p < 0.05). CONCLUSIONS Compared to males, females tolerate a lower nadir Hb, but a similar percentage change in Hb, before an increase in inpatient mortality is recognized. The findings suggest that females may be “preconditioned” to tolerate anemia better than males.

Compared to other traumatic injuries, GSW injuries are associated with substantially greater blood utilization and mortality. Trauma centers treating GSW injuries should have ready access to all blood components and ability to implement massive transfusions.

Quantitative diffusion MRI (dMRI) is a promising technique for evaluating the spinal cord in health and disease. However, low signal-to-noise ratio (SNR) can impede interpretation and quantification of these images. The purpose of this study is to evaluate a denoising approach, Patch2Self, to improve the quality, reliability, and accuracy of quantitative diffusion MRI of the spinal cord. Patch2Self is a self-supervised learning-based denoising method that leverages statistical independence of noise to suppress signal components strictly originating from random fluctuations. We conduct three experiments to validate the denoising performance of Patch2Self on clinical-quality, single-shell dMRI acquisitions with a small number of gradient directions: 1) inter-session scan-rescan in healthy volunteers to evaluate enhancements in image contrast and model fitting; 2) repeated intra-session scans in a healthy volunteer to compare signal averaging to Patch2Self; and 3) assessment of spinal cord lesion conspicuity in a multiple sclerosis group. We find that Patch2Self improves intra-cord contrast, signal modeling, SNR, and lesion conspicuity within the spinal cord. This denoising approach holds promise for facilitating reliable diffusion measurements in the spinal cord to investigate biological and pathological processes.