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911.
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913.

Background

The identification of blood donors at risk of developing low hemoglobin (Hb) and subsequent intervention is expected to reduce donation-induced iron deficiency and low Hb among blood donors. This study explores the effects of ferritin-guided iron supplementation for female first-time donors implemented in four of five administrative regions in Denmark.

Study Design and Methods

We included 45,919 female first-time donors in this study. Hb values were determined in donations of included donors during a 2-year follow-up period. For each region, an intervention group (after implementation) and a control group (before implementation) were defined. The primary outcome was Hb below the donation threshold (7.8 mmol/L ~ 12.5 g/dL) at the time of donation, in the control group, and the intervention group, using logistic regression. The secondary outcome was the number of donations per donor given during the follow-up period.

Results

We observed a statistically significant decrease in the risk of female first-time donors experiencing a donation with low Hb after ferritin-guided iron supplementation was introduced: Odds ratio, 0.82; 95% confidence interval (CI), 0.71–0.95. We found a statistically significant increase in the number of donations per donor during the follow-up period after intervention; rate ratio: 1.05, 95% CI: 1.02–1.08.

Discussion

Ferritin-guided iron supplementation led to a significant reduction in the occurrence of low hemoglobin (Hb) levels among Danish female first-time blood donors. The intervention was additionally associated with an increase in the number of donations per donor.  相似文献   
914.
915.
916.

Objective

To investigate the effectiveness and impact of low-pressure pneumoperitoneum (Pnp) on postoperative quality of recovery (QoR) and surgical workspace (SWS) in patients with prostate cancer undergoing robot-assisted radical prostatectomy (RARP).

Patients and Methods

A randomised, triple-blinded trial was conducted in a single centre in Denmark from March 2021 to January 2022. A total of 98 patients with prostate cancer undergoing RARP were randomly assigned to either low-pressure Pnp (7 mmHg) or standard-pressure Pnp (12 mmHg). Co-primary outcomes were postoperative QoR measured via the QoR-15 questionnaire on postoperative Day 1 (POD1), POD3, POD14, and POD30, and SWS assessed intraoperatively by a blinded assessor (surgeon) via a validated SWS scale. Data analysis was performed according to the intention-to-treat principle.

Results

Patients who underwent RARP at low Pnp pressure demonstrated better postoperative QoR on POD1 (mean difference = 10, 95% confidence interval [CI] 4.4–15.5), but no significant differences were observed in the SWS (mean difference = 0.25, 95% CI −0.02 to 0.54). Patients allocated to low-pressure Pnp experienced statistically higher blood loss than those in the standard-pressure Pnp group (mean difference = 67 mL, P = 0.01). Domain analysis revealed significant improvements in pain (P = 0.001), physical comfort (P = 0.007), and emotional state (P = 0.006) for patients with low-pressure Pnp. This trial was registered at ClinicalTrials.gov , NCT04755452, on 16/02/2021.

Conclusion

Performing RARP at low Pnp pressure is feasible without compromising the SWS and improves postoperative QoR, including pain, physical comfort, and emotional state, compared to the standard pressure.  相似文献   
917.

Background

Previous studies have reported Blood type O to confer a lower risk of SARS-CoV-2 infection, while secretor status and other blood groups have been suspected to have a similar effect as well.

Study design and methods

To determine whether any other blood groups influence testing positive for SARS-CoV-2, COVID-19 severity, or prolonged COVID-19, we used a large cohort of 650,156 Danish blood donors with varying available data for secretor status and blood groups ABO, Rh, Colton, Duffy, Diego, Dombrock, Kell, Kidd, Knops, Lewis, Lutheran, MNS, P1PK, Vel, and Yt. Of these, 36,068 tested positive for SARS-CoV-2 whereas 614,088 tested negative between 2020-02-17 and 2021-08-04. Associations between infection and blood groups were assessed using logistic regression models with sex and age as covariates.

Results

The Lewis blood group antigen Lea displayed strongly reduced SARS-CoV-2 susceptibility OR 0.85 CI[0.79–0.93] p < .001. Compared to blood type O, the blood types B, A, and AB were found more susceptible toward infection with ORs 1.1 CI[1.06–1.14] p < .001, 1.17 CI[1.14–1.2] p < .001, and 1.2 CI[1.14–1.26] p < .001, respectively. No susceptibility associations were found for the other 13 blood groups investigated. There was no association between any blood groups and COVID-19 hospitalization or long COVID-19. No secretor status associations were found.

Discussion

This study uncovers a new association to reduced SARS-CoV-2 susceptibility for Lewis type Lea and confirms the previous link to blood group O. The new association to Lea could be explained by a link between mucosal microbiome and SARS-CoV-2.  相似文献   
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