Pre-operative ultrasound mapping before arteriovenous fistula formation: an updated systematic review and meta-analysis.

BACKGROUND: Arteriovenous fistula represents the preferred vascular access for patients with kidney failure requiring hemodialysis. Surgeons have traditionally used physical examination to identify the most suitable vessels. This meta-analysis aims to evaluate whether ultrasound mapping should be routinely performed before arteriovenous fistula creation. METHODS: Medline, Scopus, Web of Science and CENTRAL were systematically searched from inception to November 1, 2022. Randomized controlled trials and cohort studies comparing routine ultrasound mapping to physical examination in terms of arteriovenous fistula patency were included. Meta-analysis was performed by fitting random-effects models. The study protocol has been prospectively registered in PROSPERO (CRD42023402390). RESULTS: Overall, 18 studies were included, comprising 3655 participants. Routine pre-operative ultrasound mapping was associated with significantly lower rates of primary arteriovenous fistula failure (Risk Ratio-RR: 0.56, 95% confidence intervals-CI: 0.37-0.84, low certainty). A significant outcome was observed by separately pooling randomized controlled trials (RR: 0.37, 95% CI: 0.25-0.54). Routine ultrasound mapping was also associated with significantly higher rates of 1-year primary arteriovenous fistula patency (RR: 1.33, 95% CI: 1.19-1.47, moderate certainty). This effect remained significant in the analysis of randomized controlled trials (RR: 1.26, 95% CI: 1.02-1.56). CONCLUSIONS: Implementing routine pre-operative ultrasound mapping of vessels is associated with significantly better outcomes in terms of early arteriovenous fistula failure and primary patency rates at 12 months. Further research should confirm the long-term benefits of routine ultrasound examination and evaluate its cost-effectiveness in different populations.

Favorable outcomes of patients with sickle cell disease hospitalized due to COVID-19: A report of three cases.

Sickle cell disease (SCD) is one of the most frequent and severe monogenic disorders, affecting millions of individuals worldwide. SCD represents a fatal hematological illness, characterized by veno-occlusive events and hemolytic anemia. Hemolytic anemia is caused by abnormal sickle-shaped erythrocytes, which induce parenchymal destruction and persistent organ damage, resulting in considerable morbidity and mortality. During the coronavirus disease 2019 (COVID-19) pandemic, patients with SCD were characterized as a 'high-risk' group due to their compromised immune system, caused by functional hyposplenism, as well as systemic vasculopathy. COVID-19 is characterized by endothelial damage and a procoagulant condition. The present study describes the clinical features, management and outcomes of 3 patients with SCD who were hospitalized due to COVID-19, who all had favorable outcomes despite the complications.