[SARS-CoV-2-How can and must medical personnel protect themselves?] / SARS-CoV-2 ­ Wie kann und muss sich medizinisches Personal schützen?

The SARS-CoV­2 pandemic represents a great challenge worldwide not only under the aspect of treatment but also of prevention. The infection curve could be flattened by the rapid implementation of simple distance and hygiene measures. In order to ensure current and future patient care in conjunction with protection of medical personnel working in the healthcare system during this pandemic, adequate protective equipment is essential. Routine care can only be resumed if there is sufficient and adequate personal protective equipment (PPE). If recommended hygiene protective measures including the necessary PPE are seriously taken into account both elective interventions and emergency care can be carried out without an increased risk of infection. This is very important in vascular surgery with a high proportion of urgent and emergency disease management.

A Grading Score for Colon Preservation Injury in the Rat.

BACKGROUND: Colon transplantation is rarely performed because of the fear for an advanced ischemic injury that may favor septic complications. Systematic studies on colon preservation are missing. The score used to evaluate the preservation injury of the colon is adapted from that used for the small intestine, despite histological and biological differences between the two organs. We studied sequentially the tissue changes in the rat colon during prolonged cold storage (CS) in histidine-tryptophan-ketoglutarate (HTK) solution and designed a grading score specific for the colon. METHODS: Large bowels of Sprague-Dawley rats (n = 9) were perfused in situ with HTK and stored at 4°C for 6 hours, 12 hours, 18 hours, and 24 hours. Samples from the proximal colon were stained with hematoxylin-eosin and alcian blue. Tight junction protein zonulla occludens (ZO)-1 was also studied. RESULTS: Minimal subepithelial edema (hallmark of small intestinal preservation injury) was observed throughout the 24 hours of CS. The two major changes observed during the colonic CS were progressive submucosal edema and the depletion of Goblet cells (GC). The submucosal edema was absent at 6 hours, started after 12 hours, and become significant (over 50% of the circumference) after 18 hours of CS. Depletion of GC started in the luminal half of the crypts between 12 and 18 hours of CS, and all samples revealed significant GC depletion only after 24 hours. The overall appearance of the mucosa was little affected under the CS, and ZO-1 expression was frequently maintained throughout the first 18 hours. CONCLUSIONS: The colon is more resilient to cold ischemia than the small bowel and maintains its histological epithelial features longer than the small intestine. On the basis of these serial observations, we suggest the following grading score: grade 0: normal mucosa, repleted GC, mucosa adhering to the muscular layer; grade 1: limited submucosal edema, repleted GC; grade 2: limited submucosal edema, GC depletion in the luminal half of the crypts; grade 3: advanced (>50% of circumference) submucosal edema, GC depletion in the luminal half of the crypts; grade 4: advanced mucosal injury (edema, GC depletion, epithelial breakdown).

Optimal Solution Volume for Luminal Preservation: A Preclinical Study in Porcine Intestinal Preservation.

BACKGROUND: Rodent studies suggest that luminal solutions alleviate the mucosal injury and prolong intestinal preservation but concerns exist that excessive volumes of luminal fluid may promote tissue edema. Differences in size, structure, and metabolism between rats and humans require studies in large animals before clinical use. METHODS: Intestinal procurement was performed in 7 pigs. After perfusion with histidine-tryptophan-ketoglutarate (HTK), 40-cm-long segments were cut and filled with 13.5% polyethylene glycol (PEG) 3350 solution as follows: V0 (controls, none), V1 (0.5 mL/cm), V2 (1 mL/cm), V3 (1.5 mL/cm), and V4 (2 mL/cm). Tissue and luminal solutions were sampled after 8, 14, and 24 hours of cold storage (CS). Preservation injury (Chiu score), the apical membrane (ZO-1, brush-border maltase activity), and the electrolyte content in the luminal solution were studied. RESULTS: In control intestines, 8-hour CS in HTK solution resulted in minimal mucosal changes (grade 1) that progressed to significant subepithelial edema (grade 3) by 24 hours. During this time, a gradual loss in ZO-1 was recorded, whereas maltase activity remained unaltered. Moreover, variable degrees of submucosal edema were observed. Luminal introduction of high volumes (2 mL/mL) of PEG solution accelerated the development of the subepithelial edema and submucosal edema, leading to worse histology. However, ZO-1 was preserved better over time than in control intestines (no luminal solution). Maltase activity was reduced in intestines receiving luminal preservation. Luminal sodium content decreased in time and did not differ between groups. CONCLUSIONS: This PEG solution protects the apical membrane and the tight-junction proteins but may favor water absorption and tissue (submucosal) edema, and luminal volumes >2 mL/cm may result in worse intestinal morphology.

Lenalidomide with or without erythropoietin in transfusion-dependent erythropoiesis-stimulating agent-refractory lower-risk MDS without 5q deletion.

After failure of erythropoiesis-stimulating agents (ESAs), lenalidomide (LEN) yields red blood cell (RBC) transfusion independence (TI) in 20-30% of lower-risk non-del5q myelodysplastic syndrome (MDS). Several observations suggest an additive effect of ESA and LEN in this situation. We performed a randomized phase III study in 131 RBC transfusion-dependent (TD, median transfusion requirement six RBC units per 8 weeks) lower-risk ESA-refractory non-del5q MDS. Patients received LEN alone, 10 mg per day, 21 days per 4 weeks (L arm) or LEN (same schedule) + erythropoietin (EPO) beta, 60,000 U per week (LE arm). In an intent-to-treat (ITT) analysis, erythroid response (HI-E, IWG 2006 criteria) after four treatment cycles (primary end point) was 23.1% (95% CI 13.5-35.2) in the L arm and 39.4% (95% CI 27.6-52.2) in the LE arm (P=0.044), while RBC-TI was reached in 13.8 and 24.2% of the patients in the L and LE arms, respectively (P=0.13). Median response duration was 18.1 and 15.1 months in the L and LE arms, respectively (P=0.47). Side effects were moderate and similar in the two arms. Low baseline serum EPO level and a G polymorphism of CRBN gene predicted HI-E. Combining LEN and EPO significantly improves erythroid response over LEN alone in lower-risk non-del5q MDS patients with anemia resistant to ESA.