Extracorporeal membrane oxygenation (ECMO): Can we do it ourselves?

Extracorporeal membrane oxygenation (ECMO) is a selectively available therapeutic option, generally available in a large-size referral healthcare system. In a single-center experience of the use of venovenous ECMO for COVID-19 ARDS in a medium-size healthcare system during the pandemic, West et al. in their study have convincingly demonstrated that ECMO can become a broadly available therapeutic option without compromising quality.

Radial Long Sheath Angioplasty for Proximal Severe Flow-Limiting Radial Artery Spasm Using the Dotter Technique.

BACKGROUND: Although studies have continued to demonstrate the advantages of transradial access (TRA) for neurointervention, radial artery spasm (RAS) has remained a frequent cause of TRA failure. Dotter and Judkins initially described a technique to dilate areas of peripheral vascular stenosis by advancing sequentially larger catheters across the lesion over a guidewire. We have presented our institutional experience with the use of a modified Dotter technique with long radial sheaths to dilate areas of proximal flow-limiting RAS. In the present study, we reviewed the use of the Dotter technique for alleviating RAS in patients undergoing TRA for neurointervention. METHODS: We performed a retrospective review of all patients undergoing TRA for neurointervention at our institution from 2018 to 2020 to identify patients with proximal flow-limiting RAS. For the identified patients, a modified Dotter technique had been used to dilate the stenosis. The demographic and periprocedural data were assessed to identify any adverse outcomes. RESULTS: Four patients with severe proximal flow-limiting RAS were identified. In each case, a hydrophilic long radial sheath and vascular dilator were sequentially advanced through the stenosis. In all cases, repeat angiography demonstrated improvement of the spasm, and the final radial angiograms demonstrated persistent improvement in caliber and regularity of the vessel. Each procedure was also completed via TRA with no periprocedural complications. CONCLUSIONS: Our modified Dotter technique was effective in bypassing areas of severe proximal flow-limiting RAS, obviating the need for access site conversion. Additional studies are warranted to understand the implication of the angioplasty-like effects seen within the radial artery after removal of the long radial sheaths.

The Genetic Basis of Adaptation following Plastic Changes in Coloration in a Novel Environment.

Phenotypic plasticity has been hypothesized to precede and facilitate adaptation to novel environments [1-8], but examples of plasticity preceding adaptation in wild populations are rare (but see [9, 10]). We studied a population of side-blotched lizards, Uta stansburiana, living on a lava flow that formed 22,500 years ago [11] to understand the origin of their novel melanic phenotype that makes them cryptic on the black lava. We found that lizards living on and off of the lava flow exhibited phenotypic plasticity in coloration but also appeared to have heritable differences in pigmentation. We sequenced the exomes of 104 individuals and identified two known regulators of melanin production, PREP and PRKAR1A, which had markedly increased levels of divergence between lizards living on and off the lava flow. The derived variants in PREP and PRKAR1A were only found in the lava population and were associated with increased pigmentation levels in an experimental cohort of hatchling lizards. Simulations suggest that the derived variants in the PREP and PRKAR1A genes arose recently and were under strong positive selection in the lava population. Overall, our results suggest that ancestral plasticity for coloration facilitated initial survival in the lava environment and was followed by genetic changes that modified the phenotype in the direction of the induced plastic response, possibly through de novo mutations. These observations provide a detailed example supporting the hypothesis that plasticity aids in the initial colonization of a novel habitat, with natural selection subsequently refining the phenotype with genetic adaptations to the new environment. VIDEO ABSTRACT.