Knowledge retention after focused cardiac ultrasound training: a prospective cohort pilot study

Background and objectives: Focused Cardiac Ultrasound (FoCUS) has proven instrumental in guiding anesthesiologists’ clinical decision-making process. Training residents to perform and interpret FoCUS is both feasible and effective. However, the degree of knowledge retention after FoCUS training remains a subject of debate. We sought to provide a description of our 4-week FoCUS curriculum, and to assess the knowledge retention among anesthesia residents at 6 months after FoCUS rotation. Methods: A prospective analysis involving eleven senior anesthesia residents was carried out. At end of FoCUS Rotation (EOR) participants completed a questionnaire (evaluating the number of scans completed and residents’ self-rated knowledge and comfort level with FoCUS), and a multiple-choice FoCUS exam comprised of written- and video-based questions. Six months later, participants completed a follow-up questionnaire and a similar exam. Self-rated knowledge and exam scores were compared at EOR and after 6 months. Spearman correlations were conducted to test the relationship between number of scans completed and exam scores, perceived knowledge and exam scores, and number of scans and perceived knowledge. Results: Mean exam scores (out of 50) were 44.1 at EOR and 43 at the 6-month follow-up. Residents had significantly higher perceived knowledge (out of 10) at EOR (8.0) than at the 6-month follow-up (5.5), p = 0.003. At the EOR, all trainees felt comfortable using FoCUS, and at 6 months 10/11 still felt comfortable. All the trainees had used FoCUS in their clinical practice after EOR, and the most cited reason for not using FoCUS more frequently was the lack of perceived clinical need. A strong and statistically significant (rho = 0.804, p = 0.005) correlation between number of scans completed during the FoCUS rotation and 6-month follow-up perceived knowledge was observed. Conclusion: Four weeks of intensive FoCUS training results in adequate knowledge acquisition and 6-month knowledge retention. Resumo: Justificativa e objetivos: A ultrassonografia cardíaca no local de atendimento (USCLA) provou ser importante para orientar o processo de tomada de decisão clínica dos anestesiologistas. Treinar os residentes para fazer e interpretar uma USCLA é viável e eficaz. No entanto, o grau de retenção do conhecimento após o treinamento permanece um assunto de debate. Procuramos fornecer uma descrição do currículo de quatro semanas do treinamento de USCLA e avaliar a retenção do conhecimento entre os residentes de anestesia seis meses após a rotação em USCLA. Métodos: Uma análise prospectiva foi realizada com 11 residentes seniores de anestesia. Ao final da rotação em USCLA, os participantes preencheram um questionário (avaliando o número de exames ultrassonográficos concluídos, o conhecimento adquirido e o nível de conforto dos residentes com a USCLA) e fizeram um exame de múltipla escolha para USCLA, composto por perguntas escritas e baseadas em vídeo. Seis meses depois, os participantes preencheram um questionário de acompanhamento e um exame similar. A autoavaliação do conhecimento e os escores do exame foram comparados no final da rotação e após seis meses. Correlações de Spearman foram usadas para testar a relação entre o número de exames concluídos e os escores dos exames, o conhecimento percebido, os escores dos exames, o número de exames e o conhecimento percebido. Resultados: Os escores médios dos exames (50) foram: 44,1 no final da rotação e 43 após seis meses. Os residentes tiveram conhecimento percebido significativamente maior (10) no final da rotação (8,0) que após seis meses (5,5), p = 0,003. No final da rotação, todos os residentes se sentiram confortáveis usando o aparelho de USCLA e, aos seis meses, 10/11 ainda se sentiam confortáveis. Todos os residentes haviam usado o USCLA em sua prática clínica após o final da rotação e a razão mais citada para não usar o USCLA com mais frequência foi a falta de necessidade clínica percebida. Uma correlação forte e estatisticamente significativa (rho = 0,804, p = 0,005) foi observada entre o número de exames realizados durante a rotação em USCLA e o conhecimento percebido em seis meses de seguimento. Conclusão: Quatro semanas de treinamento intensivo de USCLA resultaram em aquisição e retenção adequadas do conhecimento por seis meses. Keywords: POCUS, FoCUS, Knowledge retention, Education, Anesthesia, Palavras-chave: POCUS, USCLA, Retenção de conhecimento, Educação, Anestesi

Tissue-Specific Oncogenic Activity of KRASA146T

KRAS is the most frequently mutated oncogene. The incidence of specific KRAS alleles varies between cancers from different sites, but it is unclear whether allelic selection results from biological selection for specific mutant KRAS proteins. We used a cross-disciplinary approach to compare KRASG12D, a common mutant form, and KRASA146T, a mutant that occurs only in selected cancers. Biochemical and structural studies demonstrated that KRASA146T exhibits a marked extension of switch 1 away from the protein body and nucleotide binding site, which activates KRAS by promoting a high rate of intrinsic and guanine nucleotide exchange factor– induced nucleotide exchange. Using mice genetically engineered to express either allele, we found that KRASG12D and KRASA146T exhibit distinct tissue-specific effects on homeostasis that mirror mutational frequencies in human cancers. These tissue-specific phenotypes result from allele-specific signaling properties, demonstrating that context-dependent variations in signaling downstream of different KRAS mutants drive the KRAS mutational pattern seen in cancer. SIGNIFICANCE: Although epidemiologic and clinical studies have suggested allele-specific behaviors for KRAS, experimental evidence for allele-specific biological properties is limited. We combined structural biology, mass spectrometry, and mouse modeling to demonstrate that the selection for specific KRAS mutants in human cancers from different tissues is due to their distinct signaling properties.National Institutes of Health (Grant U01CA215798