Blood cell differential count discretisation modelling to predict survival in adults reporting to the emergency room: a retrospective cohort study.

OBJECTIVES: To assess the survival predictivity of baseline blood cell differential count (BCDC), discretised according to two different methods, in adults visiting an emergency room (ER) for illness or trauma over 1 year. DESIGN: Retrospective cohort study of hospital records. SETTING: Tertiary care public hospital in northern Italy. PARTICIPANTS: 11 052 patients aged >18 years, consecutively admitted to the ER in 1 year, and for whom BCDC collection was indicated by ER medical staff at first presentation. PRIMARY OUTCOME: Survival was the referral outcome for explorative model development. Automated BCDC analysis at baseline assessed haemoglobin, mean cell volume (MCV), red cell distribution width (RDW), platelet distribution width (PDW), platelet haematocrit (PCT), absolute red blood cells, white blood cells, neutrophils, lymphocytes, monocytes, eosinophils, basophils and platelets. Discretisation cut-offs were defined by benchmark and tailored methods. Benchmark cut-offs were stated based on laboratory reference values (Clinical and Laboratory Standards Institute). Tailored cut-offs for linear, sigmoid-shaped and U-shaped distributed variables were discretised by maximally selected rank statistics and by optimal-equal HR, respectively. Explanatory variables (age, gender, ER admission during SARS-CoV2 surges and in-hospital admission) were analysed using Cox multivariable regression. Receiver operating curves were drawn by summing the Cox-significant variables for each method. RESULTS: Of 11 052 patients (median age 67 years, IQR 51-81, 48% female), 59% (n=6489) were discharged and 41% (n=4563) were admitted to the hospital. After a 306-day median follow-up (IQR 208-417 days), 9455 (86%) patients were alive and 1597 (14%) deceased. Increased HRs were associated with age >73 years (HR=4.6, 95% CI=4.0 to 5.2), in-hospital admission (HR=2.2, 95% CI=1.9 to 2.4), ER admission during SARS-CoV2 surges (Wave I: HR=1.7, 95% CI=1.5 to 1.9; Wave II: HR=1.2, 95% CI=1.0 to 1.3). Gender, haemoglobin, MCV, RDW, PDW, neutrophils, lymphocytes and eosinophil counts were significant overall. Benchmark-BCDC model included basophils and platelet count (area under the ROC (AUROC) 0.74). Tailored-BCDC model included monocyte counts and PCT (AUROC 0.79). CONCLUSIONS: Baseline discretised BCDC provides meaningful insight regarding ER patients' survival.

Lung-ultrasound objective structured assessment of technical skills (LUS-OSAUS): utility in the assessment of lung-ultrasound trained medical undergraduates.

PURPOSE: Recently, some attempts have been made to integrate lung ultrasound (LUS) teaching into medical curricula. However, current education studies of LUS are extremely heterogeneous due to the lack of evidence-based guidelines on LUS education. In particular, the assessment of competencies is poorly standardized and mostly relies on non-validated scales. A new validated tool, the objective structured assessment of lung ultrasound skills (LUS-OSAUS), has the potential to overcome these limitations. Therefore, we adopted the LUS-OSAUS tool to assess the competencies of a group of LUS-trained undergraduates. Existing no prior practical applications of the LUS-OSAUS, our aim was to investigate the practical utility of this tool and its applicability in the evaluation of US-trained medical students. METHODS: Eight undergraduates (two males, six females) were enrolled on a voluntary basis to receive a theoretical and practical training in LUS. Once completed their training, each student performed an LUS examination on a different patient hospitalized for respiratory symptoms. The same eight patients were also scanned by a senior resident in emergency medicine for a comparison with students' results. Students and the senior resident were tested by an examiner using the LUS-OSAUS tool. We compared the scores obtained by operators in all areas of competence of the LUS-OSAUS, the total scores, and the time needed to complete the sonographic task. RESULTS: Median students' score in the single items of the scale was significantly lower than the ones obtained by the senior resident (4.0 [3.3-5.0] vs. 5.0 [5.0-5.0]; p < 0.0001). Students scored significantly lower than the senior resident in each item, except for B-line identification, choice of the correct transducer, and suggested focused questions. Median total score was also lower for students compared to the senior resident (70.5 [61.0-74.8] vs. 84.0 [83.5-84.3] (p = 0.0116). Median time required to complete the examination was significantly higher for students (14.1 [12.8-16.1] vs. 4.7 [3.9-5.2] min, p = 0.0117). CONCLUSIONS: The LUS-OSAUS tool allowed for a standardized and comprehensive assessment of student's competencies in lung ultrasound, and helped to discriminate their level of expertise from that of a more experienced operator. The scale also specifically tests the theoretical knowledge of trainees, thus making redundant the use of questionnaires designed for this purpose.