Three Zone Scanning Protocol For Lung Ultrasound: An Anatomical Basis.

Lung ultrasound is rapidly gaining popularity based on point of care ease of use, diagnostic fidelity and lack of ionising radiation. This was particularly notable at the beginning of the COVID-19 pandemic, where concerns of contamination of the x-ray department led to a reluctance to order frequent chest x-rays. Early COVID-19 lung involvement is of a bronchopneumonia, and patches of consolidation adjacent to the chest wall were easily detectable by ultrasound. A large number of proposed scanning protocols were advocated and are often complex and largely based on traditional stethoscope examination or access points on the chest wall rather than the underlying lung anatomy. A surgical understanding of lung anatomy and related surface anatomy has led us to develop a simplified three zone scanning protocol in 2013. The anterior zone corresponds to the upper lobe, and the posterior zone is divided between upper lobe and lower lobe. The relationship between lung lobes and the surface of the chest wall provides the anatomical basis for a simple three scanning zone lung ultrasound protocol.

Point-of-care ultrasound for deep venous thrombosis of the lower limb.

The incidence and morbidity of deep venous thrombosis (DVT) and pulmonary embolus are high. Although efforts to increase screening for DVT have been recommended, this is limited by resources. Venous duplex ultrasound has replaced venography as the first-line investigation of choice for DVT, increasing availability and reducing patient exposure to radiation and intravenous contrast. Furthermore, an abbreviated ultrasound where DVT is inferred from incomplete venous compressibility has an equivalent accuracy to venous duplex, requiring less time and training enabling its widespread use by emergency, critical care and anaesthesia clinicians. In this review, the evolution and method of lower limb venous compression ultrasound is described along with evidence for its use in patients at high risk for DVT in these clinical settings.

Effect of a clinical flowchart incorporating Wells score, PERC rule and age-adjusted D-dimer on pulmonary embolism diagnosis, scan rates and diagnostic yield.

OBJECTIVE: To assess the association between the use of a flowchart incorporating Wells score, PERC rule and age-adjusted D-dimer and subsequent imaging and yield rates of computed tomography pulmonary angiogram and nuclear medicine ventilation perfusion scans being ordered in the ED for the assessment of pulmonary embolism. METHODS: A flowchart governing ED pulmonary embolism investigation was introduced across three EDs in Melbourne, Australia for a 12 month period. Comparison of pulmonary embolism imaging rates and yield with the preceding 12 months was performed. RESULTS: A total of 1815 pre-implementation scans were performed compared with 1116 scans post-implementation. Because of growth in patient attendances over this time, this equated to an imaging rate of 14.5 per 1000 presentations pre-implementation and 8.6 per 1000 presentations post-implementation (P < 0.001). Overall pulmonary embolism imaging yield rates rose from 9.9% to 16.5% (P < 0.001). A total of 179 pre-implementation pulmonary embolisms were identified, with an incidence of 1.4 per 1000 presentations. This compared to 184 pulmonary embolisms post-implementation, with an incidence of 1.4 per 1000 presentations (P = 0.994). CONCLUSION: The introduction of a clinical flowchart incorporating Wells score, PERC rule and age-adjusted D-dimer was associated with an increase in ED computed tomography pulmonary angiogram and nuclear medicine ventilation perfusion yield rate from 9.9% to 16.5% across the three enrolment hospitals when investigating possible pulmonary embolism. This corresponded to a 40% relative reduction in pulmonary embolism imaging. Diagnosis rates remained unchanged and no cases of missed pulmonary embolism attributable to the flowchart were identified.