ABSTRACT
BACKGROUND: The aim of this study is to assess the accuracy of a Fast Doppler protocol for the examination of an injured lower limb, namely 2-Point Fast Doppler (2PFD), in order to rapidly triage arterial lesions after penetrating trauma. METHODS: The presence of flow and the aspects of the Doppler waveform of the dorsalis pedis artery (DPA) and posterior tibial artery (PTA) of the injured lower limb (2PFD) were evaluated immediately before the execution of a standardized Color Duplex Doppler (SD) evaluation in 149 limbs of 140 patients with gunshot penetrating injuries. We considered 2PFD normal exams as the ones with triphasic patterns in both the DPA and PTA, and 2PFD pathologic exams as the ones with absent, biphasic, or monophasic flow patterns in the DPA and/or PTA. 2PFD data were then analyzed to assess accuracy variables, using SD results as matching test reference. According to the trauma center standard protocols, SD positive cases underwent also angiography and surgical exploration, whose findings were used to further match the 2PFD specificity. RESULTS: The 2PFD protocol showed a sensitivity of 100%, and a specificity of 100% compared with the SD, in the diagnostic workup of arterial injuries of the lower limbs after penetrating trauma. Furthermore, all the pathologic cases that resulted in all true positives (TP), compared with SD, were confirmed as TP also when matched with the angiography evaluation results. CONCLUSIONS: The 2PFD protocol can rapidly identify arterial flow and differentiate between normal and pathologic spectral Doppler analyses in distal arteries. The presence of the normal triphasic flows in DPA and PTA is as sensitive as the standardized Color Doppler Duplex assessment of the entire limb in ruling out arterial lesions in lower-limb penetrating trauma. The absence of flow or the presence of a biphasic or monophasic pathologic flow in DPA and PTA is pathologic and should be always followed by further investigation. 2PFD is faster and easier to perform compared with the SD approach. It could become a new first-line screening technique, both in pre-hospital and hospital critical scenarios, particularly in contexts where advanced diagnostic performance is limited by time concerns or scarce resources.
ABSTRACT
BACKGROUND: Point of care ultrasound (POCUS) is a useful diagnostic tool in medicine. POCUS provides an easy and reproducible method of diagnosis where conventional radiologic studies are unavailable. Telemedicine is also a great means of communication between educators and students throughout the world. HYPOTHESIS: Implementing POCUS with didactics and hands-on training, using portable ultrasound devices followed by telecommunication training, will impact the differential diagnosis and patient management in a rural community outside the United States. MATERIALS AND METHODS: This is an observational prospective study implementing POCUS in Las Salinas, a small village in rural western Nicaragua. Ultrasound was used to confirm a diagnosis based on clinical exam, or uncover a new, previously unknown diagnosis. The primary endpoint was a change in patient management. International sonographic instructors conducted didactic and practical training of local practitioners in POCUS, subsequently followed by remote guidance and telecommunication for 3 months. RESULTS: A total of 132 patients underwent ultrasound examination. The most common presentation was for a prenatal exam (23.5 %), followed by abdominal pain (17 %). Of the 132 patients, 69 (52 %) were found to have a new diagnosis. Excluding pregnancy, 67 patients of 101 (66 %) were found to have a new diagnosis. A change in management occurred in a total of 64 (48 %) patients, and 62 (61 %) after excluding pregnancy. CONCLUSION: Implementing POCUS in rural Nicaragua led to a change in management in about half of the patients examined. With the appropriate training of clinicians, POCUS combined with telemedicine can positively impact patient care.
ABSTRACT
BACKGROUND: One of the major pitfalls associated with use of isolated adult islets of Langerhans' cells is their minimal mitotic capacity. Consequently, maintenance of a steady viable islet cell mass is very difficult. To explore how to enhance beta-cell mitogenesis, we have examined the effects of venom fractions extracted from a Brazilian scorpion on morphologic and functional beta-cell patterns. The venom was previously known to induce nesidioblastosis-like effects with chronic hypoglycemia and pancreatitis in animal models. METHODS: Venom fractions purified from Tityus bahiensis were incubated with batches of isolated rat islets, while a morphologic examination, glucose-stimulated insulin release, insulin content, and insulin messenger ribonucleic acid (mRNA) were carried out early during incubation. On fixation and double fluorescence immunolabeling (rhodamine for anti-insulin monoclonal antibodies; fluorescein for anti-5-bromodeoxyuridine), the preparations were imaged by confocal laser microscopy (CLM) for morphometric quantification of the mitoses. Insulin recovery and mRNA were also assessed at 21 days of culture. RESULTS: Under CLM examination, the beta-cell mitotic rate significantly rose from 1 to 12.8% for the venom-exposed islets. At day 7, insulin release and content were significantly lower for the venom-exposed than the control islets. However, at day 21 of culture, insulin release in response to static incubation with glucose and insulin mRNA from the venom-exposed islets was higher than controls (p < .05). CONCLUSIONS: Incubation with the scorpion venom induced a rapid and significant increase in the beta-cell proliferation not associated with a short-term increase in insulin secretion. The latter fully resumed and overcame controls later in culture, possibly after completion of the beta-cell expansion process.