Page 207 - Ultrasonography in Prehospital and Emergency Medicine - Rein Ketelaars

Summary and discussion
In this thesis, we focused on several aspects of emergency ultrasonography. We explored the literature, equipment and a selection of transducers. We evaluated its implementation and utility in the emergency department, the prehospital environment, and in future prehospital applications.
Prehospital and emergency ultrasonography is still very much in development. Partly, this is because the technology of ultrasound equipment is continuously improving. Weight, size, and costs are decreasing and image quality is improving. Therefore, general interest is grow- ing, resulting in an increase in manufacturers and availability of (affordable) ultrasound devices on the market. Because of the increased availability, a rising number of nonradiol- ogist healthcare providers are embracing ultrasonography for a growing set of indications. Similarly, the body of evidence in the literature is expanding.
In Part I of this thesis, background information on prehospital emergency ultrasonography and the technology was provided by means of a review of the literature and research on the equipment used.
In Chapter 2, a narrative review of the literature on prehospital ultrasonography was pre- sented. In addition to the paper that was published in the Critical Ultrasound Journal the full search query was added as an appendix. We included every paper that provided addi- tional information to create a comprehensive overview of all aspects of prehospital ultraso- nography that are discussed in the literature. We discussed current and future applications of prehospital ultrasonography, both for diagnostic and therapeutic use. Additionally, we highlighted some applications of ultrasonography in the emergency department and in other settings such as clinical, military, and wilderness medicine, that seem suitable for general prehospital use. Some of the pitfalls of prehospital ultrasonography have been discussed such as the time investment of ultrasound examinations that not always will pay off, and the fact that the diagnostic accuracy of prehospital ultrasonography (PHUS) may be disappointing in some cases. Its accuracy depends to a large extent on the level of training and experience of the PHUS operator.
Since PHUS was introduced in the Nijmegen helicopter emergency medical service (HEMS), both a phased-array cardiac transducer and a linear-array transducer have been available. The phased-array transducer was used by most HEMS physicians as their first choice. This all-round transducer may be used for the extended focused assessment with sonography for trauma (eFAST) and prehospital rapid echo-evaluation program (PREP) examinations. Al-
Summary, discussion, and future perspective 205
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