Prehospital assessment of patients with abdominal pain triaged to self-care at home: an observation study.

BACKGROUND: Patients who call for emergency medical services (EMS) due to abdominal pain suffer from a broad spectrum of diseases, some of which are time sensitive. As a result of the introduction of the concept of 'optimal level of care', some patients with abdominal pain are triaged to other levels of care than in an emergency department (ED). We hypothesised that it could be challenging in a patient safety perspective. AIM: This study aims to describe consecutive patients who call for EMS due to abdominal pain and are triaged to self-care by EMS clinicians. METHODS: This was an observational study performed in an EMS organisation in Western Sweden during 2020. The triage tool Rapid Emergency Triage and Treatment System (RETTS), which included Emergency Signs and Symptom (ESS) codes, was used to find medical records where patients with abdominal pain have been triaged to self-care and 194 patients was included in the study. RESULTS: Of total 48,311 ambulance missions, A total of 1747 patients were labelled with ESS code six (abdominal pain), including 223 (12.8%) who were given the code for self-care and 194 who were further assessed by the research group. Of these patients, 32 (16.3%) had a return visit within 96 hours due to the same symptoms and 11 (5.6%) were hospitalised. In six of these patients, the EMS triage was evaluated retrospectively and assessed as inappropriate. These patients had a final diagnosis of ruptured abdominal aneurysm (n = 1), acute appendicitis with peritonitis (n = 2) and acute pancreatitis (n = 3). All these patients required extensive evaluation and different treatments, including acute surgery, antibiotics and fluid therapy. CONCLUSION: Amongst the 1747 patients assessed by EMS due to abdominal pain, 223 (12.8%) were triaged to self-care. Of the 194 patients who were further assessed, 16.3% required a return visit to the ED within 96 hours and 5.6% were hospitalised. Six patients had obvious time-sensitive conditions. Our study highlights the difficulties in the early assessment of abdominal pain and the requirement for an accurate decision support tool.

Color and shape measurement with a three-color photometric stereo system.

The purpose of our research has been to develop a system for measurement of microtopography based on the photometric stereo principle. In a previous system, in which we used two illumination directions facing each other, we had difficulties in detecting topography variations perpendicular to the illumination direction. With the new measurement system we avoid this problem by use of three colored and two white illumination modules. The integration problem that occurred when the gradient was known in more than one direction was solved by use of weight functions in the spatial-frequency domain. The results show that true three-dimensional surface height functions can be obtained with the new method. This is a significant improvement from the two-source system, in which we could make only estimates of profiles perpendicular to the illumination direction. To quantitatively evaluate the new measurement system, the results were compared with measurements of a mechanical stylus instrument. Comparisons between mechanical and optical measurements show a coefficient of determination r2 between 0.71 and 0.81 for the new system and r2 between 0.57 and 0.88 for the two-source system.