Workload of on-call emergency room neurologists in a Spanish tertiary care centre. A one-year prospective study.

INTRODUCTION: Population ageing, the rising demand for healthcare, and the establishment of acute stroke treatment programs have given rise to increases in the number and complexity of neurological emergency cases. Nevertheless, many centres in Spain still lack on-call emergency neurologists. METHODS: We conducted a retrospective study to describe the role of on-call neurologists at Hospital General Universitario Gregorio Marañón, a tertiary care centre in Madrid, Spain. Sociodemographic characteristics, most common pathologies, diagnostic tests, and destination of the patients attended were recorded daily using a computer database. Results were compared with the general care data from the emergency department. RESULTS: The team attended 3234 patients (3.48% of the emergency department total). The mean number of patients seen per day was 11.15. The most frequent pathologies were stroke (34%), epilepsy (16%) and headache (8%). The mean stay in the emergency department was 7.17 hours. Hospital admission rate was 40% (7.38% of emergency hospital admissions). The main destinations for admitted patients were the stroke unit (39.5%) and the neurology department (33%). Endovascular or thrombolytic therapies were performed on 76 occasions. Doctors attended 70% of the patients during on-call hours. CONCLUSIONS: Emergency neurological care is varied, complex, and frequently necessary. Neurological cases account for a sizeable percentage of both patient visits to the emergency room and the total number of emergency admissions. The current data confirm that on-call neurologists available on a 24-hour basis are needed in emergency departments.

Thermoluminescent dosimeters for low dose X-ray measurements.

The response of TLD-100, CaSO4:Dy and LiF:Mg,Cu,P for a range of X-ray low dose was measured. For calibration, the TLDs were arranged at the center of the X-ray field. The dose output of the X-ray machine was determined using an ACCU-Gold. All dosimeters were exposed at the available air kerma values of 14.69 mGy within a field 10×10 cm(2) at 80 cm of SSD. Results of LiF:Mg,Cu,P X-ray irradiated showed 4.8 times higher sensitivity than TLD-100. Meanwhile, TL response of CaSO4:Dy exposed at the same dose was 5.6 time higher than TLD-100. Experimental results show for low dose X-ray measurements a better linearity for LiF:Mg,Cu,P compared with that of TLD-100. CaSO4:Dy showed a linearity from 0.1 to 60 mGy.

Thermoluminescent characteristics of LiF:Mg, Cu, P and CaSO4:Dy for low dose measurement.

Thermoluminescence (TL) characteristics for LiF:Mg, Cu, P, and CaSO4:Dy under the homogeneous field of X-ray beams of diagnostic irradiation and its verification using thermoluminescence dosimetry are presented. The irradiation were performed utilizing a conventional X-ray equipment installed at the Hospital Juárez Norte of México. Different thermoluminescence characteristics of two material were studied, such as batch homogeneity, glow curve, linearity, detection threshold, reproducibility, relative sensitivity and fading. Materials were calibrated in terms of absorbed dose to the standard calibration distance and they were positioned in a generic phantom. The dose analysis, verification and comparison with the measurements obtained by the TLD-100 were performed. Results indicate that the dosimetric peak appears at 202°C and 277.5°C for LiF:Mg, Cu, P and CaSO4:Dy, respectively. TL response as a function of X-ray dose showed a linearity behavior in the very low dose range for all materials. However, the TLD-100 is not accurate for measurements below 4mGy. CaSO4:Dy is 80% more sensitive than TLD-100 and it show the lowest detection threshold, whereas LiF:Mg, Cu, P is 60% more sensitive than TLD-100. All materials showed very good repeatability. Fading for a period of one month at room temperature showed low fading LiF:Mg, Cu, P, medium and high for TLD-100 and CaSO4:Dy. The results suggest that CaSO4:Dy and LiF:Mg, Cu, P are suitable for measurements at low doses used in radiodiagnostic.