The effects of catecholamines on longitudinal displacements and intramural shear strain of the arterial wall are unexplored. Therefore, the common carotid artery of five anaesthetized pigs was investigated using an in-house developed noninvasive ultrasonic technique. The study protocol included intravenous infusion of low-dose epinephrine (β-adrenoceptor activation), as well as intravenous boluses of norepinephrine (α-adrenoceptor activation). Further, the effects of β-blockade (metoprolol) were studied. There were significant positive correlations between pulse pressure and longitudinal displacement of the intima-media complex ( r = 0.72; P < 0.001), as well as between pulse pressure and intramural shear strain ( r = 0.48; P < 0.001). Following administration of norepinephrine, the longitudinal displacement of the intima-media complex and intramural shear strain profoundly increased (median 190%, range 102–296%, and median 141%, range 101–182%, respectively, compared with baseline), also when given during β-blockade (median 228%, range 133–266%, and median 158%, range 152–235%, respectively). During infusion of low-dose epinephrine, the longitudinal displacement of the intima-media complex and intramural shear strain decreased (median 88%, range 69–122%, and median 69%, range 47–117%, respectively, compared with baseline). In conclusion, the present study shows, for the first time, that the longitudinal displacement and intramural shear strain of the porcine carotid artery undergo profound changes in response to catecholamines. Increase in longitudinal displacements seems to be strongly related to α-adrenoceptor activation. Thus metoprolol is insufficient to counteract a profound increase in longitudinal displacement and intramural shear strain following a surge of norepinephrine.
Objective - To create a model for determining the optimum level of outpatient medical care and to determine this level.Design - Expert committees were established comprising one or two hospital physicians and two general practitioners who checked medical records for all outpatient visits to doctors made by a defined population during a defined period of time. the determination of optimum level was made blindly by each member of the expert committee.Setting and participants - the study comprised all visits to physicians during 10 weeks, in total more than 4000, made by the people in a Swedish community, of which 2084 were randomized.Results - Total agreement between the members of the committee was initially reached for 84% of the visits and, after a common discussion between the committee members, for 99%. A general practitioner was considered to be the optimum level of care for 76% of the patients in the total series, in the upper ages (above 80) for about 85%.Conclusion - This method seemed suitable for determining the optimum level of care in a population and may be of value when planning for an optimum health care service. Based on the results from our study it seems reasonable to assume that general practitioners whose training corresponds to that of Swedish ones are competent to treat about 75% of all consultations.
A 1-y retrospective study of problem oriented electronic patient records, for encounters concerning respiratory tract infection, was performed. The aim was to analyse the management of respiratory tract infections in primary health care in terms of diagnostic coding, tests and antibiotic treatment using data from electronic patient records. 12 primary health care centres with a registered population of 102,050 residents in 3 counties in southeast Sweden participated. Data were retrieved electronically from records of patient encounters concerning respiratory tract infections. The data were: patient age and gender, date of contact, diagnostic code, CRP and GABHS tests and results, as well as antibiotic prescriptions. In a total of 19,965 encounters, the most frequent diagnoses were common cold (40%), acute tonsillitis (18%), and acute bronchitis (15%). A total of 4445 GABHS tests (in 22% of encounters) and 6141 CRP tests (31%) were performed, and both tests were done in 1910 encounters (10%). A total of 7934 antibiotic prescriptions were registered. The proportion of patients tested and prescribed an antibiotic varied greatly between centres. We found an excessive, and much varying, use of rapid tests in encounters for respiratory tract infections. Data retrieval from electronic patient record systems was a feasible method to study the use of laboratory tests in relation to pharmacological treatment.