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BACKGROUND: Pre-hospital emergency nurse (PEN) specialists are faced with patients presenting with non-specific chief complaints (NSC) to the emergency medical service (EMS) on a daily basis. These patients are often elderly and one in three has a serious condition and their acuity is not recognized. OBJECTIVE: The aim of the current study was to explore PEN specialists' experiences in caring for patients presenting with non-specific chief complaints. DESIGN: A qualitative study design with eleven individual interviews of PENs, between 2018 and 2020. Qualitative content analysis was used. RESULTS: The analyses generated three categories including subcategories. The categories were "Unexplained suffering". "Systematic approach and experience enhances medical safety". "Organizational processes can be optimized". The relation between the categories compiled as ́In-depth systematic assessment is perceived to reduce suffering and increases patient safetý. CONCLUSION: The PENs experiences in caring for patients presenting with non-specific chief complaints show that an in-depth systematic assessment may lead to a meaningful caring encounter which enables the identification of the cause of the chief complaint. Experience and a systematic approach were considered as essential to enhance medical safety. This could be strengthened through feedback on the nurse's care provided by care managers and employers. To optimize organizational processes, the development of the opportunity to convey the patient to different levels of care can be an important component.

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BACKGROUND: An incident command structure is commonly used to manage responses to major incidents. In the hospital incident command structure, the medical officer in charge (MOC) is in a key position. The decision-making process is essential to effective management, but little is known about which factors influence the process. Therefore, the current study aimed to describe factors influencing decision-making of MOCs. METHODS: A conventional content analysis was conducted based on 16 individual interviews with medical doctors who had been deployed as MOCs at Swedish hospitals during major incidents. RESULTS: The results showed that the decision-making and re-evaluation process was a comprehensive analysis influenced by three categories of factors: event factors, including consequences from the type of event, levels of uncertainty and the circumstances; organizational factors, including the doctor's role, information management and the response to the event; and personal factors, such as competence, personality and mental preparedness. CONCLUSIONS: Reliable and timely information management structure enabling the gathering and analysis of essential information, a clear command structure and appropriate personal qualities were essential and contributed to successful MOCs decision making in major incidents.

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BACKGROUND: It is a challenge to dispatch Emergency medical Services (EMS) appropriately with limited resources and maintaining patient safety; this requires accurate dispatching systems. The objective of the current systematic review was to examine the evidence, according to GRADE, for medical dispatching systems to accurately dispatch EMS according to level of acuity and in recognition of specific conditions. A systematic search was performed trough PubMed, Web of Science, Embase (free text in all fields), Centre for Reviews and Dissemination (CRD), and Cochrane Central Register of Controlled Trials up to 16th of May, 2017. A combination of keywords and Medical Subject Heading (MeSH) terms relevant to "emergency medical dispatch criteria" were used, to search for articles published between 2012 and 2017. Publications were included according to the inclusion/exclusion criteria using the Systematic Reviews and Meta-Analyses (PRISMA) protocol. Level of evidence was evaluated in accordance with Grading of Recommendations Assessment, Development and Evaluation (GRADE). Articles included were those that provided evidence for at least one of the measures of dispatch system accuracy; i.e. sensitivity, specificity, positive and negative predictive and/or over- and under-triage. The search identified 1445 articles. After the removal of duplicates, 382 titles were reviewed for relevance and an additional 359 articles were excluded based on manuscript title and abstract. An additional five articles were excluded after review of the full text versions of the remaining articles. The current review included 18 publications which all were based on primary research. CONCLUSIONS: The 18 articles addressed the identification of cardiac arrest, stroke, medical priority and major trauma using different dispatching systems. The results of the current review show that there is a very low to low overall level of evidence for the accuracy of medical dispatching systems. We suggest that it is necessary to create a consensus on common standards for reporting before consensus can be reached for the level of accuracy in medical dispatching systems.

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BACKGROUND: Studies suggest that the Ser49Gly and Arg389Gly polymorphisms in the beta1-adrenergic receptor might be of functional importance for the cardiovascular system. Both have been associated with altered receptor activity in vitro, and with hypertension and cardiac failure in vivo. HYPOTHESIS: The aim of this study was to test whether these polymorphisms were associated with the change in heart rate or blood pressure in patients with essential hypertension and left ventricular (LV) hypertrophy treated with the beta1-adrenergic receptor blocker atenolol. METHODS: Blood pressure and heart rate were measured in 101 hypertensive patients with echocardiographically verified LV hypertrophy, randomized in a double-blind study to treatment with either the beta1-adrenergic receptor blocker atenolol or the angiotensin II type I receptor antagonist irbesartan. Changes in blood pressure and heart rate were evaluated after 12 weeks. Beta1-adrenergic receptor genotyping was performed using polymerase chain reaction and restriction fragment length polymorphism. RESULTS: We found no significant associations between the changes in the measured variables and either of the two polymorphisms. However, carriers of the 49Gly allele showed a tendency toward a greater reduction in heart rate compared with patients with the Ser/Ser49 genotype (p = 0.06). CONCLUSIONS: The Ser49Gly and Arg389Gly beta1-adrenergic receptor polymorphisms do not seem to exert a major effect on the changes in heart rate and blood pressure during 12 weeks of treatment with atenolol in patients with essential hypertension and LV hypertrophy.

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BACKGROUND: Studies suggest that endothelin-1 contributes to the pathogenesis of hypertension. A G5665T gene polymorphism of preproendothelin-1 has been shown to be associated with higher blood pressure in overweight patients. No study has yet determined the effect of this polymorphism on the change in blood pressure during antihypertensive treatment. HYPOTHESIS: This study aimed to determine this effect in hypertensive patients with left ventricular (LV) hypertrophy during antihypertensive treatment with either irbesartan or atenolol. METHODS: We determined the preproendothelin-1 genotype using minisequencing in 102 patients with essential hypertension and LV hypertrophy verified by echocardiography, randomized in a double-blind fashion to treatment with either the AT1-receptor antagonist irbesartan or the beta1-adrenoceptor antagonist atenolol. RESULTS: The change in systolic blood pressure (SBP) after 12 weeks of treatment was related to the preproendothelin-1 genotype in men; after adjustment for potential covariates (age, blood pressure, and LV mass index at study entry, dose of irbesartan/atenolol, and type of treatment), those carrying the T-allele responded on average with a more than two-fold greater reduction than those with the G/G genotype (-21.9 mmHg 13.9] vs. -8.9 [2.3], p = 0.007). No significant differences in blood pressure change between G/G and carriers of the T-allele were seen among women. CONCLUSIONS: Our finding suggests a gender-specific relationship between the G5665T preproendothelin-1 polymorphism and change in SBP in response to antihypertensive treatment with irbesartan or atenolol, suggesting the endothelin pathway to be a common mechanism included in the hypertensive action of the drugs.

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Coronary heart disease is the leading cause of death in the Western world. Approximately half of all the people who have their 1st heart attack and 2/3 of those with their first stroke have high blood pressure levels. Hypertension affects approximately 25% of the adult population. By treating hypertension and risk factors that contribute to cardiovascular disease both mortality and morbidity can be reduced. Many drugs have proven to be effective in treating hypertension, although the individual patient's response to antihypertensive treatment varies over a wide range and cannot be predicted with methods used today. Between 30-60% of the blood pressure variation is determined by genetic factors. Also the variation in drug response is in part heritable, which defines pharmacogenetics. This review gives a general background to pharmacogenetics and its potential usage. In addition, results from recent pharmacogenetics studies on the antihypertensive effect of the angiotensin II type 1 receptor antagonist irbesartan are presented.

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OBJECTIVES: To determine whether polymorphisms in the renin-angiotensin system can predict blood pressure-lowering response to antihypertensive treatment; more specifically, in response to treatment with irbesartan or atenolol. DESIGN AND METHODS: Eighty-six patients with hypertension were randomized to double-blind treatment with either the angiotensin II type 1 receptor antagonist irbesartan or the beta1 adrenergic receptor blocker atenolol and followed for 3 months. We analysed angiotensinogen T174M and M235T, angiotensin converting enzyme (ACE) I/D and angiotensin II type 1 receptor A1166C polymorphisms and related them to blood pressure reduction. RESULTS: The mean reductions in blood pressure were similar for both treatments. In the irbesartan group, individuals homozygous for the ACE gene I allele showed a greater reduction in diastolic blood pressure, exceeding those with the D allele (-18 +/- 11 SD versus -7 +/- 10 mmHg, P = 0.0096). This was not the case during treatment with atenolol, and the interaction term between type of treatment and ACE II genotype was significant (P = 0.0176). The angiotensinogen and angiotensin II type 1 receptor polymorhisms were not related to the response to treatment. CONCLUSIONS: ACE genotyping predicted the blood pressure-lowering response to antihypertensive treatment with irbesartan but not atenolol. Thus, specific genotypes might predict the response to specific antihypertensive treatment.

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BACKGROUND: Our aim was to test the hypothesis that genes encoding components in the renin-angiotensin system influence endothelial vasodilatory function. METHODS: In 59 apparently healthy, normotensive individuals, endothelium-dependent vasodilation (EDV) and endothelial-independent vasodilation (EIDV) was evaluated by infusing metacholine and sodium nitroprusside into the brachial artery. Forearm blood flow was measured by venous occlusion plethysmography. The ACE insertion (I)/deletion (D) polymorphism, the T174M and M235T angiotensinogen restriction fragments length polymorphisms, the angiotensin II receptor type 1 (AT1R) A1166C, and the aldosterone synthase gene (CYP11B2) C-344T polymorphisms were analysed. RESULTS: When analysing the ACE, the two angiotensinogen and the aldosterone synthase CYP11B2 genotypes independently, no significant association with endothelial vasodilatory function was found. However, a significant reduction in endothelium-dependent vasodilation was observed in the subjects (n=9) with the ACE D allele and the angiotensinogen T174M genotype (P<0.05). Subjects with the AT1R genotype AC showed a reduction in both EDV (P=0.05) and EIDV (P=0.04) when compared with those with the AA genotype. CONCLUSIONS: The subjects with the ACE D allele in combination with the angiotensinogen T174M genotype are associated with a reduced EDV. This together with the observation that the AC AT1R genotype is associated with a reduction in both EDV and EIDV, supports the hypothesis that endothelial vasodilatory function is influenced by genes in the renin-angiotensinogen system.

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BACKGROUND: Myopia is an important public health problem because it is common and is associated with increased risk for chorioretinal degeneration, retinal detachment, and other vision- threatening abnormalities. In animals, ocular elongation and myopia progression can be lessened with atropine treatment. This study provides information about progression of myopia and atropine therapy for myopia in humans. METHODS: A total of 214 residents of Olmsted County, Minnesota (118 girls and 96 boys, median age, 11 years; range 6 to 15 years) received atropine for myopia from 1967 through 1974. Control subjects were matched by age, sex, refractive error, and date of baseline examination to 194 of those receiving atropine. Duration of treatment with atropine ranged from 18 weeks to 11.5 years (median 3.5 years). RESULTS: Median followup from initial to last refraction in the atropine group (11.7 years) was similar to that in the control group (12.4 years). Photophobia and blurred vision were frequently reported, but no serious adverse effects were associated with atropine therapy. Mean myopia progression during atropine treatment adjusted for age and refractive error (0.05 diopters per year) was significantly less than that among control subjects (0.36 diopters per year)(P<.001). Final refractions standardized to the age of 20 years showed a greater mean level of myopia in the control group (3.78 diopters) than in the atropine group (2.79 diopters) (P<.001). CONCLUSIONS: The data support the view that atropine therapy is associated with decreased progression of myopia and that beneficial effects remain after treatment has been discontinued.

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Amyotrophic lateral sclerosis (ALS), parkinsonism and/or dementia are highly prevalent among the Chamorro population of Guam. The incidence of Guamanian ALS has markedly declined in recent years, but these incidence figures may reflect underascertainment of subclinical disease. Guamanian Chamorro patients have not been systematically studied using modern clinical neurophysiological techniques. Electromyography (EMG: needle exam and nerve conduction studies) was used to study 29 patients with the major subtypes of Guamanian neurodegenerative disease, as well as 11 neurologically normal Guamanian Chamorro subjects. Central conduction was assessed by somatosensory evoked potentials (SEP's) in 16 patients. EMG evidence of peripheral neuropathy, (often subclinical) was found in 45% of Guamanian patients but no Chamorro control subjects. Diabetes mellitus, which is highly prevalent in this population, was present in some, but not all of these cases. Clinically unsuspected motor neuron disease was identified by EMG in only one of the 23 Guamanian patients with parkinsonism and/or dementia and in none of the 11 Chamorro control subjects. Two of seven patients with the clinical phenotype of Guamanian ALS had a more benign EMG pattern on the needle electrode exam with absence of fibrillation and fasciculation potentials. Three of 16 patients (all with parkinsonism and dementia) had mildly abnormal tibial SEP's. No patient had EMG evidence of myopathy or a defect of neuromuscular transmission. We conclude: (1) peripheral neuropathy may be a manifestation of Guamanian neurodegenerative disease; (2) the declining prevalence of ALS on Guam is not associated with the development of a subclinical form of motor neuron disease; (3) the substantial overlap of Guamanian ALS with parkinsonism-dementia reported in prior decades is no longer apparent; (4) abnormal central conduction, as assessed by tibial SEP's, is present in some patients with Guamanian parkinsonism-dementia.

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Controversy continues as to whether traumatic brain injury is a risk factor for Alzheimer's disease. The authors examined a related hypothesis that among persons with traumatic brain injury who develop Alzheimer's disease, time to onset of the disease is reduced. They used data on all documented episodes of traumatic brain injury that occurred from 1935 to 1984 among Olmsted County, Minnesota, residents. Community-based medical records were used to follow traumatic brain injury cases who were aged 40 years or older at last contact prior to June 1, 1988, for Alzheimer's disease until last contact, death, or June 1, 1988. The test of the hypothesis was restricted to those cases who developed Alzheimer's disease. The expected time to onset of Alzheimer's disease was derived from a life table constructed by using age-of-onset distributions within sex groups for a previously identified cohort of Rochester, Minnesota, Alzheimer's disease incidence cases without a history of head trauma. The authors found that of the 1,283 traumatic brain injury cases followed, 31 developed Alzheimer's disease, a number similar to that expected (standardized incidence ratio = 1.2, 95% confidence interval 0.8-1.7). However, the observed time from traumatic brain injury to Alzheimer's disease was less than the expected time to onset of Alzheimer's disease (median = 10 vs. 18 years, p = 0.015). The results suggest that traumatic brain injury reduces the time to onset of Alzheimer's disease among persons at risk of developing the disease.

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OBJECTIVES: To assess whether olfactory deficits are present in the general Guamanian Chamorro population and to evaluate olfaction in each of the four neurodegenerative disease syndromes of Guam: ALS, pure parkinsonism, pure dementia, and the combined parkinsonism-dementia complex (PDC). BACKGROUND: Olfactory dysfunction was previously reported in patients with PDC of Guam. METHODS: We developed a culturally adjusted olfactory test battery, derived from the original University of Pennsylvania Smell Identification Test (UPSIT), and administered this to Chamorro residents with ALS (n=9), pure parkinsonism (n=9), pure dementia (n=11), PDC (n=31), and 53 neurologically normal Chamorro and 25 North American control subjects. RESULTS: Similar, marked olfactory dysfunction was found in all four syndromes of Guamanian neurodegenerative disease. This correlated poorly with measures of parkinsonism and cognition. In the neurologically normal Chamorro control group, six subjects (11%) had very low olfactory scores; these were less than the lowest North American score, raising a question of subclinical neurodegenerative disease. CONCLUSIONS: Marked olfactory deficits are common to all four Guamanian neurodegenerative syndromes, and suggest the possibility of similar central neuropathologic substrates. The deficit in the Guamanian ALS group contrasts with idiopathic ALS, in which olfactory function has been reported to be only slightly compromised.

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OBJECTIVE: To compare the frequency of use of nonsteroidal anti-inflammatory drugs (NSAIDs) among 302 incident cases of Alzheimer's disease (AD) and age- and sex-matched control subjects. DESIGN: We undertook a retrospective case-control study, using the resources of the Rochester Epidemiology Project. MATERIAL AND METHODS: In ongoing studies of dementia in Rochester, Minnesota, we identified all incident cases of AD with onset between 1980 and 1984. From among all Rochester residents who received care at Mayo Clinic Rochester during those years, we selected one age- (within 3 years) and sex-matched control subject. For this study, exposure to a prescription NSAID was defined as prescribed use for 7 or more days during the 2-year window of time encompassing the year of onset and the year before onset among cases and the corresponding index year and the year prior for control subjects. RESULTS: The odds ratio (OR) for exposure, as described, to a prescription NSAID versus no exposure to any NSAID was 0.79 (95% confidence interval [CI], 0.45 to 1.38); the OR was 1.00 (95% CI, 0.52 to 1.92) for women and 0.40 (95% CI, 0.13 to 1.29) for men. Similarly, the overall OR for aspirin exposure versus no NSAID exposure was 0.90 (95% CI, 0.54 to 1.50). CONCLUSION: These data are suggestive but not confirmatory of a protective effect of NSAIDs for AD.

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Autonomic impairment is minor in idiopathic amyotrophic lateral sclerosis (ALS) and Alzheimer's-type dementia (D) and is usually not marked in Parkinson's disease. The autonomic status of Guamanian parkinsonism (P), ALS, and parkinsonism-dementia complex (PDC) is essentially unknown. We therefore evaluated the autonomic nervous system in Guamanian D, ALS, P, and PDC. Cardiovagal, adrenergic, and postganglionic sudomotor functions were quantitated in 16 patients and 14 paired household controls. Patients comprised PDC (N = 11), D (N = 2), P (N = 2), and ALS (N = 1). Autonomic deficit was expressed on a composite autonomic scoring scale (CASS) and its subsets that corrects for the effects of age and gender. CASS severity was rated from 0 to 10 and the maximal subset scores were 3, 3, and 4 for postganglionic sudomotor, cardiovagal, and adrenergic deficits, respectively. CASS scores for mild, moderate, and severe autonomic failure are 1 to 3, 4 to 6, and 7 to 10, respectively. Symptoms were scored by an Autonomic Symptom Profile (ASP). The affected patients were older than and had a sex distribution different from paired controls (64.2 +/- 8.0 versus 53.1 +/- 13.5; p < 0.01; male/female = 9/7 versus 2/12; p = 0.045). CASS scores were markedly increased over paired controls (6.2 +/- 2.3 versus 1.9 +/- 1.3; p < 0.001), and involvement was generalized by system. There were deficits in sudomotor, cardiovagal, and adrenergic function. Orthostatic hypotension occurred in 6 of 16 patients and 2 of 14 paired controls. Guamanian patients had more autonomic dysfunction than non-Guamanian Parkinson's disease. ASP scores were higher in patients than controls and regressed with CASS. These differences persisted when corrected for the confounding effects of age, gender, and diabetes. We conclude that Guamanian patients have autonomic failure to a greater extent than non-Guamanian Parkinson's disease or ALS. This autonomic failure suggests multisystem autonomic involvement similar to but less severe than in multiple system atrophy.

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Our goal was to use cross-sectional national mortality data to provide a multivariable statistical analysis of the factors that contribute to the decision of whether an autopsy will be performed. The identification of determinants of the autopsy is an important prerequisite for finding cost-effective alternatives for arresting or reversing the decline of autopsy rates in the circumstances in which the autopsy can continue to make a crucial contribution to clinical medicine and public health. The source of the data was 1986 National Center for Health Statistics (Washington, DC) mortality data tapes for Kentucky, Maryland, Minnesota, and Washington for the 1986 calendar year. Separate multiple logistic regressions were conducted on these data on a state-by-state basis, with a total of 139,063 individual mortality records as the unit of analysis. The dependent variable in all models was autopsy (yes/no). Odds ratios for selected explanatory variables were estimated for all four states, and the relative contribution of each explanatory variable was studied in a detailed analysis of one state. In general, the following independent variables had a statistically significant positive relationship with whether an autopsy will be performed: male sex; nonwhite ethnicity; death due to ill-defined or unknown cause; death due to accident, suicide, or homicide; presence of a nationally recognized medical center in the county of death; and death occurring in a standard metropolitan statistical area. In general, the following independent variables had a statistically significant negative relationship with whether an autopsy will be performed: older age at death; higher income level of the decedent; death in a nursing home; death at home; and residency in the county of death. The two most important variables influencing the autopsy decision were age at death (especially old age) and death due to accident, homicide, or suicide.

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On the western Pacific island of Guam, parkinsonism, dementia, and amyotrophic lateral sclerosis are highly prevalent but the cause is not known. To assess the possibility that the pathologic process extends beyond the nervous system, we studied patients with Guamanian neurodegenerative disease (N = 16) and Guamanian Chamorro control subjects (N = 16) in the Clinical Research Center of the Mayo Clinic, Rochester, MN. The principal abnormalities found in those with neurodegenerative disease included diabetes mellitus in 44%, elevated levels of serum immunoglobulin A (IgA) in 50%, and elevated IgG in 44%. The mean serum IgM level in the patient group was significantly lower than in the control group. Diabetes mellitus and elevated IgA and IgG levels were also present in 31% of neurologically normal Guamanian subjects. Some of these control subjects, however, probably have preclinical neurodegenerative disease, as found in previously published postmortem studies. Extensive serologic testing did not reveal any consistent profile of autoimmunity. Other blood and urine studies failed to identify hematologic, nutritional, renal, hepatic, or metabolic abnormalities that distinguished patients. Whether diabetes mellitus or abnormalities of immune regulation share common etiopathology with Guamanian neurodegenerative disease deserves further study.

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BACKGROUND: Local complications that require additional surgical procedures are an important problem for women with breast implants. METHODS: We studied 749 women who lived in Olmsted County, Minnesota, and received a first breast implant at the Mayo Clinic between 1964 and 1991. We identified complications that occurred after the initial procedure and after any subsequent implantation. A complication was defined as a surgical procedure performed for any of the following reasons: capsular contracture; rupture of the implant; hematoma or bleeding; infection or seroma of the wound; chronic pain; extrusion, leakage, or sweating of the implant; necrosis of the nipple, areola, or flap; malfunction of the filler port of a tissue expander; and wound dehiscence. RESULTS: During follow-up (mean, 7.8 years; range, 0 to 25.8), 208 (27.8 percent) of the women underwent 450 additional implant-related surgical procedures. Ninety-one (20.2 percent) were anticipated, staged procedures or were done because the patient requested a size change or aesthetic improvement, and 359 procedures (79.8 percent) had at least one clinical indication (thus constituting a complication). Complications occurred in 178 (23.8 percent) of the 749 women and involved 274 (18.8 percent) of the 1454 breasts with implants and 321 (18.8 percent) of the 1703 implants. The most frequent problem was capsular contraction (272 cases), followed by rupture of the implant (60), hematoma (55), and wound infection (23). The rate of complications was significantly lower (P<0.001) among women with cosmetic implants (6.5 percent at one year, 12 percent at five years) than among women who underwent implantation after mastectomy for breast cancer (21.8 percent at one year, 34 percent at five years) or prophylactic mastectomy (17.3 percent at one year, 30.4 percent at five years). CONCLUSIONS: Women who have had breast implantation frequently experience local complications during the subsequent five years. Complications were significantly less frequent among patients who received implants for cosmetic reasons than among those who received implants after mastectomy for cancer or for cancer prophylaxis.

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It is evident that Guamanian amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex (PDC) are clinical variants of a single disease entity and that Guamanian ALS is clinically indistinguishable from sporadic ALS. We studied by electron microscopy the skin tissues from 11 patients with Guamanian neurodegenerative disease (PDC and ALS), 11 Chamorro control subjects, 10 Japanese patients with sporadic ALS and 11 Japanese control patients. Among patients with sporadic ALS, there was an inverse relationship of collagen fiber diameter and the duration of disease and a marked increase of amorphous material in the ground substance. These findings were not observed in the Guamanian patients or controls. Therefore, the skin studies reinforce the view of a different disease mechanism in Guamanian ALS and PDC compared to sporadic ALS.

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A historical cohort study was carried out to evaluate the effects in utero medical ionizing radiation on head circumference at birth. The nature of medical practice in Rochester, Minnesota, and the Mayo Clinic medical records linkage system enabled us to provide accurate estimates of medical radiation absorbed dose in 9,793 pregnancies of 2,980 women pregnant in Rochester between 1917 through 1973. Data were controlled for sex of the fetus, duration of pregnancy and congenital head abnormalities. It was found that medical ionizing radiation in the second and third trimesters of more than 300 mrad were related to significantly decreased head circumference. There was no significant effect of radiation exposure in the first trimester or periconceptional period. Medical ionizing radiation in the second and third trimesters of more than 300 mrad is related to a significant yet minimal, decreasing head circumference at birth. Maximum effects were seen during the midgestational and second trimester periods.

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