Scielo RSS <![CDATA[Revista médica de Chile]]> vol. 139 num. 9 lang. pt <![CDATA[SciELO Logo]]> <![CDATA[<b>175 years of the National Library of Medicine, of the Unites States of America</b>: <b> a scientific and cultural treasure worthy of admiration</b>]]> The National Library of Medicine (NLM) of the United States of America, celebrates in 2011 its 175th anniversary. This Library, the largest biomedical library in the world, has a proud and rich history serving the health community and the public, especially since its transfer to the National Institutes of Health in Bethesda, Maryland, in 1968. It holds 17 million publications in 150 languages, and has an important collection of ancient and modern historical books as well as original publications of Vesalius and other founders of biomedicine. Its modern document collections illustrate the progress of medical sciences. These collections include laboratory notes from many scientists whose work forms the foundations of contemporary life sciences. The Library also provides several services for health research and for the public, including databases and services such as MedLine and BLAST. The NLM constantly strives to fulfill the information needs of its customers, whether scientists or the public at large. For example, as the Hispanic population of the Unites States has increased in recent years, the NLM has made larger and larger amounts of data available in Spanish to fulfill the health information needs of this population. NLM programs train professionals in library science and biomedical informatics and link biomedical libraries of 18 academic centers throughout the United States. The NLM funds competitive grants for training at the Library, organizing short instruction courses about library science and informatics, and writing books on health related matters including the history of medicine and public health. The NLM is managed and maintained by an outstanding and farsighted group of professionals and dedicated support staff. Their focus on serving and reaching both the biomedical community and the public at large has been crucial to its development into a world icon of biomedical sciences, information technology and the humanities. <![CDATA[<b>Thrombolysis for acute ischemic stroke with recombinant tissue plasminogen activator in a Chilean public hospital</b>]]> Background: The only accepted treatment for acute ischemic stroke is thrombolysis with recombinant tissue plasminogen activator (t-PA). It was implemented in Chile in 1996, although its use was mainly restricted in Chile to private clinics. Recently, at year 2009, we have implemented this treatment in a public hospital. Aim: To describe the results of treatment of acute ischemic stroke with t-PA in a public hospital in Chile. Material and Methods: Prospective analysis of all eligible patients with acute ischemic stroke that were admitted within 4 hours of its onset and had no contraindications for thrombolysis. Results: In an eight months period, a total of 19 intravenous thrombolyses were performed in 12 males and seven females aged 28 to 79 years old. The mean lapse between onset of symptoms and onset of thrombolysis was 190 ± 57 min. Results were favorable, according to Rankin and National Institute of Health Stroke scales. Ninety days after treatment, 63% of patients had minimal or absent disability, 26% had moderate disability and only one (5%) had severe disability. One patient had a clinically not significant intracranial hemorrhage and one patient died six days after thrombolysis. Conclusions: These results indicate that thrombolysis can be successfully implemented in Chilean public hospitals. The limitations for its use in this setting are mostly administrative. <![CDATA[<b>Itraconazole 800 mg for the prophylaxis of fungal infections in patients with acute leukemia and severe neutropenia</b>]]> Background: Systemic fungal infections and specifically invasive aspergillosis (IA) are associated with a high morbi-mortality rate in patients with hematologic malignancies. Itraconazole kinetic studies show that plasma levels are not satisfactory, even though there is a reduction of the severity in clinical cases. Aim: To evaluate the results of oral prophylaxis with high dose itraconazole, 400 mg bid, among patients with adult acute leukemia. Material and Methods: Prospective analysis of 93 high risk febrile episodes (with an absolute neutrophil count of less than 500 x mm3 for more 10 days), that occurred in 76 patients. Results: Seventy five percent of episodes occurred in patients with acute myeloid leukemia and 25% in patients with acute lymphoblastic leukemia. Fifty two percent occurred during the induction of chemotherapy. Median duration of severe neutropenia was 21 days (range 10-48). Median duration of itraconazole prophylaxis was 17 days (range 6-34). A low frequency of invasive fungal infections was observed (17%). According to diagnostic criteria, 5% of episodes corresponded to persistent fever , 1% and 11% of episodes, to probable or possible IA, respectively. No confirmed or proven IA was observed. Mortality of IA was 18%. No serious adverse events due to itraconazole were observed. Conclusions: The use of high dose itraconazole prophylaxis in adult patients with acute leukemia and severe neutropenia was associated to low incidence and mortality of invasive mycoses. <![CDATA[<b>Results of treatment of acute lymphoblastic leukemia in two cohorts of Mexican patients</b>]]> Background: GIMEMA ALL 0288 trial was designed to evaluate the impact of a 7-day prednisone (PDN) pretreatment on complete remission of acute lymphoblastic leukemia. We adopted this trial in 2007. Aim: To evaluate the results of treatment in two cohorts of patients with acute lymphoblastic leukemia, treated from 2007 to January 2009 and from February to December 2009. Material and Methods: We studied 99 patients treated in the first period (58 males) and 54 patients treated in the second period (33 males) The age of patients ranged from 16 to 60 years and 70% of patients were of high risk. BCR/ABL fusion transcript was present in 12% of patients. Results: Remission rates were 61 and 51% for patients of the first and second group of treatment, respectively. The main cause of death were infections during the induction period. There were 49 relapses, mainly detected in the blood marrow. Global and event free 34 months survival were 32 and 30% respectively. Multivariate analysis disclosed risk stratification and central nervous system infiltration as risk factors for mortality. Conclusions: The main obstacles for the treatment of acute lymphoblastic leukemia in these cohorts of patients were the high incidence of infections and the lack of use of growth stimulating factors. <![CDATA[<b>Resistance phenotypes and genotypes of Streptococcus pyogenes clinical isolates in Chile over a 10-year period</b>]]> Background: Macrolide and lincosamide resistance in Streptococcus pyogenes is due to the acquisition of mef, ermB and ermA genes, which confer different resistance phenotypes, namely M, MLSBconstitutive and MLSBinducible respectively. The last report of resistance in Chile was done in the period 1990-1998, in which resistance to macrolides was 5.4%, with M phenotype as the predominant one. Aim: To characterize the evolution of erythromycin and clindamycin resistance and their associated genes in S. pyogenes strains isolated from patients with invasive and non-invasive infections in the period 1996 to 2005. Material and Methods: Resistance to erythromycin and clindamycin was determined in 1,282 clinical isolates using the disk diffusion test. Resistant isolates were analyzed by polymerase chain reaction (PCR) for the presence of the above mentioned resistance genes. Results: Global resistance to erythromycin and clindamycin was 3.5 and 0.7% respectively. Eighty percent of the resistant strains possessed the M. phenotype. Conclusions: Resistance levels of S. pyogenes have decreased in Chile in the last years. Most resistant strains have M phenotype in contrast to many countries in which the MLSB constitutive phenotype is the predominant one. <![CDATA[<b>Logistic and production process in a regional blood center</b>: <b>modeling and analysis</b>]]> Background: The blood supply chain is a complex system that considers different interconnected elements that have to be synchronized correctly to satisfy in quality and quantity the final patient requirements. Aim: To determine the blood center maximum production capacity, as well as the determination of the necessary changes for a future production capacity expansion. Material and Methods: This work was developed in the Blood Center of Concepción, Chile, operations management tools were applied to model it and to propose improvement alternatives for the production process. The use of simulation is highlighted, which permitted the replication of the center behavior and the evaluation of expansion alternatives. Results: It is possible to absorb a 100% increment in blood demand, without making major changes or investments in the production process. Also it was possible to determine the subsequent steps in terms of investments in equipment and human resources for a future expansion of the center coverage. Conclusions: The techniques used to model the production process of the blood center of Concepción, Chile, allowed us to analyze how it operates, to detect "bottle necks", and to support the decision making process for a future expansion of its capacity. <![CDATA[<b>Transesophageal echocardiography to monitor fluid administration during the perioperative period</b>]]> Background: During the perioperative period an adequate intravascular volume must be maintained. Current recommendations overestimate perioperative volume requirements. Aim: To compare perioperative volume administration using standard monitoring methods or guided by left ventricular filling parameters. Material and Methods: Twenty-four patients subjected to colon resection were randomized to monitoring by electrocardiography, blood and central venous pressure, or by transesophageal echocardiography. In the latter, volume administration was adjusted to maintain basal values of left ventricular end diastolic volume and cardiac index. Results: Patients with the standard monitoring system and transesophageal echocardiographic monitoring received 21.1±12 and 6.3 ± 2 ml/kg/h of fluids during the perioperative period, respectively (p < 0.01). Conclusions: The use of transesophageal echocardiography significantly reduced the perioperative fluid administration. <![CDATA[<b>Assessment of the impact of event scale revised for post traumatic stress disorder in Chilean subjects</b>]]> Background: Impact of Event Scale Revised (IES-R), that evaluates the subjective perception of stress, is used to assess post traumatic stress disorder simptoms. Aim: To adapt and validate IES-R to the Chilean population. Material and Methods: Two hundred seventy eight subjects exposed to stressful life events of varying magnitude were assessed using the IES-R, the Beck Depression Inventory, the anxiety and somatoform subscales of the Depressive, Anxiety and Somatoform Disorders Scale and the AUDIT Questionnaire. Results: IES-R had adequate psychometric properties in terms of internal consistency, test-retest reliability, convergent and discriminating validity. It identified a principal factor, explaining 67% of the variance. Conclusions: The IES-R can be used in the Chilean population to assess the degree of suffering produced by a traumatic event. <![CDATA[<b>Development of a virtual model of fibro-bronchoscopy</b>]]> A virtual model of fibro-bronchoscopy is reported. The virtual model represents in 3D the trachea and the bronchi creating a virtual world of the bronchial tree. The bronchoscope is modeled to look over the bronchial tree imitating the displacement and rotation of the real bronchoscope. The parameters of the virtual model were gradually adjusted according to expert opinion and allowed the training of specialists with a virtual bronchoscope of great realism. The virtual bronchial tree provides clues of reality regarding the movement of the bronchoscope, creating the illusion that the virtual instrument is behaving as the real one with all the benefits in costs that this means. <![CDATA[<b>Prevalence of chronic kidney disease in subjects consulting in urban primary care clinics</b>]]> Background: Chronic kidney disease (CKD) is a major worldwide public health problem and is associated with increased risk of cardiovascular disease and death. Aim: To assess CKD prevalence in urban Primary Care Services (PCS) of Concepcion, Chile. Material and Methods: The clinical records of 27.894 adults aged 55 ± 18 years (66% females), consulting in outpatient clinics and in whom serum creatinine was measured, with or without assessment of urine albumin levels, were reviewed. The glomerular filtration rate (eGFR) was estimated using the Modification of Diet in Renal Disease (MDRD)-4 equation. CKD was defined as an eGFR < 60 ml/min/1.73 m2 and classified according to the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NFK-KDOQI) guidelines. Results: Mean eGFR was 77.1 ± 16.3 ml/min/1.73 m2. Twelve percent of subjects had CKD (women, 14.5% and men 7,4%, p < 0,05). The prevalence of stages 3, 4 and 5 of CKD were 11.6, 0.3 and 0.2 % respectively. eGFR was negatively correlated with age ( r = -0,54, p < 0,05). Among patients with an eGFR < 60 ml/min/1.73 m2, 96.3% had eGFR 30-59, 2.3% 15-29 and 1.4 % < of 15. Seventy nine percent were women. 75.1% were aged 65 years or more, 26.8% had a serum creatinine equal or less than 1.0 mg/dL and 40.5% had microalbuminuria. Only 1% of outpatients ascribed to Cardiovascular or Diabetes Programs had the diagnosis of CKD registered. Independent risk predictors of CKD were age &gt; 60 years, female sex and microalbuminuria. Conclusions: This study showed a high prevalence of CKD in ambulatory patients, mainly among women and older people. The low level of diagnosis of CKD in cardiovascular and diabetes programs is of concern. <![CDATA[<b>Psychophysiological distress among health care professionals working in Chilean public hospitals</b>]]> Background: The public health reform in Chile resulted in changes in working conditions and organization of health centers. Aim: To examine the presence of psychophysiological symptoms in professionals of public hospitals in the Metropolitan Region and their association with current working conditions. Material and Methods: A questionnaire of quality of working life was applied to a sample of 80 physicians and 110 nurses. The questionnaire considers scales and open questions. Results: Nurses had a higher level of discomfort than physicians (p < 0.01) and had significantly higher scores for emotional distress, physical fatigue, digestive disorders, headache, insomnia, back pain and muscle tension (p < 0.01). There were statistically significant negative correlations between psychophysiological distress and working conditions (r = -0.418), social climate (r = -0.395), satisfaction with the organization (r = -0.337) and psychosocial well-being (r = -0.267). A regression model showed that 21% of the variance in psychophysiological distress was explained by working conditions, psychosocial well-being and adaptation to the organization. Conclusions: There is a relationship between the high prevalence of psychophysiological symptoms and bad working conditions of public health professionals. <![CDATA[<b>Sub capsular splenic hematoma in a sickle cell trait carrier. Case report</b>]]> Drepanocytic anemia is an uncommon hereditary disease in Chile. The heterozygous state of drepanocytic anemia or "sickle trait" has a frequency of 8% among Afro-Americans. A small number of patients carrying hemoglobin S are homozygous, with clinical manifestations of hemolytic anemia and thrombotic disease. Sickle trait is usually asymptomatic. We report a 59-year-old male who presented an acute abdominal pain and dyspnea while staying at high altitude. Six days later, an angio CAT scan showed the presence of a subcapsular splenic hematoma that was managed conservatively. Sickle cell induction with sodium metabisulphite was positive. Hemoglobin electrophoresis confirmed the sickle trait. <![CDATA[<b>Addisonian crisis caused by metastatic lung cancer</b>: <b>Report of one case</b>]]> Addisonian crisis as a first manifestation of metastatic disease secondary to cancer is uncommon. We report a 63-year-old man with a history of one year of fatigue, weakness, weight loss and repeated symptomatic hypoglycemia. The cortisol stimulation test with ACTH confirmed primary adrenal insufficiency. While receiving adequate treatment with oral hydrocortisone, he presented an adrenal crisis that was treated properly. A CT scan of the lung demonstrated a nodule in the upper right lobe and bilateral adrenal tumors. The biopsy of the lesion revealed a lung adenocarcinoma. The staging with positron emission tomography using 18 fluoroglucose (PET/CT18F- FDG) showed hypermetabolic uptake in the primary lung tumor and in both adrenal glands, suggesting metastatic implants. <![CDATA[<b>Venous thrombosis secondary to catheter insertion for hypothermia after cardiac arrest</b>: <b>Report of one case</b>]]> To improve survival and reduce neurological injury, the use of mild hypothermia following cardiac arrest has been recommended. We report a 65 years old woman who presented an out-of-hospital ventricular fibrillation and cardiac arrest. The patient was comatose following initial resuscitation and was admitted into the ICU, where cooling was initiated using an intravascular catheter. After 48 hours, rewarming was initiated. Although no neurological impairment was observed, physical examination of the right inguinal area and echo-Doppler examination revealed an extensive catheter-related thrombophlebitis with right ileocaval vein occlusion., with high risk of masive and life threatening pulmonary embolism. We report a clinical case and review the literature to point out the need for a high index of diagnostic suspicion of deep venous thrombosis in these specific setting. <![CDATA[<b>Tungiasis</b>: <b>Report of one case</b>]]> We report a 54-year-old male that, after working in a rural zone of Rio de Janeiro, Brazil, presented with an itching cutaneous lesion in the wrist with a black small central zone. The patient extracted from the lesion a on of 0.5 mm diameter. The pathological study of the insect recognized its body segments. The epidemiological background and the characteristics of the lesion led to the diagnosis of tungiasis. <![CDATA[<b>Strategies for the prophylaxis of thromboembolic disease among medical patients</b>]]> Thromboembolic disease is the main preventable cause of in-hospital death. Approximately 10% of nosocomial deaths are attributable to pulmonary embolism and in most cases, the diagnosis is not suspected before the autopsy. There are cost effective measures to decrease the incidence of thromboembolic disease. Pharmacological prophylaxis decreases the incidence of deep venous thrombosis by 65% and the incidence of pulmonary embolism by 35 to 55%. Despite this data and the presence of clinical guidelines, prophylaxis of thromboembolic disease is used only in 40% of medical patients and in 65% of surgical patients with recommended indications. We review the evidence that supports the use of thromboprophylaxis and the different strategies that may increase the compliance of physicians with its use. A protocol implemented in our institution is also proposed. <![CDATA[<b>Bronchiolar disorders: clinical-radiological assessment and classification</b>]]> Bronchiolar disorders are generally difficult to diagnose. A detailed clinical history may point toward a specific diagnosis. Pertinent clinical questions include history of smoking, collagen vascular disease, inhalation injury, medication use and organ transplantation. It is important also to evaluate possible systemic and pulmonary signs of infection, evidence of air trapping, and high-pitched expiratory wheezing, which may suggest small airways involvement. Pulmonary function tests and plain chest radiography may demonstrate abnormalities; however, they rarely prove sufficiently specific to obviate bronchoscopic or surgical biopsy. High-resolution CT (HRCT) scanning of the chest is often an important diagnostic tool to guide diagnosis in these difficult cases, because different subtypes of bronchiolar disorders may present with characteristic image findings. Some histopathologic patterns of bronchiolar disease may be relatively unique to a specific clinical context but others are nonspecific with respect to either etiology or pathogenesis. Primary bronchiolar disorders include acute bronchiolitis, respiratory bronchiolitis, follicular bronchiolitis, mineral dust airway disease, constrictive bronchiolitis, diffuse panbronchiolitis, and other rare variants. Prominent bronchiolar involvement may be seen in several interstitial lung diseases, including hypersensitivity pneumonitis, collagen vascular disease, respiratory bronchiolitis-associated interstitial lung disease, cryptogenic organizing pneumonia, and pulmonary Langerhans’ cell histiocytosis. Large airway diseases that commonly involve bronchioles include bronchiectasis, asthma, and chronic obstructive pulmonary disease. The clinical and prognostic significance of a bronchiolar lesion is best determined by identifying the etiology, underlying histopathologic pattern and assessing the correlative clinic-physiologic-radiologic context. <![CDATA[<b>Should we hydrate terminally ill patients?</b>]]> Terminally ill patients frequently have difficulties with fluid and food intake. The indication of artificial hydration in these patients has been subject of intense debate in the past years and the clinical practice widely varies, mostly based on anecdotal data and not on clinical evidence about risks and benefits associated to artificial hydration in terminal patients. There are not only technical questions concerning benefits and risks associated to artificial hydration, but also questions related to the ethical principles and values involved. Several topics, such as the effect of artificial hydration alleviating symptoms or reversing neurological alterations as delirium, its life prolonging effect or if it promotes unnecessary suffering, are discussed. In this review we will analyze clinical benefits and risks associated to artificial hydration in terminal patients, making reference to some ethical principles involved. <![CDATA[<b>Scientific ethics of the abortion with anencephalic fetus</b>]]> author proposes, from the perspective of the Scientific Ethics, to assimilate anencephalic fetuses to non-human fetuses because they have a large deficiency of the brain that is the organ for human specificity. This proposal comes after considering arguments and facts from ontogeny, phylogeny, from the situation of loss of the brain in the adult life and from the organic specificity of the human condition given by the brain. If anencephalic fetuses are not human, the interruption of their pregnancy cannot be considered as abortion, regardless the pregnancy stage. <![CDATA[<b>Clinical decissions in primary health care</b>]]> author proposes, from the perspective of the Scientific Ethics, to assimilate anencephalic fetuses to non-human fetuses because they have a large deficiency of the brain that is the organ for human specificity. This proposal comes after considering arguments and facts from ontogeny, phylogeny, from the situation of loss of the brain in the adult life and from the organic specificity of the human condition given by the brain. If anencephalic fetuses are not human, the interruption of their pregnancy cannot be considered as abortion, regardless the pregnancy stage. <![CDATA[<b>Trans rectal biopsies and radical prostatectomy</b>]]> author proposes, from the perspective of the Scientific Ethics, to assimilate anencephalic fetuses to non-human fetuses because they have a large deficiency of the brain that is the organ for human specificity. This proposal comes after considering arguments and facts from ontogeny, phylogeny, from the situation of loss of the brain in the adult life and from the organic specificity of the human condition given by the brain. If anencephalic fetuses are not human, the interruption of their pregnancy cannot be considered as abortion, regardless the pregnancy stage.