Frequency of deployed emergency donor panel use prior to implementation of the low titre group O whole blood program.

INTRODUCTION: The US military has frequently used a 'walking blood bank', formally known as an 'emergency donor panel' (EDP) to obtain warm fresh whole blood (WFWB) which is then immediately transfused into the casualty. We describe the frequency of EDP activation by the US military. METHODS: We analysed data from 2007 to 2015 within the Department of Defense Trauma Registry for US, Coalition and US contractor casualties that received at least 1 unit of blood product within the first 24 hours and described the frequency of WFWB use. RESULTS: There were 3474 casualties that met inclusion, of which, 290 casualties (8%) required activation of the EDP. The highest proportion of EDP events was in 2014, whereas the highest number of EDP events was in 2011. Median injury severity scores were higher in the recipients, compared with non-EDP recipients (29 vs 20), as were proportions with serious injuries to the abdomen (43% vs 19%) and extremities (77% vs 65%). The median number of units of all blood products, except for packed red blood cells, was higher for WFWB recipients. Of the WFWB recipients, the median was 5 units (IQR 2-10) with a maximum documented 144 units. There were four documented cases of EDP recipients receiving >100 units of WFWB with only one surviving to hospital discharge. During the study period, there were a total of 3102 (3%) units of WFWB transfused among a total of 104 288 total units. CONCLUSIONS: We found nearly 1 in 11 casualties who received blood required activation of the EDP. Blood from the EDP accounted for 3% of all units transfused. These findings will enable future mission planning and medical training, especially for units with smaller, limited blood supplies. The lessons learned here can also enable mass casualty planning in civilian settings.

Carbapenem-Resistant Enterobacterales Infection After Massive Blast Injury: Use of Cefiderocol Based Combination Therapy.

A military soldier sustained a blast injury in Afghanistan, resulting in amputations and hemipelvectomy. He developed New Delhi metallo-beta-lactamase-producing E. coli bacteremia, soft-tissue infection, and sacral osteomyelitis. These organisms are being increasingly discovered in different communities around the world. He was successfully treated with tigecycline and cefiderocol. Cefiderocol is a novel siderophore-based cephalosporine developed to treat serious infections, including those caused by carbapenem-resistant Enterobacterales.

Why despite the lower prevalence, is asthma more severe in the semiarid region?

INTRODUCTION AND OBJECTIVES: Asthma is a chronic inflammatory disease which is very prevalent throughout the world, and climatic factors, especially air humidity, have been considered fundamental to its development. This study aims to evaluate the relationship between the climate factor and the severity of asthma episodes in the semiarid region, comparing it to the coast and an intermediate climate region, considering the use of medication as an intervening factor. MATERIALS AND METHODS: Ecological study in cities with different climatic conditions (semiarid, intermediate region and Coast). Prevailing data was obtained from the International Study of Asthma and Allergies in Childhood (ISAAC) protocol. We evaluated the temperature, humidity and use of drugs for asthma/100,000 inhabitants. RESULTS: The prevalence of asthma was lower in the semiarid (14%; 95%CI=12.1-15.7) than the intermediate region (19.1%; 95%CI=17.7-20.6) and coast (17.9%; 95%CI=16.6-19.2). Episodes of severe asthma attacks were surprisingly higher in semiarid (10.4%; 95%CI=8.9-11.9) when compared to coast (4.1%; 95%CI=3.4-4.9) and intermediate region (5.0%; 95%CI=4.3-5.8). In the semiarid region, the humidity was lower and the temperature higher than the other cities evaluated. The dispensing of medications was lower in the semiarid region. CONCLUSIONS: Temperature and humidity may have contributed to a lower prevalence and greater severity of asthma in the semiarid region. The dispensing of medications was lower in the semiarid region, indicating that access to both relief and control drugs was lower in this city. The possibility of lack of health care in the semiarid region can also be another explanatory factor associated.

Inhaled beclomethasone in pregnant asthmatic women--a systematic review.

The aim of this study was to systematically review the safety and efficacy of inhaled beclomethasone for asthma treatment in pregnant women. We performed a systematic review in Medline, LILACS and SciELO electronic databases in December 2012. A total of 3433 articles were found by using the keywords asthma, pregnancy and beclomethasone. Among these, 1666 were from Medline, via PubMed, and 1767 were from LILACS and SciELO. Nine of these articles were selected. Only one paper suggested an increased foetal risk for congenital malformations, and one other for offspring endocrine and metabolic disturbances. Data are mostly reassuring, supporting the use of glucocorticoid inhalants during pregnancy, and we found no evidence of inferiority in relation to efficacy and safety of beclomethasone compared to other drugs used in pregnant asthmatic women.

Somatotype analysis of physically active individuals.

AIM: The present study aimed at comparing demographic variables, physical activity level, and health-related anthropometric indicators according to somatotype among physically active individuals. METHODS: This is a descriptive cross-sectional study, in which the sample consisted of 304 individuals, who are users of the jogging track at the Federal University of Pernambuco (UFPE) in Recife, state of Pernambuco, northeastern Brazil. Somatotypes were analyzed using the anthropometric technique proposed by Heath & Carter (1990). To assess physical activity level, we used the short version of the International Physical Activity Questionnaire (IPAQ). We used as health-related anthropometric indicators: body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), and conicity index (CI). We used descriptive statistics to characterize the sample, and then used a multivariate analysis of variance (a = 0.05) to test for differences. RESULTS: In the somatotype analysis, we observed among women significant predominance of the endomorphy and lower predominance of the ectomorphy in comparison to men. In the age group ≤ 29 years significantly lower values were found for endomorphy than in other age groups. Irregularly active individuals had significantly lower values of endomorphy. We observed that individuals with obesity and risk in WHR, WC and CI had higher scores of endomorphy and mesomorphy and lower scores of ectomorphy. CONCLUSION: The somatotype of physically active individuals in the present study raises health concern, mainly related to high relative adiposity represented by endomorphy.

Assessing caries, dental plaque and salivary flow in asthmatic adolescents using inhaled corticosteroids

Background: A number of studies have reported that inhaled corticosteroids may cause a greater incidence of caries, reduced salivary flow, changes in saliva composition and an increased frequency of dental plaque, probably through alterations in the oral microbiota. The objective was to compare the frequency of caries, dental plaque and non-stimulated salivary flow rate among asthmatic adolescents using inhaled corticosteroids and non-asthmatic adolescents, as well as the salivary biochemical parameters (pH and leucocytes) in both groups. Methods: This research has a descriptive cross-sectional design to compare dental health of 40asthmatics on inhaled corticosteroids and 40 non-asthmatic adolescents (median age 13 years).Results: The findings were a higher number of tooth surfaces affected by dental caries (median4 versus 1.5), and more dental plaques (median 70.5 versus 60.7) among asthmatic adolescents. They also had a significantly higher frequency of salivary leucocytes. The non-stimulated salivary flow was similar in both groups. Conclusions: The results suggest an association between the use of inhaled corticosteroids and an increased risk of dental caries and bacterial plaque, which calls for special attention of these patients by doctors and dental health professionals(AU)

Assessing caries, dental plaque and salivary flow in asthmatic adolescents using inhaled corticosteroids.

BACKGROUND: A number of studies have reported that inhaled corticosteroids may cause a greater incidence of caries, reduced salivary flow, changes in saliva composition and an increased frequency of dental plaque, probably through alterations in the oral microbiota. The objective was to compare the frequency of caries, dental plaque and non-stimulated salivary flow rate among asthmatic adolescents using inhaled corticosteroids and non-asthmatic adolescents, as well as the salivary biochemical parameters (pH and leucocytes) in both groups. METHODS: This research has a descriptive cross-sectional design to compare dental health of 40 asthmatics on inhaled corticosteroids and 40 non-asthmatic adolescents (median age 13 years). RESULTS: The findings were a higher number of tooth surfaces affected by dental caries (median 4 versus 1.5), and more dental plaques (median 70.5 versus 60.7) among asthmatic adolescents. They also had a significantly higher frequency of salivary leucocytes. The non-stimulated salivary flow was similar in both groups. CONCLUSIONS: The results suggest an association between the use of inhaled corticosteroids and an increased risk of dental caries and bacterial plaque, which calls for special attention of these patients by doctors and dental health professionals.

Production of interleukin-10 in asthmatic children after Beta-1-3-glucan.

BACKGROUND: Beta-1-3 Glucan is a polysaccharide extracted from Saccharomyces cerevisiae with a possible immunomodulating action that may have a favourable action on asthma symptoms and other allergic diseases. An experimental study carried out using a murine respiratory model detected a decrease in pulmonary tissue eosinophilia, as well as an increase in Interleukin-10 (IL-10) after glucan use. METHODS: This open, exploratory study with blind outcome evaluation included asthmatic children between 6 and 12 years of age with mild to moderate persistent asthma and inadequate disease control (rescue medication needed more than twice a week) in spite of inhaled budesonide 400 microg/day. After a four week run-in period, subcutaneous Beta-1-3-glucan injections were given weekly for the first four weeks and then every two weeks for the last four weeks. IL-10 levels, measured by the immunoenzymatic method (ELISA), were compared before and after glucan administration. RESULTS: Twenty patients (14 male and 6 female) were included. Mean IL-10 levels were 6.4 pg/ml and 11.3 pg/ml before and after glucan, respectively (p = 0.02). There was also a reduction of asthmatic symptoms score at the end of study. CONCLUSIONS: This is the first study which shows that subcutaneous particulate Beta-1-3-glucan increases serum IL-10 levels in asthmatics. The possibility of glucan being able to modulate allergic sensitisation and having a beneficial action in restoring Th2 function should be assessed by means of properly planned controlled clinical trials, as it may represent a new therapeutic strategy.

Sensitisation to aeroallergens among asthmatic and non-asthmatic adolescents living in a poor region in the Northeast of Brazil.

OBJECTIVES: To assess the kind and frequency of sensitisation to aeroallergens (skin prick test - SPT) of asthmatic and non-asthmatic adolescents (13-14 years old) living in the city of Caruaru, Northeast of Brazil, and to analyse their exposure to some environmental factors. METHOD: A case-control study was conducted with asthmatic (50) and non-asthmatic (150) adolescents diagnosed by the International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire. All were submitted to SPT with aeroallergens (house dust mites, cat and dog epithelium, cockroaches, moulds and grass) and completed a questionnaire to evaluate their environmental exposure. RESULTS: There were no significant differences between groups regarding gender, age, number of siblings and environmental exposure. Asthmatic subjects exhibited a higher frequency of positive SPTs than non-asthmatic subjects (54.0% vs 33.3%, p=0.009) mainly due to Periplaneta americana (34.0% vs 12.7%, p=0.0007 respectively) and Canis familiaris (20.0% vs 8.7%, p=0.029). CONCLUSION: Although sensitisation to aeroallergens was high among non-asthmatic adolescents, asthma was associated with parental history of atopic disease and sensitisation to P. americana and Canis familiaris but not to D. pteronyssinus showing that local studies are mandatory for the tailoring of appropriate management of allergic diseases.

Geohelminth infections: a review of the role of IgE and assessment of potential risks of anti-IgE treatment.

Geohelminth infections are major parasitic infections with a worldwide distribution. Immunoglobulin E (IgE) is considered to play a central role in protective immunity against these parasites although the evidence from experimental animal models infected with helminth parasites and treated with anti-IgE antibodies and from observational studies in human populations of the immunologic correlates of protective immunity against helminths do not support a critical role for IgE in mediating protection against helminths. Anti-IgE treatment of human allergic disorders using a humanized monoclonal IgE antibody (omalizumab, Xolair) has been approved for clinical use in the USA and Europe and there is concern that this treatment may be associated with increased morbidity in populations exposed to helminth infections. A recently published randomized controlled trial investigating the risk of geohelminth infections in allergic patients receiving omalizumab in Brazil has provided some evidence that omalizumab may not be associated with increased morbidity attributable to these parasites. This review examines the evidence for a role of IgE in protective immunity against helminth parasites, discusses the findings of the randomized controlled trial, assesses the potential risks and provides recommendations for anti-IgE treatment in groups of allergic patients with different exposure risks for helminth infections.

Children and adolescents infected with Wuchereria bancrofti in Greater Recife, Brazil: a randomized, year-long clinical trial of single treatments with diethylcarbamazine or diethylcarbamazine-albendazole.

In filariasis-endemic areas beyond sub-Saharan Africa, the World Health Organization's recommended strategy for interrupting transmission of the causative parasites is annual, single-dose, mass treatment with a combination of diethylcarbamazine (DEC; given at 6 mg/kg) and albendazole (ALB; given at 400 mg) for 4-6 years (the minimum estimated life-span of the adult parasites). In an open, hospital-based, randomized and controlled trial, with a blinded evaluation of outcome, 82 children and adolescents from Recife, all with Wuchereria bancrofti microfilaraemias, were given either DEC alone (6 mg/kg) or the same dose of DEC combined with ALB (at 400 mg/patient). Every 90 days for 1 year after the single treatment, each patient was checked for microfilaraemia by the filtration of up to 5 ml of venous blood collected at night. One year post-treatment, 16 (39%) of the 41 patients given DEC alone and 20 (49%) of the 41 given DEC-ALB were found microfilaraemic (relative risk=0.8, with a 95% confidence interval of 0.49-1.31) and the corresponding geometric mean levels of microfilaraemia were 2.0% and 1.8% of the levels recorded immediately pre-treatment, respectively (P>0.05). In terms of the prevalences and intensities of microfilaraemia, therefore, the addition of ALB to the DEC appeared to offer no significant benefit.

There are more asthmatics in homes with high cockroach infestation.

Although asthma has been commonly associated with sensitivity to cockroaches, a clear causal relationship between asthma, allergy to cockroaches and exposure levels has not been extensively investigated. The objective of the present study was to determine whether asthma occurs more frequently in children living in homes with high cockroach infestation. The intensity of household infestation was assessed by the number of dead insects after professional pesticide application. Children living in these houses in the metropolitan area of Recife, PE, were diagnosed as having asthma by means of a questionnaire based on the ISAAC study. All children had physician-diagnosed asthma and at least one acute exacerbation in the past year. Children of both sexes aged 4 to 12 years who had been living in the households for more than 2 years participated in this transverse study and had a good socioeconomic status. In the 172 houses studied, 79 children were considered to have been exposed to cockroaches and 93 not to have been exposed. Children living in residences with more than 5 dead cockroaches after pesticide application were considered to be at high infestation exposure. Asthma was diagnosed by the questionnaire in 31.6% (25/79) of the exposed group and in 11.8% (11/93) of the non-exposed group (P = 0.001), with a prevalence ratio of 3.45 (95%CI, 1.48-8.20). The present results indicate that exposure to cockroaches was significantly associated with asthma among the children studied and can be considered a risk factor for the disease. Blattella germanica and Periplaneta americana were the species found in 96% of the infested houses.

There are more asthmatics in homes with high cockroach infestation

Although asthma has been commonly associated with sensitivity to cockroaches, a clear causal relationship between asthma, allergy to cockroaches and exposure levels has not been extensively investigated. The objective of the present study was to determine whether asthma occurs more frequently in children living in homes with high cockroach infestation. The intensity of household infestation was assessed by the number of dead insects after professional pesticide application. Children living in these houses in the metropolitan area of Recife, PE, were diagnosed as having asthma by means of a questionnaire based on the ISAAC study. All children had physician-diagnosed asthma and at least one acute exacerbation in the past year. Children of both sexes aged 4 to 12 years who had been living in the households for more than 2 years participated in this transverse study and had a good socioeconomic status. In the 172 houses studied, 79 children were considered to have been exposed to cockroaches and 93 not to have been exposed. Children living in residences with more than 5 dead cockroaches after pesticide application were considered to be at high infestation exposure. Asthma was diagnosed by the questionnaire in 31.6 percent (25/79) of the exposed group and in 11.8 percent (11/93) of the non-exposed group (P = 0.001), with a prevalence ratio of 3.45 (95 percentCI, 1.48-8.20). The present results indicate that exposure to cockroaches was significantly associated with asthma among the children studied and can be considered a risk factor for the disease. Blattella germanica and Periplaneta americana were the species found in 96 percent of the infested houses.

Stroke in surgery of the thoracic aorta: incidence, impact, etiology, and prevention.

OBJECTIVES: To determine the incidence, impact, etiology, and methods for prevention of stroke after surgery of the thoracic aorta. METHODS: A total of 317 thoracic aortic operations on 303 patients (194 male, 109 female) aged 13 to 87 years (mean 61 years) were reviewed. There were 218 procedures on the ascending aorta and arch and 99 on the descending aorta. Of the 218 procedures on the ascending aorta and arch, 86 involved cardiopulmonary bypass, 122 involved deep hypothermic circulatory arrest, 2 involved antegrade cerebral perfusion, and 8 involved "clamp and sew" or left heart bypass. Of the 99 procedures on the descending aorta, 20 involved "clamp and sew," 69 involved left heart or full bypass, and 10 involved deep hypothermic circulatory arrest. A total of 206 cases were elective and 97 were emergency operations. RESULTS: Twenty-three (7.3%) of 317 patients had a stroke. Fifteen strokes occurred in operations on the ascending aorta and 8 in operations on the descending aorta (6.9% vs 8.1%; P =.703). Stroke occurred in 16 (16.5%) of 97 emergency operations and 7 (3.4%) of 206 elective operations (P =.001). In the 300 patients surviving the operation, stroke was a significant predictor of postoperative death (9/23 [39.1%] vs 23/277 [8.3%]; P =.001). Analysis of operative reports, brain images, and neurologic consultations revealed 15 of the 23 strokes were embolic, 3 were ischemic, 3 hemorrhagic, and 2 indeterminate. Patients with stroke had longer intensive care unit stays (18.4 vs 6.8 days; P =.0001), longer times to extubation (12.7 vs 3.8 days; P <.0012), longer postoperative stays (31.4 vs 14.3 days; P =.001), and decreased age-adjusted survival (relative risk 2.775; P =.0013). After implementation of a rigorous antiembolic regimen, both strokes and mortality trended downward. CONCLUSIONS: (1) Stroke complicates surgery of both the ascending and descending thoracic aorta and warrants consideration in decision making. (2) Strokes are largely embolic. (3) Antiembolic measures for particles and air are essential, including gentle aortic manipulation, thorough debridement, transesophageal echocardiography to identify aortic atheromas, carbon dioxide flooding of the field, and (in descending cases) proximal clamp application before initiating femoral perfusion.

Multicomponent targeted intervention to prevent delirium in hospitalized older patients: what is the economic value?

INTRODUCTION: Delirium, or acute confusional state, is a common and serious occurrence among hospitalized older persons. Current estimates suggest that delirium complicates hospital stays for more than 2.3 million older persons each year, involving more than 17.5 million hospital days and accounting for more than $4 billion (1994 dollars) of Medicare expenditures. A 40% reduction was recently reported in the risk for delirium among hospitalized older persons receiving a multicomponent targeted risk factor intervention (MTI) strategy to prevent delirium, compared with subjects receiving usual hospital care.1 Before recommending that this preventive strategy be implemented in clinical practice, however, the cost implications must be thoroughly examined as well. METHODS: The present analysis performs net cost evaluations of the MTI for the prevention of delirium among hospitalized patients. Hospital charge and cost-to-charge ratio data are linked to a database of 852 subjects, who were treated with MTI or usual care. Multivariable regression methods were used to help isolate the impact of MTI on hospital costs. These results were then combined with our earlier work on the impact of the MTI on delirium prevention to assess the cost effectiveness of this intervention. RESULTS: The MTI significantly reduced nonintervention costs among subjects at intermediate risk for developing delirium, but not among subjects at high risk. When MTI intervention costs were included, MTI had no significant effect on overall health care costs in the intermediate risk cohort, but raised overall costs in the high risk group. CONCLUSIONS: Because the MTI prevented delirium in the intermediate risk group without raising costs, the conclusion reached is that it is a cost effective treatment option for patients at intermediate risk for developing delirium. In contrast, the results suggest that the MTI is not cost effective for subjects at high risk.

Physician gender and cesarean sections.

BACKGROUND: Among consumers insurers, and providers there is pervasive concern regarding the high incidence of cesarean section delivery. To date, attempts to reduce these rates have focused on the clinical behavior of providers resulting in only minimal changes. Therefore, non-medical variables must be investigated as potential explanatory factors for the decision to perform cesarean delivery. METHODS: Data were collected on clinical and non-clinical factors for obstetrician-gynecologists delivering at Yale-New Haven Medical Center to measure the impact of these factors on the performance of cesarean sections. Specifically, variation in patient demographic, ante- and intra-partum risk variables, practice setting, and doctor-specific characteristics were examined. Using contingency table and logistic regression analyses the contribution of selected factors was evaluated. RESULTS: Multivariate modeling revealed that male physicians were significantly more likely than their female colleagues to perform cesarean section. This relationship was particularly strong in the university practice setting. CONCLUSIONS: Efforts to reduce the incidence of cesarean section need to focus on the continuing education of health care providers and the delineation of non-clinical factors as essential elements in the election of specific clinical therapies.

Natural history, pathogenesis, and etiology of thoracic aortic aneurysms and dissections.

The natural history of thoracic aortic aneurysms and dissections is diverse, reflecting a broad spectrum of etiologies which include increasing aortic size, hypertension, and genetic factors. The pathogenesis is related to defects or degeneration in structural integrity of the adventitia, not the media, which is required for aneurysm formation. The ascending and descending aorta appear to have separate underlying disease processor that lead to a weakened vessel wall and an increased susceptibility for dissection. Etiologic factors for aortic aneurysms and dissections are multifactorial, reflecting genetic, environmental, and physiologic influences.

Pathologic variants of thoracic aortic dissections. Penetrating atherosclerotic ulcers and intramural hematomas.

This article confirms the existence of two variants of acute aortic pathology, the penetrating atherosclerotic ulcer (PAU) and the intramural hematoma (IMH), which are radiologically distinct from classic aortic dissection. Table 4 reviews the characteristics distinguishing PAU from classic aortic dissection and IMH. We took as a matter of definition that classic aortic dissection involves a flap which traverses the aortic lumen. We defined PAU and IMH as nonflap lesions, with PAU demonstrating a crater extending from the aortic lumen into the space surrounding the aortic lumen. This categorization can be summarized with the expression, "no flap, no dissection." With these definitions made, re-review of the imaging studies for the present report identified 36 such lesions out of 214 cases originally read as aortic dissection. Therefore, these variant lesions accounted for over 1 out of 8 acute aortic pathologies. Besides confirming the existence of the conditions, PAU and IMH, as distinct radiographic lesions, this series strongly suggests that these two conditions constitute distinct clinical entities as well. Table 4 summarizes the clinical patterns of these two entities as apparent from the present study, and contrasts them with classic aortic dissections. In particular, the following observations, some of which are consonant findings in smaller series, can be made regarding the typical patient profiles of PAU and IMH from the present study: The patients with PAU and IMH are distinctly older than those with type A aortic dissection (74.0 and 73.9 versus 56.5 years, P = 0.0001). Although not statistically significant, PAU and IMH patients tend to be older than patients with type B aortic dissections as well. For PAU and IMH, unlike aortic dissection, the concentration in the elderly is manifested in a very small standard deviation of the mean age (see Fig. 13); these two entities, PAU and IMH, are essentially diseases of the seventh, eighth, and ninth decades of life. Patients with PAU and IMH are almost invariably hypertensive (about 94% of cases). The pain of PAU and IMH mimics that of classic aortic dissection, with anterior symptoms in the ascending aortic lesions and intrascapular or back pain with descending aortic lesions. Unlike classic dissection, PAU and IMH do not produce branch vessel compromise or occlusion and do not result in ischemic manifestations in the extremities or visceral organs. PAU and IMH are more focal lesions than classic aortic dissection, which frequently propagates for much or the entire extent of the thoracoabdominal aorta. PAU is uniformly associated with severe aortic arteriosclerosis and calcification, whereas classic dissection often occurs in aortas with minimal arteriosclerosis and calcification. PAU and IMH tend to occur in even larger aortas than classic aortic dissection (6.2 and 5.5 versus 5.2 cm, P = 0.01). PAU and IMH are strongly associated with AAA, which is seen concomitantly in 42.1% of PAU patients and 29.4% of IMH patients. PAU and IMH are largely diseases of the descending aorta (90% for PAU and 71% for IMH). Although our pathology data is limited, we do feel that an inherent difference in the histologic intramural level of the hematoma may underlie the pathophysiologic process that determines which patient develops a typical dissection and which develops an intramural hematoma. In particular, we feel that the level of blood collection is more superficial, closer to the adventitia, in IMH than in typical aortic dissection. This may explain why the inner layer does not prolapse into the aorta on imaging studies or when the aorta is opened in the operating room. This more superficial location would also explain the high rupture rates as compared to classic aortic dissection (Fig. 14, Table 3). We did find PAU and IMH to behave much more malignantly than typical descending aortic dissection. As seen in Figure 6, the rupture rate is much higher than for aortic dissection. Docume

Interpreting data on thoracic aortic aneurysms. Statistical issues.

Reliable information on growth rates and risk factors for growth of thoracic aortic aneurysms (TAA) is important for managing patients with this potentially lethal condition. This article reviews existing procedures for ascertaining TAA growth rates and describes improved statistical methodologies. Using data from the Yale Center for Thoracic Aortic Disease, the article demonstrates that the statistical procedure of instrumental variables (IV) estimation leads to substantially more precise and robust estimates of TAA growth rates and associated risk factors. We recommend that IV estimation be routinely employed in estimating the progression of thoracic aortic aneurysms and in identifying risk factors for growth. The article also discusses the issue of sample selection effects that arise when patients receive graft surgery and therefore are removed from the data set, and describes statistical procedures fro addressing this issue.

Developing surgical intervention criteria for thoracic aortic aneurysms.

In summary, the development of intervention criteria is a complex and challenging endeavor. Specific examination of this issue is crucial to the appropriate clinical care of patients. With these objectives in mind, we have drawn upon our clinical experience to design, by way of statistical analysis, reasoned size criteria for intervention. These intervention criteria must be carefully weighed against the patient's age, overall physical condition, and anticipated life expectancy. We have approached the development of criteria for intervention using statistical methodology from the standpoint of preventing complications (i.e., dissection and rupture). Symptomatic states, organ compression, concomitant aortic insufficiency, and acute ascending aortic dissection are well-accepted general indications for surgical intervention regardless of aortic size. The appendix incorporates the size criteria developed in the present study as an integral component within a comprehensive strategy for managing patients with TAA. This study confirms that aneurysms of the thoracic aorta are potentially lethal, that attentive follow-up is critical, and that adverse events can be anticipated based on size criteria. As we continue to expand our database, we hope to refine further statistically-based recommendations for surgical intervention. Multi-institutional patient enrollment, with the concomitant statistical power of larger patient numbers, would considerably strengthen this type of analysis.