The Future of Teaching Epidemiology.

The rapid pace of technological advancements and the corresponding societal innovations and adaptations make it difficult to predict how teaching epidemiology will look in the coming decades. We discuss changes in the teaching of epidemiology that are currently unfolding. First, typical epidemiology curricula often lack formal instruction in important components of causal thinking, such as the formulation of well-defined research questions. We address gaps related to causal thinking, communication about our science, and interpretation of study results, and we make suggestions of specific content to close such gaps. Second, digital technology increasingly influences epidemiology instruction. We discuss classroom and online teaching modalities in terms of challenges and advantages.

Hemodynamic effects of substance P and its receptor antagonist RP67580 in anesthetized rats with carbon tetrachloride-induced cirrhosis.

OBJECTIVE: Substance P (SP) is a vasodilator that may contribute to systemic and splanchnic vasodilatation in cirrhosis. The aim of this study was to determine the effects of SP (dose--13 pg/kg) and its specific inhibitor, RP67580 (dose--300 microg/kg) on mean arterial pressure (MAP) and portal pressure (PP) in cirrhotic rats and controls. MATERIAL AND METHODS: MAP and PP were measured before and after administering SP and RP67580. Additionally, a small group of cirrhotic rats were pretreated with L-NAME to block the effects of nitric oxide (NO) before measurements. RESULTS: SP produced transient systemic hypotension in both groups. SP caused a significant increase in PP in cirrhotic rats and a decrease in PP in controls. RP67580 reduced the hypotensive effect of SP, but not completely. RP67580 decreased PP in the cirrhotic group but not in controls. In cirrhotic rats pretreated with L-NAME, SP administration caused a significant decrease in MAP but no significant change in PP. CONCLUSIONS: Exogenous SP increases PP and decreases MAP in cirrhotic rats. RP687580 decreases PP and reduces SP-induced hypotension in cirrhotic rats. NO blockade abolishes the effect of SP on PP. SP contributes to splanchnic vasodilatation in cirrhosis and this effect may be mediated by NO.

High mortality in elderly drivers is associated with distinct injury patterns: analysis of 187,869 injured drivers.

BACKGROUND: Higher mortality in elderly drivers involved in motor vehicle collisions (MVCs) is a major concern in an aging population. We examined a spectrum of age-related differences in injury severity, outcome, and patterns of injuries using our institution's trauma registry and the National Trauma Data Bank. METHODS: Injury severity scores (ISSs) and measures of outcome were compared among five age groups (<26, 26-39, 40-54, 55-69, 70+ years) using chi tests and analysis of variance. International Classification of Diseases-9th Revision (ICD-9) codes were used to compute the frequency of specific injuries across groups. We used stratified analysis and multiple logistic regression to control for confounding. RESULTS: After the age of 25, injury severity, mortality, and length of stay (LOS) all increased progressively with age, whereas likelihood of discharge home decreased for each group (p < 0.001). Restraint use increased with age. However, age-related adverse outcomes were significantly increased even after adjusting for restraint use (p < 0.0001). Unrestrained elderly drivers had the highest mortality and morbidity (p < 0.001), and were least likely to be discharged home (p < 0.001). Abbreviated Injury Scale scores and ICD-9 codes indicated that poor outcomes with older age were driven primarily by head and chest injuries, especially intra-cranial hemorrhage, rib fractures, pneumothorax, and injury to the heart and lungs. CONCLUSIONS: Elderly drivers involved in MVCs have disproportionately poor outcomes primarily because of a greater incidence of head and chest injuries. Seat belt and airbag use in elderly drivers significantly reduce this trend but do not eliminate it. These observations should help establish clinical guidelines for the evaluation of traumatized elderly drivers, develop specific education programs, and safer vehicle design.

Influence of breast cancer margin assessment method on the rates of positive margins and residual carcinoma.

BACKGROUND: We hypothesized that the method of breast cancer margin assessment may be associated with different rates of positive margins and residual carcinoma. METHODS: A total of 178 breast cancer specimens were divided into 2 groups (A and B) based on the margin assessment method used. Rates of positive margins, re-excision, and residual carcinoma at re-excision were compared and analyzed statistically. RESULTS: At least 1 margin was positive in 64.7% in group A and in 65.2% in group B. At directed re-excision 54% in group A and 51% in group B had residual carcinoma. The lateral margin was positive in 44% in group A compared with 26% in group B (P = .06). The posterior margin was positive in 19% in group A and in 51% in group B (P = .001). CONCLUSIONS: Two different breast cancer specimen margin assessment methods had comparable rates of positive margins and residual carcinoma at re-excision. Different patterns of specific margin positivity suggest that the method of margin assessment may alter results.

Anti-Saccharomyces cerevisiae antibodies are associated with the development of postoperative fistulas following ileal pouch-anal anastomosis.

Although serologic testing for perinuclear antineutrophil cytoplasmic antibodies (pANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA) is reportedly useful in distinguishing ulcerative colitis (UC) from Crohn's disease (CD), there are few and conflicting reports assessing their utility in predicting postoperative complications after ileal pouch-anal anastomosis (IPAA). We examined the associations between postoperative complications such as pouchitis or fistulas and pANCA and ASCA antibodies in a group of patients who underwent IPAA for UC. We conducted a retrospective chart review of 34 patients initially diagnosed with UC (four of these patients had a diagnosis of indeterminate colitis) who underwent IPAA by a single surgeon, and who had pANCA and ASCA antibody levels measured during their clinical course. Study patients were assigned to four groups based on the pattern of antibody reactivity: pANCA+/ASCA- (16 patients), pANCA-/ASCA+ (nine patients), pANCA+/ASCA+ (five patients), and pANCA-/ASCA- (four patients). The median length of follow-up was 16 months (3-144 months). None of the patients (0 of 16) who were pANCA+/ASCA- had their preoperative diagnosis of UC changed after a median follow-up of 14 months (3-118 months). Of the nine patients with a preoperative diagnosis of UC who were pANCA-/ASCA+, four patients (44%) had their diagnosis changed postoperatively to CD based on clinical findings, with a median follow-up: 15 months (5-98 months). Of 16 patients who underwent IPAA and who were pANCA+/ASCA-, 15 of 16 (93.75%), were free of fistulas postoperatively, with a median follow-up of 14 months (3-118 months). Of nine patients with a preoperative diagnosis of UC who underwent IPAA and who were pANCA-/ASCA+, four of nine (44%; p = 0.04) developed fistulas postoperatively, with a median length of follow-up of 55 months (15-67 months). No relationship between serologic profiles or antibody titer levels and the development of pouchitis was identified. In a cohort of patients undergoing IPAA for UC, serologic profiles may be useful in identifying patients at risk of postoperative fistula formation. Patients who were pANCA-/ASCA+ were at increased risk for the development of fistulas postoperatively compared to patients who were pANCA+/ASCA-, and were also more likely to have their diagnosis changed postoperatively to CD. A larger study is needed to validate these observations.

Characteristics and utilization of primary care services in a torture rehabilitation center.

We conducted a retrospective chart review to look into the utilization of healthcare services of refugees. Between December 1998 and June 2001, 146 refugees received care at the Boston Center for Refugee Health and Human Rights. The mean age was 39+/- 1 years; 57% were males, and 84% were survivors of torture. A significant number of patients were diagnosed with major depression (70%), post-traumatic stress disorder (58%), past hepatitis A infection (77%), and tuberculosis classes 2 and 3 (42%). Patients had on average 2.3 +/- 0.1 initial health assessments visits and 3.6 +/- 0.3 primary care follow-up visits during a mean follow-up period of 12.8 +/- 0.8 months. Subjects with two or fewer initial health assessment visits were less likely to be undergoing psychological counseling (OR: 0.22; 95% CI:0.08-0.58), less likely to be seeking asylum (OR: 0.16; 95% CI: 0.06-0.43), and more likely to be self-referred (OR: 9.6; 95% CI:2.4-39.6). Four or fewer primary care follow-up visits were more likely in subjects who had no health insurance (OR: 7.2; 95% CI:2.0-25.5) and less likely in those referred for psychological counseling (OR: 0.017; 95% CI:0.05-0.54). Patients had a higher prevalence of mental health conditions than that reported in other studies and often declined diagnostic and therapeutic interventions.

Teaching surgical decision-making: an interactive, web-based approach.

BACKGROUND: Skillful surgical care demands proper patient assessment and decision-making. These skills are honed through long hours and years of clinical practice. A decrease in work hours is reducing the number of cases managed by medical students and residents. We have developed a set of interactive, web-based teaching modules to help fill this gap. MATERIALS AND METHODS: The modules aim to teach surgical decision-making in a convenient, nonthreatening manner. Surgical case material is presented in a graphically rich environment, including video and sound to enhance realism. At the end of each web-page, the user must make a management decision. The correct answer is subsequently provided with immediate feedback. Medical students used and evaluated the modules during their surgical clerkships. Additionally, students took a pretest and 1-week delayed posttest after completing the modules to assess the program's efficacy. RESULTS: Eight modules involving pediatric and general surgery have been completed. Medical students gave high ratings to the quality of the modules and found the interactive format both engaging and educationally effective. Eighty-seven percent of medical students rated the program's educational value as above average to excellent. On pre- and posttest analysis, students' scores improved an average of 24.8% (P < 0.001). CONCLUSION: Students enjoy web-based educational material. Additional modules covering a range of surgical topics are in development. Web-based modules appear to be an effective clinical teaching tool, well-suited for integration into the clinical curriculum.

Differences in risk factors for lower extremity arterial occlusive disease.

BACKGROUND: Patients undergoing lower extremity revascularization have associated cardiovascular risks: smoking, hypertension, dyslipidemia, and diabetes. This study evaluated the impact of cardiovascular risk factors on proximal versus distal arterial occlusive disease in patients undergoing lower extremity revascularization as adjusted to a control group without vascular disease. STUDY DESIGN: We performed a retrospective, case-control study that included 151 patients undergoing lower extremity revascularization and 229 patients undergoing knee and hip replacement (controls). Risk factors were determined for each of three separate groups undergoing revascularization for different levels of occlusive disease: aortoiliac, superficial femoral, and popliteal-tibial. Comparisons to controls were tested using t-tests or chi-square tests and multiple logistic regression. RESULTS: Dyslipidemia was associated with a significant risk of aortoiliac (odds ratio [OR]=3.4; p=0.0006) and superficial femoral occlusion (OR=2.8; p=0.01) but was less strongly associated with popliteal-tibial occlusion (OR=2.1; p=0.09). Smoking was strongly associated with aortoiliac (OR=4.5; p=0.004) and superficial femoral disease (OR=4.6; p=0.0007) but not popliteal-tibial disease (OR=1.3; p=0.53). In contrast, diabetes mellitus and chronic renal insufficiency were strong risk factors for popliteal-tibial occlusion (OR=5.4, p=0.0002; OR=3.9, p=0.01, respectively), but were not significant risk factors for aortoiliac or superficial femoral occlusion. CONCLUSIONS: These data, which use revascularization level as a surrogate marker for lower extremity arterial disease, suggest that the risk factor profile for proximal disease differs from that of distal disease. These findings may reflect differences in the biology of disease and indicate that different risk factors have various anatomic influences on arterial disease formation.

Factors associated with mortality in trauma: re-evaluation of the TRISS method using the National Trauma Data Bank.

BACKGROUND: TRISS remains a standard method for predicting survival and correcting for severity in outcome analysis. The National Trauma Data Bank (NTDB) is emerging as a major source of trauma data that will be used for both primary research and outcome benchmarking. We used NTDB data, to determine whether TRISS is still an accurate predictor of survival coefficients and to determine whether the ability of TRISS to predict survival could be improved by updating the coefficients or by building predictive models that include information on co-morbidities. METHODS: To compare the utility of different methods of TRISS calculation we identified the records of 72,517 trauma patients (62,103 blunt trauma and 10,414 penetrating trauma) who had complete information for all of the covariates to be considered in the analysis. Multiple logistic regression was used to recalculate the TRISS coefficients in models using both the original TRISS covariates and in models which also included variables for co-morbidities that could potentially affect survival. Model discrimination was evaluated by calculating the area under the receiver operating characteristic curves (AUC), and model calibration was evaluated with the Hosmer-Lemeshow Goodness-of-Fit Statistic (H-L). RESULTS: For penetrating trauma the original TRISS equation had good discriminative ability (AUC=0.98), but was poorly calibrated (H-L=267.04). When logistic regression was used to generate revised coefficients, discrimination was unchanged, but calibration improved (H-L=38.66). The only co-morbid factor significantly associated with survival after penetrating trauma was acute alcohol consumption, which was associated with increased survival (p < 0.0001). However, its inclusion in a logistic model did not improve discrimination, but improved calibration somewhat (AUC =0.98; H-L=19.95). The original TRISS equation was a less accurate predictor of survival after blunt trauma (AUC = 0.84; H-L= 10,720.7). When logistic regression was used to generate revised coefficients for the original TRISS covariates, predictions after blunt trauma improved (AUC = 0.94; H-L=25.45). With blunt trauma, acute alcohol consumption and prior hypertension were associated with increased survival, and male gender, congestive failure, cirrhosis, and prior myocardial infarction were associated with decreased survival. However, inclusion of these covariates in a logistic model did not improve predictions of survival (AUC = 0.94; H-L= 34.83). CONCLUSIONS: In the NTDB the traditional TRISS had limited ability to predict survival after trauma. Accuracy of prediction was improved by recalculating the TRISS coefficients, but further improvements were not seen with models that included information about co-morbidities.

Are varicose veins a marker for susceptibility to coronary heart disease in men? Results from the Normative Aging Study.

Clinical observations suggest that varicose veins (VV) are less frequent in patients undergoing infrainguinal bypass surgery for femoral artery occlusive disease. While some previous studies support this relationship, others report that VV are more prevalent in coronary heart disease patients (CHD). This study used the Normative Aging Study (NAS) population to examine the association between VV and symptomatic CHD. The incidence of CHD over 35 years of follow-up was determined in the 2280 initially healthy male volunteers enrolled in the NAS. The incidence of CHD in the VV population and the subjects without VV were compared using Kaplan-Meier survival curves and the log-rank test. A time-dependent proportional hazards regression method was used to further explore the relationship between VV disease and subsequent development of CHD after adjusting for other cardiovascular risk factors. A total of 569 subjects (24.9%) were diagnosed with VV prior to the development of symptomatic CHD, and 1708 (75.1%) were not. Over 35 years of follow-up, 98 subjects with VV developed symptomatic CHD (17.2%), while 363 of those without VV subsequently developed symptomatic CHD (21.2%). Kaplan-Meier survival curves suggested a reduced risk of symptomatic CHD for subjects with VV (p = 0.0001). Further exploration of this relationship in a proportional hazards multivariate model showed VV to be associated with a 36% decreased risk of symptomatic CHD after adjusting for other recognized cardiovascular risk factors. In the NAS population, men with VV were less likely to develop symptomatic CHD over the 35+ years of follow-up than were subjects without VV.

Organ-specific changes in high-energy phosphates after hemorrhagic shock and resuscitation in the rat.

BACKGROUND: Adenosine nucleotides provide energy for many essential cellular functions. Liver and intestinal ATP and energy charge are known to decrease during hemorrhagic shock, and the ability to regenerate high-energy phosphates may have important implications for recovery. We measured organ-specific changes in energy charge after hemorrhagic shock and after shock followed by resuscitation. STUDY DESIGN: Anesthetized Sprague-Dawley rats were bled and maintained at a mean arterial pressure (MAP) of 40 mmHg for 1, 2, 3, or 4 hours. Some animals were resuscitated with normal saline and shed blood (1:1) to a mean arterial pressure of 80 to 90 mmHg for 1 hour. Control animals were anesthetized, but not hemorrhaged. At the conclusion, blood gases and adenine nucleotides were measured. RESULTS: Arterial pO2 and pCO2 were normal in all groups. Unresuscitated hemorrhage caused metabolic acidosis, but bicarbonate was normal in controls and after hemorrhage followed by resuscitation. Energy charge (EC) in the gastrocnemius was unaffected by hemorrhage or resuscitation. Liver EC decreased after hemorrhage (p = 0.0001), but recovered partially after resuscitation. Kidney EC was decreased after only 3 hours of hemorrhage and 1 hour of resuscitation (p = 0.005), but not with shorter periods of hemorrhage. Lung EC decreased with shock, but was substantially worse after resuscitation (p < 0.05). CONCLUSIONS: After hemorrhage and resuscitation, EC decreased in lung, liver, kidney, and intestine, but the time course, extent of decline, and ability to recover after resuscitation varied from organ to organ. Inability to regenerate high-energy phosphates after hemorrhagic shock may be a marker for more severe cellular damage.

Incision and abdominal wall hernias in patients with aneurysm or occlusive aortic disease.

INTRODUCTION: Patients undergoing midline incision for abdominal aortic reconstruction appear to be at greater risk for postoperative incision hernia compared with patients undergoing celiotomy for general surgical procedures. Controversy exists as to whether incidence of abdominal wall hernia and increased risk for incision hernia is higher in patients with abdominal aortic aneurysm (AAA) than in patients operated on because of aortoiliac occlusive disease (AOD). We conducted a prospective multi-institutional study to assess frequency of incision hernia after aortic surgery through a midline laparotomy and of previous abdominal wall hernia. METHODS: Patients with AAA (n = 177) or AOD (n = 82) from three major institutions were prospectively enrolled in the study and examined. Data collected included demographic data, cardiopulmonary risk factors, smoking status, history of previous or current abdominal wall hernia (incision, inguinal, umbilical, femoral), previous midline incision, suture type, and postoperative complications. At a minimum of 6 months after laparotomy, patients were evaluated clinically for a new incision hernia. Differences were tested with the unpaired t test, X(2) test, or Fisher exact test, and multiple logistic regression was used to control for confounding variables. RESULTS: Mean follow-up of the cohort was 32.8 +/- 2.3 months. Rate of abdominal wall hernia and inguinal hernia in patients with AAA versus AOD was 38.4% versus 11% (P =.001) and 23.7% versus 6.1% (P =.003), respectively. Rate of postoperative incision hernia in patients with AAA was 28.2%, and in patients with AOD was 11.0% (P =.002). Adjusting for age, smoking, chronic obstructive pulmonary disease, body mass index, diabetes, bowel obstruction, and suture type, patients with AAA had almost a ninefold risk for postoperative incision hernia formation (odds ratio [OR], 8.8; P =.0049). CONCLUSION: Compared with patients with AOD, patients with AAA have a higher frequency of abdominal wall hernia and inguinal hernia, and are at significant increased risk for development of incision hernia postoperatively. The higher frequency of hernia formation in patients with AAA suggests the presence of a structural defect within the fascia. Further studies are needed to delineate the molecular changes of the aorta and its relation to the abdominal wall fascia.

Lymphedema and quality of life in survivors of early-stage breast cancer.

BACKGROUND: The standard of care for early-stage breast cancer includes surgical removal of the tumor and axillary lymph node dissection (ALND). Despite increased use of breast-conserving surgery, lymphedema rates are similar to those with more radical surgery. HYPOTHESIS: Women who experience breast cancer-related lymphedema have a measurable reduction in quality of life compared with women without lymphedema. DESIGN: In a retrospective cohort study, we explored the association between lymphedema and quality of life, controlling for patient demographics, surgical factors, and treatment types. SETTINGS: An urban academic medical center and a community hospital. PARTICIPANTS: A total of 151 women surgically treated for early-stage breast cancer (stages 0-II) were assessed at least 1 year after their ALND. The women had been treated with either conservative surgery and radiation or mastectomy without radiation. MAIN OUTCOME MEASURES: Arm volume was measured by water displacement. Grip strength and range-of-motion measurements assessed arm function. The Functional Assessment of Cancer Therapy-Breast (FACT-B) quality-of-life instrument assessed breast, emotional, functional, physical, and social well-being. RESULTS: Lymphedema (an arm volume difference > or =200 cm(3)) was measured in 42 women (27.8%). Mastectomy or conservative surgery patients had similar lymphedema rates. Women with lymphedema in both surgical groups scored significantly lower on 4 of the 5 subsections than women without lymphedema, even after adjusting for other factors influencing quality of life. CONCLUSIONS: Lymphedema occurs at appreciable rates, and its impact on long-term quality of life in survivors of early-stage breast cancer should not be underestimated.

Bovine pericardium vs dacron for patch angioplasty after carotid endarterectomy: a prospective randomized study.

HYPOTHESIS: Bovine pericardium (BP) demonstrates improved intraoperative hemostasis and equivalent perioperative morbidity compared with Dacron when used as patch material for angioplasty following carotid endarterectomy. OBJECTIVE: To prospectively compare BP and Dacron patch angioplasty after carotid endarterectomy in a randomized fashion. METHODS: Ninety-five consecutive primary carotid endarterectomies were performed in a prospective randomized fashion in 92 patients. Fifty-one procedures were performed using BP and 44 using Dacron. Intraoperative suture line bleeding was subjectively evaluated by observing bleeding at 3 and 4 minutes following carotid cross-clamp removal and then objectively weighing the sponge used to tamponade bleeding during these time intervals. Perioperative morbidity, including cervical wound hematoma, transient ischemic attack, and stroke, and perioperative mortality were recorded. Statistical analysis was performed using paired t tests, chi(2) analysis, Fisher exact test, or multiple linear regression as appropriate. RESULTS: Suture line bleeding at 3 minutes was present in 7 (14%) of 51 patients in the BP group and 24 (55%) of 44 patients in the Dacron group (P<.001). Suture line bleeding evaluated at 4 minutes was present in 2 (4%) of 51 patients in the BP group and 13 (30%) of 44 patients in the Dacron group (P =.001). Net +/- SEM sponge weight (total intraoperative suture line bleeding) was 6.25 +/- 0.55 g in the BP group and 16.34 +/- 1.85 g in the Dacron group (P<.001). Total suture line bleeding was significantly affected by activated clotting time; however, multivariate analysis demonstrated that bleeding was significantly less with BP (P<.001) even after adjusting for differences in activated clotting time. CONCLUSIONS: Bovine pericardium demonstrated a statistically significant decrease in intraoperative suture line bleeding compared with Dacron. Handling characteristics were judged by the surgeons to be superior for BP. Therefore, we believe BP may be an alternative to Dacron when performing patch angioplasty of the carotid artery after endarterectomy.

Factors that predict site of outflow target artery anastomosis in infrainguinal revascularization.

INTRODUCTION: Lower extremity revascularization is indicated for limb salvage and incapacitating leg claudication. Many risk factors (age, hypertension, diabetes, tobacco use, dyslipidemia, etc) have been associated with atherosclerosis and the development of peripheral arterial occlusive disease. However, whether these risk factors or the surgical indication (claudication or limb salvage) influences the extent and location of infrainguinal disease and hence the target artery (distal anastomosis) is unclear. This study examines the risk factors and indication for infrainguinal revascularization with respect to the type of bypass performed. METHODS: Three hundred fifty-two infrainguinal revascularizations in 282 patients were retrospectively reviewed. Patient data, including demographics, cardiovascular risk factors, indications, types of revascularization, and perioperative complications and mortality, were collected. Data were analyzed with t test, chi(2) test, Fisher exact test, and multiple logistic regression. RESULTS: The indication for surgical revascularization was claudication in 70 patients and limb salvage in 282. The likelihood of a popliteal anastomosis (above or below knee) versus a tibial or pedal anastomosis was decreased with increasing age (P =.002) and diabetes (P =.0001), and smoking increased the likelihood (P =.056). However, popliteal bypass also was strongly associated with claudication as the surgical indication (odds ratio [OR], 8.7; P =.0001), and 90% of the claudicant group had undergone popliteal anastomosis. Claudication and popliteal anastomosis were both linked to smoking; 97% of subjects who underwent operation for claudication were smokers compared with 75% of subjects who underwent tibial or pedal anastomosis for limb salvage (P =.001). After adjustment for indication, the likelihood of popliteal anastomosis was still decreased with diabetes (OR, 0.46; P =.002), and age had a borderline significant effect (P =.077). When the analysis was stratified by indication for surgery, the likelihood of popliteal bypass among patients who underwent operation for claudication was not influenced by age, diabetes, or smoking. However, within the subset of patients who underwent operation for limb salvage, the likelihood of any popliteal anastomosis was diminished by diabetes (OR, 0.50; P =.007), age (OR, 0.968 per year; P =.01), and chronic renal insufficiency (OR, 0.476; P =.04). CONCLUSION: Infrainguinal peripheral arterial occlusive disease is not a homogenous disease entity. Claudication and limb salvage are associated with two distinct patterns of vascular disease with different risk factors. Patients who undergo operation for claudication are seen at an earlier age, have a high prevalence of smoking, and have proximal disease and a greater likelihood of a popliteal anastomosis. In contrast, patients for limb salvage are less likely to have a popliteal bypass, favoring a more distal target outflow anastomosis that is strongly influenced by advanced age, diabetes, and chronic renal insufficiency.

Reimaging in pediatric neurotrauma: factors associated with progression of intracranial injury.

PURPOSE: The purpose of this study was to characterize the radiologic changes that are seen in the first 24 to 48 hours after head injury and to correlate those changes with clinical findings, to determine which children are at greatest risk for progression of their neurologic injury. METHODS: The authors identified 104 children (less-than-or-equal17 years of age) who had a second computed tomography (CT) scan of the head within 24 to 48 hours of admission. CT scans were evaluated systematically in a blinded fashion. Mechanism of injury, findings on physical examination, therapeutic measures, and changes in management were recorded from hospital medical records. The 50 children whose second CT scan showed progression of injury were compared with the 54 patients whose intracranial injuries were unchanged or improved on their second CT. RESULTS: Twenty-six percent of patients (13 of 50) with radiographic progression of injury had an admission Glasgow coma score of 15. Progression of injury was more common, however, in patients with lower Glasgow coma scores, averaging 9 on admission and 10 at the time of the second CT. Progression of injury also was more common if the initial head CT showed 3 or more intracranial injuries, mass effect, intraventricular hemorrhage, or an epidural hematoma. CONCLUSIONS: Children with an intracranial injury identified on their initial head CT scan should undergo a second scan 24 hours after injury, especially if the initial CT shows 3 or more intracranial injuries, mass effect, intraventricular hemorrhage, or an epidural hematoma. .

Pouchitis in a rat model of ileal J pouch-anal anastomosis.

Endorectal ileal pouch-anal anastomosis (IPAA) has become the operation of choice for patients with chronic ulcerative colitis. Although this procedure improves the quality of life, pouchitis remains a significant postoperative complication. Because our understanding of the pathophysiology of pouchitis may, in part, be due to the lack of small animal model, our aim was to develop a model of IPAA in a rat that mimics its clinical counterpart. Colectomy, proctectomy, construction of an ileal J pouch, and ileal pouch-rectal anastomosis as a model of IPAA was performed in Sprague-Dawley and Lewis rats. Radiographic contrast studies were performed to quantitate intestinal transit. The presence of activated neutrophils was quantified by measuring mucosal myeloperoxidase (MPO) activity. Oxidative stress was quantitated by measuring urinary 8-isoprostane (8-IP) levels. Anaerobic and aerobic bacterial counts were determined on Brucella and tryptic soy agar plates, respectively. Dextran sulfate sodium (DSS) was used to exacerbate ileal J pouch inflammation. Mortality was low, and animals gained weight normally after recovery. Stasis was documented radiographically. MPO levels were elevated (p < 0.05) in the ileal J pouch 30 and 60 days after IPAA, indicating an inflammation that was associated with stasis and bacterial overgrowth. 8-IP levels were elevated by 80% compared with controls. Oral administration of 5% DSS to IPAA rats with further elevated MPO and 8-IP levels in concert with a pouchitis-like syndrome that included the physical, gross, and histologic characteristics of clinical pouchitis. An understanding of the pathophysiology of pouchitis is essential to the future development of new therapeutic modalities. This model is applicable to investigating several key etiologic mechanisms purportedly related to pouchitis.

Fracture locations influence the likelihood of rectal and lower urinary tract injuries in patients sustaining pelvic fractures.

BACKGROUND: Rectal and lower urinary tract injuries in pelvic fractures can lead to significant complications. We sought to determine whether fracture locations could serve as markers for injury. METHODS: In our retrospective review of patients with blunt pelvic fractures, the association of fracture locations with injury to the rectum, bladder, and urethra was explored with Fisher's exact test and subsequently analyzed with multiple logistic regression. RESULTS: Of the 362 patients reviewed, 8 had rectal injury and 24 had lower urinary tract injury. The following locations were found to be significant. Rectum: symphysis pubis (relative risk [RR] = 3.3, p < 0.001) and sacroiliac (SI) joint (RR = 2.1, p = 0.014). Bladder: symphysis pubis (RR = 2.1, p < 0.001), SI joint (RR = 2.0, p < 0.001), and sacrum (RR = 1.6, p = 0.002). Urethra: symphysis pubis (RR = 2.9, p = 0.003), SI joint (RR = 1.8, p = 0.04), and inferior ramus (RR = 4.6, p = 0.008). After multivariate analysis, the primary and independent predictors for each of the injuries were as follows: rectal injury, widened symphysis; bladder injury, widened symphysis and SI joint; and urethral injury, widened symphysis and fracture of the inferior pubic ramus. Although these associations were significant, the overall prevalence of associated rectal and urologic injuries was low. Consequently, the predictive values of these radiologic findings were also low, ranging from 5% to 9% for urethral and rectal injuries to 20% for bladder injuries. CONCLUSION: Certain fracture locations are associated with increased risk for rectal, bladder, or urethral injury. Fractures involving these locations should prompt further work-up for assessment.