The effect of diabetes on abdominal aortic aneurysm growth over 2 years.

OBJECTIVE: Abdominal aortic aneurysm (AAA) is a common progressive disease and a significant cause of morbidity and mortality. Prior investigations have shown that diabetes mellitus (DM) may be relatively protective of AAA incidence and growth. The Non-invasive Treatment of Aortic Aneurysm Clinical Trial (N-TA3CT) is a contemporary study of small AAA growth that provides a unique opportunity to validate and explore the effect of DM on AAA. Confirming the effect of DM on AAA growth in this study may present opportunities to explore for clues to potential biologic mechanisms as well as inform current patient management. METHODS: This is a secondary analysis examining the association of diabetes and aneurysm growth within N-TA3CT: a placebo-controlled multicenter trial of doxycycline in 261 patients with AAA maximum transverse diameters (MTDs) between 3.5 and 5 cm. The primary outcome is the change in the MTD from baseline as determined by computed tomography (CT) scans obtained during the trial. Secondary outcome is the growth pattern of the AAA. Baseline characteristics and growth patterns were assessed with t tests (continuous) or χ2 tests (categorical). Unadjusted and adjusted longitudinal analyses were performed with a repeated measures linear mixed model to compare AAA growth rates between patients with and without diabetes. RESULTS: Of 261 patients, 250 subjects had sufficient imaging and were included in this study. There were 56 patients (22.4%) with diabetes and 194 (77.6%) without. Diabetes was associated with higher body mass index and increased rates of hypercholesterolemia and coronary artery disease (P < .05). Diabetes was also associated with increased frequency of treatment for atherosclerosis and hypertension including treatment with statin, angiotensin-converting enzyme inhibitor, angiotensin II receptor blocker, anti-platelet, and diuretic therapy (P < .05). Baseline MTD was not significantly different between those with (4.32 cm) and without DM (4.30 cm). Median growth rate for patients with diabetes was 0.12 cm/y (interquartile range, 0.07-0.22 cm/y) and 0.19 cm/y (interquartile range, 0.12-0.27 cm/y) in patients without DM, which was significantly different on unadjusted analysis (P < .0001). Diabetes remained significantly associated with AAA growth after adjustment for other relevant clinical factors (coef, -0.057; P < .0001). CONCLUSIONS: Patients with diabetes have more than a 35% reduction in the median growth rates of AAA despite more severe concomitant vascular comorbidities and similar initial sizes of aneurysms. This effect persists and remains robust after adjusted analysis; and slower growth rates may delay the time to reach repair threshold. Rapid growth (>0.5 cm/y) is infrequent in patients with DM.

Identification of Low Cardiac Output Syndrome at the Bedside: A Pediatric Cardiac Intensive Care Unit Survey.

BACKGROUND: Low cardiac output syndrome is a transient constellation of signs and symptoms that indicate the heart's inability to supply sufficient oxygen to tissues and end-organs to meet metabolic demand. Because the term lacks a standard clinical definition, the bedside diagnosis of this syndrome can be difficult. OBJECTIVE: To evaluate concordance among pediatric cardiac intensive care unit nurses in their identification of low cardiac output syndrome in pediatric patients after cardiac surgery. METHODS: An anonymous survey was distributed to 69 pediatric cardiac intensive care unit nurses. The survey described 10 randomly selected patients aged 6 months or younger who had undergone corrective or palliative cardiac surgery at a freestanding children's hospital in a tertiary academic center. For each patient, data were presented corresponding to 5 time points (0, 6, 12, 18, and 24 hours postoperatively). The respondent was asked to indicate whether the patient had low cardiac output syndrome (yes or no) at each time point on the basis of the data presented. RESULTS: The response rate was 46% (32 of 69 nurses). The overall Fleiss k value was 0.30, indicating fair agreement among raters. When the results were analyzed by years of experience, agreement remained only slight to fair. CONCLUSIONS: Regardless of years of experience, nurses have difficulty agreeing on the presence of low cardiac output syndrome. Further research is needed to determine whether the development of objective guidelines could improve recognition and facilitate communication between the pediatric cardiac intensive care unit nurse and the medical team.