Timely bolus insulin for glucose control during cardiopulmonary bypass

Hyperglycemia during cardiopulmonary bypass (CPB) with glucose containing cardioplegia is common; normoglycemia is difficult to maintain and failure to do so may result in worse outcomes. The purpose of this quality improvement initiative was to show that a simple timely insulin bolus is more effective for glucose control during CPB with glucose containing cardioplegia than conventional (not standardized) glucose management in historical case-matched controls. A single bolus of insulin (.2 international units per kilogram; iu/kg) was administered, at the time of aortic cannulation, to 211 consecutive patients undergoing cardiac surgery with CPB and glucose containing cardioplegia. A further .1 iu/kg bolus of insulin was given for blood glucose (BG) measurements greater than 10.0 mmol/L (180 mg/dL) during CPB. The control group of 211 historical case-matched patients had glucose management according to anesthesiologist preference (insulin as a bolus, bolus plus infusion, infusion only, or no insulin). The frequency of hyperglycemia (BG > 11.0 mmol/L; 198 mg/dL) during CPB was significantly less in the study group (22; 10.5%) than in the control group (117; 55.5%) (p < .0001). Hyperglycemia in the first 6 hours in the intensive care unit was also significantly less frequent in the study group (5; 2.4%) than in the control group (14; 6.6%) (p = .03). Severe hypoglycemia (BG < 2.8 mmol/L; 50.4 mg/dL) occurred in one patient (.47%) in the timely bolus insulin group and five patients (2.3%) in the control group (p = .09). The timely bolus insulin method is more efficacious, but equally safe, in preventing hyperglycemia during CPB with glucose containing cardioplegia, compared with conventional (not standardized) insulin treatment in historical case-matched controls.     

Solid-pseudopapillary tumor of the pancreas: two cases in male patients

Solid-pseudopapillary tumor (SPT) of the pancreas is a rare lesion with low malignant potential occurring predominantly in young women. This is a report of two cases in young male patients. Clinical data were retrieved retrospectively from a prospective database of patients with pancreatic tumors. The two patients were caucasian males, ages 34 years (Pt1) and 41 years (Pt2) at the time of diagnosis. Pt1 presented with intermittent epigastric pain, nausea, and vomiting. Computed tomography (CT) scan showed a 9-cm mass involving the pancreatic head. He underwent pancreaticoduodenectomy, with en bloc segmental colectomy due to mesocolon involvement. Pt2 was asymptomatic, diagnosed with abdominal mass by screening ultrasound. He had an 11-cm tumor involving the pancreatic tail encasing the splenic vessels on CT. He underwent distal pancreatectomy with splenectomy en bloc. Pathology in both cases was reviewed by staff pathologists as well as outside consultants. SPT is a rare tumor of the pancreas that is diagnosed primarily in young women. The cases presented here demonstrate SPT of the pancreas in two men. In both cases, the clinical presentation was relatively unremarkable. Both have had benign late postoperative courses, consistent with the low malignant potential of this lesion.     

Ex vivo extended left hepatectomy with caval preservation, temporary portacaval shunt, and reconstruction of the right hepatic vein outflow using a reversed portal vein bifurcation graft

Liver resections that require ex vivo techniques occur rarely, but when done are generally performed on veno-veno bypass to maintain venous return and decompress the portal circulation during the anhepatic phase of the procedure. We describe an ex vivo extended left hepatectomy that was performed with preservation of the inferior vena cava and the use of a temporary portacaval shunt to eliminate the need for veno-venous bypass. Ex vivo resection allowed reconstruction of right hepatic vein branches, using the patient's reversed portal vein bifurcation as a graft to provide venous outflow.     

Functional-anatomical validation and individual variation of diffusion tractography-based segmentation of the human thalamus

Parcellation of the human thalamus based on cortical connectivity information inferred from non-invasive diffusion-weighted images identifies sub-regions that we have proposed correspond to nuclei. Here we test the functional and anatomical validity of this proposal by comparing data from diffusion tractography, cytoarchitecture and functional imaging. We acquired diffusion imaging data in eleven healthy subjects and performed probabilistic tractography from voxels within the thalamus. Cortical connectivity information was used to divide the thalamus into sub-regions with highest probability of connectivity to distinct cortical areas. The relative volumes of these connectivity-defined sub-regions correlate well with volumetric predictions based on a histological atlas. Previously reported centres of functional activation within the thalamus during motor or executive tasks co-localize within atlas regions showing high probabilities of connection to motor or prefrontal cortices, respectively. This work provides a powerful validation of quantitative grey matter segmentation using diffusion tractography in humans. Co-registering thalamic sub-regions from 11 healthy individuals characterizes inter-individual variation in segmentation and results in a population-based atlas of the human thalamus that can be used to assign likely anatomical labels to thalamic locations in standard brain space. This provides a tool for specific localization of functional activations or lesions to putative thalamic nuclei.     

Comparative effectiveness of beta-adrenergic antagonists (atenolol, metoprolol tartrate, carvedilol) on the risk of rehospitalization in adults with heart failure

Placebo-controlled randomized trials have demonstrated the efficacy of selected beta blockers on outcomes in chronic heart failure (HF), but the relative effectiveness of different beta blockers in usual clinical care is poorly understood. We compared 12-month risk of rehospitalization for HF associated with receipt of different beta blockers in 7,883 adults hospitalized for HF within 2 large health plans between January 1, 2001 and December 31, 2002. Beta-blocker use was ascertained from electronic pharmacy databases and readmissions within 12 months were identified from hospital discharge databases. Extended Cox regression was used to examine the association between receipt of different beta blockers and risk of readmission for HF after adjustment for potential confounders. During follow-up, there were 3,234 person-years of exposure to beta blockers (39.3% atenolol, 42.0% metoprolol tartrate, 12.3% carvedilol, and 6.4% other). Crude 12-month rates of readmissions for HF were high overall (42.6 per 100 person-years). After adjustment for potential confounders, cumulative exposure to each beta blocker, and propensity to receive carvedilol compared with atenolol, adjusted risks of readmission were not significantly different for metoprolol tartrate (adjusted hazard ratio 0.95, 95% confidence interval 0.85 to 1.05) or for carvedilol (adjusted hazard ratio 0.92, 95% confidence interval 0.74 to 1.14). In conclusion, in a contemporary cohort of high-risk patients hospitalized with HF, we found that adjusted risks of rehospitalization for HF within 12 months were not significantly different in patients receiving atenolol, shorter-acting metoprolol tartrate, or carvedilol.     

Clinical Use and Molecular Mechanisms of Action of Extract of Ginkgo biloba Leaves in Cardiovascular Diseases

Ginkgo biloba is one of the oldest living tree species that has been referred to as a living fossil. Extract from Ginkgo biloba leaves (GBE) is among the most commonly used herbal drugs and is popularized for its alleged tonic effect and possible curative and restorative properties. There is an increasing evidence of the potential role of GBE in treating cardiovascular diseases. We examined the history of GBE usage and reviewed the literature on its effects on the cardiovascular system. In the extensive studies involving cell cultures and animal models, GBE has been shown to exert its action through diverse mechanisms. GBE has been reported to have antioxidatant properties, to modify vasomotor function, to reduce adhesion of blood cells to endothelium, to inhibit activation of platelets and smooth muscle cells, to affect ion channels, and to alter signal transduction. In addition, relevant clinical trials with CBE are being carried out, particularly in the treatment of arterial and venous insufficiency and in the prevention of thrombosis. Finally, the controversial clinical findings and the possible adverse interactions between GBE and other drugs are discussed. This review underscores the potential benefits of Ginkgo biloba in cardiovascular diseases, highlights the gaps in our current research, and suggests the necessity for more rigorous systematic investigation of cardiovascular properties of CBE.