New frontiers in aortic therapy: focus on deep hypothermic circulatory arrest.

There is currently a paradigm shift in the conduct of adult aortic arch repair. Although deep hypothermic circulatory arrest has been the classic perfusion platform for adult aortic arch repair, recent developments have challenged this aortic arch paradigm. There has been a gradual clinical drift towards moderate, and even mild, hypothermic circulatory arrest combined with antegrade cerebral perfusion. This paradigm shift appears to be associated with equivalent clinical outcomes, and in certain settings, with improved outcomes. The advent of endovascular therapy has challenged even further the concept that circulatory arrest is required for adult aortic arch repair. These dramatic advances have resulted in the emergence of an international aortic arch surgery study group that aims to advance this dynamic field through consensus statements, meta-analysis, clinical database analysis, prospective registries, and randomized controlled trials.

Progress in platelet blockers: the target is the P2Y12 receptor.

The considerable progress in P2Y12-platelet blockers has important perioperative implications due to a family of novel agents beyond clopidogrel. Although prasugrel is more potent than clopidogrel due to more efficient hepatic metabolism, it is limited clinically by its irreversibility and bleeding risks. Ticagrelor, as the first approved direct and reversible oral P2Y12 blocker, still is limited clinically by its novel side-effect profile. Intravenous reversible P2Y12 blockade is possible now with both cangrelor and elinogrel, although both agents are still in clinical development. Furthermore, elinogrel offers the possibility of both oral and parenteral P2Y12 blockade with a single agent. Future trials likely will continue to evaluate and compare the safety and efficacy of these agents in multiple clinical settings, including the perioperative period.

The year in cardiothoracic and vascular anesthesia: selected highlights from 2012.

Cardiothoracic and vascular critical care has emerged as a subspecialty due to procedural breakthroughs, an aging population, and a multidisciplinary collaboration. This subspecialty now has a dedicated professional society, recently published guidelines, and plans for standardized certification. This paradigm shift represents a major collaboration opportunity for our specialty. The rise of evidence-based perioperative practice has produced a culture of large trials in our specialty to search for solutions to the challenging outcome questions. Besides the growth in the development of evidence, the consensus conference format and postpublication peer review have both emerged as effective processes for identifying the most relevant high-quality evidence. The quest for best perioperative practice has highlighted the importance of teamwork at all phases of care with respect to transitions in care, blood component transfusion, and research misconduct. The emergence of ultrasound as a standard for central vascular access also has been emphasized in recent multisociety guidelines. There also has been a paradigm shift in the management of patients with coronary artery disease. Recent guidelines have emphasized the roles of the cardiac anesthesiologist and the interventional cardiologist as part of the heart team approach. Major recent trials in comparative effectiveness have challenged the advantages of percutaneous coronary intervention, off-pump coronary artery bypass surgery, and intra-aortic balloon counterpulsation. The year 2012 has witnessed the emergence of new paradigms of care in our specialty with the emphasis on teamwork, safety, and quality. These processes will further improve perioperative outcome.

Fenofibrate-associated reversible acute allograft dysfunction in 3 renal transplant recipients: biopsy evidence of tubular toxicity.

Renal transplant recipients are susceptible to hyperlipidemia and the development of atherosclerosis as a consequence of the immunosuppressive agents they require, which include corticosteroids, calcineurin inhibitors, and sirolimus. Fibric acid derivatives and 3-hydroxymethylglutaryl-coenzyme A reductase inhibitors are prescribed commonly to optimize lipid profiles and reduce the risk of cardiovascular events in this type of setting. The authors describe 3 cases of reversible acute renal allograft dysfunction in patients treated with fenofibrate. Serum levels of monitored immunosuppressant agents remained therapeutic throughout the time period. Discontinuation of the fenofibrate resulted in the resolution of renal dysfunction. The pathologic changes to the proximal tubules in all 3 biopsy specimens were in keeping with a toxic rather than an ischemic etiology. Although the control of hyperlipidemia is crucial in the transplant patient population, the authors suggest that caution be exercised and serum creatinine levels be closely monitored in patients started on fibrates.

Predictors of proximal neoplasia in patients without distal adenomatous pathology.

BACKGROUND: Previous colorectal cancer screening studies have observed that some patients may have advanced proximal neoplasia without distal findings. Since these studies have included only gender, age, and family history as risk factors, they are limited in their ability to identify predictors of isolated proximal neoplasia. METHODS: Data were collected from the charts of 1,988 patients who presented for colonoscopy. Information gathered included endoscopic findings, histology, known risk factors for colorectal neoplasia, and smoking pattern. Our main outcome was the presence of proximal adenomatous neoplasia in patients who had no distal adenomas. We defined significant neoplasia as adenocarcinoma, high-grade dysplasia, villous polyps, adenomas 1 cm or greater or more than two adenomas of any size. RESULTS: Fifty-five patients had isolated significant proximal neoplasia that would have been missed on a flexible sigmoidoscopy. While patients older than 60 yr had a greater risk for this neoplasia (odds ratio = 3.01: 95% CI = 1.66-4.23; p < 0.001), those who took a daily aspirin had a reduced risk (OR = 0.60; 95% CI = 0.30-0.88; p < 0.05). A family history of colorectal cancer increased the patient's risk of having any adenomas (OR = 2.01; 95% CI = 1.33-3.40; p < 0.01) or villous tissue (OR = 2.03; 95% CI = 1.27-3.51; p < 0.05) in the proximal colon without distal findings. Smoking was associated with an increased risk of large (> 1 cm) isolated proximal tubular polyps (OR = 2.71; 95% CI = 1.64-4.46; p < 0.01) as well as isolated significant proximal neoplasia (OR = 2.30; 95% CI = 1.59-3.31; p < 0.01). CONCLUSIONS: Age greater than 60 yr, a history of at least 10 pack-years of smoking, and a family history of colorectal cancer increased the risk of finding significant proximal polyps in patients without distal pathology.

Atypical morphologic presentation of biliary atresia and value of serial liver biopsies.

BACKGROUND: Liver biopsy findings are important in diagnosing extrahepatic biliary atresia. Diffuse ductular proliferation is a characteristic finding. We describe four patients with conjugated hyperbilirubinemia in whom the initial liver biopsy findings showed a lack of ductular proliferation, despite subsequent development of biliary atresia. RESULTS: On initial biopsy, paucity of intrahepatic bile ducts was present in three of four patients, with a bile duct to portal space ratio of 0.3 to 0.4 (normal, 0.9-1.8). A normal bile duct to portal space ratio of 1.0 was observed in the fourth patient. Ductular proliferation became apparent in three subjects between 9 and 12 weeks of age, and biliary atresia was noted at the time of a Kasai portoenterostomy. The fourth child had well-developed biliary cirrhosis at liver transplantation. CONCLUSIONS: Changes characteristic of biliary atresia may appear even after 9 weeks of age. Bile duct paucity and normal bile duct to portal space ratio do not preclude the subsequent development of biliary atresia. Infants with unexplained conjugated hyperbilirubinemia and acholic stools should undergo sequential liver biopsies until clinical improvement occurs or until biliary atresia can be excluded from the differential diagnosis.