Norman J. Snow

Tranexamic acid reduces postbypass blood use: A double-blinded, prospective, randomized study of 210 patients

BACKGROUND Pharmacologic intervention to minimize postbypass bleeding and blood product transfusions has received increasing attention for both medical and economic reasons. METHODS Two hundred ten patients were entered into a double-blinded, prospective, randomized study to receive either 10 g of fibrinolytic inhibitor tranexamic acid before incision (n = 104) or 250 mL of placebo saline solution (n = 106). All subjects requiring cardiopulmonary bypass were deemed suitable, including those having first-time coronary bypass grafting, valve replacement, and reoperation. RESULTS There were no statistically significant differences between the groups with respect to demographic or operative characteristics. The tranexamic acid group had a 48% reduction in 24-hour blood drainage (p < 0.001) and received 69% fewer total units of packed red blood cells, 83% fewer total units of plasma, and 75% fewer platelet transfusion units than controls. Only 13 of 104 tranexamic acid patients received blood products versus 33 of 106 controls (p < 0.001). The incidences of thrombotic complications, perioperative myocardial infarction, renal failure, and neurologic complications were not significantly different between the two groups. The tranexamic acid group had 0% mortality versus 1.9% for controls (not significant). CONCLUSIONS Tranexamic acid is safe and effective in reducing blood loss and blood use in a wide variety of cardiac surgical patients.

Primary neuroendocrine tumors of the thymus

Primary neuroendocrine tumors of the thymus are highly aggressive tumors that rarely occur. A little more than 200 cases have been reported, many of which were single case reports. Only a few articles contained modest series from single centers for analysis. A review of 157 cases collected from the major series reported to-date show a clinical pattern with male preponderance (male:female ratio, 3:1) and a mean age of 54 years. Most patients presented with symptoms and signs of local compression. Almost 50% of these tumors were functionally active and were associated with endocrinopathies. Several histologic variants have been described, all with similar ultrastructural features. The biologic behavior of these tumors shows a direct relation to the degree of differentiation. Whenever possible, surgical resection is the treatment of choice as adjuvant therapy is controversial and has been used with variable success. Potential therapies exploit the presence of somatostatin receptors on a variety of these tumors. Use of radiolabeled Octreotide for radionuclide therapy has yielded tumor inhibition in animal models and may have clinical application. Fifty-one percent of the patients survived 3 years, 27% survived 5 years, and less than 10% survived beyond 10 years. Histologic grade, tumor extension, and early detection are the most important factors affecting survival. Other prognostic factors that impact outcome include presence of endocrinopathy, incomplete resectability, nodal status, and presence of distant metastasis.

Outcomes of lung transplantation in patients with scleroderma

Patients with pulmonary insufficiency due to scleroderma have long been considered suboptimal candidates for lung transplantation. This has been supported by small single-center experiences that did not reflect the entire U.S. experience. We sought to evaluate the outcome of patients with scleroderma who underwent lung transplantation. We conducted a retrospective review of 47 patients with scleroderma who underwent lung transplantation at 23 U.S. centers between 1987 and 2004 and were reported to the United Network for Organ Sharing. Women constituted 57% of the patients. The mean age was 46 years. Twenty-seven patients received single lung transplants (57%), and the remaining received double lung transplants. The mean cold ischemia time was 4.1 hours. There were 7 early deaths (≤30 days) and 17 late deaths (> 30 days). The causes of early death were primary graft failure and a cardiac event in two patients each and bacterial infection and stroke in one patient each. Late mortality was due to infection in seven patients, respiratory failure in three, malignancy in two, and multisystem organ failure, rejection, pulmonary hypertension, and a cardiac event in one patient each. The causes of early and late death were not recorded for two patients. One patient received a second transplant owing to graft failure of the first. Twenty-three patients (49%) were alive at a mean follow-up of 24 months. The Kaplan-Meier 1- and 3-year survival rates were 67.6% and 45.9% respectively, which are not significantly different from those of 10,070 patients given transplants for other lung conditions during the same period (75.5% and 58.8% respectively, P = 0.25). Donor gender, recipient’s age, and type of transplant did not affect survival. In carefully selected patients with scleroderma who have end-stage lung disease, lung transplantation is a valid life-saving therapeutic option. Available data suggest acceptable short-term morbidity and mortality and a long-term survival similar to that of patients given transplants for other lung conditions.

Appropriate Use of Emergency Department Thoracotomy: Implications for the Thoracic Surgeon

BACKGROUND Practice guidelines for the appropriate use of emergency department thoracotomy (EDT) according to current national resuscitative guidelines have been developed by the American College of Surgeons Committee on Trauma (ACS-COT) and published. At an urban level I trauma center we analyzed how closely these guidelines were followed and their ability to predict mortality. METHODS Between January 2003 and July 2010, 120 patients with penetrating thoracic trauma underwent EDT at Mount Sinai Hospital (MSH). Patients were separated based on adherence (group 1, n=70) and nonadherence (group 2, n=50) to current resuscitative guidelines, and group survival rates were determined. These 2 groups were analyzed based on outcome to determine the effect of a strict policy of adherence on survival. RESULTS Of EDTs performed during the study period, 41.7% (50/120) were considered outside current guidelines. Patients in group 2 were less likely to have traditional predictors of survival. There were 6 survivors in group 1 (8.7%), all of whom were neurologically intact; there were no neurologically intact survivors in group 2 (p=0.04). The presence of a thoracic surgeon in the operating room (OR) was associated with increased survival (p=0.039). CONCLUSIONS A policy of strict adherence to EDT guidelines based on current national guidelines would have accounted for all potential survivors while avoiding the harmful exposure of health care personnel to blood-borne pathogens and the futile use of resources for trauma victims unable to benefit from them. Cardiothoracic surgeons should be familiar with current EDT guidelines because they are often asked to contribute their operative skills for those patients who survive to reach the OR.

Utility of Silicone Esophageal Bypass Stents in the Management of Delayed Complex Esophageal Disruptions

BACKGROUND The objective of this study was to review the clinical experience of temporarily placing an endoesophageal silicone salivary bypass stent and its value in managing patients with life-threatening esophageal disruptions. METHODS Clinical records of patients undergoing placement of silicone Montgomery salivary bypass stents from June 1998 to September 2007 were reviewed. Seventeen patients had a proven esophageal disruption in the absence of malignancy and with life-threatening sepsis refractory to conventional management. Underlying conditions were iatrogenic trauma from prior pulmonary surgery (4 patients), significant anastomotic leaks after an esophagogastrectomy (4 patients), delayed presentation (> 24 hours) of a perforated esophagus (4 patients), leak after esophageal surgery (3 patients), and esophagobronchial fistula secondary to inflammation and infection (2 patients). Stents were placed without securing, were sutured in place to the esophageal wall at the time of thoracotomy, or were secured by bringing holding sutures through the nostrils and tied over the bridge of the nose. RESULTS In all cases, placement of the esophageal stent led to prompt improvement of the leak and, within a week, improvement of the sepsis. Supportive measures were continued after placement of the stent. Sixteen patients overcame the sepsis with ultimate healing of the esophageal disruption (13 patients) or maturation of the perforation into a chronic fistula (3 patients). Endoscopic stent removal was performed 2 to 16 weeks after placement. No patient had a stricture develop at the disruption site. One patient died of ruptured thoracic aorta. CONCLUSIONS Silicone salivary bypass stents serve as an effective way of diverting and excluding the oral-alimentary stream, thereby providing optimal conditions for sepsis control. They are a useful adjunct in the management of complex esophageal conditions.

Replacement of degenerated mitral and aortic bioprostheses without explantation

BACKGROUND The most common indication for reoperation in patients with a bioprosthetic valve is primary tissue failure. Explantation of the bioprosthesis is time consuming, and for a mitral valve, may be complicated by cardiac rupture at the atrioventricular junction or the posterior left ventricular wall where a strut is imbedded, injury to the circumflex artery, and late perivalvular leak; for an aortic valve, annular disruption and perivalvular leak may complicate explantation. A new approach to simplify these procedures and avoid these complications, by excising only the bioprosthetic tissue and attaching a bileaflet mechanical valve to the intact stent, was developed in 1991 and was evaluated over a 9-year period in 50 patients who had had one (34), two (10), three (4), or four (2) previous open cardiac operations. METHODS Since 1991, we have replaced degenerated mitral bioprostheses in 34 patients (25 to 84 years of age; 12 male, 22 female) by preserving the stent and suturing a St. Jude or Carbomedics bileaflet valve to the atrial side of the bioprosthetic cuff; the mitral valve was exposed through a median sternotomy in 21 patients and through a right anterolateral thoracotomy in 13. Using a similar approach, starting in 1995, 16 additional patients (55 to 73 years of age; 11 male, 5 female) with degenerated aortic bioprostheses had the aortic valve replaced by excising the bioprosthetic tissue and amputating the struts, then suturing a Carbomedics valve to the aortic side of the bioprosthetic cuff. This allows the use of a bileaflet valve similar in size to the bioprosthesis with exact matching of the orifices. RESULTS Bypass time averaged 61 +/- 14 minutes and aortic cross-clamp time 43 +/- 12 minutes. There has been no operative mortality. Three late deaths occurred at 9, 37, and 58 months, and were not valve related. No gradients of hemodynamic significance have been detected on transesophageal echocardiographic follow-up. CONCLUSIONS Leaving the bioprosthetic cuff intact eliminates the need for extensive dissection, thus shortening and simplifying the procedure and diminishing its attendant mortality and morbidity. This valve-on-valve approach also allows replacement of a degenerated bioprosthesis with a bileaflet valve of comparable size rather than a smaller one jammed into the orifice of the bioprosthetic stent, thus avoiding undue trauma to the bileaflet valve and maintaining excellent hemodynamic function.

Recent Developments in Antithrombotic Therapy: Will Sodium Warfarin Be a Drug of the Past?

Warfarin and heparin have formed the mainstay in the prophylaxis of deep vein thrombosis (DVT), stroke prevention in atrial fibrillation, and treatment of thromboembolic disease (TED). However, these choices are hampered by difficult administration, interactions with other medications, side effect profile, and limited indications for treatment. Anti-factor Xa (anti-Xa) inhibitors have already entered the drug market with the drug Fondaparinux being the first anti-Xa inhibitor to be approved for use in the U.S. by the Food and Drug Administration (FDA), and other drugs such as idraparinux being currently in development. A new class of medications, known as direct thrombin inhibitors (DTI), includes the parental agents lepirudin, argatroban and bivalirudin which have been approved by the FDA and the oral agents ximelagatran, melagatran and dabigatran. The latter three drugs which are oral DTIs may soon replace warfarin and heparin as the preferred medications for DVT prophylaxis and for reducing the relative risk of stroke. These drugs do not rely on blocking serine proteases nor do they require a co-factor (antithrombin III) like unfractionated heparin (UFH) or low molecular weight heparin (LMWH). DTIs are rapid in onset, easy to administer, do not interact with other medications or foods, have limited side effects, and can be administered in a fixed dose. The DTI ximelagatran has already been approved in several European and Asian countries, and over a dozen randomized clinical trials have been conducted demonstrating its performance to be on par with warfarin. However, approval by the FDA in the U.S. remains pending in view of reported incidences of elevations in hepatic enzymes that are currently under evaluation. This review examines the role of DTIs in the prevention and treatment of TED and the recent patents reported in the literature.

Weathering the storm: How can thoracic surgery training programs meet the new challenges in the era of less-invasive technologies?

OBJECTIVE The introduction of new technologies has shifted some resident index procedures to nonsurgical specialists. We examined the operative case volume of thoracic surgery residents during the last 6 years to objectively identify changes and trends. METHODS Program and resident data from 2002 to 2007 were entered into a database and analyzed. Program match information was obtained from the National Resident Matching Program. Resident operative experience and board examination results were obtained from the American Board of Thoracic Surgery. RESULTS A total of 795 residents qualified for the written American Board of Thoracic Surgery examination; 627 residents graduated from 2-year programs, and 168 residents graduated from 3-year programs. The total number of resident cases was higher in 3-year programs compared with 2-year programs in all 10 index categories studied (P < .01). The total volume of cases has not significantly increased in 2-year programs. The volume of coronary artery bypass graft surgeries decreased in every resident program model studied. The volume of general thoracic cases increased in all program models. Two-year, 2-resident programs had the lowest volume in 5 of the 10 categories, reaching significance in 3 categories. The written board pass rate was lower among 2-year programs than among 3-year programs (86% vs 95%, respectively, P = .003). CONCLUSION Training programs have so far weathered the storm by maintaining index volume with a new case mix, but significant trends in revascularization procedures are concerning. This study indicates a significant advantage in case volume and board pass rates among 3-year programs. Thoracic residency programs should be reorganized so that the number of residents does not exceed the capacity of the program to provide a meaningful experience.

Pulmonary venous drainage into the left atrial appendage facilitates transplantation of the left lung with difficult exposure.

Heterotopic implantation of the pulmonary venous confluence into the left atrial appendage during left lung transplantation is a reasonable alternative technique to reestablish venous drainage when exposure of the native left pulmonary veno-atrial connection may be problematic. We used this approach in a 39-year-old woman with chronic bronchiectasis who underwent bilateral sequential lung transplantation through a clam-shell approach. Dense hilar scarring and a small left atrial size made exposure of the native left pulmonary veno-atrial connection difficult.

Peripheral ischemia due to retroperitoneal fibrosis

Two patients with retroperitoneal fibrosis demonstrated symptoms of peripheral vascular ischemia. Arteriolysis to free the distal aorta and iliac vessels was successful in both patients. Aortography in the posteroanterior view was equivocal, but the accompanying urologic abnormalities and a history of methysergide ingestion helped establish the etiology of the ischemia. The most direct approach to the treatment of the vascular obstruction caused by retroperitoneal fibrosis is complete arteriolysis. Most previous reports indicate that it is relatively easy to establish a dissection plane between the fibrotic plaque and the vessel wall. We found that the fibrotic process invaded the vessel wall. Accordingly, the surgeon must anticipate a difficult, tedious dissection when performing arteriolysis for the treatment of vascular compression secondary to retroperitoneal fibrosis.