Lori D. Conklin

Thoracoabdominal aortic aneurysm repair: review and update of current strategies

BACKGROUND Surgical repair of thoracoabdominal aortic aneurysms remains a technically challenging operation that requires a multimodality approach to preventing ischemic complications. The purpose of this report is to update our experience and highlight our current clinical strategies. METHODS Between January 1, 1986 and December 31, 2001, 1,773 patients underwent thoracoabdominal aortic aneurysm repair. The majority of these patients (1,153, 65%) required Crawford extent I or II repairs. Segmental intercostal or lumbar arteries were reattached in 1,082 patients (61%); left heart bypass was used in 686 patients (38.7%), and 173 patients (9.8%) had cerebrospinal fluid drainage. RESULTS The 30-day survival rate was 94.3% (1,672 patients). Postoperative complications included renal failure requiring hemodialysis in 105 patients (5.9%) and paraplegia or paraparesis in 79 patients (4.5%). Actuarial 5-year survival was 73.5% +/- 1.6%. CONCLUSIONS This clinical experience demonstrates that current technical strategies enable patients to undergo thoracoabdominal aortic aneurysm repair with excellent early survival and acceptable morbidity.

Morbidity and mortality after extent II thoracoabdominal aortic aneurysm repair

BACKGROUND Surgical repair of Crawford extent II thoracoabdominal aortic aneurysms (TAAAs) carries substantial risk for morbidity and mortality. The purpose of this study was to analyze the results of a large consecutive series of extent II TAAA repairs and identify factors that influence morbidity and survival. METHODS Of 1,415 consecutive patients who underwent TAAA operations over a 13-year period, 442 (31.2%) had extent II repairs. Data from a prospectively maintained database were analyzed to determine which factors were associated with death and major complications. RESULTS The operative mortality was 10.0% (44 patients). Postoperative complications included paraplegia/paraparesis in 33 patients (7.5%), pulmonary complications in 158 (35.7%), and renal failure in 69 (15.9%). Multivariable analysis revealed that renal insufficiency (odds ratio [OR] 2.6), increasing age (OR 1.1/year), and increasing red blood cell transfusion requirements (OR 1.1/U) were predictors for mortality; renal insufficiency (OR 2.8) and peptic ulcer disease (OR 9.3) were predictors of renal failure; and rupture (OR 6.3) was a predictor of paraplegia. Left heart bypass was an independent protective factor against paraplegia (OR 0.4). CONCLUSIONS This contemporary experience demonstrates acceptable levels of morbidity and mortality in this high-risk group. Left heart bypass was found to provide protection against paraplegia in these patients.

Renal perfusion during thoracoabdominal aortic operations: cold crystalloid is superior to normothermic blood

BACKGROUND Renal failure remains a common complication of thoracoabdominal aortic aneurysm repair. The purpose of this randomized clinical trial was to compare two methods of selective renal perfusion--cold crystalloid perfusion versus normothermic blood perfusion--and determine which technique provides the best kidney protection during thoracoabdominal aortic aneurysm repair. METHODS Thirty randomized patients undergoing Crawford extent II thoracoabdominal aortic aneurysm repair with left heart bypass had renal artery perfusion with either 4 degrees C Ringers lactate solution (14 patients) or normothermic blood from the bypass circuit (16 patients). Acute renal dysfunction was defined as an elevation in serum creatinine level exceeding 50% of baseline within 10 postoperative days. RESULTS One death occurred in each group. One patient in the blood perfusion group experienced renal failure requiring hemodialysis. Ten patients (63%) in the blood perfusion group and 3 patients (21%) in the cold crystalloid perfusion group experienced acute renal dysfunction (p = 0.03). Multivariable analysis confirmed that the use of cold crystalloid perfusion was independently protective against acute renal dysfunction (p = 0.02; odds ratio, 0.133). CONCLUSIONS When using left heart bypass during repair of extensive thoracoabdominal aortic aneurysms, selective cold crystalloid perfusion offers superior renal protection when compared with conventional normothermic blood perfusion.

Randomized comparison of cold blood and cold crystalloid renal perfusion for renal protection during thoracoabdominal aortic aneurysm repair

OBJECTIVE More effective adjuncts are needed to reduce the incidence of acute renal injury after thoracoabdominal aortic aneurysm (TAAA) repair. The purpose of this randomized trial was to determine whether renal perfusion with cold blood provides better protection against renal ischemia than perfusion with cold crystalloid in patients undergoing TAAA repair with left heart bypass. METHODS One hundred seventy-two patients were enrolled. Strict inclusion criteria were used, including planned Crawford extent II or III TAAA repair with left heart bypass. The patients were randomly assigned to receive intermittent renal perfusion with either 4 degrees C lactated Ringers solution (n = 86) or 4 degrees C blood (n = 86). Renal complications within 10 days of operation were stratified by renal dysfunction score (RDS). Postoperative changes in the levels of five urinary biomarkers-retinol binding protein, alpha-1 microglobulin, microalbumin, N-acetyl-beta-D-glucosaminidase, and intestinal alkaline phosphatase-were compared to assess potential differences in subclinical renal injury. RESULTS Although total ischemic times were longer in the cold blood group, unprotected ischemic times were similar between the two groups. Twenty-seven patients in the cold blood group (31%) and 21 patients in the cold crystalloid group (24%) had peak RDS >or=2 (serum creatinine >50% above baseline; P = .4). There were no differences between the cold blood and cold crystalloid groups in the incidence of early death (7/86 [8%] vs 5/86 [6%], respectively; P = .8) or renal failure requiring hemodialysis (3/86 [3%] in both groups). Changes in renal biomarker levels were also similar in the two groups. Spinal cord deficits developed in 5 patients in the cold blood group (6%); there were no such deficits in the cold crystalloid group (P = .06). CONCLUSION Cold renal perfusion during TAAA repair provides effective protection against renal injury. Using cold blood instead of cold crystalloid does not enhance renal protection.

Estimating group mortality and paraplegia rates after thoracoabdominal aortic aneurysm repair

BACKGROUND Most clinical studies regarding thoracoabdominal aortic aneurysm (TAAA) surgery are retrospective comparisons involving heterogeneous groups of patients. Risk models that evaluate susceptibility bias enhance interpretation of these intergroup comparisons. The purpose of this analysis was to derive group risk models for mortality and paraplegia after TAAA repair. METHODS Data regarding 1,220 consecutive patients undergoing TAAA repair were analyzed via multiple logistic regression with stepwise model selection. Categorical preoperative risk factors that predicted 30-day mortality and paraplegia were used to develop risk models. RESULTS Fifty-eight patients (4.8%) died within 30 days and 56 patients (4.6%) developed paraplegia or paraparesis. Predictors of mortality were rupture, renal insufficiency, symptomatic aneurysms, and Crawford extent II repairs. Extent of repair and acute presentation were predictors of paraplegia. The derived risk models estimated mortality and paraplegia rates that correlated well with actual frequencies reported in other contemporary series (regression slopes = 0.87 and 1.06, respectively). CONCLUSIONS The derived risk models accurately estimate paraplegia and mortality rates in groups of patients. Prospective model validation will be required to confirm their accuracy.

Transjugular intrahepatic portosystemic shunt for recurrent hepatic hydrothorax

For many years, pleural effusions have been recognized as a complication of cirrhosis, occurring in approximately 5.5% of patients. Recent studies have confirmed that small defects in the diaphragm allow for passage of ascitic fluid into the pleural space. Successful management of these patients is challenging, as many of the treatment options can be associated with increased morbidity. The initial treatment should focus on eliminating and preventing the recurrence of ascites with diuretics and water and salt restriction. For those patients who do not respond medically, more invasive techniques have been used including serial thoracentesis, chest tube placement, chemical pleurodesis, and peritoneovenous shunts. We present a patient with recurrent pleural effusions secondary to hepatic cirrhosis who was unsuccessfully treated medically, and subsequently treated with thoracentesis, chest tube drainage and pleurodesis, with ultimate resolution after transjugular intrahepatic portosystemic shunt placement.

The anatomical aspects of minimally invasive cardiac valve operations

Cadaveric dissections were carried out to examine the relationship of the cardiac valve structures to the surface anatomy of the chest as it relates to our approaches to minimally invasive valvular operations. The techniques of upper hemisternotomy and lower hemisternotomy as used at our institution are described.

Esophagectomy after pneumonectomy: a surgical challenge

Esophagectomy after pneumonectomy has been reported rarely, and the surgical approach presents a challenge. We report a case of a transthoracic esophagectomy in a 54-year-old man who had undergone right pneumonectomy for non-small cell lung cancer 16 years previously.

The surgeon's work in transition: should surgeons spend more time outside the hospital?

Libby Zion was an 18-year-old college student who died in a New York City emergency room in 1984. Her father, a newspaper columnist and former federal prosecutor, sued the hospital and campaigned against long working hours for residents. As a result, New York State passed the “Libby Zion Law” in 1989, limiting work hours for house officers [1]. Ever since then, events have moved steadily, albeit in fits and starts, toward a conclusion that now seems to have been inevitable. The national 80-hour workweek mandated for house officers by the Accreditation Council for Graduate Medical Education has begun, and the disruption of traditional work schedules will be dealt with more or less effectively in medical graduate training programs around the country [2]. We do not know what effect these changes will have on the profession of surgery, but most of us strongly suspect that it will not be good. At the very least, surgeons of the future are likely to have a work ethic that is different from the one we acquired during and after our training. In fact, a shift in attitude toward work seems to be well underway already. Applications to general surgical training programs have been in progressive decline over the last few years. Much of the decline seems to be related to changes in professional expectations of medical students. These students want controlled working hours and more dedicated time for family and leisure activities [3]. Perhaps the mandatory reduction in work schedule for residents will reawaken interest in surgical training. In any case, it appears that the era of the “24/7” availability of surgeons and 16 to 18 hour workdays (only 4 to 8 hours on weekend days with an occasional weekend off) may be ending and slowly fading into oblivion. Assuming that this scenario of surgery’s future is accurate, does it contain lessons for those of us still caught up in the old paradigm? Is there something to be said for or, perhaps, something to be gained from cardiothoracic surgeons joining the trend by adopting a more friendly family or personal lifestyle attitude toward the distribution of our waking hours? The question of more time for surgeons outside the hospital was debated at The Southern Thoracic Surgical Association Annual Meeting in November 2002. The topic of the debate was “The surgeon’s work in transition: surgeons should cut back on time in the hospital to spend more time with family and personal interests.” Ross Ungerleider argued the affirmative position, and Joseph Coselli argued the negative position. Their positions are presented with the assistance of co-authors in the following essays.

The role of genetic screening and prophylactic surgery in surgical oncology1

It is a fundamental principle that cancer is a genetic disease. Cancer results from the accumulation of genetic damage within the nucleus of a cell. Cancer is stably inherited during cell division so that when a cancer cell divides, both daughters are also cancer cells. Division of a progenitor cancer cell eventually results in transformation of an organ into a neoplastic phenotype. There is a large amount of evidence suggesting that in most patients cancer results from one or more acquired somatic mutations caused by chemical carcinogens or mutagens in the environment, but it is estimated that 1 of every 10 patients with breast, colon, and thyroid cancer inherits the disease by a germline mutation. Identifying the genetic mutation associated with a neoplasm can be useful to physicians in four ways: 1) to screen asymptomatic patients and possibly perform a prophylactic surgical procedure; 2) to tailor chemotherapy; 3) to suggest prognosis; and 4) to apply gene therapy. This is a collective review article, the purpose of which is to update surgeons on the current role of genetic screening for inherited breast, colon, and thyroid carcinoma in patients who already have cancer and in high-risk, asymptomatic individuals. It will also discuss indications and suggested methods of prophylactic surgery, tamoxifen chemoprevention, colonoscopy screening, and screening for associated malignancies. HISTORY OF MOLECULAR GENETICS