TiO2/Karaya Composite for Photoinactivation of Bacteria.

TiO2/Karaya composite was synthesized by the sol-gel method for the photoinactivation of pathogens. This is the first time that we have reported this composite for an antimicrobial approach. The structure, morphology, and optical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-rays (EDS), Fourier transform infrared spectroscopy (FTIR), and diffuse reflectance, and the surface area was characterized by the BET method. The XRD and EDS results showed that the TiO2/Karaya composite was successfully stabilized by the crystal structure and pore diameter distribution, indicating a composite of mesoporous nature. Furthermore, antibacterial experiments showed that the TiO2/Karaya composite under light was able to photoinactivate bacteria. Therefore, the composite is a promising candidate for inhibiting the growth of bacteria.

Airborne laser-guided imaging spectroscopy to map forest trait diversity and guide conservation.

Functional biogeography may bridge a gap between field-based biodiversity information and satellite-based Earth system studies, thereby supporting conservation plans to protect more species and their contributions to ecosystem functioning. We used airborne laser-guided imaging spectroscopy with environmental modeling to derive large-scale, multivariate forest canopy functional trait maps of the Peruvian Andes-to-Amazon biodiversity hotspot. Seven mapped canopy traits revealed functional variation in a geospatial pattern explained by geology, topography, hydrology, and climate. Clustering of canopy traits yielded a map of forest beta functional diversity for land-use analysis. Up to 53% of each mapped, functionally distinct forest presents an opportunity for new conservation action. Mapping functional diversity advances our understanding of the biosphere to conserve more biodiversity in the face of land use and climate change.

The diffusion of minimally invasive radical prostatectomy in the United States: a case study of the introduction of new surgical devices.

BACKGROUND: The diffusion of minimally invasive radical prostatectomy (MIRP) in the United States may have led to adverse patient outcomes due to rapid surgeon adoption and collective inexperience. We hypothesized that throughout the early period of minimally invasive surgery, MIRP patients had inferior outcomes as compared with those who had open radical prostatectomy (ORP). METHODS: We used the Surveillance, Epidemiology and End RESULTS-Medicare dataset and identified men who had ORP and MIRP for prostate cancer from 2003-2009. Study endpoints were receipt of subsequent cancer treatment, and evidence of postoperative voiding dysfunction, erectile dysfunction (ED) and bladder outlet obstruction. We used proportional hazards regression to estimate the impact of surgical approach on each endpoint, and included an interaction term to test for modification of the effect of surgical approach by year of surgery. RESULTS: ORP (n=5362) and MIRP (n=1852) patients differed in their clinical and demographic characteristics. Controlling for patient characteristics and surgeon volume, there was no difference in subsequent cancer treatments (hazard ratio (HR) 0.89, 95% confidence interval (CI) 0.76-1.05), although MIRP was associated with a higher risk of voiding dysfunction (HR 1.31, 95% CI 1.20-1.43) and ED (HR 1.43, 95% CI 1.31-1.56), but a lower risk of bladder outlet obstruction (HR 0.86, 95% CI 0.75-0.97). There was no interaction between approach and year for any outcome. When stratifying the analysis by year, MIRP consistently had higher rates of ED and voiding dysfunction with no substantial improvement over time. CONCLUSIONS: MIRP patients had adverse urinary and sexual outcomes throughout the diffusion of minimally invasive surgery. This may have been a result of the rapid adoption of robotic surgery with inadequate surgeon preparedness.

Spurious elevation of serum PSA after curative treatment for prostate cancer: clinical consequences and the role of heterophilic antibodies.

BACKGROUND: Various interferences can cause spurious results for common laboratory tests. Although rare, heterophilic antibodies may produce false elevations in PSA that could prompt unnecessary therapy in men previously treated for prostate cancer. The aim of this study was to determine the prevalence of small, spurious PSA elevations, and the role of heterophilic antibodies. METHODS: Phase I: all PSA tests drawn and measured between 27 October 2008 and 26 October 2010 at Vanderbilt University Medical Center were analyzed (n=17 133). Patients who had been treated for prostate cancer with PSA values that changed from undetectable to detectable were evaluated. Phase II: patients with a detectable PSA ≤0.5 ng ml(-1) measured between 24 October 2010 and 19 January 2011 were studied prospectively (n=1288). If any patient had a previously undetectable PSA value, their serum was tested for heterophilic antibody interference. RESULTS: Phase I: 11 men had a spuriously elevated PSA after curative treatment for prostate cancer (0.3%). Mean time to PSA elevation was 3.4±5.5 years, and mean elevation in PSA was 0.33±0.28 ng ml(-1). Each patient's PSA was undetectable after being repeated, and no patient went on to unnecessary treatment. Phase II: 10 men had a newly detectable PSA, 9 of whom had a history of prostate cancer. Each tested negative for interfering heterophilic antibodies when their PSA test was repeated with a heterophilic antibody-blocking reagent. CONCLUSIONS: In a large cohort, we estimate the prevalence of spuriously elevated PSA values in our population to be 0.3%. No patient with a prostate cancer history was subjected to unnecessary diagnostic evaluation or treatment. On prospective evaluation of PSA conversion to low detectable levels, no patient had evidence of interfering heterophilic antibodies. When using PSA for post-treatment surveillance, it is crucial to confirm all concerning values and consider the presence of a spurious elevation in PSA if the value does not correlate with the clinical scenario.

Effects of surgical or banding castration on stress responses and behaviour of bulls.

OBJECTIVE: To compare the effects of surgical and latex banding methods of castration in 14- and 9-month-old bulls. DESIGN: Two randomised, controlled experiments. PROCEDURE: In Experiment 1, following administration of local anaesthetic, 14-month-old bulls were castrated by either surgical or banding methods, or left entire. Behavioural, plasma cortisol, plasma haptoglobin and bodyweight responses were recorded. A group of steers from the same mob was used as an additional comparison for bodyweight data. In Experiment 2, following administration of local anaesthetic, 9-month-old bulls were castrated by either surgical or banding methods and cortisol, haptoglobin and bodyweight responses were recorded. Entire bulls from the same group were used as an additional comparison for bodyweight data. RESULTS: In Experiment 1, surgical castrates exhibited more leg stamping and tail swishing than banded or entire animals in the hours after castration. Surgical castrates in both experiments also showed an increase in plasma haptoglobin, which resolved after 4 days. Plasma cortisol was generally not affected by castration. Surgical castrates grew more slowly than entire bulls, but faster than banded animals, in the 56 days after treatment. In Experiment 1, after 56 days, the bodyweights of surgical and banded castrates were not different from the bodyweights of the steers. Fourteen-month-old banded cattle developed persistent wounds above the latex band which remained for several weeks after scrotal dehiscence, but this did not occur in the 9-month-old animals. CONCLUSION: The banding procedure produced fewer acute effects, but a greater suppression of growth than surgical castration and induced prolonged wound formation in the older age group, suggesting that this procedure may not be as suitable for yearling cattle.

A national survey of policies on disclosure of conflicts of interest in biomedical research.

BACKGROUND: Conflicts of interest pose a threat to the integrity of scientific research. The current regulations of the U.S. Public Health Service and the National Science Foundation require that medical schools and other research institutions report the existence of conflicts of interest to the funding agency but allow the institutions to manage conflicts internally. The regulations do not specify how to do so. METHODS: We surveyed all medical schools (127) and other research institutions (170) that received more than $5 million in total grants annually from the National Institutes of Health or the National Science Foundation; 48 journals in basic science and clinical medicine; and 17 federal agencies in order to analyze their policies on conflicts of interest. RESULTS: Of the 297 institutions, 250 (84 percent) responded by March 2000, as did 47 of the 48 journals and 16 of the 17 federal agencies. Fifteen of the 250 institutions (6 percent)--5 medical schools and 10 other research institutions--reported that they had no policy on conflicts of interest. Among the institutions that had policies, there was marked variation in the definition and management of conflicts. Ninety-one percent had policies that adhered to the federal threshold for disclosure ($10,000 in annual income or equity in a relevant company or 5 percent ownership), and 9 percent had policies that exceeded the federal guidelines. Only 8 percent had policies requiring disclosure to funding agencies, only 7 percent had such policies regarding journals, and only 1 percent had policies requiring the disclosure of information to the relevant institutional review boards or to research subjects. Twenty journals (43 percent) reported that they had policies requiring disclosure of conflicts of interest. Only four federal agencies had policies that explicitly addressed conflicts of interest in extramural research, and all but one of the agencies relied primarily on institutional discretion. CONCLUSIONS: There is substantial variation among policies on conflicts of interest at medical schools and other research institutions. This variation, combined with the fact that many scientific journals and funding agencies do not require disclosure of conflicts of interest, suggests that the current standards may not be adequate to maintain a high level of scientific integrity.

Tobacco withdrawal signs and symptoms among women with and without a history of depression.

A past history of depression is associated with a decreased likelihood of quitting smoking. Tobacco withdrawal may be a mechanism through which depression history impedes smoking cessation. This research examined the influence of depression history on unmedicated tobacco withdrawal signs (polysomnographic measures of sleep) and symptoms (self-reported urge, negative affect, hunger, and sleep) among women (N= 13). Depression history was associated with differential withdrawal-induced changes in several REM sleep parameters. Self-report and other polysomnography (sleep fragmentation, slow-wave sleep) measures displayed statistically significant withdrawal effects but did not discriminate between depression history groups. These results suggest that REM sleep parameters may be sensitive to differential tobacco withdrawal responses that are not readily apparent through self-reported symptoms.

E7-transduced human breast epithelial cells show partial differentiation in three-dimensional culture.

Disruption of the retinoblastoma (RB) tumor suppressor pathway is a common and important event in breast carcinogenesis. To examine the role of the retinoblastoma protein (pRB) in this process, we created human mammary epithelial cells (HMEC) deficient for pRB by infecting primary outgrowth from breast organoids with the human papillomavirus type 16 (HPV16) E7 gene. HPV16 E7 binds to and inactivates pRB and also causes a significant down-regulation of the protein. Culturing normal HMEC in a reconstituted basement membrane (rBM) provides a correct environment and signaling cues for the formation of differentiated, acini-like structures. When cultured in this rBM, HMEC+E7 were found to respond morphologically as normal HMEC and form acinar structures. In contrast to normal HMEC, many of the cells within the HMEC+E7 structures were not growth arrested, as determined by a 5-bromo-2'-deoxyuridine incorporation assay. pRB deficiency did not affect polarization of these structures, as indicated by the normal localization of the cell-cell adhesion marker E-cadherin and the basal deposition of a collagen IV membrane. However, in HMEC+E7 acini, we were unable to detect by immunofluorescence microscopy the milk protein lactoferrin or cytokeratin 19, both markers of differentiation expressed in the normal HMEC structures. These data suggest that loss of RB in vivo would compromise differentiation, predisposing these cells to future tumor-promoting actions.

Comparative evaluation of two models for estimating sample sizes for tests on trends across repeated measurements.

Two equations for calculating sample sizes that are required for power in testing differences in rates of change in repeated measurement designs have been presented by different authors. One equation provides support for the conclusion that increased frequency of measurements across a treatment period of fixed duration enhances power of the tests. The other equation supports the counterintuitive conclusion that increased frequency of measurements actually tends to decrease power in the presence of realistic serial dependencies in the data. Monte Carlo methods confirm that the equation providing support for the latter conclusion is accurate, whereas the alternative equation tends to underestimate sample sizes required for power in testing differences in slopes of regression lines fitted to changes in the repeated measurements across time when symmetry is absent from the covariance structure.

Spontaneous closure of selected iatrogenic pseudoaneurysms and arteriovenous fistulae.

PURPOSE: We report our approach to the management of postcatheterization femoral artery pseudoaneurysms and arteriovenous fistulae in an attempt to determine the frequency of spontaneous resolution of selected lesions. METHODS: We studied 196 pseudoaneurysms, 81 arteriovenous fistulae, and 9 combined lesions that were identified by duplex scan. Indications for immediate surgical repair included pseudoaneurysm greater than 3 cm, enlarging hematoma, pain, groin infection, nerve compression, limb ischemia, concomitant surgical procedure, and patient refusal or inability to comply with follow-up. All other lesions were observed. RESULTS: One hundred thirty-nine patients underwent prompt surgical repair, and 147 patients were initially managed without operation. There were no limb-threatening complications associated with nonoperative management in this subset of patients. Eighty-six percent of the lesions being observed resolved spontaneously within a mean of 23 days, whereas 14% required surgical closure for a variety of reasons (at a mean of 111 days after the initial diagnosis). There was no statistically significant difference in the rate of spontaneous pseudoaneurysm closure (89%) as opposed to fistulae (81%) (p < 0.17). By life-table analysis, 90% of selected pseudoaneurysms had resolved by 2 months. Patients selected for observation underwent an average of 2.6 duplex scans per patient versus 1.4 scans per patient for those treated with immediate surgery (p < 0.01). CONCLUSION: The natural history of stable pseudoaneurysms and arteriovenous fistulae is benign and frequently results in spontaneous resolution, which allows properly selected patients to be managed without operation.

Objective tinnitus resulting from internal carotid artery stenosis.

Objective tinnitus represents sound wave energy that, by definition, may be heard or recorded by an examiner. It may occur as a result of either muscular contraction or turbulent blood flow. We report two cases of vascular objective tinnitus resulting from internal carotid artery stenosis. The first patient, a 74-year-old man, underwent ligation of the right internal carotid artery because of the distal extent of atherosclerosis. The second patient, a 75-year-old man, underwent a right carotid endarterectomy. Both patients noted complete relief of their tinnitus. The spectrum of vascular causes and treatment options are reviewed.

Behavioral and pharmacologic approaches to smoking cessation.

Cigarette smoking continues to be the single, most preventable cause of death and disability in the United States. For individuals who have cancer, continuing to smoke negatively impacts their treatment, survival, and risk for second primary tumors. This review of behavioral and pharmacological approaches to smoking cessation focuses on the recent comprehensive review of cessation interventions by the Agency for Health Care Policy and Research (AHCPR), as well as on new developments in the field. An intervention model is outlined that provides oncologists with a brief and easily implemented method of systematically treating patients who smoke. By assessing patient smoking status, advising smoking patients to quit, and proactively assisting their patients in quitting, oncologists can significantly influence patient health and fulfill their professional and ethical responsibility to address this life-threatening behavior.

Revascularization of the solitary kidney: a challenging problem in a high risk population.

BACKGROUND: Patients with significant atherosclerotic stenosis involving the artery to a solitary functioning kidney present a clinical challenge. METHODS: From August 1987 through August 1995, 35 of these patients (average age, 68.4 +/- 6.9 years) were treated. Comorbid conditions included previous myocardial infarction in 23% of the patients, congestive heart failure (CHF) in 34%, chronic obstructive pulmonary disease in 20%, and diabetes in 20%. The average creatinine level of the patients was 2.5 +/- 1.5 mg/dl. Indications for revascularization were hypertension in 86%, hypertensive crisis with CHF in 17%, and renal insufficiency in 69%. Procedures performed included 19 extra-anatomic bypasses, 8 concomitant with infrarenal aortic reconstruction and 2 concomitant with thoracoabdominal aortic aneurysm repair; 1 visceral segment endarterectomy; 1 renal artery endarterectomy with reimplantation; I superior mesenteric to renal artery bypass; 1 aortorenal bypass; and 2 percutaneous angioplasties with staged nephrectomies. RESULTS: At discharge, 91% of patients had stable or improved renal function with an average creatinine level of 1.7 +/- 0.8 mg/dl. Hypertension was cured or improved in 85%. Perioperative mortality was 6%, and major morbidity was 43%, including the need for permanent (9%) and temporary (9%) dialysis, respiratory insufficiency (18%), two early reoperations, six cardiac complications, one case of gastrointestinal bleeding, and one stroke. In the follow-up period (mean duration, 39.2 months), survival has been 73%, and no additional patients have required dialysis. CONCLUSIONS: Although significant perioperative morbidity exists in this high risk population, the long-term preservation of renal function and improvement in hypertension make solitary renal revascularization worthwhile.

Arachidonic acid metabolism in intestinal hypothermic preservation injury.

The effect of hypothermic intestinal ischemia and short-term reperfusion on mucosal arachidonic acid metabolism was studied in a dog model of intestinal preservation injury. Canine intestinal segments were flushed with cold Collins solution, cold stored (4 degrees C) for either 24 or 48 h, and subsequently reperfused in the donor for 1 h. Samples of intestinal mucosa obtained before ischemia, after the ischemia period, and after the reperfusion period were placed into tissue culture, and arachidonic acid metabolites were measured in the tissue incubation media. Prostaglandin E2 (PGE2) and prostacyclin (PGI2) production significantly increased after 24 h of cold ischemia and after 1 h of reperfusion, respectively. Intestines cold stored for 48 h and after 1 h of reperfusion produced significantly elevated quantities of thromboxane B2, PGI2, PGE2, and leukotriene B4, relative to the production rates from nonischemic control tissue or tissue subjected to 48 h of hypothermic ischemia without reperfusion. Mucosal production of thiol ether leukotrienes (LTC4, LTD4, LTE4) was not altered by ischemia or reperfusion at any time of cold ischemia. The synthesis of the lipoxygenase product 12-hydroxyeicosatetraenoic acid (12-HETE) was not altered by hypothermic ischemia or reperfusion, but this arachidonate metabolite was produced by small intestinal mucosa in the greatest quantities. Specifically, nanogram quantities of 12-HETE were produced by intestinal mucosa compared to picogram quantities of the other metabolites measured. Significant synthesis of the delta lactone derivative of 5-hydroxyeicosatetraenoic acid was detected by HPLC in many tissue samples undergoing 48 h of ischemia and reperfusion, relative to nonischemic tissue samples. In conclusion, significant increases in arachidonate cyclooxygenase and lipoxygenase metabolites have been identified in intestinal mucosa subjected to long-term hypothermic ischemia and short-term reperfusion. Synthesis of these products increases with the duration of cold ischemia and may play a role in intestinal preservation injury.

Intraoperative salvage in patients undergoing elective abdominal aortic aneurysm repair: an analysis of cost and benefit.

PURPOSE: Although autologous blood procurement has become a standard of care in elective surgery, recent studies have questioned its cost-effectiveness. We therefore reviewed our 3-year experience with intraoperative cell salvage in patients who underwent elective abdominal aortic aneurysm repair. METHODS: A 3-year retrospective chart review of elective abdominal aortic aneurysm (infrarenal and suprarenal) repair was performed. Transthoracic repairs were excluded. RESULTS: Estimated blood lost was 1748 +/- 1236 ml, or 35% of baseline blood volume (5012 +/- 689 ml). Overall, 164 (89%) received red blood cell (RBC) transfusions (3.5 +/- 2.0 U/patient). The cost per patient for cell salvage was $315 +/- $97, representing 31% of all RBC costs and 24% of total blood component costs. Mean salvage volume infused was 578 +/- 600 ml; at a mean hematocrit level of 55.7% the RBC volume infused from salvage during surgery was 313 +/- 328 ml (representing 27% of total RBC volume lost during the hospital stay). This mean RBC volume salvaged represented the equivalent of 1.6 blood bank RBC units. The mean blood bank costs saved by using cell salvage was $248, or 79% of the $315 actually spent for salvage. We found no decrease in percentage of patients undergoing transfusion until salvage volumes that were infused exceeded 750 ml, or the equivalent of two blood bank units; all of these patients who benefitted had estimated blood lost > or = 1000 ml. CONCLUSIONS: We conclude that use of intraoperative cell salvage was most beneficial for patients who had estimated blood loss greater than or equal to 1000 ml and cell salvage volumes infused greater than or equal to 750 ml. Patients who are estimated to lose less than 1000 ml receive little benefit yet incur substantial costs from intraoperative cell salvage.

Femoropopliteal bypass for claudication: vein vs. PTFE.

The vascular graft of choice for femoropopliteal bypass in patients with intolerable claudication is controversial. We retrospectively reviewed our experience with 239 patients suffering from claudication secondary to superficial femoral artery obstruction. Femoropopliteal reconstruction was performed with saphenous vein to the below-knee popliteal artery in 66 patients (BK-vein). Polytetrafluoroethylene (PTFE) was used in 128 patients as a bypass graft to the above-knee popliteal artery (AK-PTFE) and 45 patients had a PTFE graft to the below-knee popliteal artery (BK-PTFE). All patients were enrolled in a postoperative graft surveillance program with graft revision when appropriate. There was one perioperative death (0.4%). Primary patency at 5 years for AK-PTFE, BK-PTFE, and BK-vein was 58.0%, and 60.3%, respectively, and was not significantly different among the graft groups. Graft revision for failed/failing grafts resulted in 5-year secondary patency rates of 79.2% (AK-PTFE), 73.3% (BK-PTFE), and 74.4% (BK-vein). These secondary patency rates were not statistically different. Eventual conversion to a vein graft in patients initially treated with PTFE maximized patency in the femoropopliteal segment with 5-year patency rates of 84.6% and 93.0% for the AK-PTFE and BK-PTFE graft groups, respectively. Major leg amputation was necessary during the entire course of the study in eight (3.3%) patients. We conclude that long-term patency rates for femoropopliteal bypass in patients with intolerable claudication are similar for PTFE and autologous saphenous vein grafts.

Donor-specific transfusions have long-term beneficial effects for human renal allografts.

From April, 1980 to November, 1988, 163 one or two haplotype-mismatch living related (LR) or living unrelated (LUR) potential renal transplant recipients received three 200 ml aliquots of donor specific transfusion (DST) at biweekly intervals with concomitant azathioprine (2 mg/kg/day). Following transplantation, only prednisone and azathioprine were given for immunosuppression. The results for the DST group are compared with those for HLA identical living recipients (57 patients) transplanted during this same interval (1980-1988). Comparison is also made with a group of one or two haplotype-mismatched living donor recipients (54 patients) not treated with DST but with triple drug therapy (prednisone, azathioprine, cyclosporine) and antithymocyte globulin (ATG) or OKT-3 induction. Permanent T cell crossmatch sensitization occurred in 11 of 163 patients (7%). Successful DST donor transplants were performed between 121 one HLA haplotype-mismatched, 14 two HLA haplotype-mismatched LR, and 7 two haplotype-mismatched LUR pairs. Actual one- and five-year graft survivals were 94%, 100%, 100%, and 72%, 85%, and 71%, respectively, for these three subgroups of DST treated patients. The graft survival for all DST pretreated recipients at one, five, and ten years was comparable to the HLA-identical group (94%, 79%, 64% vs. 91%, 80% and 77%). At a mean follow-up of 10 1/2 years, 54% (80 patients) of the entire group of 147 patients transplanted after DST have functioning transplants with a mean serum creatinine of 1.7 mg/dl. Fifteen percent of DST patients (21 patients) died with a functioning graft 2 to 132 months after transplantation, 26% (37 patients) rejected the DST graft after 1 to 128 months, and 6% (9 patients) were lost for nonimmunological reasons. No lymphoproliferative disease developed in the DST group and the incidence of cytomegalovirus sepsis was only 2% (3 patients). The long-term beneficial effects of DST on renal allograft survival and function and the lower incidence of the complications of nonspecific immunosuppression should encourage increased utilization of DST in renal transplantation.

Limb salvage and patency after aortic reconstruction in younger patients.

PURPOSE: The purpose of this report was to compare patient characteristics, treatment, and outcome in younger and older patients with aortoiliac occlusive disease. METHODS: The medical records of 56 patients < or = 50 years of age (Group < or = 50) were retrospectively reviewed and compared to the records of 128 patients > or = 60 years of age (Group > or = 60). All patients were examined and treated between April 1987 and April 1994. Postoperatively, they were enrolled in a vascular laboratory surveillance program to serially monitor the status of the vascular reconstruction. Follow-up averaged more than 3 years in both groups and was available on greater than 90% of patients. RESULTS: Patients in Group < or = 50 had a higher incidence of smoking (68% versus 51%) and a lower incidence of hypertension (29% versus 50%) than patients in group > or = 60 (smoking P = 0.03, hypertension P = 0.007). No other significant differences were noted among cardiovascular risk factors. Preoperative indications for surgery were similar among patients in both groups. An aortoiliac endarterectomy was more commonly used to revascularize the lower extremities in younger patients than in their older counterparts (23% versus 7%, P = 0.002). Graft revisions were more frequently necessary after aortic reconstruction in Group < or = 50 than in Group > or = 60 (29% versus 8%, P = 0.0003); however patency rates computed by life table analysis were not significantly different. The primary patencies for Group < or = 50 and Group > or = 60 at 5 years were 64% and 67%, respectively; their secondary patency rates at 5 years were 84% and 89%, respectively. No significant difference was found in major limb amputation (8% in Group < or = 50 versus 5% in Group > or = 60, P = 0.46). We conclude that aortoiliac reconstruction for occlusive disease can be performed with similar secondary patency and amputation rates in young and old patients. However, close postoperative surveillance and frequent surgical revision are necessary to maintain patency and minimize amputation.

Transabdominal versus retroperitoneal incision for abdominal aortic surgery: report of a prospective randomized trial.

PURPOSE: The purpose of this study was to perform a randomized, prospective trial that compares the transabdominal with the retroperitoneal approach to the aorta for routine infrarenal aortic reconstruction. METHODS: From August 1990 through November 1993, patients undergoing surgery for abdominal aortic aneurysm (AAA) disease or aortoiliac occlusive disease (AIOD) were asked to participate in a randomized trial comparing the transabdominal incision (TAI) to the retroperitoneal incision (RPI) for aortic surgery. One hundred forty-five patients were randomized, with 75 (41 with AAA and 34 with AIOD) in the TAI group and 70 (40 with AAA and 30 with AIOD) in the RPI group. There were no significant differences between the groups in terms of age, sex, postoperative pain control (epidural vs patient-controlled analgesia), or comorbid conditions, except for a higher incidence of chronic obstructive pulmonary disease in the TAI group (21 vs 8 patients). RESULTS: The incidence of intraoperative complications was similar for both groups. After surgery, the incidence of prolonged ileus (p = 0.013) and small bowel obstruction (p = 0.05) was higher in the TAI group. Overall, the RPI group had significantly fewer complications (p < 0.0001). The overall postoperative mortality rate (two deaths) was 1.4%, with both occurring in the TAI group (p = 0.507). The RPI group also had significantly shorter stays in the intensive care unit (p = 0.006), a trend toward shorter hospitalization (p = 0.10), lower total hospital charges (p = 0.019), and lower total hospital costs (p = 0.017). There was no difference in pulmonary complications (p = 0.71). In long-term follow-up (mean 23 months), the RPI group reported more incisional pain (p = 0.056), but no difference was found in incisional hernias or bulges (p = 0.297). CONCLUSIONS: We conclude that the RPI approach for abdominal aortic surgery is associated with fewer postoperative complications, shorter stays in the hospital and intensive care unit, and lower cost. There is, however, an increase in long-term incisional pain. Current methods of postoperative pain control seem to decrease the incidence of pulmonary complications.