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.

Renal transplants: can acute rejection and acute tubular necrosis be differentiated with MR imaging?

Magnetic resonance (MR) imaging was used in 40 renal transplant recipients to determine whether this modality can enable distinction of acute tubular necrosis (ATN) and acute rejection by means of corticomedullary differentiation (CMD). Each patient underwent initial MR imaging after allograft renal transplantation. Twenty-nine of these 40 patients (72%) also underwent subsequent follow-up MR imaging. Seventeen studies were obtained during episodes of ATN; 12 of these studies (71%) showed poor CMD. Eleven studies were obtained during episodes of acute rejection; eight of these studies (73%) showed poor CMD. In addition, six of seven studies (86%) showing various combinations of renal disease (ATN, acute rejection, chronic rejection, and cyclosporine toxicity) also showed poor CMD. Loss of CMD is reversible after improvement of ATN and acute rejection. Because loss of CMD is a nonspecific though sensitive sign reflecting renal transplant dysfunction, MR imaging is of limited value in the differentiation of ATN from acute rejection.

Essential fatty acid depletion of renal allografts and prevention of rejection.

A central hypothesis in transplantation biology is that resident leukocytes expressing class II histocompatibility antigens may determine the immunogenicity of an organ. By means of a novel method to deplete the kidney of resident leukocytes, essential fatty acid deficiency (EFAD), this hypothesis was tested in an intact, vascular organ. Kidneys subjected to EFAD and thus depleted of resident Ia-positive macrophages survived and functioned when transplanted across a major histocompatibility antigen barrier in the absence of immunosuppression of the recipient. Control allografts were rejected promptly. Allografts from donors subjected to EFAD normalized their lipid composition and were repopulated with host macrophages by 5 days. Administration of Ia-positive cells at the time of transplantation established that the resident leukocyte depletion induced by EFAD was responsible for the protective effect. These observations may provide insights into the mechanisms underlying tissue immunogenicity and the population of normal tissues with resident leukocytes.

Extra reactivities detected in flow-cytometry-positive, CDC-negative crossmatches are definable HLA specificities.

In this preliminary study, additional reactions were detected in sera that were not found by T-AHG-CDC. The reactions had definable HLA specificities. In our laboratory, the procedures described in this article had the following relative sensitivities for detecting class I HLA alloantibody specificities: FC = B-AHG-CDC greater than T-AHG-CDC greater than B-CDC greater than T-CDC. This study supports the concept that some FC-positive crossmatches, negative by T-AHG-CDC, can be associated with reduced renal allograft survival, since many of the additional reactions detected by FC appear to be due to HLA Class I antibodies.

Effect of treatment with cyclosporine versus azathioprine on incidence and severity of cytomegalovirus infection posttransplantation.

The incidence and severity of cytomegalovirus (CMV) infection were evaluated in 24 renal transplant patients treated with steroids and cyclosporine and compared with 40 patients treated with steroids and azathioprine: 58% of patients receiving azathioprine and 33% of patients receiving cyclosporine required additional therapy with antithymocyte globulin (ATG) to treat steroid-resistant rejections. CMV antibody titers and cultures of urine and saliva were determined monthly for 4-6 months following transplant in all patients. Both the frequency of CMV infection (occurring in 58% of patients on steroids and cyclosporine and in 48% of patients on steroids and azathioprine) and its severity (21% of cyclosporine-treated patients and 22% of azathioprine-treated patients with symptoms) were similar in both groups. Use of ATG was associated with an increased incidence of CMV disease, especially for patients in the azathioprine group. Both the incidence of CMV disease, and the number of patients with symptoms in the azathioprine group were significantly lower when patients who had received ATG were excluded from analysis. When results were analyzed in just the cadaveric recipients in each group, the incidence and severity of CMV infection tended to be higher in azathioprine-treated patients compared with those maintained on cyclosporine. This could have been explained by the more frequent use of ATG in 84% of azathioprine maintained patients compared with 35% of cyclosporine-treated patients (P less than 0.002) since other factors, such as risk for CMV infection and Solumedrol dose for rejection were similar in both groups. The data demonstrate that ATG has a deleterious influence on the incidence and severity of CMV infection in renal transplant patients, even when the dosage of other immunosuppressive drugs is decreased during ATG therapy. Since patients treated with steroids and azathioprine tend to require ATG to treat steroid-resistant rejection more frequently than do patients on cyclosporine, this effect of ATG must be taken into account when evaluating CMV infection in patients on these two drug regimens.

Disseminated Mycobacterium chelonei infection following cadaveric renal transplantation: favorable response to cefoxitin.

This article describes a case of disseminated Mycobacterium chelonei infection in a renal transplant recipient. This patient, who underwent thoracic duct drainage prior to cadaveric renal transplantation, developed M chelonei bacteremia and numerous subcutaneous nodules a few weeks after transplantation. The M chelonei initially responded to amikacin and tetracycline. Because of side effects and bacterial resistance, however, these drugs had to be discontinued. Subsequent treatment with cefoxitin led to reduction in size of subcutaneous nodules, but control of the infection was not achieved until an intravascular nidus of infection at the anastomotic site of an arteriovenous fistula was removed.

Renal perfusion preservation without cannulation. Prevention of posttransplantation renal artery stenosis.

Cadaver kidneys were preserved by a technique that uses hypothermic pulsatile perfusion without cannulation of the renal arteries. This avoids the mechanical trauma that is inevitably associated with cannulation and preserves a maximum of untraumatized arterial tissue. Cannulation injury is thus eliminated as a potential cause of renal artery stenosis. Revascularization is simplified, especially when multiple renal arteries are attached to a cuff of aorta.