Blayne A. Standage

Percutaneous Transluminal Angioplasty versus Endovascular Stent Placement in the Treatment of Venous Stenoses in Patients Undergoing Hemodialysis: Intermediate Results

PURPOSE This report describes intermediate findings from an ongoing prospective randomized trial comparing the results of percutaneous transluminal angioplasty (PTA) with results of endovascular stent placement in patients undergoing hemodialysis. PATIENTS AND METHODS Among 87 consecutive patients with venous stenoses or occlusions, 47 (54%) were treated with PTA alone and 40 (46%) were treated with PTA and stent placement. RESULTS For peripheral sites, the primary patency rates for PTA at 60, 180, and 360 days were 55%, 31%, and 10%, respectively, and for stents were 36%, 27%, and 11%, respectively (P = .6528). The secondary patency rates for PTA at 60, 180, and 360 days were 94%, 80%, and 71%, respectively, and for stents were 73%, 64%, and 64%, respectively (P = .1677). For central sites, the primary patency rates for PTA at 60, 180, and 360 days were 81%, 23%, and 12%, respectively, and for stents were 67%, 11%, and 11%, respectively (P = .4595). The secondary patency rates for PTA were 100% at each interval, and for stents were 100%, 89%, and 78%, respectively (P = .5408). CONCLUSION Intermediate results suggest that, overall, there is no difference in the patency rates for peripheral venous stenoses in dialysis patients treated with PTA or PTA and endovascular stent placement. At this time, the numbers of patients are too small to conclude if certain sites such as larger central veins will respond better to one treatment or the other.

Long-term patency of polytetrafluoroethylene graft fistulas.

Polytetrafluoroethylene grafts have been the mainstay for hemoaccess at our dialysis unit since 1976. Of 528 grafts placed in the forearm, 81 were evaluated for long-term patency and complication rates. When appropriate diagnostic studies and clinical signs delineate the cause of graft problems, a variety of surgical techniques can be used to maintain graft patency. The overall patency rate was 81 percent at 4.47 years. There were 3.5 complications per graft and 1 procedure per 1.25 years of follow-up. Over two thirds of the grafts had minimal complications and showed a 95 percent patency rate at 4.76 years. Impra grafts seemed to fare better than Gore-tex grafts, but their patency and duration were similar. Polytetrafluoroethylene grafts are easy to use, easy to revise and repair, have a long shelf life, and can withstand repeated dialysis access for many years.

Thrombolysis Versus Thrombectomy for Occluded Hemodyalisis Grafts

Graft thrombosis is the most frequent complication of polytetrafluoroethylene grafts for hemodialysis. Many of these patients arrive at the dialysis unit with fluid and metabolic abnormalities that require prompt dialysis. Rapid declotting of the graft is important to avoid having to create temporary access. Thrombolysis with urokinase has been evaluated by recent retrospective studies and found to be successful in 60% to 90% of cases. Our prospective, randomized trial was initiated to compare thrombolysis with standard surgical thrombectomy; and to evaluate the safety, effectiveness, efficiency, and durability of these modalities. In this study, 15 patients underwent thrombolysis and 16 had thrombectomy. The success rate was 67% for the thrombolysis group compared with 94% for the surgical group. Patency rates were similar for both modalities, but the complication rates were higher and the time to completion longer with thrombolysis. Although both treatments can be used successfully, surgical thrombectomy remains the optimal choice for treating occluded dialysis grafts.

Improving the outcome in gallstone ileus.

A 32 year retrospective review of 24 cases of gallstone ileus from the hospitals of Oregon Health Sciences University has been presented. Nineteen patients (79 percent) were female and 18 (75 percent) were more than 70 years of age. Fifty-four percent of the patients had a correct preoperative diagnosis that correlated well with the roentgenographic findings. Enterolithotomy was the most frequently employed operation, and cholecystoduodenal fistulas were positively identified in 61 percent of the patients. Most obstructions occurred in the distal ileum (48 percent). Wound infections occurred in six patients (26 percent), and there were three deaths for a mortality rate of 13 percent. Of note, the incidence of wound infections and mortality is found to be decreasing. This is related to the more frequent use of prophylactic antibiotics. The controversy regarding performing an enterolithotomy alone versus a one stage procedure has been reviewed and several interesting and atypical cases have been briefly discussed.

The rational use of computed tomography scans in the diagnosis of appendicitis

BACKGROUND Recently, limited abdominal computed tomography (CT) scans have been reported (Rao, New England Journal of Medicine, 1998) to have accuracy as high as 98%. We compare our hospitals CT accuracy ordered by emergency room (ER) physicians with that of experienced surgeons provided only with the ER history and physical examination in the evaluation of appendicitis. METHODS All charts of patients 16 years or older with limited CT scans ordered by ER from January 1, 1996, through February 28, 1998, were reviewed. CT scans ordered when appendicitis was not in the differential were excluded from analysis. Pathology and clinical follow-up were criterion standards. Four surgeons reviewed ER history and physical and placed them into one of three categories: appendectomy, observe to rule out appendicitis, or discharge with follow-up (included admitting to another service or treating for another disorder). RESULTS A total of 526 charts were reviewed; 129 met the criteria for the study. The accuracy of CT scans as used by our ER was not as high as reported in the literature. In addition, surgeon accuracy approached that of the CT scan even without the ability to evaluate the patients in person. Noncontrast CTs were ordered before surgical evaluation in contrast to the Rao protocol, likely reducing their accuracy. CONCLUSIONS Ordering CT scans to evaluate for appendicitis prior to surgical evaluation is of limited value.

Outcome and sepsis after splenectomy in adults

Of 277 splenectomies performed over 10 years, 24.2 percent were incidental. Operative mortality in this group was 14.9 percent, which is higher than that encountered after splenectomy for any other indication. A majority of the deaths were from septic causes, and infectious complications accounted for most of the morbidity as well. This finding is in marked contrast to the paucity of infectious morbidity and mortality in patients with all other splenectomies. Of the 251 patients who survived these operations, follow-up was available on 175. Twenty-six had received Pneumovax, and 4 of these patients died, none from infectious causes. There were 20 septic deaths among the 149 unvaccinated patients, including 3 cases of fulminant pneumococcal sepsis.

Acute transanal evisceration of the small bowel: report of a case and review of the literature.

We report a patient who presented with rectal rupture and transanal evisceration, a rare entity with only 52 cases previously described in the world literature. Our case is the first to implicate sheer stress on the anterior rectum caused by postoperative adhesions as the major etiologic contributing feature. Moreover, this case is the third reported with chronic constipation without rectal prolapse as an additional preexisting contributory condition. A summary of the medical literature including etiology, treatment, and outcomes is presented.

Does the use of erythropoietin in hemodialysis patients increase dialysis graft thrombosis rates

Erythropoietin (EPO) is highly efficacious in the treatment of the anemia of chronic renal failure. Evidence for a reported serious side effect, increased dialysis graft thrombosis, is equivocal. Sixty-four hemodialysis patients utilizing polytetrafluoroethylene (PTFE) grafts were treated with EPO. The patients served as their own historical controls. There were 1.188 thrombectomies and 0.222 mechanical problems per 1,000 patient-days prior to the initiation of EPO treatment. With EPO, the values were 0.656 and 0.222, respectively. Patients were separated into low-, medium-, and high-dose EPO groups and analyzed within groups for the effect of EPO and between groups for a dose-dependent response. According to an analysis of variance procedure, there was no statistically significant differences between the groups, which suggests that EPO is not thrombogenic to dialysis grafts.

Repeat parathyroid operation associated with renal disease.

One hundred ten patients who had undergone operation for secondary and tertiary hyperparathyroidism have been described. Ninety patients had secondary disease and 20 patients had tertiary disease after renal transplantation. From these two groups, 18 patients had repeat operations for control of recurrent or persistent disease. The incidence of repeat operations was 14 percent. Causes were graft-dependent hyperparathyroidism, supernumerary glands in the neck or mediastinum, and incomplete identification of glands in the neck. The most important risk factor is continued long-term dialysis in functionally anephric patients. We recommend that patients with hyperparathyroidism associated with chronic renal failure undergo total parathyroidectomy with autotransplantation. If repeat operation is necessary, a reduction in glandular mass with autotransplantation is preferred. In selected patients, total parathyroidectomy can be considered because of the increased risk of aluminum bone disease.

Delayed type hypersensitivity to gangliosides in the Lewis rat

Systematic study of the immunologic properties of gangliosides has been hampered by the lack of a suitable assay. In this study, significant delayed type hypersensitivity reactions to gangliosides were observed in Lewis rats immunized with whole guinea pig spinal cord (GP-SC) in complete Freunds adjuvant (CFA). The reaction was manifested by an increase in ear thickness after intradermal injection of a mixture of gangliosides and methylated bovine serum albumin (mBSA). No responses were observed to either gangliosides or mBSA alone. The reaction to gangliosides increased after immunization, persisted for 48 h, and was characterized by perivascular infiltration of mononuclear cells. Further evidence for a cellular response was demonstrated by the transfer of ganglioside-specific ear swelling by cultured spleen cells. The response to gangliosides was not due to contamination with myelin basic protein (BP) since no reaction to gangliosides was observed in GP-BP/CFA-immunized rats, and no reaction to BP was observed in ganglioside/CFA-immunized rats. In BP-immunized rats, responsiveness to BP persisted after recovery from clinical EAE for at least 60 days. However, no response to gangliosides was observed in BP-immunized animals after recovery from clinical EAE, suggesting the lack of autosensitization to gangliosides due to the disease process itself.