Peripheral vascular disease intervention in patients with end-stage renal disease: few complications in those treated with peritoneal dialysis.

ABSTRACT

Background. We assessed the results of peripheral vascular surgery in patients with end-stage renal disease (ESRD) who were being treated with peritoneal dialysis.

Methods. Sixty-seven ESRD patients on peritoneal dialysis who had peripheral vascular surgery were assessed retrospectively for preoperative risk factors, primary and secondary patency rates, and mortality. The study group had 48 proximal femoral-popliteal bypasses, 12 distal femoral-popliteal bypasses, and 7 distal femoral-tibial and/or peroneal revascularizations.

Results. Among 67 peritoneal dialysis patients, 15 deaths (22%) occurred over 68 months (mean, 14 months).

Conclusion. Patients on peritoneal dialysis had adequate patency rates and length of survival after peripheral vascular surgery when maintained on peritoneal dialysis.

IN 1995, MORE THAN 68,870 patients began treatment for end-stage renal disease (ESRD). (1) At the end of that year, a total of 257,266 patients with ESRD were alive and receiving treatment in the United States. Hypertension and diabetes mellitus are responsible for more than two thirds of renal failure cases (1); both are known risk factors for atherosclerosis and peripheral vascular occlusive disease. In up to 75% of patients with ESRD, peripheral vascular disease will develop, requiring operative intervention in potentially 200,000 cases per year. (2) Several reviews of the results of infrainguinal bypass in patients with renal failure have suggested that survival rates in patients with ESRD are decreased, with similar patency rates in those with ESRD and non-end-stage renal disease. (3-8) Long-term survival rates for patients with ESRD are 46% at 5 years and 22% at 10 years for those aged 50 to 54 years. Survival rates in diabetic and elderly patients are even lower. (2)

Several options are available for patients with ESRD. Transplant organs are scarce, and only 35% to 50% of patients with ESRD are physically and psychologically suited to transplantation. (9) Although peritoneal dialysis and hemodialysis differ in the mechanism of filtration, overall mortality rates for the two modalities are similar. Only older patients with diabetes show an increased relative risk of mortality with continuous ambulatory peritoneal dialysis (CAPD). (10) In the United States, CAPD and continuous cycling peritoneal dialysis are used for patients who want to remain independent, and for those unable to tolerate hemodialysis or in whom vascular access is difficult. (11) The purpose of our study was to evaluate peritoneal dialysis patients who had peripheral vascular surgery. Of those patients who received peritoneal dialysis, the decision to use CAPD was in response to the patient's request and based on assessment of family support and reliability, but was unrelated to specific risk factors.

MATERIALS AND METHODS

In a retrospective analysis, we studied 67 consecutive patients at one university hospital who had ESRD, were being treated with peritoneal dialysis, and had had peripheral vascular reconstruction. Patients were assigned to three categories based on the operative infrainguinal vascular reconstructive procedure. Forty-eight patients had proximal femoral-popliteal revascularization; 12 had distal femoral-popliteal bypass; and 7 had distal femoral-tibial revascularization, peroneal revascularization, or both. The indications for peripheral revascularization surgery are shown in Table 1.

The study group of 67 patients included 36 women (31 black, 5 white) and 31 men (28 black, 3 white). Fourteen of the women and 18 of the men had diabetes mellitus. Risk factors are listed in Table 2. The patients were followed up for a mean of 21 [+ or -] 3 months. All patients were ambulatory before being considered for vascular reconstruction. Smoking was not a contraindication to reconstructive surgery; no patient was refused surgery who would have benefited from it. Seven of eight patients who smoked had autogenous tissue bypass.

RESULTS

Of the 67 peritoneal dialysis patients, 36 (54%) had hypertension, 32 (48%) had diabetes mellitus, 11(16% ) had cardiac disease, and 3 (4%) had a history of cerebrovascular accident. Fifty-one (76%) of the 67 peritoneal dialysis patients used tobacco.

Of the 67 patients with ESRD on peritoneal dialysis with reconstructed peripheral vascular disease, 48 who had proximal femoral-popliteal bypass surgery had a graft patency rate of 7 to 68 months (mean, 22 months); 9 patients died at 12, 14, 19, 22, 26, 31, 32, 40, and 41 months, respectively (mean, 26.3 months). The 8 patients with less than one-half block claudication (all had some form of employment) had the greatest patency, 16 to 18 months (mean, 34 months). Their outcome was better than that of any other group. The 12 patients who had distal femoral-popliteal bypass had a patency rate of 3 to 19 months (mean, 7 months); 4 died at 11, 19, 31, and 42 months, respectively. The patency rate for the 7 patients with distal femoral-tibial revascularization, peroneal revascularization, or both was 9 to 49 months (mean, 27 months); 2 died at 4 and 9 months, respectively.

After vascular reconstructive surgery, 22% of peritoneal dialysis patients died during the 4- to 42-month follow-up period. A summary of surgical results is shown in Table 3.

After peripheral vascular surgery, concerns include degree of ambulation recovery as a measure of quality of life. In the 67 ESRD patients treated with peritoneal dialysis and vascular reconstruction, the 90-day assessment included the following findings: 44 (66%) had independent ambulation, 12 (18%) were capable of limited ambulation, 7 (10%) were transfer-independent, and 4 (6%) used wheelchairs.

The peritoneal dialysis catheter was removed and replaced in 19 of the 67 patients because of nonfunction. In only 2 of these patients was the diagnosis of peritonitis considered, treated with antibiotics, and another peritoneal catheter placed at a later date.

DISCUSSION

As the majority of the population reaches age 65, more patients will require dialysis therapy, and a greater percentage of this population will also have comorbid conditions, including peripheral vascular disease. Vascular surgeons should be well versed in the limited number of options available to those patients with both ESRD and peripheral vascular disease. The life expectancy for patients with both ESRD and peripheral vascular disease is dismal (0% to 45% over 2 years), (4-8) yet intervention can lead to a higher quality of life without additional morbidity or mortality. Patients awaiting transplant, or those who are not candidates for transplantation, are maintained on either hemodialysis or peritoneal dialysis, because patients with ESRD should progress to transplantation. An outcome comparison of peripheral vascular disease surgical patients who have been treated with different dialysis modalities has not been explored in-depth.

Although peritoneal dialysis has been shown to have a beneficial effect in patients with altered cardiac performance, it remains uncertain whether peritoneal dialysis provides a clear survival benefit over hemodialysis. (12) numerous advantages of peritoneal dialysis as opposed to hemodialysis include avoidance of disequilibrium syndrome, decreased incidence of arrhythmias, more optimal blood pressure control, slower decline in residual kidney function, improvement of anemia, absence of vascular access requirement, improved efficacy of intraperitoneal insulin therapy, and removal of [[beta].sub.2]-microglobulin and other molecular substances such as parathyroid hormone. (9) Yet, peritoneal dialysis is used by only 10% of patients with ESRD, despite changes in the Medicare ESRD program seeking to encourage reduction in treatment costs through shifts in choice of modality to home dialysis. (13)

Although peritoneal dialysis and hemodialysis have not been shown to result in definite suryival differences when compared in the past, (10,14) our results suggest a difference in these patients' condition after they have had peripheral vascular surgical intervention. Patients undergoing peripheral vascular surgery who have ESRD and are maintained on peritoneal dialysis fare better than those on hemodialysis in terms of survival and graft patency rates. (4-7) Among the 67 peritoneal dialysis patients in our study, 15 deaths (22%) occurred during 68 months (mean, 14 months).

Compared with previous reports, differences were noted in patency rates for the two groups who had proximal femoral-popliteal bypass and distal femoral-popliteal bypass. (4-7) Patients on peritoneal dialysis had improved length of survival if maintained on peritoneal dialysis and decreased mortality after peripheral vascular surgery compared with patients with ESRD who were maintained on hemodialysis. Hemodialysis patients had a significantly higher number of surgical risk factors than did the peritoneal dialysis patients. (10) Intuitively, it would seem that mortality rates would be higher for hemodialysis patients than for peritoneal dialysis patients despite surgery, because atherosis has been reported to progress more rapidly in those on hemodialysis. (3) During hemodialysis, significant hemodynamic effects occur that are not present during peritoneal dialysis: hyperkinetic circulatory effects, hypotension, exposure of blood to a foreign membrane inducing a transient inflammatory response, hypoxemia, iron overload, anemia, and electrolyte depletion.3

Hypotension is a well-known complication of hemodialysis. Hemodialysis patients also have several major volume shifts weekly and are at an increased risk for bleeding caused by systemic anticoagulation used during hemodialysis.9 These patients are at considerable risk for infection, dementia, and depression. An increased incidence of hepatitis B surface antigen exists, related to decreased immunologic integrity and an increased transfusion rate in hemodialysis patients. Elaboration of cytokines, including interleukin-l, interleukin-6, and tumor necrosis factor, occurs with exposure of blood to a foreign membrane. Control of hypertension is also more difficult in hemodialysis patients than in those on pentoneal dialysis. (15) The process of hemodialysis results in a measurable difference when compared with peritoneal dialysis in patients with ESRD who have peripheral vascular surgery.

Although not appropriate for all patients, peritoneal dialysis has numerous benefits, and for many patients on hemodialysis, it may be a more optimal treatment modality. Several factors influence the choice of dialysis modality. Although patient satisfaction is reported to be higher for those on peritoneal dialysis, physicians' preference in the United States is hemodialysis. Of patients receiving peritoneal dialysis, 68% reported that in-unit hemodialysis was discussed, whereas only 25% of those who received hemodialysis reported that CAPD was discussed. (16) Fees for hemodialysis primarily consist of physician and staff costs, whereas the bulk of the cost of peritoneal dialysis is the equipment and dialysate. Overall cost for the treatment modalities is similar: $46,000/patient-year for hemodialysis versus $41,000/patient-year for peritoneal dialysis ($16,000/patient-year for transplant patients). These figures do not include the additional expense of obtaining and maintaining hemodialysis vascular access, which has been cited as the largest single cause of morbidity among hemodialysis patients and accounts for an additional cost of more than $10,000/patient-year. (13)

CONCLUSION

Patients with coexisting ESRD and peripheral vascular disease may benefit from the use of peritoneal dialysis instead of hemodialysis.

References

(1.) USRDS Annual Report: Incidence and prevalence of ESRD. Am J Kidney Dis Suppl 1997; 30(2 Suppl 1):40-53

(2.) USRDS Annual Report: Patient mortality and survival. Am J Kidney Dis Suppl 1997; 30(2 Suppl 1):86-106

(3.) Donayre CE: Results of revascularization for peripheral arterial insufficiency in chronic renal failure patients. Semin Vasc Surg 1996;9:253-261

(4.) Sakurai T: Infrainguinal arterial reconstruction in end-stage renal disease. Cardiovasc Surg 1995; 3:46-49

(5.) Isiklar M: Infrainguinal bypass in end-stage renal disease: when is it justified? Semin Vasc Surg 1997; 10:42-48

(6.) Baele H: Infrainguinal bypass in patients with end-stage renal disease. Surgery 1995; 117:319-324

(7.) Harpavat M, Gahtan V, lerardi R, et al: Does renal failure influence infrainguinal bypass graft outcome? Am Surg 1998; 64:155-159

(8.) Lumsden AB, Besman A: Infrainguinal revascularization in end-stage renal disease. Ann Vasc Surg 1994; 8:107-112

(9.) Lazarus JM, Brenner BM: Chronic renal failure. Harrison's Principles of Internal Medicine. Fauci AV, Brawnwald E, et al (eds). New York, McGraw-Hill, 14th Ed, 1998, pp 1513-1520

(10.) Rocco MV, Flanigan MJ: Report from the 1995 Core Indicators for Peritoneal Dialysis Study Group. Am J Kidney Dis 1997; 30:165-172

(11.) USRDS Annual Report: Treatment modalities for ESRD patients. Am J Kidney Dis Suppl 1997; 30(2 Suppl 1):54-66

(12.) Maiorca R: A six-year comparison of patients and technique survivals in CAPD and HD. Kidney Int 1988; 34:518-524

(13.) USRDS Annual Report: Economic cost of ESRD, vascular access, and Medicare spending. Am J Kidney Dis Suppl 1997; 130(2 Suppl 1):160-177

(14.) Consensus Development Conference Panel: Morbidity and mortality of renal dialysis: an NIH consensus conference statement. Ann Intern Med 1994; 121:62-70

(15.) Alpert M: Continuous ambulatory dialysis and the heart. Perit Dial Int 1995; 15:6-11

(16.) USRDS Annual Report: USRDS dialysis morbidity and mortality study: wave 2. Am J Kidney Dis Suppl 1997; 30(2 Suppl 1):69-85

TABLE 1

Indication for Peripheral Vascular Surgery in Peritoneal Dialysis
Patients

                                 No. Operations
          Indication                (n = 67)

Claudication                            8
Rest pain                              41
Tissue loss                            18
Impending limb loss                    59
    (Rest pain and tissue loss)
TABLE 2

Risk Factors for Peripheral Vascular Surgery

                                    No. Patients(%)
           Risk Factor                 (n = 67)

Diabetes mellitus                       32 (49)
Cardiac disease                         11 (16)
Tobacco use                             51 (76)
Hypertension                            36 (54)
Cerebrovascular accident (history)       3 (4)
TABLE 3

Summary of Reconstructive Surgical Results in End-stage Renal Disease
Patients on Peritoneal Dialysis

                                 Type of Vascular Surgery


                                   Proximal Femoral-
Variable                            Popliteal Bypass

No. patients                               48
Graft patency duration (mo)               7-68
Average patency duration (mo)              22

                                       Type of Vascular Surgery

                                                    Distal Femoral-
                               Distal Femoral-      Tibial/Dorsalis
Variable                       Popliteal Bypass  Pedis/Peroneal Bypass

No. patients                          12                   7
Graft patency duration (mo)          9-49                3-19
Average patency duration (mo)         27                   7

KEY POINTS

* End-stage renal disease patients on peritoneal dialysis can safely and successfully undergo peripheral vascular surgery.

* There is a decreased cost of peritoneal dialysis as compared with hemodialysis.

* After vascular reconstruction, 22% of peritoneal dialysis patients died.

* The claudication group of patients had a mean bypass patency rate of 34 months.

* The patients with rest pain had a mean bypass patency rate of 22 months.