Perspectives in Circulation Today
Renal Failure, PVD and End-Diastolic Boot Therapy
Can legs liked that of this hemodialysis patient be saved?
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This 75 year old California female hemodialysis patient (with a history of type 2 diabetes) had a fall calling attention to her foot when multiple foot lesions and ischemic skin changes were noted. Doppler and MRA studies showed no obvious targets for bypass surgery, which the vascular surgeon allowed angiograms would be necessary to rule out. The surgeon went on to explain that it was unlikely a successful bypass could be done and that leg amputation would likely be required in the future. The family sought an alternate form of treatment and found their way to Victorville where she had 6 or 8 Miniboot treatments given twice a week. Noting some benefit, they acquired their own Circulator Boot equipment. The pictures show pigment across the instep of both feet due to the pressure of tight footwear. The dark spot on the anterior ankle marks the site of an infected ulcer which was debrided to allow draining; it healed rapidly once she was booted daily with her own boot. Likewise, the crusts in the skinfold under the distal IP joint of the second toe healed after it was debrided releasing lots of pus. A small sore on her fifth toe healed without debridements. The infection and ulcer beneath her first toenail has been slower to respond but made progress since the nail was cut back and the area unroofed. She remains in good spirits free of cardiorespiratory symptoms and leg swelling. She is making some urine and is perhaps too ambulatory.
She has dialysis three days a week, cleans house, does the cooking and enjoys visiting her sisters. The home treatment program has varied with circumstances and has included an initial cleansing foot soak in concentrated Sea Soak, local antibiotic injections to infected areas (once daily) and Miniboot treatments (2-3 times a day) with her foot immersed in dilute Sea Soaks and antibiotics. Recently, she has tried several mist treatments to her toe.
This lady is interesting in that the bulk of her care has been provided by dedicated family members. Click here for a list of patients with renal failure who have benefited from therapy with the Circulator Boot in (1) healing difficult foot lesions and avoiding amputations; (2) improving their cardiac status; and/or (3) improving renal function and/or delaying need for dialysis. And click here for reversal of congestive heart failure and septic shock also.
What is the outlook for ESR patients with PVD?
Among persons whose renal failure was attributed to diabetic nephropathy, Medicare data showed that the rates of lower limb amputation in 1991 and 1994 were 11.8 and 13.8 per 100 person years, respectively. The rate among diabetic persons with ESRD was 10 times greater than among the diabetic population at large. Two-thirds died within two years following the first amputation.(Eggers 1999). Among patients in our VA hospitals, the presence of diabetic nephropathy increased the risk of amputation threefold in all racial groups (Young et al 2003). Creatinine clearance, peripheral neuropathy and peripheral vascular disease have all been found to be independently associated with the formation of foot lesions. Griffiths et al (1990), however, found renal function by itself had no bearing on the severity of the lesions or the capacity to heal among kidney patients who mostly were not encumbered by hemodialysis, peritoneal dialysis or a history of renal transplantation; in such patients attempts to revascularize and preserve legs legs may be justified.Diabetic patients may be expected to develop more advanced renal disease and concurrently more advanced arteriosclerotic vascular disease in proportion to the duration of their diabetes and the elevations in their blood glucose levels. Those whose renal impairment has advanced to require hemodialysis or peritoneal dialysis may be expected to be burdened with generalized ASCVD, anemia and neuropathy. Their dialysis procedures expose them further to swings in fluid loads promoting congestive heart failure on one extreme and dehydration and hypotension on the other. When faint and hypotensive, they are commonly placed in a reverse Trendelenburg position significantly diminishing/stopping blood flow to their feet. Significant tissue necrosis may result. Again, in the transplant patient, the usage of steroids and other anti-rejection medications may potentially interfere with the recognition by immune cells of necrotic tissues and thus delay the healing process and/or the ability to resist infection.
Patients with ESRD have additional metabolic problems. As the creatinine clearance drops below 30ml/min, the ability to excrete the phosphate ion decreases. Hyperphosphatemia drives the concentration of ionized calcium down and secondary hyperparathyroidism results. In addition, hyperphosphatemia decreases the conversion of 25-hydroxycholecalciferol to the more active vitamin D metabolite 1,25-dihydroxycholecalciferol. Thus, ESRD may result in osteitis fibrosa cystica associated with hyperparathyroidism and osteomalacia associated with the hyperphosphatemia, together called renal osteodystrophy. The normalization or elevation in ionized calcium levels in the face of hyperphosphatemia promotes the deposition of ectopic calcifications and the "calciphylaxis" syndrome. The latter is a clinical diagnosis. Characteristic ischemic/necrotic skin lesions may be seen, typically appearing as dark bluish purple lesions and/or completely black leathery lesions. Skin biopsy, creating another lesion to heal, may be helpful in showing arterial calcification and occlusion in the absence of vasculitis. The best treatment of calciphylaxis is prevention: a low phosphate diet combined with agents like aluminum hydroxide gel to increase fecal phosphate losses. Dihydroxy-vitamin D may be required to cure the osteomalacia and lower bony alkaline phosphatase. Parathyroidectomies are indicated especially if tertiary hyperparathyroidism and hypercalcemia develop.
Those with foot ischemia may present with a spectrum of disease... asymptomatic ischemia, mild symptoms (numbness or cold feet), claudication, rest pain without tissue loss, focal tissue necrosis, larger areas of dry gangrrene, isolated plantar or toe ulcers, varying degrees of necrotizing cellulitis, and osteomyelitis of small or larger bones. Unfortunately, the greater the need of the patient, the more advanced the ischemia and the more advanced the tissue defects or infection, the less likely surgical revascularization and or minor amputation procedures will benefit the patient. Thus, Korn et al (2000) found their vascular reconstruction procedures in dialysis patients were associated with limb salvage in only 39% of limbs with extensive tissue loss at 1 year compared with 78% and 100% of limbs with limited and no tissue loss, respectively. Similar factors, of course, are operative among patients with and without ESRD. Abou-Zamzam et al(2007) reported among 224 patients with CLI that primary major AMPs were done in 97 cases (43%) and revascularization in 127 cases (57%). Nonwhite race/ethnicity, DM, ESRD, major tissue loss, dependent living situation, and nonambulatory status were all significant predictors of AMP versus leg revascularization. Duration of pre-operative time and type of insurance were not significant factors. Fifty-four percent of all primary major AMPs were performed due to extensive gangrene or infection present at initial vascular evaluation which precluded limb salvage. Jaar et al, found all cause mortality and the risk of amputation were higher in bypassed patients than in those with anatomy allowed angioplasty; in their series an uninsured status and/or reliance on Medicaid were also significant risk factors for amputation.
Prediction of mortality risk for ESRD patients undergoing surgery is difficult. When creatinine clearance was estimated as [140 - age (years)] x weight (kg)/72 x serum creatinine (mg/dl), multiplied by 0.85 for women, Maithel et al (2006) found it to be (independent of dialysis status) an independent predictor of mortality after lower extremity arterial reconstruction, while serum creatinine alone was not. There was no significant difference in serum creatinine values between survivors and non-survivors at 1, 2 or 3 years and creatinine >2 mg/dl did not predict long-term adverse outcomes. The authors, hence, recommended that determination of creatinine clearance should replace serum creatinine in the preoperative risk evaluations of patients undergoing major vascular surgical procedures. Other predictors of mortality included a history of stroke and congestive heart failure.
Survival of ESRD patients after vascular reconstruction, however, is poor. In the experience of Korn et al, overall patient survival was but 47% at 2 years and peritoneal dialysis especially was predictive of poor survival (4 of 5 patients dying within 3 months of intervention). Costs were significant:$44,308 per year of limb salvage. Quality of life was not considered. Koch et al (2007) concluded that bypass surgery in ESRD patients with foot ulcers as treatment of CLI is not the appropriate surgical approach, since this procedure did not cause a better survival than in patients who could not undergo revascularization surgery because of their poorer overall vascular condition.
Albers et al (2007) updated their meta-analysis of infrainguinal arterial reconstruction in ESRD patients with critical limb ischemia. Of 28 articles included, 18 reported amputation despite a patent graft in 84 (10%) out of 844 limbs, and 25 described a perioperative mortality of 88 (8.8%) out of 996 patients. The 5-year pooled estimate (SE) was 50.4% (15.4%) for primary patency, 50.8% (19.0%) for secondary patency, 66.6% (11.2%) for limb salvage, and 23.0% (11.7%) for patient survival. No publication bias was detected. They concluded that limb salvage can be achieved in most end-stage renal disease patients who undergo bypass surgery for critical ischemia, but, again, survival is poor. To avoid early amputation despite a patent graft, bypass grafting should not be offered to patients with a great amount of tissue loss or extensive infection. Korn et al add peritoneal dialysis as a indication for primary amputation.