Significance of nutrition in hemodialysis patients with peripheral arterial disease evaluated by skin perfusion pressure

Background Peripheral artery disease (PAD) is a serious complication in hemodialysis (HD) patients. Low skin perfusion pressure (SPP) is a useful marker for detecting PAD. Malnutrition is an important cause of intractable complications. We examined the relationship between low SPP and various indicators of nutritional status. Methods A total of 120 patients on maintenance HD were enrolled for SPP measurement. SPP was measured at the soles of both feet during HD, and patients were divided into low SPP (L-SPP) and normal SPP (N-SPP) groups by 50 mmHg. The following values were determined by averaging four blood samples taken before SPP measurements every 3 months for one year: hemoglobin, total protein, albumin (Alb), total cholesterol, urea nitrogen, creatinine (Cr), potassium, calcium, phosphate, intact parathyroid hormone, iron (Fe), transferrin saturation (T-SAT), and C-reactive protein (CRP). We calculated the percent Cr production rate, dialysis index (Kt/V), normalized protein catabolic rate (nPCR), geriatric nutritional risk index (GNRI), and estimated salt intake using the required formulas. In addition, the age, body mass index, and presence of diabetes mellitus (DM) were compared between both groups along with all other measurements. Data were expressed as the mean ± standard deviation or median with interquartile range as appropriate. Differences in continuous variables between the two groups were analyzed by Student’s t-test or Wilcoxon’s rank-sum test, as appropriate. Multivariate logistic analysis and receiver operating curve (ROC) analysis were performed for significant variables. The results were expressed as odds ratios with respective 95% confidence intervals (CIs). Results The enrolled patients were 82 men and 38 women, with a mean age of 66.9 ± 13.3 years and HD duration of 4.76 (2.13–12.28) years (median interquartile range). Twenty patients belonged to the L-SPP group, suggesting PAD. Comparison between the L-SPP and N-SPP groups showed significant differences in age, Cr, Fe, T-SAT, CRP, nPCR, GNRI, DM, and estimated salt intake. When the GNRI, estimated salt intake, CRP, and DM were applied as independent variables for multiple logistic regression analysis, the GNRI (odds ratio: 0.857, 95% CI 0.781–0.941, p = 0.001), CRP (2.406, 1.051–3.980, p = 0.035), and DM (9.194, 2.497–33.853, p = 0.001) were found to be significant for L-SPP, and a cutoff level of 92.1 (sensitivity 80%, specificity 72%, AUC: 0.742, 95% CI 0.626–0.858, p = 0.001) in the GNRI obtained by ROC was consistent with the risk index in the elderly presented previously. Conclusions SPP measurement is an essential tool for detecting high-risk PAD in maintenance HD, which is affected by malnutrition, DM, and inflammation. The GNRI is important for the determination of malnutrition.

Association between Flow-Mediated Dilation and Skin Perfusion Pressure with Peripheral Artery Disease in Hemodialysis Patients

Flow-mediated dilation (FMD) is used to noninvasively assess the health of blood vessels and it has been shown to have a similar predictive ability for cardiovascular disease to traditional risk factors. Skin perfusion pressure (SPP) refers to the blood pressure required to restore capillary or microcirculatory flow after controlled occlusion and the return of flow. SPP has been shown to be an important measurement when making clinical decisions for patients with limb ischemia and to be a predictor of the likelihood of wound healing. Peripheral artery disease is common in hemodialysis (HD) patients. However, little is known about the association between FMD or SPP and peripheral artery disease. The aim of this study was to evaluate the association between FMD and SPP with brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI) in HD patients in Taiwan, an area with a high rate of ESRD. This study was conducted at a regional hospital in southern Taiwan. ABI and baPWV values were measured using an ABI automated device. FMD and SPP were measured using ultrasound and a microvasculature blood flow monitor, respectively. Eighty patients were enrolled in this study. Compared to the patients with an ABI ≥ 0.95, those with an ABI < 0.95 had lower SPP of the feet (dorsal and plantar portions, both p < 0.001). After multivariable adjustments, low triglycerides (p = 0.033) and high calcium–phosphate product (p = 0.018) were significantly associated with low FMD. Further, low ABI (p = 0.001) and low baPWV (p = 0.036) were significantly associated with low SPP of dorsal portions. Old age (p = 0.005), low high-density lipoprotein cholesterol (p = 0.016), and low ABI (p = 0.002) were significantly associated with low SPP of plantar portions. This study demonstrated an association between FMD and SPP with peripheral artery disease in HD patients. Patients with low ABI and baPWV had a high risk of low SPP of the feet. However, there was no significant correlation between FMD and ABI or baPWV.

The Degree of Blood Supply and Infection Control Needed to Treat Diabetic Chronic Limb-Threatening Ischemia with Forefoot Osteomyelitis

Background Diabetic foot ulcers combined with ischemia and infection can be difficult to treat. Few studies have quantified the level of blood supply and infection control required to treat such complex diabetic foot ulcers. We aimed to propose an index for ischemia and infection control in diabetic chronic limb-threatening ischemia (CLTI) with forefoot osteomyelitis. Methods We retrospectively evaluated 30 patients with diabetic CLTI combined with forefoot osteomyelitis who were treated surgically from January 2009 to December 2016. After 44 surgeries, we compared patient background (age, sex, hemodialysis), infection status (preoperative and 1- and 2-week postoperative C-reactive protein [CRP] levels), surgical bone margin (with or without osteomyelitis), vascular supply (skin perfusion pressure), ulcer size (wound grade 0–3 using the Society for Vascular Surgery Wound, Ischemia, and foot Infection classification), and time to wound healing between patients with healing ulcers and those with nonhealing ulcers. Results Preoperative CRP levels and the ratio of ulcers classified as wound grade 3 were significantly lower and skin perfusion pressure was significantly higher in the healing group than in the nonhealing group (P &lt; .05). No other significant differences were found between groups. Conclusions This study demonstrates that debridement should be performed first to control infection if the preoperative CRP level is greater than 40 mg/L. Skin perfusion pressure of 55 mm Hg is strongly associated with successful treatment. We believe that this research could improve the likelihood of salvaging limbs in patients with diabetes with CLTI.

Skin perfusion pressure for predicting access-related hand ischemia following arteriovenous fistula surgery based on the brachial artery

Background: Access-related hand ischemia (ARHI) is a major complication of arteriovenous fistula (AVF). This study aimed to assess the predictive efficacy of skin perfusion pressure (SPP) measurement for ARHI by examining the relationship between SPP and ARHI development and progression after AVF surgery. Methods: Twenty-five patients (16 men and 9 women) who underwent AVF surgery based on the brachial artery between January 2018 and December 2018 were included. The pre- and postoperative SPP values were measured on the day of surgery. ARHI occurrence and severity were measured within 3 days and at 6 months after surgery. Receiver operating characteristic curve analysis was used to evaluate the prediction model of ARHI, and the cutoff points for the calculated coefficients were determined. Results: There was a significant correlation between the occurrence of immediate ARHI and the SPP gradient ( p = 0.024). An SPP gradient value >50 mmHg had sensitivity and specificity values of 53.85% and 91.67%, respectively, in predicting the occurrence of immediate ARHI. A postoperative SPP <48 mmHg was significantly correlated with the occurrence of 6-month ARHI ( p = 0.005), with sensitivity and specificity values of 71.43% and 83.33%, respectively. Conclusion: The SPP gradient and postoperative SPP values may be effective clinical predictors of ARHI occurring immediately and 6 months after surgery, respectively, with high specificity. These findings could allow clinicians to diagnose and begin early interventions to help prevent ischemic tissue damage in hemodialysis patients following AVF surgery.

Maggot debridement therapy in critical limb ischaemia: a case study

Objective: In critical limb ischaemia (CLI), first-line therapy is revascularisation, but alternative treatment options are needed in certain cases. Maggot debridement therapy (MDT) is historically considered to be contraindicated in ischaemic ulcers. Wound care in patients with CLI is becoming increasingly diverse with the development of novel revascularisation strategies; therefore, CLI now needs to be reconsidered as an indication for MDT. Method: We retrospectively reviewed five legs with CLI (five male, one female) treated with MDT between January 2013 and December 2017. Changes in skin perfusion pressure (SPP) around the ulcer before and after MDT were evaluated. One or two cycles of MDT were performed (eight in total). We also evaluated the proportion of necrotic tissue in the ulcer and the presence of exposed necrotic bone. The proportion of necrotic tissue in the ulcer was classified as NT 1+ (<25%), NT 2+ (25–50%), NT 3+ (50–75%) or NT 4+ (>75%). Results: When the proportion of necrotic tissue was >50%, with no exposed necrotic bone in the wound, an increase in SPP was observed after five (62.5%) of eight cycles of MDT. And with a proportion of necrotic tissue of <25% and/or exposed necrotic bone in the wound, a decrease in SPP was observed after three (37.5%) of eight cycles. Wound healing was accelerated in the presence of increased SPP. Conclusion: Effective MDT with increased SPP requires an ulcerative state of necrotic tissue grade > NT 3+, with no exposed necrotic bone.

Changes in Skin Perfusion Pressure After Endovascular Treatment for Chronic Limb-Threatening Ischemia

Purpose To assess skin perfusion pressure (SPP) changes after endovascular treatment (EVT) of patients with chronic limb-threatening ischemia (CLTI) and to explore preoperative factors that affect SPP changes. Materials and Methods This prospective, multicenter study recruited 147 patients (mean age 74 years; 99 men) with ischemic wounds at 6 vascular centers in Japan between July 2017 and December 2018. Over half of the patients (92, 63%) were diabetic, and 76 (52%) required dialysis. Sixty-four patients (43%) had WIfI (wound, ischemia, foot infection) wound grades of 2 or 3; 59 (40%) had foot infections. SPP was measured before and 1, 2, 7, and 30 days after EVT to establish inline flow to the ischemic foot based on the angiosome concept when feasible. The anterior and posterior tibial arteries and the peroneal artery were revascularized in 66 (45%), 50 (34%), and 30 (21%) patients, respectively. Results Both the dorsal and plantar SPPs at 1 or 2 days post-EVT were significantly higher than those at baseline (p<0.001), and both SPPs increased further at 1 month compared with those at 1 (p=0.001) or 2 days (p=0.006) post-EVT. SPP increases occurred on the dorsal and plantar surfaces of the foot regardless of the vessel revascularized. The SPP increase at 1 month after EVT was significantly lower in patients with foot infections than that in those without foot infections (p=0.003). Age, sex, diabetes, dialysis, wound severity, and direct revascularization did not affect the pattern of SPP change. Conclusion The SPP increased continuously up to 1 month after EVT, though the increase was smaller in patients with wound infections. The SPP on the dorsal and plantar surfaces increased, regardless of the vessel revascularized, which could justify indirect revascularization when direct revascularization is technically challenging.