The associations of hemodialysis access type and access satisfaction with health-related quality of life.

OBJECTIVE: In addition to age and comorbidities, health-related quality of life (HRQOL) is known to predict mortality in hemodialysis (HD) patients. Understanding the association of vascular access type with HRQOL can help surgeons to provide patient-centered dialysis access recommendations. We sought to understand the impact of HD access type on HRQOL. METHODS: We conducted a cross-sectional prospective study of community-dwelling prevalent HD patients in Pittsburgh, Pennsylvania. We assessed patient satisfaction with their access using the Vascular Access Questionnaire (VAQ) and HRQOL with the Short Form Health Survey. We compared access satisfaction and HRQOL across access types. We used logistic regression modeling to evaluate the association of access type with satisfaction and multivariate analysis of variance to evaluate the association of both of these variables on HRQOL. RESULTS: We surveyed 77 patients. The mean age was 61.8 ± 15.9 years. Arteriovenous fistula (AVF) was used by 62.3%, tunneled dialysis catheter (TDC) by 23.4%, and arteriovenous graft (AVG) by 14.3%. There was a significant difference in satisfaction by access type with lowest median VAQ score (indicating highest satisfaction) in patients with AVF followed by TDC and AVG (4.5 vs 6.5 vs 7.0; P = .013). Defining a VAQ score of <7 to denote satisfaction, AVF patients were more likely to be satisfied with their access, compared with TDC or AVG (77% vs 56% vs 55%; P = NS). Multivariate regression analysis yielded a model that predicted 46% of the variance of VAQ score; important predictors of dissatisfaction included <1 year on dialysis (ß = 3.36; P < .001), increasing number of access-related hospital admissions in the last year (ß = 1.69; P < .001), and AVG (ß = 1.72; P = .04) or TDC (ß = 1.67; P = .02) access. Mean physical and mental QOL scores (the composite scores of Short Form Health Survey) were not different by access type (P = .49; P = .41). In an additive multivariate analysis of variance with the two composite QOL scores as dependent variables, 25.8% of the generalized variance in HRQOL (effect size) was accounted for by access satisfaction with only an additional 3% accounted for by access type. CONCLUSIONS: HD patients experience greatest satisfaction with fistula, and access satisfaction is significantly associated with better HRQOL. Controlling for access satisfaction, there is no significant independent association of access type on HRQOL. Future research should investigate the relationship between access satisfaction, adherence to dialysis regimens, mortality, and the consequent implications for patient-centered care.

Predictors of cross-clamp-induced intraoperative monitoring changes during carotid endarterectomy using both electroencephalography and somatosensory evoked potentials.

OBJECTIVE: The efficacy of selective shunting during carotid endarterectomy (CEA) using intraoperative monitoring (IOM) for detection of cerebral ischemia is well established. There is mounting evidence that monitoring of both electroencephalography (EEG) and somatosensory evoked potentials (SSEPs) increases the sensitivity of cerebral ischemia detection. Predictors of cerebral ischemia requiring selective shunt placement using IOM of both EEG and SSEPs have not been previously identified. METHODS: Consecutive patients who underwent CEA between January 1, 2000, and December 31, 2010, were retrospectively analyzed. Primary end points were IOM changes at any time during the operation or IOM changes with carotid cross-clamping. Risk factors assessed included demographics; baseline comorbidities; severity of ipsilateral and contralateral disease; symptomatic status; and use of statin, antiplatelet, and beta-blocker medications. Univariate and multivariate logistic regression was used for analysis. RESULTS: During the 11-year study period, a total of 758 patients underwent 804 CEAs (mean age, 70.6 ± 9.5 years; 59.8% male; 39.2% symptomatic) using IOM of both SSEPs and EEG for selective shunting guidance. Postoperative stroke rate was 1.37%; 27.1% of patients had significant SSEP or EEG changes, and 49.1% of these were clamp induced (within 5 minutes of cross-clamping). Of these patients, 83.2% received a shunt (11.4% overall). The most common reason that a shunt was not placed after cross-clamp-induced changes was that the changes resolved with further blood pressure elevation (8 of 17 patients). Clamp-induced IOM changes were predictive of postoperative stroke (odds ratio [OR], 5.5; P = .005). Risk factors for clamp-induced IOM changes were contralateral carotid occlusion (OR, 2.5; P = .01), symptomatic stenosis (OR, 1.8; P = .006), and diabetes (OR, 1.6; P = .03), whereas there was a trend toward increased risk with female sex (OR, 1.5; P = .08). Risk factors for any IOM change (clamp and nonclamp induced) were symptomatic carotid stenosis (OR, 1.8; P < .001), use of beta blockers (OR, 1.5; P = .03), and female sex (OR, 1.5; P = .02). CONCLUSIONS: Whereas some patients can be expected to experience IOM changes by monitoring of SSEPs and EEG, a much smaller percentage will receive a shunt. Contralateral carotid occlusion, symptomatic stenosis, diabetes, and female sex increase the risk of clamp-induced IOM changes and should be anticipated to need a shunt. Patients receiving beta blockers are likely to experience IOM changes during the operation that are not associated with clamping.

Somatosensory Evoked Potentials and Electroencephalography during Carotid Endarterectomy Predict Late Stroke but not Death.

BACKGROND: Late stroke and death rates are anticipated to be higher in patients undergoing carotid endarterectomy (CEA) compared with healthy counterparts. However, little is known regarding predictors other than the baseline comorbidities. We have recently shown that dual intraoperative somatosensory evoked potentials (SSEPs) and electroencephalography (EEG) monitoring improves the ability to predict perioperative strokes. We seek to determine if dual intraoperative monitoring (IOM) can further predict long-term strokes and death. METHODS: Consecutive patients who underwent CEA under dual SSEP and EEG IOM between January 1, 2000 and December 31, 2010 were analyzed. Patients were divided in 2 groups, those with and those without IOM changes. IOM changes were classified as either occurring during carotid cross-clamp placement or at any time during the operation. End points were time to stroke and death. Log-rank tests and Cox regression analysis were used to identify predictors of postoperative stroke and death. RESULTS: A total of 853 CEAs (mean age 70.6 ± 9.5 years, 58.7% male, 38.9% symptomatic) were performed during the study period with a mean clinical follow-up of 48 ± 38 months. One hundred seven patients (13.6%) had significant SSEP or EEG changes at the time of clamping, while considerably more patients (217, 25.4%) had SSEP and/or EEG changes recorded at any point during the procedure, including clamping. Baseline characteristics including rates of bilateral disease, statin use, and antiplatelet use were similar between groups. Female gender, symptomatic disease, and significant contralateral carotid stenosis were more frequent in the group with IOM changes. The overall stroke-free survival rate at 5 years was significantly higher in patients without IOM changes (94.7% vs. 88.2%, P < 0.05) and at 10 years (86.1% vs. 78.0%, P < 0.05). Despite differences in stroke-free survival, overall survival at 10 years was not different between groups (44.0% in patients with IOM changes vs. 42.8% in patients without, P = 0.7). Renal insufficiency (hazards ratio [HR] 2.13, P = 0.03), diabetes (HR 1.84, P = 005), and age > 80 at the time of operation (HR 3.24, P = 0.001) were significant predictors of late stroke, while statins were significantly protective (HR 0.55, P = 0.05). Controlling for these factors, IOM changes (HR 2.5, P = 0.004) were a strong predictor of long-term risk of stroke after CEA. CONCLUSION: Intraoperative SSEP and/or EEG changes are predictive of late stroke but not death following CEA indicating a need for further elucidation and management of the underlying risk factors driving the elevated stroke risk in this subset of CEA patients.