Comparison of intradialytic blood pressure variability between conventional thrice‐weekly hemodialysis and short daily hemodialysis

Intradialytic blood pressure (BP) variability may be associated with increased mortality. We examined the effect of short daily hemodialysis (SDHD) on intradialytic BP variability relative to conventional thrice‐weekly HD (CHD). This is a retrospective cohort study. Subjects were those converted from CHD to SDHD (n=12). All intradialytic BPs were collected on the last month of CHD, and on month 6 of SDHD. Absolute predialysis BP level and intradialytic BP variability were defined as the intercept and average residual terms, respectively, from a mixed‐effects linear regression model of time on BP. Dialysis modality was a predictor variable (CHD vs. SDHD). Outcome variables were intradialytic BP variability and hypotension (BP<90/55 mmHg at any time during HD). In addition to a predictor and outcomes, the demographics, estimated dry weight, and ultrafiltration ratio were examined. The median (range) age of the patients was 48 (34–77); all had hypertension, and 4 (33%) had diabetes. By a mixed effects linear regression model, the intradialytic systolic BP variability was 13.2 (quartile range 9.5–14.0) mmHg and 10.0 (8.3–10.9) mmHg for CHD and SDHD, respectively (P<0.006). Intradialytic diastolic BP variability was also significantly reduced (7.7 [6.4–9.2] vs. 6.1 [5.5–6.6] mmHg, P=0.005). Relative to CHD, less hypotension was observed during treatment on SDHD: the odds ratio (95% confidence interval) was 0.36 (0.16–0.81; P=0.008). In this retrospective study, SDHD was associated with less intradialytic BP variability and with fewer episodes of hypotension during treatments. Further studies are necessary to generalize these findings.     

Unphysiology Is the Major Factor Influencing Cardiovascular Instability during Hemodialysis

Background: Hemodialysis is often complicated by cardiovascular instability (CVI). We studied factors contributing to this problem during 720 hemodialyses (HDs) in 20 patients; 480 dialyses were 6/week and 240 were 3/week. Methods: Dependent variables were increase in pulse rate (PR) and maximal (MAX) and overall (OV) fall of systolic blood pressure (BP). Independent variables were dialyses/week (DIAL), ultrafiltration (Uf), % of body weight (BW), pre‐post BUN (ΔBUN), time on dialysis (T), speed of dialysis (K/V in mL min^–1 kg^–1 BW), target‐postdialysis BW (Ta‐Po BW), Kt/V, ΔPO4, Δbicarbonate, Δpotassium, ΔBUN, an ‘unphysiology index’ summing up changes in electrolytes, and BUN and BW during dialysis (UPI). The relations were analyzed by backward multiple regression analysis. Results: PR increased 0.5 ± 11/min; MAX BP fall was 23 ± 17 mmHg; OV BP fall was 12 ± 19 mmHg. In multiple stepwise backward regression analysis, independents in order of importance: PR = 38 – DIAL × 4 + T × 0.1 + Uf × 1.8 +ΔPO4 × 1.8 – UPI× 0.2 – K/V × 2, r = 0.30, p < 0.0001; MAX BP = UPI × 0.4 – ΔBUN × 0.3 + ΔPO4 × 2.6 + 11, r = 0.34, p < 0.0001; OV BP = UPI × 0.4 – ΔBUN × 0.3 +ΔPO4 × 2.7 + 1, r = 0.33, p < 0.0001. Conclusion: To prevent BP fall and tachycardia during hemodialysis, the most important factor to decrease is unphysiology, i.e., the oscillations in electrolytes, fluid spaces, and osmolality that occur during dialysis. The best way to do this is to dialyze patients daily. An unexpected finding worthy of further investigation was the large detrimental influence of ΔPO4 on CVI.     

Hemodialysis‐induced regional left ventricular systolic dysfunction

Introduction Hemodialysis (HD) patients are under observably elevated cardiovascular mortality. Cardiac dysfunction is closely related to death caused by cardiovascular diseases (CVD). In the general population, repetitive myocardial ischemia induced left ventricular (LV) dysfunction may progress to irreversible loss of contraction step by step, and finally lead to cardiac death. In HD patients, to remove water and solute accumulated from 48 or 72 hours of interdialysis period in a 4‐hour HD session will induce myocardial ischemia. In this study, we evaluated the prevalence and potential risk factors associated with HD‐induced LV systolic dysfunction and provide some evidences for clinical strategies. Methods We recruited 31 standard HD patients for this study from Fudan University Zhongshan hospital. Echocardiography was performed predialysis, at peak stress during HD (15 minutes prior to the end of dialysis), and 30 minutes after HD. Auto functional imaging (AFI) was used to assess the incidence and persistence of HD‐induced regional wall motion abnormalities (RWMAs). Blood samples were drawn to measure biochemical variables. Findings Among totally 527 segments of 31 patients, 93.54% (29/31) patients and 51.40% (276/527) segments were diagnosed as RWMAs. Higher cTnT (0.060 ± 0.030 vs. 0.048 ± 0.015 ng/mL, P = 0.023), phosphate (2.07 ± 0.50 vs. 1.49 ± 0.96 mmol/L, P = 0.001), UFR (11.00 ± 3.89 vs. 8.30 ± 2.66 mL/Kg/h, P = 0.039) and lower albumin (37.83 ± 4.48 vs. 38.38 ± 2.53 g/L, P = 0.050) were found in patients with severe RWMAs (RWMAs in more than 50% segments). After univariate and multivariate analysis, interdialytic weight gain (IDWG) was found as independent risk factor of severe RWMAs (OR = 1.047, 95%CI 1.155–4.732, P = 0.038). Discussion LV systolic dysfunction induced by HD is prevalent in conventional HD patients and should be paid attention to. Patients would benefit from better weight control during interdialytic period to reduce ultrafiltration rate.     

The Clinical Impact of Increasing the Hemodialysis Dose

Good evidence suggests that improvements in dialysis efficiency reduce morbidity and mortality of hemodialysis (HD) patients. Dialysis efficiency has also been related to better control of arterial blood pressure (BP), anemia, and serum phosphorus levels, and to improvement in patients' nutritional status. Over a 2‐year period, the present self‐controlled study of 34 HD patients (23 men, 11 women; age, 52.6 ± 14.5 years; HD duration, 55.9 ± 61.2 months) looked at the effect on clinical and laboratory parameters of increasing the delivered dialysis dose under a strict dry‐weight policy. Dialysis dose was increased without increasing dialysis time and frequency. A statistically significant increase was seen in delivered HD dose: the urea reduction ratio (URR) increased to 60% ± 10% from 52% ± 8%, and then to 71% ± 7% (p < 0.001); Kt/V_urea increased to 1.22 ± 0.28 from 0.93 ± 0.19, and then to 1.55 ± 0.29 (p < 0.001). A statistically significant increase in hemoglobin concentration also occurred—to 10.8 ± 1.9 g/dL from 10.4 ± 1.7 g/dL, and then to 11.0 ± 1.3 g/dL (p < 0.05 as compared to baseline)—with no significant difference in weekly erythropoietin dose. Statistically significant decreases occurred in the systolic and diastolic blood pressures during the first year; they then remained unchanged. Systolic blood pressure decreased to 131 ± 23 mmHg from 147 ± 24 mmHg (p < 0.001); diastolic blood pressure decreased to 65 ± 11 mmHg from 73 ± 12 mmHg (p < 0.001). Serum albumin increased insignificantly to 4.4 ± 0.4 g/dL from 4.3 ± 0.4 g/dL, and then significantly to 4.6 ± 0.3 g/dL (p = 0.002 as compared to both previous values). Normalized protein catabolic rate increased significantly to 1.16 ± 0.15 g/kg/day from 0.93 ± 0.16 g/kg/ day (p < 0.001), and then to 1.20 ± 0.17 g/kg/day (p < 0.001 as compared to baseline). We conclude that the increases achieved in average Kt/V_urea per hemodialysis session by increasing dialyzer membrane area, and blood and dialysate flows, without increasing dialysis time above 4 hours, in patients hemodialyzed thrice weekly, coupled with strict dry‐weight policy, resulted in improvements in hypertension, nutritional status, and anemia.     

A study of the extracorporeal rate of blood flow and blood pressure during hemodialysis

Hemodynamic instability is a common problem during hemodialysis (HD). The effect of blood flow rate (BFR) on blood pressure (BP) during HD has not been previously evaluated. Subjects receiving HD for the treatment of renal failure were enrolled (n=34). For each patient, during the last hour of 2 consecutive HD sessions the BFR was set at 200 mL/min for 30 min and at 400 mL/min for 30 min, during which period the fluid removal rate was kept constant. The order of the BFR alterations was randomized. The study procedure was repeated during the next HD session but with reversal of the order of the altered BFR. During each 30-min period, BP was recorded at baseline and subsequently every 10 min. During the BFR of 400 mL/min, subjects had a higher systolic BP by an average of 4.1 mmHg compared with the BFR of 200 mL/min (95% confidence interval [CI] 0.22-7.98; p=0.038). Similarly, during the BFR of 400 mL/min, subjects had a higher diastolic BP by an average of 3.04 mmHg compared with the BFR of 200 mL/min (95% CI 0.55-5.53; p=0.017). Likewise, during the BFR of 400 mL/min, subjects had a higher mean arterial pressure by an average of 3.44 mmHg (95% CI 0.77-6.11; p=0.012). The findings suggest that during HD, BPs are maintained higher at higher BFRs as compared with lower BFRs.     

Effects of frequent hemodialysis on blood pressure: Results from the randomized frequent hemodialysis network trials

Hypertension is a common complication of chronic kidney disease and persists among most patients with end‐stage renal disease despite the provision of conventional thrice weekly hemodialysis (HD). We analyzed the effects of frequent HD on blood pressure in the randomized controlled Frequent Hemodialysis Network trials. The daily trial randomized 245 patients to 12 months of 6× (“frequent”) vs. 3× (“conventional”) weekly in‐center hemodialysis; the nocturnal trial randomized 87 patients to 12 months of 6× weekly nocturnal HD vs. 3× weekly predominantly home‐based hemodialysis. In the daily trial, compared with 3× weekly HD, 2 months of frequent HD lowered predialysis systolic blood pressure by ?7.7 mmHg [95% confidence interval (CI): ?11.9 to ?3.5] and diastolic blood pressure by ?3.9 mmHg [95% CI: ?6.5 to ?1.3]. In the nocturnal trial, compared with 3× weekly HD, 2 months of frequent HD lowered systolic blood pressure by ?7.3 mmHg [95% CI: ?14.2 to ?0.3] and diastolic blood pressure by ?4.2 mmHg [95% CI: ?8.3 to ?0.1]. In both trials, blood pressure treatment effects were sustained until month 12. Frequent HD resulted in significantly fewer antihypertensive medications (daily: ?0.36 medications [95% CI: ?0.65 to ?0.08]; nocturnal: ?0.44 mediations [95% CI: ?0.89 to ?0.03]). In the daily trial, the relative risk per dialysis session for intradialytic hypotension was lower with 6×/week HD but given the higher number of sessions per week, there was a higher relative risk for intradialytic hypotensive requiring saline administration. In summary, frequent HD reduces blood pressure and the number of prescribed antihypertensive medications.     

Echocardiographic Evidence of Altered Cardiac Status in Predialysis Diabetics and Those on Dialysis

Cardiovascular complications affect diabetic subjects early and the more susceptible ones are those on hemodialysis. Objective: This study was designed to observe prevalent cardiac involvement in both pre‐ and already on dialysis diabetics. Method: Sixty diabetics, 30 predialysis (predialysis diabetics, group 1), and 30 on maintenance hemodialysis (MHD, group 2) were randomly selected and their different clinical, biochemical, and echocardiographic parameters were compared. Result: Both groups of patients were matched for age, sex, and body mass index (BMI). Features like systolic and diastolic blood pressure were lower in predialysis diabetics group than in MHD group [138 ± 19 vs. 152 ± 32, p < 0.02 and 74 ± 10 vs. 87 ± 10 mmHg (p < 0.001)]; hemoglobin higher [10.3 ± 2.1 vs. 7.5 ± 1.5 g/dL (p < 0.001)]; serum creatinine was lower [3.49 ± 1.8 vs. 9.5 ± 2.5 mg/dL (p < 0.001)] (due to recruitment criteria); left ventricular muscle mass index (LVMI) also lower [137 ± 96 vs. 211 ± 77 g/m² (p < 0.001)]; left ventricular end diastolic volume index (LVEDVI) less [58 ± 21 vs. 85 ± 25 mL/m² (p < 0.001) and fractional shortening (FS, %) higher [33 ± 4.3 vs. 28 ± 5.8 (p < 0.006)]. Only 11% of Pre subjects had LV hypertrophy (LVMI >131 g/m² in male and in female LVMI >110 g/m²) whereas it was 51% in MHD (p < 0.001). Systolic dysfunction (FS = <25%) was 4% in Pre subjects and 24% in MHD (p < 0.03) group. Correlation study showed systolic and diastolic blood pressure; both had positive correlation with LVMI (r = 0.38, p < 0.008 and r = 0.32, p < 0.02) and LVEDVI (r = 0.36, p < 0.01 and r = 0.35, p < 0.01) and also similarly positive with serum creatinine (r = 0.35, p < 0.02 and r = 0.5, p < 0.001). Conclusion: It may be concluded that cardiac parameters are grossly altered in majority of diabetics on dialysis and higher serum creatinine and uncontrolled blood pressure may be responsible for this.     

Assessment of subjective and hemodynamic tolerance of different high‐ and low‐flux dialysis membranes in patients undergoing chronic intermittent hemodialysis: A randomized controlled trial

Clinical experience and experimental data suggest that intradialytic hemodynamic profiles could be influenced by the characteristics of the dialysis membranes. Even within the worldwide used polysulfone family, intolerance to specific membranes was occasionally evoked. The aim of this study was to compare hemodynamically some of the commonly used polysulfone dialyzers in Switzerland. We performed an open‐label, randomized, cross‐over trial, including 25 hemodialysis patients. Four polysulfone dialyzers, A (Revaclear high‐flux, Gambro, Stockholm, Sweden), B (Helixone high‐flux, Fresenius), C (Xevonta high‐flux, BBraun, Melsungen, Germany), and D (Helixone low‐flux, Fresenius, Bad Homburg vor der Höhe, Germany), were compared. The hemodynamic profile was assessed and patients were asked to provide tolerance feedback. The mean score (±SD) subjectively assigned to dialysis quality on a 1–10 scale was A 8.4 ± 1.3, B 8.6 ± 1.3, C 8.5 ± 1.6, D 8.5 ± 1.5. Kt/V was A 1.58 ± 0.30, B 1.67 ± 0.33, C 1.62 ± 0.32, D 1.45 ± 0.31. The low‐ compared with the high‐flux membranes, correlated to higher systolic (128.1 ± 13.1 vs. 125.6 ± 12.1 mmHg, P < 0.01) and diastolic (76.8 ± 8.7 vs. 75.3 ± 9.0 mmHg; P < 0.05) pressures, higher peripheral resistance (1.44 ± 0.19 vs. 1.40 ± 0.18 s × mmHg/mL; P < 0.05) and lower cardiac output (3.76 ± 0.62 vs. 3.82 ± 0.59 L/min; P < 0.05). Hypotension events (decrease in systolic blood pressure by >20 mmHg) were 70 with A, 87 with B, 73 with C, and 75 with D (P < 0.01 B vs. A, 0.05 B vs. C and 0.07 B vs. D). The low‐flux membrane correlated to higher blood pressure levels compared with the high‐flux ones. The Helixone high‐flux membrane ensured the best efficiency. Unfortunately, the very same dialyzer correlated to a higher incidence of hypotensive episodes.     

Stimulated sweating as a therapy to reduce interdialytic weight gain and improve potassium balance in chronic hemodialysis patients: A pilot study

Controlling the extracellular volume in hemodialysis patients is a difficult task. The aim of this study was to evaluate the capacity of different methods of stimulated sweating to reduce mean interdialytic weight gain (IWG), to improve blood pressure regulation, and potassium/urea balance. Two center, crossover pilot study. In Lausanne, hemodialysis patients took four hot‐water baths a week, 30 minutes each, on nondialysis days during 1 month. In Sfax, patients visited the local Hammam Center four times a week. Hemodynamic parameters were recorded, and weekly laboratory analysis was performed. Results were compared with a preceding 1‐month control period. In Lausanne, five patients (all men, median age 55 years) participated. Bathing temperature was (mean ± standard deviation) 41.2 ± 3°C and sweating‐induced weight loss 600 ± 500 g. Mean IWG (control vs. intervention period) decreased from 2.3 ± 0.9 to 1.8 ± 1 kg (P = 0.004), Systolic blood pressure from 139 ± 21 to 136 ± 22 mmHg (P = 0.4), and diastolic blood pressure form 79 ± 12 to 75 ± 13 mmHg (P = 0.08); antihypertensive therapy could be reduced from 2.8 ± 0.4 to 1.9 ± 0.5 antihypertensive drugs per patient (P = 0.01). In Sfax (n = 9, median age 46 years), weight loss per Hammam session was 420 ± 100 g. No differences were found in IWG or BP, but predialysis serum potassium level decreased from 5.9 ± 0.8 to 5.5 ± 0.9 mmol/L (P = 0.04) and urea from 26.9 ± 6 to 23.1 ± 6 mmol/L (P = 0.02). Hot‐water baths appear to be a safe way to reduce IWG in selected hemodialysis patients. Hammam visits reduce serum potassium and urea levels, but not IWG. More data in larger patient groups are necessary before definite conclusion can be drawn.     

Does hemodiafiltration reduce vascular stiffness measured by aortic pulse wave velocity compared with high‐flux hemodialysis?

Hemodialfiltration (HDF) has been reported to reduce the frequency of intradialytic hypotension compared with hemodialysis (HD). We wished to determine whether HDF resulted in improvement of arterial stiffness compared with HD. We reviewed peripheral blood pressure and pulse wave velocity measurements in a cross‐sectional analysis of stable HDF and HD outpatients. One hundred forty‐one HDF patients were matched to 148 HD patients in terms of age, sex, prevalence of diabetes, peripheral blood pressure, and body mass. Pulse wave velocity was not different between the HD and HDF cohorts (median 9.1 [8.0–10.7] m/s vs. 9.7 [8.5–11.6] m/s). Similarly, there were no differences in central aortic pressure (149.2 ± 30.9 mmHg vs. 151.9 ± 35.2 mmHg), or aortic (39 [25.1–51.2]% vs. 38.6 [25.8–51.4]%) and brachial (3.8 [?24.3 to 26.9]% vs. 3 [?22.4 to 27.1]%) augmentation indices, respectively. Pulse wave velocity did not differ between adult patients treated by HD and HDF, and similarly, there were no differences in central aortic pressure, aortic or brachial augmentation indices, and cardiac diastolic perfusion. Our study suggests that HDF does not appear to offer any benefit over HD in terms of vascular stiffness.     

The influence of blood volume-controlled ultrafiltration on hemodynamic stability and quality of life

Dialysis hypotension occurs frequently and is associated with increased morbidity, mortality, and may influence quality of life. We investigated the influence of blood volume (BV)-controlled ultrafiltration on hemodynamic stability and quality of life in a prospective multiple crossover study. Nineteen patients were consecutively treated with standard hemodialysis (HD), BV-controlled ultrafiltration, and again with standard ultrafiltration during 3-week phases, during which different hemodynamic parameters, ultrafiltrate quantities, dry weight, and quality of life were measured. Blood volume-controlled ultrafiltration resulted in increased hemodynamic stability: systolic blood pressure was significantly higher after treatment with BV-controlled HD compared with both standard treatments (p=0.018 and 0.043, respectively). Also, systolic blood pressure reduction, as a measure of blood pressure stability, was significantly smaller during the BV-controlled phase (-3.9 mmHg) compared with both standard phases (-13.7 and -11.0 mmHg): p=0.003 and 0.035, respectively. No difference was found in the occurrence of large decreases of blood pressure (>30 mmHg), decreases below 90 mmHg systolic pressure, or subjective complaints during treatment or after treatment between both treatment modalities. During the course of the study, the dry weight decreased significantly from mean 73.3 to mean 70.9 kg, and the amount of ultrafiltrate was significantly larger using BV-controlled HD compared with standard treatment (mean 2407 vs. mean 2266 mL; p=0.035). Quality of life, measured by visual analog scales (VAS), showed discrete but no consistent differences between study phases. We conclude that BV-controlled HD increases hemodynamic stability and ultrafiltrate amount compared with a standard treatment. No consistent change in quality of life is found between both treatment modalities.     

Comparison of serum albumin,C‐reactive protein and carotid atherosclerosis as predictors of 10‐year mortality in hemodialysis patients

Serum albumin, C‐reactive protein (CRP), and the intima‐medial thickness of the common carotid artery (CA‐IMT) are associated with clinical outcomes in hemodialysis (HD) patients. However, it remains unclear which parameters are more reliable as predictors of long‐term mortality. We measured serum albumin, CRP, and CA‐IMT in 206 HD patients younger than 80 years old, and followed them for the next 10 years. One hundred sixty‐eight patients (age: 57 ± 11 years, time on HD: 11 ± 7 years) were enrolled in the analyses. We divided all patients into three tertiles according to their albumin levels, and conducted multivariate analyses to examine the impact on 10‐year mortality. Seventy‐three (43.5%) patients had expired during the follow‐up. Serum albumin was significantly lower in the expired patients than in the surviving patients (3.8 ± 0.3 vs. 4.0 ± 0.3, P<0.01), while CRP (4.7 ± 5.0 vs. 2.8 ± 3.5 g/L, P=0.01) and CA‐IMT (0.70 ± 0.15 vs. 0.59 ± 0.11 mm, P<0.01) were significantly higher in the expired group. The multivariate analysis revealed that there was a significantly higher risk for total mortality in HD patients with serum albumin <3.8 g/dL (odds ratio 5.04 [95% CI: 1.30–19.60], P=0.02) when compared with those with albumin >4.1 g/dL. In contrast, CRP and CA‐IMT did not associate with total death. It follows from these findings that serum albumin is more superior as a mortality predictor compared with CRP and CA‐IMT in HD patients.     

Coronal mode ultrasound guided hemodialysis cannulation: A pilot randomized comparison with standard cannulation technique

Background: Infiltrations from cannulation result in significant morbidity including loss of hemodialysis (HD) vascular access (VA). Cannulation is dependent on personnel skill and VA characteristics. Surface marking of VA lacks real‐time information and traditional ultrasound (US) devices are large, expensive, requiring skilled operators. Sonic Window© (Analogic Ultrasound, Peabody, MA, USA) is a coronal mode ultrasound device (CMUD) approved for VA cannulation. Methods: Single center randomized, prospective pilot study comparing handheld US‐guided cannulation of new arteriovenous fistula (AVF) to standard cannulation practices. Patients with end stage renal disease (ESRD) on in‐center HD who had a new AVF cleared for cannulation and dialysis were enrolled. Patients with new AVF received either standard cannulation (control group) or image guidance using CMUD (study group) for 3 weeks. Ultrasound characteristics of VA, cannulation practices and complications end points were obtained. Results: An infiltration rate of 9.7% was noted during the study. Slightly lower odds ratio (OR) of infiltration was observed in the study group (OR 0.94, 95% CI: 0.26–3.41, P value = 0.93). Study group yielded longer time for assessment (101.8 ± 80.2 vs. 22.3 ± 22.5 seconds, P = < 0.001), increased cannulation time (41.1 ± 70.6 vs. 25.0 ± 27.9 seconds, P = 0.04), and increased patient satisfaction (94.6% vs. 82%, P = 0.04) compared to control group. Number of cannulation attempts, needle size, arterial or venous needle insertion, and tourniquet usage between groups were not statistically different. Conclusion: Handheld ultrasound is a safe and useful aid in cannulation of dialysis access.     

Safety analysis of intermittent hemodialysis in patients with continuous flow left ventricular assist devices

Dialysis centers adopt a cautious approach when it comes to performing intermittent hemodialysis (HD) on patients with continuous flow (CF) left ventricular assist devices (LVADs) because of the potential for volume flux‐related complications and absence of pulsatile blood pressure for monitoring. Many patients have to remain hospitalized because of the inability of the dialysis centers to accept them for outpatient dialysis. In this study, the effect of HD was observed in such patients. Between June 2009 and October 2012, 139 patients received LVADs, of which 10 patients (7%) required intermittent HD postoperatively. The mean age of the patients was 53 ± 14 years and 90% were men. A total of 281 dialysis sessions were administered amounting to 1025 hours of dialysis. The mean systolic blood pressure monitored with Doppler device was 97 ± 18 mmHg. Dialysis durations averaged 218 ± 18 minutes. Mean blood flow rate was 334 ± 38 cc/min, and 2.6 ± 1.1 L was ultrafiltrated during each session. Only 15 (5.3%) sessions were interrupted or terminated in six patients. The reasons for termination were symptomatic hypotension—6 (2.1%), asymptomatic hypotension—3 (1%), ventricular tachycardia—1 (0.36%), dialysis machine malfunction—2 (0.7%), low phosphorus—2 (0.7%), and abdominal cramps—1 (0.36%). Volume expansion was necessary on three occasions. Low‐flow device alarms were registered during two (0.71%) sessions. The results showed no serious adverse effects or deaths.     

Hemodynamic and Volume Changes during Hemodialysis

Background: Volume overload is a factor in the hypertension of hemodialysis (HD) patients. Fluid removal is therefore integral to the hemodialysis treatment. Fluid removal by hemodialysis ultrafiltration (UF) may cause intradialytic hypotension and leg cramps. Understanding blood pressure (BP) and volume changes during UF may eliminate intradialytic hypotension and cramps. Studies (S1, S2, and S3) were carried out to determine the amount and direction of changes in body fluid compartments following UF and to determine the relationships between BP, changes in blood volume (ΔBV), central blood volume (CBV), cardiac output (CO), peripheral vascular resistance (PVR) plus total body water (TBW), and intra‐ and extracellular fluid volumes (ICF, ECF) in both the whole body and body segments (arms, legs, trunk). Methods: Indicator dilution technology (Transonic) was used for CBV, CO, and PVR; hematocrit monitoring (Crit‐Line) was used for ΔBV segmental bioimpedance (Xitron) for TBW, ICF, and ECF. Results: S1 (n = 21) showed UF sufficient to cause ΔBV of ?7% and lead to minor changes (same direction) in CBV and CO, and with cessation of UF, vascular refilling was preferential to CBV. S2 (n = 20) showed that predialysis HD patients are ECF‐expanded (ECF/ICF ratio = 0.96, controls = 0.74 [P < 0.0001]) and BP correlates with ECF (r = 0.47, P = 0.35). UF to cause ΔBV of ?7% was associated with a decrease in ECF (P < 0.0001) and BP directly (r = 0.46, P = 0.04) plus ΔBV indirectly (r = ?0.5, P = 0.024) correlated with PVR, while CBV and CO were maintained. S3 (n = 11) showed that following UF, total‐body ECF changes were correlated with leg ECF (r = 0.94) and arm ECF (r = 0.72) but not trunk ECF. Absolute ECF reduction was greatest from the legs. Conclusions: Predialysis ECF influences BP and UF reduces ΔBV and ECF, but CBV and BP are conserved by increasing PVR. ECF reduction is mainly from the legs, hence may cause cramps. Intradialytic hypotension is caused by failure of PVR response.     

Alteplase vs. urokinase for occluded hemodialysis catheter: A randomized trial

Introduction Thrombosis of tunneled central venous catheters (CVC) in hemodialysis (HD) patients is common and it can lead to the elimination of vascular sites. To compare the efficacy of alteplase vs. urokinase in reestablishing adequate blood flow through completely occluded vascular catheters. Methods In this randomized study, patients with completely occluded tunneled HD catheters received 40 minutes intracatheter dwell with alteplase (1 mg/mL) or urokinase (5000 IU/mL). Primary endpoint was the proportion of patients with occluded catheters achieving post‐thrombolytic blood flow of ≥250 mL/min. Safety endpoints included the incidence of hemorrhagic and infectious complications. Findings Eligible adult patients (n = 100) were treated with alteplase (n = 44) or urokinase (n = 56). The two groups were similar in gender (male: 51.8% vs. 56.8%, P = 0.35), age (60 ± 12 vs. 59 ± 13 years, P = 0.71), time on dialysis (678 ± 203 vs. 548 ± 189 days, P = 0.77), diabetes and cardiovascular disease (55.6% vs. 70.4%, P = 0.08 and 17.8% vs. 22.7%, P = 0.38, respectively), jugular vein as main vascular access (54.8% vs. 62.5%, P = 0.57), and time of CVC (278 ± 63 vs. 218 ± 59 days, P = 0.67). Primary success with alteplase and urokinase occurred in 42/44 (95%) vs. 46/56 (82%), P = 0.06. Success was not achieved after the second dose of alteplase and urokinase in 1 and 7 cases, respectively (2% vs. 12%, P = 0.075). Serious adverse effects were not observed in both groups. There was no difference between the two groups in infectious complications (P = 0.94). Discussion Alteplase and urokinase are effective thrombolytic agents for restoring HD catheter patency. Our study has revealed a likely slight superiority of alteplase over urokinase for unblocking central lines, but which has enrolled too few patients to be able to detect a difference of this size.     

Acute complicating symptoms during hemodialysis sessions have well correlation with deranged blood pressure regulation

Objective: This observational study was undertaken to evaluate the frequency of acute complications occurring during dialysis sessions and their association with other clinical and biochemical parameters. Method: Forty‐six maintenance hemodialysis patients were selected and evaluated. Mean of the weekly evaluations of different parameters over a three‐month period is presented here. Result: Age of study subjects was 39 ± 13 years and body mass index (BMI) 21 ± 4 kg/m². Duration of hemodialysis was 41 ± 29 months. Most of the patients were hypertensive (98%), taking multiple anti‐hypertensive drugs. Mean of the blood pressures before and at the end of dialysis sessions over the three month period were: systolic blood pressure (SBP) 159 ± 18 vs. 163 ± 22 (p < 0.05) and diastolic blood pressure (DBP) 92 ± 13 vs. 87 ± 7 mmHg (p < 0.003). Frequency of acute complicating symptoms during dialysis sessions were: headache (75%), rise in blood pressure (73%), leg cramps (67%), vomiting (60%), palpitation (58%), sweating (52%), and hypotension (35%). Raised blood pressure showed a positive correlation with headache (r = 0.50, p < 0.01) and sweating (r = 0.53, p < 0.05). Vomiting and palpitation were more frequent at low post‐dialysis blood pressure (vomiting vs. post‐SBP‐r = ?0.41, p < 0.05 and palpitation vs. post‐DBP‐r = ?0.48, p < 0.05), and these patients were likely to get inadequate dialysis (hypotension vs. Kt/V‐r = ?0.63, p < 0.01). Pre and post dialysis weight variation was 53 ± 11 vs. 51 ± 11 kg (p < 0.001), average ultrafiltration during dialysis (UF)?2.39 (0.5–4) liter and single session Kt/V was 0.95 ± 0.38. The rising tendency of post‐dialysis blood pressure correlated positively with increasing UF (SBP vs. UF‐r = 0.36, p < 0.01 and DBP vs. UF‐r = 0.25, p < 0.05). Conclusion: From this study it may be concluded that acute complications during dialysis sessions have a significant correlation with deranged blood pressure regulation, and optimum control of blood pressure could provide better dialysis.     

Serum coenzyme Q10 levels are associated with coronary flow reserve in hemodialysis patients

Accelerated atherosclerosis is the major cause of mortality in patients on chronic hemodialysis (HD). The aim of this study was to evaluate the relation between coenzyme Q10 (CoQ10) levels and coronary flow reserve (CFR) in HD patients as an indicator of atherosclerosis. Seventy‐one chronic HD patients and 65 age‐ and sex‐matched healthy individuals were included in the study. Plasma CoQ10 levels were performed by high‐performance liquid chromatography measurements. CFR was assessed by transthoracic Doppler echocardiography. Serum CoQ10 levels (1.36 ± 0.43 vs. 2.53 ± 0.55, P < 0.001) and CFR values (1.73 ± 0.11 vs. 2.32 ± 0.28, P < 0.001) were significantly lower in HD patients compared with controls. There was a significant positive correlation between CFR and serum levels of CoQ10 (r = 0.669, P < 0.001). A linear regression analysis showed that serum levels of CoQ10 were still significantly and positively correlated with CFR (regression coefficient = 0.235, P < 0.001). Our data have demonstrated that HD patients exhibit decreased plasma CoQ10 levels and CFR values. The study also showed for the first time that serum CoQ10 levels independently predict CFR in HD patients.