Intradialytic Cramps Research Articles

Assessment of Volume Status Using Body Composition Monitor for Blood Pressure Control in Patients Undergoing Maintenance Hemodialysis: A Randomized Controlled Trial

Introduction: Optimal fluid balance and blood pressure control have been shown to improve outcomes in hemodialysis population. We investigated the effectiveness of body composition monitor (BCM) to target dry weight in maintenance hemodialysis (MHD) patients for blood pressure (BP) control and intradialytic adverse events. Methods: A total of 61 consenting adults under MHD were randomly allocated into either BCM group or Clinical Method group. Target dry weight was set every 4-weekly based on BCM report or clinical assessment; dry weight was adjusted with 200-500 ml/session reduction or increment of ultrafiltration in addition to interdialytic weight gain. Outcomes were analyzed in terms of BP control, anti-hypertensive medicine score, and intradialytic adverse events. Results: During 12 weeks of study period, systolic blood pressure (p<0.001), diastolic blood pressure (p=0.01) and mean arterial pressure (p<0.001) significantly decreased from baseline in BCM group but there were no significant changes in Clinical Method group. Lower blood pressure was achieved in BCM group as compared to Clinical Method group. There was a significant decrease from baseline in anti-hypertensive medicine score in the BCM group (p<0.001) but not in the clinical method group (p=0.34). There were significantly fewer events of cramps in the BCM group as compared to the Clinical Method group (p=0.04). Conclusion: BCM guided volume management in MHD patients was more effective than volume management based on clinical judgment only in controlling blood pressure and decreasing anti-hypertensive medicine burden and intradialytic cramps.

The effect of local cold application on intradialytic cramp: A quasi-experimental study.

An intradialytic cramp, which frequently occurs in hemodialysis patients, is a disturbing condition. This study was conducted to evaluate the effect of local cold applications on the severity and duration of intradialytic cramps in patients with chronic kidney disease. This quasi-experimental study sample comprised of 74 patients who were aged >18 years, conscious, and reported experiencing intradialytic cramps in a dialysis center. In this study, the application group had the local cold treatment as well as the treatment recommended by the physician whereas the control group was only given the treatment recommended by the physician. The cramp severity was assessed using a visual analog scale as soon as the cramp started (T1) and 10 min after the onset of the cramp (T2). The cramp duration was determined by a chronometer. The Independent Sample T-test, One-Way ANOVA test, Paired Samples T-test and the Two-Way ANOVA test were used to analyze the data. In the study, the duration of the cramp (sd) was 9.49 (0.86) minutes in the application group and 7.51 (0.69) minutes in the control group (t = 1791, p = 0.078). It was determined that the pain severity scores of the application and control group patients were significantly decreased at the T2 time point compared to T1 (p = 0.001), and the effect of the group and evaluation time points on the cramp severity score was not statistically different (p = 0.548). In this study, the mean duration of the intradialytic cramp was below 10 min for both groups. The local cold application had no effect on cramp severity or duration.

The efficacy and safety of low dialysate sodium levels for patients with maintenance haemodialysis: A systematic review and meta-analysis.

Fluid overload and hypertension frequently results in cardiovascular disease, which is one of the leading causes of death in dialysis patients. It is plausible that low dialysate [Na+] may decrease total body sodium content, thereby reducing fluid overload and hypertension, and ultimately reducing cardiovascular disease morbidity and mortality. This meta-analysis was designed to evaluate the efficacy and safety of using a low (<138mM) dialysate [Na+] for maintenance haemodialysis (HD) patients. We searched the Cochrane Library, PubMed, EMBASE, Web of Science up to August 22, 2019. Randomised controlled trials (RCTs), both parallel and cross-over, of low (<138mM) versus neutral (138-140mM) or high (>140mM) dialysate [Na+] for maintenance HD patients were included. Mean difference (MD), risk ratio (RR) and 95% confidence interval (CI) values were estimated to compare the outcomes. Two reviewers extracted data and assessed trial quality independently. All statistical analyses were performed using the standard statistical procedures of RevMan 5.2. 12 Randomised controlled trials with 390 patients were included in this meta-analysis. Of these studies, three studies were parallel group, and the remaining nine were crossover. Compared to neutral or high dialysate [Na+], low dialysate [Na+] reduced dialysis mean arterial pressure (MAP) with a pooled MD of -3.38mmHg (95% CI -4.57 to -2.19; P<0.00001), reduced interdialytic weight gain with a pooled MD of -0.35kg (95% CI -0.51 to -0.18; P<0.0001), reduced predialysis serum [Na+] with a pooled MD of -2.62mM (95% CI -3.59 to -1.66; P<0.00001). In contrast, low dialysate [Na+] increased intradialytic hypotension events with a pooled RR of 1.54 (95% CI 1.16 to 2.05; P=0.003), increased the incidence of intradialytic cramps with a pooled RR of 1.77 (95% CI 1.15 to 2.73; P=0.01). However, no difference was found between lower and higher dialysate [Na+] in systolic blood pressure and diastolic blood pressure. Though our pooled result indicated that low dialysate [Na+] reduced MAP, interdialytic weight gain and predialysis serum [Na+] significantly, it also indicated that low dialysate [Na+] could increase the incidence of intradialytic hypotension and intradialytic cramps events. Considering the contradiction in efficacy and safety of low dialysate [Na+] in our analysis, future larger and up-to-date definitive studies are needed to evaluate the medium to long-term effects of low sodium levels in dialysis fluid, and better inform clinical practice.

Low dialysate sodium levels for chronic haemodialysis.

Cardiovascular (CV) disease is the leading cause of death in dialysis patients, and strongly associated with fluid overload and hypertension. It is plausible that low dialysate [Na+] may decrease total body sodium content, thereby reducing fluid overload and hypertension, and ultimately reducing CV morbidity and mortality. This review evaluated harms and benefits of using a low (< 138 mM) dialysate [Na+] for maintenance haemodialysis (HD) patients. We searched the Cochrane Kidney and Transplant Register of Studies up to 7 August 2018 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. Randomised controlled trials (RCTs), both parallel and cross-over, of low (< 138 mM) versus neutral (138 to 140 mM) or high (> 140 mM) dialysate [Na+] for maintenance HD patients were included. Two investigators independently screened studies for inclusion and extracted data. Statistical analyses were performed using random effects models, and results expressed as risk ratios (RR) for dichotomous outcomes, and mean differences (MD) or standardised MD (SMD) for continuous outcomes, with 95% confidence intervals (CI). Confidence in the evidence was assessed using GRADE. We included 12 studies randomising 310 patients, with data available for 266 patients after dropout. All but one study evaluated a fixed concentration of low dialysate [Na+], and one profiled dialysate [Na+]. Three studies were parallel group, and the remaining nine cross-over. Of the latter, only two used a washout between intervention and control periods. Most studies were short-term with a median (interquartile range) follow-up of 3 (3, 8.5) weeks. Two were of a single HD session, and two of a single week's HD. Half of the studies were conducted prior to 2000, and five reported use of obsolete HD practices. Risks of bias in the included studies were often high or unclear, lowering confidence in the results.Compared to neutral or high dialysate [Na+], low dialysate [Na+] had the following effects on "efficacy" endpoints: reduced interdialytic weight gain (10 studies: MD -0.35 kg, 95% CI -0.18 to -0.51; high certainty evidence); probably reduced predialysis mean arterial blood pressure (BP) (4 studies: MD -3.58 mmHg, 95% CI -5.46 to -1.69; moderate certainty evidence); probably reduced postdialysis mean arterial BP (MAP) (4 studies: MD -3.26 mmHg, 95% CI -1.70 to -4.82; moderate certainty evidence); probably reduced predialysis serum [Na+] (7 studies: MD -1.69 mM, 95% CI -2.36 to -1.02; moderate certainty evidence); may have reduced antihypertensive medication (2 studies: SMD -0.67 SD, 95% CI -1.07 to -0.28; low certainty evidence). Compared to neutral or high dialysate [Na+], low dialysate [Na+] had the following effects on "safety" endpoints: probably increased intradialytic hypotension events (9 studies: RR 1.56, 95% 1.17 to 2.07; moderate certainty evidence); probably increased intradialytic cramps (6 studies: RR 1.77, 95% 1.15 to 2.73; moderate certainty evidence).Compared to neutral or high dialysate [Na+], low dialysate [Na+] may make little or no difference to: intradialytic BP (2 studies: MD for systolic BP -3.99 mmHg, 95% CI -17.96 to 9.99; diastolic BP 1.33 mmHg, 95% CI -6.29 to 8.95; low certainty evidence); interdialytic BP (2 studies:, MD for systolic BP 0.17 mmHg, 95% CI -5.42 to 5.08; diastolic BP -2.00 mmHg, 95% CI -4.84 to 0.84; low certainty evidence); dietary salt intake (2 studies: MD -0.21g/d, 95% CI -0.48 to 0.06; low certainty evidence).Due to very low quality of evidence, it is uncertain whether low dialysate [Na+] changed extracellular fluid status, venous tone, arterial vascular resistance, left ventricular mass or volumes, thirst or fatigue. Studies did not examine cardiovascular or all-cause mortality, cardiovascular events, or hospitalisation. It is likely that low dialysate [Na+] reduces intradialytic weight gain and BP, which are effects directionally associated with improved outcomes. However, the intervention probably also increases intradialytic hypotension and reduces serum [Na+], effects that are associated with increased mortality risk. The effect of the intervention on overall patient health and well-being is unknown. Further evidence is needed in the form of longer-term studies in contemporary settings, evaluating end-organ effects in small-scale mechanistic studies using optimal methods, and clinical outcomes in large-scale multicentre RCTs.

Low dialysate potassium concentration is associated with prolonged recovery time.

Modifiable hemodialysis treatment parameters may impact patient reported outcomes, including recovery time. Answers to the recovery question may predict the impact of treatment parameters on clinical outcomes and health related quality of life. However, the reliability of answers to the recovery question after consecutive and nonconsecutive dialysis treatments in diverse populations has not been established. To assess the reliability of this instrument and to determine if recovery time was associated with modifiable dialysis parameters, we conducted a quality assurance project in which we asked, "How long did it take you to recover from your last dialysis session?" after consecutive and nonconsecutive treatments. We asked patients the recovery question ≤ seven times. We computed polychoric correlations to assess within patient correlations. We used random intercept ordinal logistic regression models to test for associations of recovery time with patient variables. We obtained answers to the recovery question in association with 1572 treatments in 364 patients. Recovery time was <2 hours in 52.1%; 2 to 7 hours in 20.9%; and >7 hours in 27.0% of treatments. Polychoric correlations demonstrated highly reliable responses within individual patients between consecutive and nonconsecutive treatments. Prolonged recovery was associated with a dialysate potassium of 1 vs. 2 mEq/L (odds ratio [OR] 2.25 {95% confidence interval [CI] 1.43-3.55}) and 1 vs. 3 mEq/L (OR 1.88 [95% CI 1.06-3.33]); vintage >6 months (OR 2.43 [95% CI 1.42-4.16]), body mass index >35 kg/m2 (OR 1.94 [95% CI 1.18-3.20]), post-dialysis systolic blood pressure (SBP) <115 mmHg (OR 1.57 [95% CI 1.04-2.37]) and intradialytic cramps (OR 1.76 [95% CI 1.09-2.86]). There were no associations with gender, race, age, ESRD etiology, intradialytic SBP <90 mmHg, serum sodium or potassium, dialysate sodium, bicarbonate or temperature, blood flow rate, or ultrafiltration rate. Responses to the recovery question were reliable and low dialysate potassium was associated with prolonged recovery.

Dry weight assessment by combined ultrasound and bioimpedance monitoring in low cardiovascular risk hemodialysis patients: a randomized controlled trial.

Fluid overload is associated with adverse outcomes in hemodialysis (HD) patients. The precise assessment of hydration status in HD patients remains a major challenge for nephrologists. Our study aimed to explore whether combining two bedside methods, lung ultrasonography (LUS) and bioimpedance, may provide complementary information to guide treatment in specific HD patients. In total, 250 HD patients from two dialysis units were included in this randomized clinical trial. Patients were randomized 1:1 to have a dry weight assessment based on clinical (control) or LUS with bioimpedance in case of clinical hypovolemia (active)-guided protocol. The primary outcome was to assess the difference between the two groups on a composite of all-cause mortality and first cardiovascular event (CVE)-including death, stroke, and myocardial infarction. During a mean follow-up period was 21.3±5.6months, there were 54 (21.6%) composite events in the entire population. There was a nonsignificant 9% increase in the risk of this outcome in the active arm (HR=1.09, 95% CI 0.64-1.86, p=0.75). Similarly, there were no differences between the two groups when analyzing separately the all-cause mortality and CVE outcomes. However, patients in the active arm had a 19% lower relative risk of pre-dialytic dyspnea (rate ratio-0.81, 95% CI 0.68-0.96), but a 26% higher relative risk of intradialytic cramps (rate ratio-1.26, 95% CI 1.16-1.37). This study shows that a LUS-bioimpedance-guided dry weight adjustment protocol, as compared to clinical evaluation, does not reduce all-cause mortality and/or CVE in HD patients. A fluid management protocol based on bioimpedance with LUS on indication might be a better strategy.

In-center Nocturnal Hemodialysis

Some patients are not optimally treated by conventional in-center hemodialysis (HD) and are unable to perform home HD. We examined the effect of in-center thrice-weekly nocturnal HD (INHD) on patient outcomes. Patients who were not optimally treated on conventional HD were offered INHD. Thirty-nine patients' laboratory data and medication use were analyzed for the 12 mo before and after conversion to INHD until September 1, 2007. Quality of life on conventional HD and INHD was compared. After conversion to INHD, median values for phosphorus decreased from 5.9 to 3.7 mg/dl (P < 0.01), alkaline phosphatase level increased from 84 to 161 U/L (P < 0.01), and percentage reduction in urea increased from 74 to 89% (P < 0.01). The mean number of antihypertensive drugs prescribed declined from 2.0 to 1.5 (P < 0.05) during the course of INHD, and the mean daily dosage of phosphate binders declined from 6.2 to 4.9 at study end (P < 0.05). There was a significant reduction in erythropoietin-stimulating agent use of 1992 U/wk (P < 0.01). There was no significant change in median hemoglobin, iron saturation, corrected calcium, or parathyroid hormone levels. Overall, quality of life, sleep, intradialytic cramps, appetite, and energy level all improved significantly on INHD. INHD offers an effective form of HD for long-term dialysis patients who are unable to perform home HD.

Peripheral Arterial Disease Is Not Associated with an Increased Prevalence of Intradialytic Cramps in Patients on Maintenance Hemodialysis

Background/Aims: Peripheral arterial disease (PAD) has been suggested as a contributing factor to the development of intradialytic muscle cramps in patients on maintenance hemodialysis. Methods: To test this hypothesis, 122 patients from two dialysis centers were studied. The presence of PAD was determined by measurement of the ankle-brachial index (ABI) in the lower extremities of patients pre- and postdialysis. The experience of intradialytic cramps was assessed using patient history and review of medical records. Results: PAD defined as a predialysis ABI ≤0.90 had an overall prevalence of 16.4% among patients studied. The prevalence of PAD was age-dependent, reaching 37.5% in patients 80–89 years old. Intradialytic muscle cramps were common, with 52.1% of patients reporting cramps within the previous two months, but there was no relationship between cramps during dialysis and PAD (p > 0.05). Conclusions: PAD was common in hemodialysis patients, but there was no association between the presence of PAD and the prevalence of intradialytic muscle cramps.