Determinants of heart rate variability in chronic hemodialysis patients

To clarify determinants of heart rate variability in hemodialysis patients, we evaluated 187 patients receiving chronic hemodialysis. Ambulatory electrocardiogram was recorded for 24 hours from the beginning of hemodialysis. Standard deviation of the normal RR interval (SDNN) was used as a marker of heart rate variability. Multiple regression analysis was performed to select independent variables associated with SDNN from the following 14 variables: age, sex, body mass index before hemodialysis, presence of ischemic heart disease, diabetic nephropathy as primary renal disease, smoking, duration of hemodialysis, mean blood pressure before hemodialysis, left ventricular mass index and fraction shortening in echocardiography, use of beta blockers, use of angiotensin-converting enzyme inhibitors, hematocrit, and blood urea nitrogen. Older age (P < 0.0001), presence of diabetic nephropathy as primary renal disease (P < 0.0001), lower hematocrit (P = 0.0121), larger body mass index before hemodialysis (P = 0.0133), longer duration of hemodialysis (P = 0.0200), and smoking (P = 0.0350) were associated with reduced SDNN. In hemodialysis patients, SDNN as a marker of cardiac autonomic modulation was associated with hematocrit, body mass index, and duration of hemodialysis, in addition to previously reported variables.     

Bioimpedance analysis and intradialytic hypotension in intermittent hemodialysis

BACKGROUND: Intradialytic hypotension (IDH) is one of the most severe complications during hemodialysis. Its appearance is caused in part by rapid fluid removal with concomitant failure in blood pressure regulation but also by other dialytic-dependent and independent factors. PATIENTS AND METHODS: We investigated total (TBW), extracellular (ECW) and intracellular water (ICW) in chronic intermittent hemodialysis dialysis hypotension-prone (CRF-HP, n = 11) and nonhypotension-prone (CRF-NHP, n = 10) patients with end-stage renal disease before, every 30 minutes during, as well as after dialysis and within onset of intradialytic hypotension by multifrequent bioimpedance analysis (BIA). Additionally, intradialytic time course of BIA in patients with acute renal failure (ARF) and septic shock (n = 10) was observed. RESULTS: IDH occurred in 72.1% of CRF-HP and in 80% of ARF patients. In CRF-HP and CRF-NHP, ECW significantly decreased by -12.44 +/- 4.22% in CRF-HP and -9.0 +/- 6.2% in CRF-NHP comparing pre- and post-dialysis values (each p < 0.01). Conversely, ICW increased by +11.5 +/- 11.3% in CRF-HP and +18.4 +/- 25.2% in CRF-NHP (each p < 0.05). In patients with ARF no significant changes could be detected. Calculated ECW/ICW and ECW/TBW ratio significantly decreased in CRF patients with a higher rate in CRF-HP patients (p < 0.05). Neither ECW/ICW nor ECW/TBW ratio correlated with mean arterial pressure. The onset of intradialytic hypotension (n = 35) did not differ intraindividually compared to normotensive periods (n = 411). Fluid removal in CRF patients seems to be mainly from the extracellular space. The reduced decreases in ECW/ICW and ECW/TBW ratios in CRF-HP compared to CRF-NHP may indicate an insufficient refilling from intra- to extracellular compartment in CRF-HP. CONCLUSION: In conclusion, multifrequent BIA is not capable to predict hypotension in the individual patient during a particular dialysis session.     

Association of intradialytic hypotension and 5-year mortality in maintaining hemodialysis patients

Objective To assess the risk factors of intradialytic-hypotension (IDH) and the prognosis of IDH among maintenance hemodialysis (MHD) patients for the prevention and treatment of IDH. Methods 276 MHD patients were enrolled during Jan. 2009 to Mar. 2009. Intradialytic blood pressure was monitored during a 3-month period. IDH was defined as an event characterized by a sudden drop in systolic BP more than 20 mmHg or in mean artery pressure (MAP) more than 10 mmHg associated with clinical events and need for interventions. Dialysis-related information was collected. Kaplan-Meier method, log-rank test, logistic regression and Cox regression analyses were performed to examine the association between IDH and survival, using a follow-up through 31 May 2014. Results A total of 276 patients were recruited. The incidence rate of IDH was 40.9%. 163 patients with no-IDH (＜1/10 hypotensive events/3 months) served as controls. 113 patients with IDH (≥1/10 hypotensive events/3 months) were identified among all 276 patients. Multivariate logistic regression analysis showed that age, ultrafiltration rate, gender, serum NT-proBNP, serum albumin and aortic rool inside dimension (AoRD) were associated with IDH among MHD patients. During the 5-year follow-up, 74 patients died, with a mortality rate 5.2 per 100 person-year. Kaplan-Meier survival curve showed significant difference of overall and CV mortality rates between 2 groups. The multivariate Cox regression model indicated that IDH increased the risk of death (HR=1.572, 95%CI 1.077-2.293, P=0.019). So did the rise of LVMI (HR=1.010, 95%CI 1.009-1.085, P=0.020). Conclusion Elderly, female, high ultrafiltration rate, high level of serum NT-proBNP, hypoalbuminemia and shorter AoRD are independent risk factors for IDH among MHD patients. LVMI can predict the outcome of MHD patients. Intradialytic hypotension is an independent risk factor for long-term mortality in MHD patients.     

Heart rate variability predicts severe hypotension after spinal anesthesia

BACKGROUND: Hypotension due to vasodilatation after spinal anesthesia (SA) may be harmful. Heart rate variability, an indirect measure of autonomic control, may predict hypotension. METHODS: One hundred patients were studied. Retrospectively, heart rate variability was analyzed in 30 patients, classified depending on the lowest systolic blood pressure (SBP) after SA. Seventy patients were studied prospectively, assigned to one of two groups by their low to high frequency ratio (LF/HF) before SA. Sensitivity and specificity of LF/HF for prediction of decrease of SBP greater 20% of baseline were tested. RESULTS: Retrospective analysis showed differences of LF/HF depending on the degree of hypotension after SA. Prospective analysis demonstrated significant differences of SBP after SA depending on baseline LF/HF (mean +/- SD): low LF/HF (1.3 +/- 0.7) = > SBP: 91 +/- 8% of baseline versus high LF/HF (5.5 +/- 2.4) = > SBP: 66 +/- 10% of baseline (P < 0.05). Baseline LF/HF as well as high frequency and proportional decrease of SBP after SA correlated significantly, in contrast to baseline hemodynamic parameters heart rate and SBP. A receiver operator curve characteristic analysis showed a sensitivity and specificity of LF/HF > 2.5 of 85% to predict SBP decrease of greater than 20% of baseline after SA. CONCLUSIONS: Heart rate variability analysis before SA may predict hypotension after SA with high sensitivity and specificity. LF/HF may be a tool to detect patients at high risk of hypotension due to SA. This indicates that the predictive value of LF/HF is superior to established predictors.     

Heart rate variability, left ventricular functions, and cardiac autonomic neuropathy in patients undergoing chronic hemodialysis

OBJECTIVE: Autonomic neuropathy and impairment of left ventricular functions (LVF) have been frequently encountered in chronic renal failure (CRF). The aim of the present study was to evaluate the relationship of cardiac autonomic modulation impairments, as assessed by means of heart rate variability (HRV), with clinical characteristics, and left ventricular function in the patients with CRF undergoing hemodialysis (HD). METHODS: Twenty control subjects (Group I) and 22 comparable by age and gender patients with CRF undergoing hemodialysis (Group II) were enrolled in the study. After routine clinical and biochemical evaluations, electrocardiography, and 2 Dimensional, M Mode echocardiography were performed in all participants. Frequency domain HRV analysis was studied by using Kardiosis System. The powers (P1 and P2) and the central frequencies (F1 and F2) of low and of high frequency spectral bands were recorded. RESULTS: End systolic (ESV) and end diastolic volumes (EDV) were significantly higher in Group II (59.3 +/- 21.1mL vs. 34.0 +/- 14.3 mL and 131.5 +/- 37.3 mL vs. 96.9 +/- 18.9 mL, p < 0.01, p < 0.05, respectively) when compared to those of Group I. Ejection fraction (EF) and fractional shortening (FS) were significantly lower in Group II than in control subjects (52.3 +/- 2.4% vs. 63.7 +/- 10.1% and 0.29 +/- 0.01 vs. 0.34 +/- 0.07, p < 0.001, p < 0.05, respectively). P and P2 were decreased in Group II than in Group I (136.2 +/- 173.9 m s2 vs. 911.0 +/- 685.5 and 96.5 +/- 149.6 vs. 499.7 +/- 679.5, p < 0.001, p < 0.01, respectively). Significant correlations were found between high frequency spectral power and dialysis duration (DD), ESV, EDV, EF, FS (r = 0.52 p < 0.01, r = 0.68 p < 0.001, r = 0.65 p < 0.002, r = 0.66 p < 0.02, and r = 0.69 p < 0.01). CONCLUSION: As a result, the dependence of cardiac autonomic neuropathy on the disease duration and degree of left ventricular function impairment was shown in the patients undergoing chronic hemodialysis.     

Serum chromogranin A concentration and intradialytic hypotension in chronic haemodialysis patients

Aim The aim of this study was to investigate the influence of haemodialysis on plasma chromogranin A (CgA) concentration and to assess the relationship between CgA, blood pressure, occurrence of intradialytic hypotension episodes and residual renal function, respectively. Methods The study included 38 chronic haemodialysis patients (24 M, 14 F; mean age 56.2 ± 13.6 years). Plasma CgA and blood pressure were measured before and after a mid-week dialysis. Control group included 10 age- and sex-matched healthy subjects. Results Plasma CgA levels were on average 50-fold higher in HD patients than in the controls (699 ± 138 vs. 14 ± 6 U/L). In HD patients plasma CgA corrected for ultrafiltration rates significantly increased (to 836 ± 214 U/L, P < 0.001) at the end of dialysis procedure. In patients with (n = 8) and without frequent symptomatic intradialytic hypotension episodes predialysis values of CgA were similar (701 ± 169 vs. 698 ± 132 U/L) but post-dialysis were significantly lower in the former group (746 ± 312 vs. 860 ± 177 U/L; P = 0.03) despite a similar rate of ultrafiltration (2675 ± 1009 and 2583 ± 1311 ml, respectively). Accordingly, in patients with intradialytic hypotension an increase of plasma CgA during dialysis was also much lower than in patients without hypotension (45 ± 81 vs. 163 ± 144 U/L; P = 0.001). Conclusions CgA undergoes marked accumulation in renal failure. The increase of plasma CgA during dialysis is impaired in subjects with intradialytic hypotension episodes, which confirms the role of autonomic dysfunction in the pathogenesis of this complication.     

Intradialytic hypotension is associated with dialytic age in patients on chronic hemodialysis

Abstract

Objective: Intradialytic hypotension (IDH) is common in patients on chronic hemodialysis, but knowledge on determinants is still unclear. The present study aims at evaluating the association between IDH and dialytic age (DA) in patients on chronic hemodialysis. Methods: Between January 2012 and January 2013, 82 patients on chronic hemodialysis for at least 1?year were screened for inclusion in the present study. Of these, 14 were excluded because of advanced heart failure (n.9), history of alcohol/substance abuse (n.1), diagnosis of dementia (n.2), actual instability of clinical conditions requiring hospitalization (n.2). IDH was defined as a decrease in systolic blood pressure ≥20?mmHg or a decrease in mean arterial pressure (MAP) by 10?mmHg associated with clinical events and need for nursing interventions. The number of IDH episodes in 10 consecutive hemodialysis sessions was recorded for each patient. Linear and logistic regressions were adopted to assess the adjusted association between IDH and DA. Results: The mean DA was 92?±?81. Eleven patients (16%) experienced IDH. DA was associated with IDH (OR?=?1.01; 95% CI?=?1.01–1.02; p?=?0.048), after adjusting for potential confounders. DA was associated with the numbers of IDH events in the unadjusted model (B?=?0.02; 95% CI?=?0.01–0.03; p?=?0.042), after adjusting for age and sex (B?=?0.01; 95% CI?=?0.01–0.03; p?=?0.042) as well as in the multivariable model (B?=?0.02; 95% CI?=?0.01–0.05; p?=?0.045). Conclusion: DA is associated with an increased probability of IDH and with increased number of IHD events. Studies are needed to understand the underlying factors of such an association.     

Investigation of heart rate variability and heart rate turbulence in chronic hypotensive hemodialysis patients

International Urology and Nephrology - Sudden cardiac death is the leading cause of cardiac-related death in hemodialysis patients. Hypotensive episodes in pre-, intra-, and post-dialytic periods...     

Heart rate variability predicts severe hypotension after spinal anesthesia for elective cesarean delivery

BACKGROUND: Hypotension due to vasodilation during subarachnoid block (SAB) for elective cesarean delivery may be harmful. Heart rate variability (HRV), reflecting autonomic control, may identify patients at risk of hypotension. METHODS: Retrospectively, HRV was analyzed in 41 patients who were classified into one of three groups depending on the decrease in systolic blood pressure (SBP): mild (SBP > 100 mmHg), moderate (100 > SBP > 80 mmHg), or severe (SBP < 80 mmHg). Prospectively, HRV and hemodynamic data of 19 patients were studied. Relative low frequency (LF), relative high frequency (HF), and LF/HF ratio were analyzed. RESULTS: Retrospective analysis of HRV showed a significantly higher sympathetic and lower parasympathetic drive in the groups with moderate and severe compared with mild hypotension before SAB (median, 25th/75th percentiles): LF/HF: mild: 1.2 (0.9/1.8), moderate: 2.8 (1.8/4.6), P < 0.05 versus mild; severe: 2.7 (2.0/3.5), P < 0.05 versus mild. Results were confirmed by findings of LF and HF. Prospectively, patients were grouped according to LF/HF before SAB: low-LF/HF: 1.5 (1.1/2.0) versus high-LF/HF: 4.0 (2.8/4.7), P < 0.05; low-LF: 58 +/- 9% versus high-LF: 75 +/- 10%, P < 0.05; low-HF: 41 +/- 10% versus high-HF: 25 +/- 10%, P < 0.05. High-risk patients had a significantly lower SBP after SAB (76 +/- 21 vs. 111 +/- 12 mmHg; P < 0.05). CONCLUSIONS: Retrospectively analyzed HRV of patients scheduled to undergo elective cesarean delivery during SAB showed significant differences depending on the severity of hypotension after SAB. Preliminary findings were prospectively confirmed. High LF/HF before SAB predicted severe hypotension. Preoperative HRV analysis may detect patients at risk of hypotension after SAB.     

Heart rate variability during chronic hemodialysis and after renal transplantation: studies in patients without and with systemic amyloidosis.

The present study was undertaken to compare heart rate variability (HRV) values in patients on maintenance hemodialysis with no evidence of ischemic or hypertensive heart diseases to those of age- and gender-matched healthy individuals and those of patients after renal transplantation. To assess the effects of a common confounding factor, HRV values were also determined in patients with systemic amyloidosis, in chronic hemodialysis, and after successful renal transplantation. Spectral analyses of RR intervals from continuous electrocardiogram recordings were performed to quantify ultra low frequency, very low frequency, low frequency, and high frequency powers. HRV determinations were all significantly reduced in uremic patients undergoing hemodialysis compared with the healthy control subjects, especially in those with systemic amyloidosis. Renal transplantation normalized HRV in most patients; HRV, however, remained reduced in isolated amyloidosis patients with cardiac or adrenal involvement. HRV circadian day/night differences were preserved in hemodialysis patients and after renal transplantation in those without amyloidosis but not in those with amyloidosis. These data suggest that reduced HRV in chronic hemodialysis patients may precede other manifestations of cardiovascular disease. In uremic patients with amyloidosis, a more severe form of autonomic failure may occur. Successful transplantation corrects HRV abnormalities in most patients, suggesting that the autonomic dysfunction of uremia is caused by humoral factors reversed by the normalization of the renal function.     

维持性血液透析患者透析中运动锻炼的最佳证据总结

目的 总结维持性血液透析患者透析中运动锻炼的最佳证据,为指导血液透析患者透析治疗中运动锻炼提供参考。方法 按照证据金字塔模型,检索维持性血液透析患者透析中运动锻炼的相关文献,检索时限从建库至2021年7月31日。采用乔安娜布里格斯研究所循证卫生保健中心相对应的文献评价标准和证据分级系统进行文献质量评价与证据等级划分。结果 共纳入文献11篇,包括指南1篇、专家共识1篇、系统评价9篇,汇总血液透析中运动必要性、运动禁忌证、运动安全性、运动益处、运动时间、运动频率、运动强度、运动程序方式、运动指导监督、注意事项10个方面共38条最佳证据。结论 总结的维持性血液透析患者透析中运动证据全面、实用,血液透析护士可应用证据指导血液透析患者进行透析中运动锻炼。     

High ultrafiltration rate induced intradialytic hypotension is a predictor for cardiac remodeling: a 5-year cohort study

BackgroundIntradialytic-hypotension (IDH) is a common complication of hemodialysis. High ultrafiltration rate (UFR) might lead to IDH. However, the relationships between UFR, IDH, and cardiac remodeling among hemodialysis patients in the long-term have not been deeply explored.MethodsThis retrospective cohort study collected clinical and echocardiographic data. Patients were enrolled from 1 January 2014 to 31 March 2014 and were followed-up for 5-year. Those who suffered from more than four hypotensive events during three months (10% of dialysis treatments) were defined as the IDH group. Subgroup analysis was done according to the UFR of 10 ml/h/kg. Associations between UFR, IDH, and alterations of cardiac structure/function were analyzed.ResultsAmong 209 patients, 96 were identified with IDH (45.9%). The survival rate of IDH patients was lower than that of no-IDH patients (65.5% vs. 81.4%, p = .005). In IDH group, decreased ejection fraction (EF), larger left atrium diameter index (LADI), and left ventricular mass index (LVMI) (p < .05) were observed at the end of the follow-up. In multivariate logistic model, the interaction between UFR and IDH was notably associated with LVMI variation (OR = 1.37). After adjusting covariates, UFR was still an independent risk factor of LVMI variation (OR = 1.52) in IDH group. In subsequent analysis, we divided patients according to UFR 10 ml/h/kg. For IDH-prone patients, decreased EF, larger LADI, and LVMI (p < .05) were observed at the end of the study only in high-UFR group.ConclusionsUFR and IDH have interactions on cardiac remodeling. High ultrafiltration rate induced IDH is a predictor for cardiac remodeling in long-term follow-up.     

品管圈活动在降低血液透析相关性低血压发生率中的作用

目的探讨应用品管圈（quality control circle,QCC）方法降低血液透析相关性低血压发生率的效果。方法选择2011年10月在航空总医院血液透析中心发生透析相关性低血压患者21例为研究对象,成立品管圈活动小组、确立活动课题,进行现状调查、分析发生血液透析相关性低血压的原因、设定目标值、制订对策并实施,比较实施品管圈活动前后低血压的发生率。结果开展品管圈活动后血液透析相关性低血压发生率从15．00％下降到5．38％,活动前后比较,差异具有统计学意义（P〈0．05）。结论品管圈活动可降低血液透析相关性低血压发生率。     

A patient with an uncommon etiology of intradialytic hypotension

Hemodialysis is associated with various complications, the most common being intradialytic hypotension (IDH). In the majority of cases, IDH is easily corrected and does not represent a life-threatening condition. We present a patient in whom IDH was unresponsive to various corrective strategies. A new mitral valve regurgitant lesion was diagnosed that eventually led to the patient's demise. Unusual etiologies of IDH need to be considered, particularly in instances where routine therapeutic measures are ineffective.     

Symptomatic intradialytic hypotension and mortality: an opinionated review

The unchanging rate of symptomatic hypotension that attends maintenance hemodialysis and its link to sodium/volume overload are explored. Correlations between interdialytic weight gain, ultrafiltration rate, hypertension, and mortality are found to be strong. Suggestions/opinions for correcting this unfortunate clinical reality are offered.     

The relationship between survival rate and intradialytic blood pressure changes in maintenance hemodialysis patients

Objective: The objective of this study is to investigate the relationship between blood pressure changes and all-cause mortality, and between blood pressure changes and cardiovascular mortality, for maintenance hemodialysis (MHD) patients during dialysis.

Methods: Data regarding general condition, biochemical indices, and survival prognosis of MHD patients who were treated at the Shanghai Jiao Tong University School of Medicine-affiliated Renji Hospital from July 2007 to December 2012 were collected, in order to evaluate the relationship between patients’ blood pressure changes during hemodialysis and mortality.

Results: Among 364 patients, with an average age of 63.07?±?13.93?years, an average dialysis vintage of 76.00 (range, 42.25–134.00) months, and a follow-up time of 54.86?±?19.84?months, there were 85 cases (23.4%) of all-cause death and 46 cases (14.2%) of cardiovascular death. All-cause mortality and cardiovascular mortality were lowest (OR, 0.324 and 0.335; 95% CI, 0.152–0.692 and 0.123–0.911; p value, .004 and .032, respectively) in patients whose systolic blood pressure difference (ΔSBP) before and after dialysis was between 7.09 and 14.25?mmHg. Kaplan–Meier analysis indicated that both all-cause mortality and cardiovascular mortality were markedly increased for patients with ΔSBPless than ?0.25?mmHg (p value, .001 and .044, respectively). Cox regression analysis showed that ΔSBPKt/v and albumin were independent risk factors for all-cause mortality in MHD patients.

Conclusions: MHD patients whose blood pressure increased significantly after hemodialysis had a higher risk of dying; ΔSBP, hemoglobin concentration, Kt/v and albumin were independent risk factors for all-cause mortality in MHD patients.