Blood temperature monitoring-guided vascular access intervention improved dialysis adequacy

OBJECTIVES

The aim of this study was to investigate whether blood temperature monitoring-guided vascular access intervention could improve dialysis adequacy.

METHODS

We retrospectively evaluated all patients who received outpatient-based prevalent hemodialysis patients (n = 84) in our artificial kidney room between January 2019 and October 2019. Through blood temperature monitoring, access blood flow was calculated every month and Kt/V was calculated every 3 months. The reference point was set at the time of vascular intervention in the patients (n = 27) who underwent intervention or at the middle of the study period in patients (n = 57) who did not undergo intervention. The mean blood temperature monitoring-estimated access flow and Kt/V before and after the reference point were calculated and compared.

RESULTS

Among 84 patients, 30 (35.7%) showed access flow rates of <500 mL/min, calculated by blood temperature monitoring during the study period. Twenty-seven patients (32.1%) underwent vascular intervention, of whom 24 (28.6%) showed access flow rates of <500 mL/min, 2 (2.4%) showed weak bruit or thrill incapable of needling, and 1 (1.2%) presented acute occlusion. Six patients (7.1%) whose access flow rates were <500 mL/min refused to undergo intervention. All angiographies in the patients whose access flow rates were <500 mL/min who underwent intervention showed a significant stenosis. The mean change in blood temperature monitoring-estimated access flow and Kt/V before and after vascular intervention was 483.3 ± 490.6 and 0.19 ± 0.21, respectively, which showed significant differences (all p < 0.05). A weak positive correlation between the mean change in blood temperature monitoring-estimated access flow and Kt/V was shown in all study patients by Pearson's correlation analysis (r = 0.234, p = 0.033).

CONCLUSION

Access flow estimation by blood temperature monitoring might identify candidates who require vascular intervention. Blood temperature monitoring-guided vascular intervention significantly improved access flow and dialysis adequacy.

Dialysis-specific factors and incident atrial fibrillation in hemodialysis patients

Background

Atrial fibrillation (AF) is common in end-stage renal disease patients. Besides the traditional risk factors, we aimed to find dialysis-specific factors for developing incident AF.

Methods

From March 2017 to August 2018, we retrospectively reviewed all outpatient-based prevalent hemodialysis patients in our artificial kidney room, and they were followed up until August 2019. Dialysate calcium concentration (3 versus 2.5 mEq/L), time length (4 versus 3.5 h), frequency (thrice weekly versus twice weekly), dialyzer size (effective surface area of 1.4 m² versus 1.8 m²), membrane permeability (high flux versus low flux), ultrafiltration rate (mL/kg/hour), and blood flow rate (mL/min) were evaluated.

Results

Among a total of 84 patients, 15 (17.9%) had newly detected AF with a follow-up period of 21 (13.3–24) months. By performing multivariate Cox regression analysis, blood flow rate (mL/min) and ultrafiltration rate (mL/kg/h) were considered significant factors for developing incident AF (adjusted hazard ratio [HR], 0.977; p = 0.011 and adjusted HR, 1.176; p = 0.013, respectively), while dialysis bath, time length, and frequency, dialyzer size, and membrane type were not considered significant factors. Ultrafiltration cutoff rate of 8.6 mL/kg/h was the best predictive factor for incident AF (area under the curve-receiver operating characteristic [AUC-ROC], 0.746; p < 0.005), while blood flow rate was not considered a significant factor for incident AF in ROC analysis (AUC-ROC, 0.623; p = 0.126). Ultrafiltration rate was largely dependent on interdialytic weight gain (p < 0.005, linear-by-linear association).

Conclusion

Higher ultrafiltration rate was associated with incident AF in hemodialysis patients.

Nutritional Adequacy and Latent Tuberculosis Infection in End-Stage Renal Disease Patients

Background: Latent tuberculosis infection (LTBI) is prevalent in end-stage renal disease (ESRD) patients. The risk of tuberculosis activation is also high. The appropriate LTBI screening and treatment is required in this population. Meanwhile, whether hemodialysis adequacy is associated with LTBI in the ESRD population is unclear. In this study, we aimed to investigate the association between hemodialysis adequacy and LTBI in ESRD patients. Methods: In the present cross-sectional study, we reviewed all outpatient-based ESRD patients in our artificial kidney room. Interferon gamma release assay (IGRA) was used for the diagnosis of LTBI. Clinical variables including nutritional adequacy (i.e., normalized protein catabolic rate, nPCR) and dialysis adequacy (i.e., Kt/V) were compared between IGRA-positive and IGRA-negative patients. Results: A total of 90 patients were enrolled, of which 20 (22.2%) had positive IGRA results using the QuantiFERON-TB method. Old fibrotic changes and nPCR (g/kg/day) were significantly different between IGRA-positive and IGRA-negative patients (both p < 0.005), while serum albumin and Kt/V were comparable (p = 0.429 and p = 0.590, respectively). Normalized PCR remained to be significant in a multivariate logistic regression analysis (adjusted hazard ratio, 0.911 (0.861–0.963); p = 0.001). The cutoff nPCR value less than 0.87 g/kg/day had an adjusted hazard ratio of 7.74 (1.77–33.74) for predicting LTBI. Patients with nPCR value less than 0.87 g/kg/day were older and had lower serum hemoglobin, albumin, calcium concentration, and Kt/V levels than those with nPCR value greater than 0.87 g/kg/day. Conclusions: Nutritional adequacy, especially when assessing nPCR value, was associated with LTBI, while dialysis adequacy was not associated with LTBI.

A Case Series of Asymptomatic Hemodialysis Catheter-Related Right Atrial Thrombi That Are Incidentally Detected Prior to Kidney Transplantation

A hemodialysis (HD) catheter-related right atrial thrombus (RAT) is rarely encountered prior to kidney transplantation (KT) but necessitates a decision about whether to anticoagulate and/or delay the surgery. There is controversy surrounding the clinical implications of a RAT in this situation. It is sometimes considered fatal but other opinions consider it to be benign, especially when incidentally detected. We reviewed the clinical characteristics, management, and outcomes of a patient series with HD catheter-related RAT detected prior to KT and speculated on its clinical significance. Among 3677 cases of KT performed on 3607 patients between January 1997 and September 2015 in our single tertiary center, 11 cases of HD catheter-related RAT detected on transthoracic echocardiography (TTE) prior to KT were included for analysis. The average maximal diameter of the RAT was 23.2 ± 16.3 (SD in mm) and 9 (81.8%) of these 11 patients had no symptoms associated with the RAT. Four patients (36.3%) had their catheters replaced, 5 patients (45.5%) had their catheters removed, and the catheters were maintained in the remaining 2 patients (18.2%). Six patients (54.5%) were anticoagulated with either heparin or warfarin. However all 11 patients had a successful KT suggesting that a HD catheter-related RAT incidentally detected prior to this surgery may not be as serious as previously considered and should not be a reason for delaying the transplantation.

Use of fludrocortisone for intradialytic hypotension

Intradialytic hypotension during dialysis adversely affects a patient’s prognosis and increases mortality. We report a case in which intradialytic hypotension that persisted after the administration of midodrine was relieved after the use of fludrocortisone. Administration of 0.2 mg of fludrocortisone occurred 30 minutes before dialysis. We compared 45 sessions of dialysis without fludrocortisone administration and 45 sessions of dialysis with fludrocortisone administration in one patient. The number of times in which systolic blood pressure became lower than 80 mmHg and the number of early terminations of dialysis due to a decrease in systolic blood pressure were higher in the sessions without fludrocortisone administration than in the sessions with fludrocortisone administration (P < 0.05). Fludrocortisone may be helpful for the treatment of intradialytic hypotension that does not respond to midodrine administration.

Risk factors for new-onset diabetes mellitus after living donor kidney transplantation in Korea - a retrospective single center study

BACKGROUND

New-onset diabetes mellitus after transplantation (NODAT) is a serious complication following renal transplantation. The aim of this study was to identify the risk factors for the development of NODAT in Korean transplant patients.

METHODS

Recipients who underwent living donor kidney transplantation between January 2009 and April 2012 at Asan Medical Center were reviewed. Diagnosis of NODAT was defined according to the American Diabetes Association criteria.

RESULTS

A total of 418 patients were enrolled. NODAT was diagnosed in 85 (20.4 %) patients within 1 year. By multivariate analysis, old age (odds ratio [OR], 1.05; 95 % Confidence interval [CI]: 1.01-1.08), family history of diabetes mellitus (OR, 2.48; 95 % CI: 1.04-5.94), pre-transplant high serum glucose level (OR, 1.04; 95 % CI: 1.01-1.08), and obesity (OR, 3.46; 95 % CI: 1.55-7.73) were independent risk factors for NODAT.

CONCLUSION

Old age, family history of diabetes, pre-transplant high plasma glucose level, and obesity are independent factors associated with the development of diabetes after renal transplantation. In contrast, serum magnesium levels and the use of tacrolimus are not associated with the development of NODAT.

Underrated value of repeated right heart catheterization in pulmonary hypertension with heart failure-a case of persisted pulmonary arterial hypertension after treatment for biventricular failure

Pulmonary hypertension (PH) is a common complication of left heart disease and its presence in patients with heart failure predicts worse clinical outcomes. Specific agents targeting pulmonary arterial hypertension (PAH) have been developed over the last few years, but the efficacy of these agents in pulmonary hypertension due to left heart disease (PH-LHD) is uncertain. We report a case of idiopathic pulmonary arterial hypertension (IPAH) initially presented with biventricular failure, which was misdiagnosed as PH-LHD. A 31-year-old man who had a history of recurrent hemoptysis was referred to our center with biventricular failure. Right heart catheterization (RHC) showed elevated mean pulmonary arterial pressure (mPAP) and pulmonary capillary wedge pressure (PCWP). He was diagnosed as having PH-LHD, specifically combined post-capillary and precapillary PH (CpcPH). We treated him for 2 years with diuretics, a beta blocker, an angiotensin-converting enzyme (ACE) inhibitor, and sildenafil, which was added to treat CpcPH. A follow-up echocardiography showed that biventricular function had improved, but not PH. A second RHC revealed elevated mPAP and normal PCWP, which made us change the diagnosis to IPAH. In conclusion, it is important to perform repeated RHC in CpcPH patients after the improvement of left heart dysfunction to distinguish CpcPH from IPAH.