Israel Medical Association Journal

Background: Hemodialysis requires reliable, recurrent access to the circulatory system. Central venous tunneled dialysis catheters (TDC) are frequently used for patients receiving hemodialysis as a bridge to permanent vascular access or as a final option. TDC are prone to complications such as infection and dysfunction.

Objective: To assess the prevalence and predictors of TDC dysfunction in a cohort of chronic hemodialysis patients.

Methods: This single-center, retrospective study was based on data from an electronic database of chronic hemodialysis patients during 5 years of follow-up.

Results: A total of 625 TDC were inserted in 361 patients, of which 234 (37.4%) were replaced due to dysfunction. The main insertion site was the right internal jugular vein. Diabetes mellitus was an important predictor of TDC dysfunction and was significantly correlated with TDC extraction. Chronic anticoagulation and antiplatelet treatment did not affect the rate of TDC dysfunction or replacement.

Conclusions: TDC use for chronic dialysis patients is increasing and dysfunction is a major problem. In our study, we highlighted the high prevalence of TDC dysfunction and the need for further research to improve hemodialysis access as well as TDC patency and function.

Background: Reliable vascular access is a fundamental tool for providing effective hemodialysis. Vascular access dysfunction is associated with increased morbidity and mortality among hemodialysis patients. Current vascular access guidelines strongly recommend creating an arteriovenous fistula (AVF) as the first option; however, a substantial proportion of new AVFs may not be usable.

Objectives: To assess possible predictors of primary and secondary failure of vascular access.

Methods: This retrospective cohort study included all vascular access sites created at Meir Medical Center from 2006 through 2012. Vascular access site, primary and secondary failure rates, and relevant demographic and clinical data were recorded during 60 months of follow-up.

Results: A total of 612 vascular accesses were created and followed for a median of 32 ± 29.4 months. Of these, 490 (80%) were suitable for initiating hemodialysis. Vascular access site was the most important predictor of primary failure but did not predict secondary failure. Co-morbidities such as diabetes mellitus and congestive heart failure, as well as the use of antiplatelet agents did not predict primary or secondary failure. Preoperative vascular mapping using Doppler ultrasonography was performed in 36.4% of cases and was not associated with lower rates of primary or secondary failure.

Conclusions: Vascular access site is an important predictor of primary failure. We did not find a benefit of pre-operative vessel mapping or chronic antiplatelet therapy in terms of decreasing primary and secondary failure rates. Physicians should carefully consider the characteristics of the patient and blood vessels before creating vascular access in patients requiring chronic hemodialysis.

Background: Magnesium is an essential intracellular cation. Magnesium deficiency is common in the general population and its prevalence among patients with cirrhosis is even higher. Correlation between serum levels and total body content is poor because most magnesium is intracellular. Minimal hepatic encephalopathy is a subclinical phase of hepatic encephalopathy with no overt symptoms. Cognitive exams can reveal minor changes in coordination, attention, and visuomotor function, whereas language and verbal intelligence are usually relatively spared.

Objectives: To assess the correlation between intracellular and serum magnesium levels and minimal hepatic encephalopathy.

Methods: Outpatients with a diagnosis of compensated liver cirrhosis were enrolled in this randomized, double-blinded study. Patients were recruited for the study from November 2013 to January 2014, and were randomly assigned to a control (placebo) or an interventional (treated with magnesium oxide) group. Serum and intracellular magnesium levels were measured at enrollment and at the end of the study. Cognitive function was assessed by a specialized occupational therapist.

Results: Forty-two patients met the inclusion criteria, 29 of whom were included in this study. Among these, 83% had abnormal cognitive exam results compatible with minimal hepatic encephalopathy. While only 10% had hypomagnesemia, 33.3% had low levels of intracellular magnesium. Initial intracellular and serum magnesium levels positively correlated with cognitive performance.

Conclusions: Magnesium deficiency is common among patients with compensated liver cirrhosis. We found an association between magnesium deficiency and impairment in several cognitive function tests. This finding suggests involvement of magnesium in the pathophysiology of minimal hepatic encephalopathy.

Background: Upper respiratory tract infection (URTI) occurs frequently in the general population and is considered a benign self-limited disease. Dialysis patients constitute a high risk population whose morbidity and mortality rate as a result of URTI is unknown. 

Objectives: To assess the local incidence, morbidity and mortality of URTI in dialysis patients compared to the general population. 

Methods: In this retrospective cohort study we reviewed the charts of all chronic dialysis patients diagnosed with URTI at Meir Medical Center, Kfar Saba, Israel during the 2014–2015 winter season. 

Results: Among 185 dialysis patients, 40 were found to be eligible for the study. The average age was 66.1 ± 15.7 years, and the co-morbidity index was high. Influenza A was the most common pathogen found, followed by rhinovirus, respiratory syncytial virus and para-influenza. Of the 40 patients 21 (52.5%) developed complications: pneumonia in 20%, hospitalization in 47.5%, and respiratory failure requiring mechanical ventilation in 12.5%. Overall mortality was 10%. General population data during the same seasonal period showed a peak pneumonia incidence of 4.4% compared to 20% in the study population (P < 0.0001). 

Conclusions: The study findings show that compared to the general population, URTI in dialysis patients is a much more severe disease and has a higher complication rate. Influenza A, the most common pathogen, is associated with a worse prognosis.