Influence of peritoneal dialysis catheter type on complications and long-term outcomes: an updated systematic review and meta-analysis.

BACKGROUND: There is currently no consensus regarding the optimal type of peritoneal dialysis catheter (PDC). We compared the outcomes of PDCs according to the number of cuffs, intercuff and intraperitoneal segment shape, and presence of a weighted tip. METHODS: A systematic review of the literature was performed using the MEDLINE and Cochrane Library databases (end-of-search date: October 16th, 2019). We included studies comparing double-cuff vs. single-cuff, swan-neck vs. straight-neck, coiled-tip vs. straight-tip, and weighted vs. non-weighted PDCs for the outcomes of interest. We performed meta-analyses using the random-effects model. We assessed the risk of bias using the Newcastle-Ottawa scale and the Cochrane Collaboration's Tool. RESULTS: In total, 38 studies were identified, of which 20 were randomized controlled trials (RCTs) and 18 were observational studies. No statistically significant differences were detected between double-cuff vs. single-cuff, swan-neck vs. straight-neck, and coiled-tip vs. straight tip PDCs in any of the outcomes of interest. Weighted catheters were associated with significantly lower rates of tunnel infection (relative risk [RR] 0.52, 95% confidence interval [CI] 0.31-0.95, p = 0.03), migration (RR 0.07, 95% CI 0.03-0.16, p < 0.001), drainage failure (RR 0.62, 95% CI 0.39-0.96, p = 0.03), cuff extrusion (RR 0.40, 95% CI 0.21-0.74, p < 0.001), and complication-related removal (RR 0.53, 95% CI 0.44-0.64, p < 0.001). DISCUSSION: Among the different types of PDCs, weighted catheters result in lower complication rates and superior long-term outcomes compared to non-weighted catheters. Other aspects of the catheter design do not significantly affect PDC outcomes. PROTOCOL REGISTRATION: PROSPERO 2020 CRD42020158177.

Hypovolemic Hyponatremia.

The etiology of hyponatremia is often multifactorial. The most common causes include hypovolemia from gastrointestinal (GI) or other fluid losses, thiazide diuretics, and SIAD [1]. In this chapter, we will discuss hypovolemic hyponatremia, as well as the clinical parameters that help distinguish between hypovolemic and euvolemic states. These include not only the urine [Na+] concentration but also the fractional uric acid excretion, a parameter that can be employed even when diuretics have been prescribed [2,3,4,5,6,7]. Among the common causes of hypovolemic hyponatremia are GI fluid loss, a range of endocrinopathies [7], and thiazide-induced hyponatremia, which is best considered as a distinct entity, in particular because recent data suggest that it has a genetic predisposition. Also, the discontinuation of thiazide is a key step in treatment [2,7]. The management of hypovolemic hyponatremia starts with confirming its presence and determining the underlying cause. Correction focuses on the appropriate use of isotonic fluid to effect volume repletion while avoiding an overly rapid rise in serum [Na+] concentration.