Daniela Ponce

Peritoneal Dialysis for Acute Kidney Injury

Renal Unit,1 Greys Hospital, Pietermaritzburg, South Africa; Renal and Intensive Care Units,2 Royal Devon and Exeter Hospital, Exeter, United Kingdom; Pediatric Nephrology Unit,3 Soba University Hospital, University of Khartoum, Sudan; Pondicherry Institute of Medical Sciences and Madras Medical Mission,4 Chennai, India; Department of Medicine,5 Botucatu School of Medicine, Sao Paulo, Brazil; Division of Nephrology-Hypertension,6 University of California, San Diego, USA; Division of Pediatric Nephrology,7 Shaare Zedek Medical Center, Jerusalem, Israel; Pediatric Nephrology Unit,8 Instituto da Criança of the Hospital das Clinicas of the University of Sao Paulo Medical School, Sao Paulo, Brazil; Pediatric Nephrology Department,9 Red Cross War Memorial Children’s Hospital, University of Cape Town, Cape Town, South Africa; Department of Surgery,10 Red Cross War Memorial Children’s Hospital, University of Cape Town, Cape Town, South Africa; School of Medicine,11 Pontificia Universidade Catolica do Parana, Curitiba, Brazil; Division of Pediatric Nephrology,12 University of Missouri-Kansas City School of Medicine, Kansas City, USA; Division of Nephrology,13 Queen’s University, Kingston, Canada; and Yale University,14 New Haven, USA ispd guidelines/ReCOMMendATiOns

Approach to prophylactic measures for central venous catheter‐related infections in hemodialysis: A critical review

Vascular access is the major risk factor for bacteremia, hospitalization, and mortality among hemodialysis (HD) patients. The type of vascular access most associated with bloodstream infection is central venous catheter (CVC). The incidence of catheter‐related bacteremia ranges between 0.6 and 6.5 episodes per 1000 catheter days and increases linearly with the duration of catheter use. Given the high prevalence of CVC use and its direct association with catheter‐related bacteremia, which adversely impacts morbidity and mortality rates and costs among HD patients, several prevention measures aimed at reducing the rates of CVC‐related infections have been proposed and implemented. As a result, a large number of clinical trials, systematic reviews, and meta‐analyses have been conducted in order to assess the effectiveness, clinical applicability, and long‐term adverse effects of such measures. In the following article, prophylactic measures against CVC‐related infections in HD patients and their possible advantages and limitations will be discussed, and the more recent literature on clinical experience with prophylactic antimicrobial lock therapy in HD CVCs will be reviewed.

Icodextrin reduces insulin resistance in non-diabetic patients undergoing automated peritoneal dialysis: results of a randomized controlled trial (STARCH)

BACKGROUND Insulin resistance is a common risk factor in chronic kidney disease patients contributing to the high cardiovascular burden, even in the absence of diabetes. Glucose-based peritoneal dialysis (PD) solutions are thought to intensify insulin resistance due to the continuous glucose absorption from the peritoneal cavity. The aim of our study was to analyse the effect of the substitution of glucose for icodextrin on insulin resistance in non-diabetic PD patients in a multicentric randomized clinical trial. METHODS This was a multicenter, open-label study with balanced randomization (1:1) and two parallel-groups. Inclusion criteria were non-diabetic adult patients on automated peritoneal dialysis (APD) for at least 3 months on therapy prior to randomization. Patients assigned to the intervention group were treated with 2L of icodextrin 7.5%, and the control group with glucose 2.5% during the long dwell and, at night in the cycler, with a prescription of standard glucose-based PD solution only in both groups. The primary end-point was the change in insulin resistance measured by homeostatic model assessment (HOMA) index at 90 days. RESULTS Sixty patients were included in the intervention (n = 33) or the control (n = 27) groups. There was no difference between groups at baseline. After adjustment for pre-intervention HOMA index levels, the group treated with icodextrin had the lower post-intervention levels at 90 days in both intention to treat [1.49 (95% CI: 1.23-1.74) versus 1.89 (95% CI: 1.62-2.17)], (F = 4.643, P = 0.03, partial η(2) = 0.078); and the treated analysis [1.47 (95% CI: 1.01-1.84) versus 2.18 (95% CI: 1.81-2.55)], (F = 7.488, P = 0.01, partial η(2) = 0.195). CONCLUSIONS The substitution of glucose for icodextrin for the long dwell improved insulin resistance measured by HOMA index in non-diabetic APD patients.

Advances in Peritoneal Dialysis in Acute Kidney Injury

Peritoneal dialysis (PD) is a simple, safe, cheap, and efficient renal replacement therapy method. It can correct metabolic disorders and fluid overload in acute kidney injury (AKI) patients both in and out of the intensive care unit. Use of PD in AKI is enhanced by placement of a Tenckhoff catheter, which can be safely accomplished at the bedside. Some PD modalities, such as high-volume PD and continuous-flow PD, can provide dialysis doses and efficiency comparable to extracorporeal blood purification methods. PD is particularly suitable for neonates, children, and patients with refractory heart failure or who are otherwise hemodynamically unstable. PD should be considered in situations where systemic anticoagulation and/or vascular access are problematic. PD is limited by a lower efficiency that may produce inadequate renal replacement in larger and/or severely hypercatabolic patients. Fluid removal can be unpredictable, there is a risk of infection, and possible issues with mechanical ventilation. In this article, we discuss the use of PD in AKI, with emphasis on recent advances.

Peritoneal Dialysis in Acute Kidney Injury: Brazilian Experience

Peritoneal dialysis (PD) was the first modality of renal replacement therapy (RRT) successfully used for patients with acute kidney injury (AKI) (1). In 1970, acute PD was widely accepted for AKI treatment, but its practice progressively declined in favor of hemodialysis techniques until, currently, PD is underutilized for AKI around the world (2–4). Recently, Brazilian experiences with PD in AKI have been published, and interest in using PD to manage selected AKI patients has been increasing. Here, we review recent literature and studies of PD for the treatment of AKI patients performed at the Botucatu School of Medicine, Sao Paulo State University, Brazil.

PERITONEAL DIALYSIS IN ACUTE KIDNEY INJURY: A VIABLE ALTERNATIVE

Acute kidney injury (AKI) is a common problem associated with increased mortality mainly in critically ill patients with multiple comorbidities admitted to the intensive care unit (1). Renal replacement therapy (RRT) is often necessary to maintain these patients alive. Adequacy of RRT for AKI has not yet been completely defined, but there is agreement that renal support therapies should provide correction of biochemical abnormalities, maintenance of fluid and electrolyte balance, and the capacity to maintain physiologic parameters within levels adequate to preserve organ function and to allow for functional recovery (2). Continuous RRT and intermittent hemodialysis (HD) are the modalities most commonly used in developed countries (3). Peritoneal dialysis (PD) for AKI is an underutilized modality worldwide, but it is frequently used in developing countries because of its lower cost and minimal infrastructure requirements (4,5). Recently, interest in using PD to manage patients with AKI has been increasing. The first question that must be asked is whether PD can provide adequate clearance in the treatment of patients with AKI. Our study group, from the Botucatu School of Medicine of Sao Paulo, Brazil, demonstrated that, with careful thought and planning, critically ill patients with AKI can be successfully treated with PD (6). To overcome some of the classic limitations of PD use in AKI, such as a low rate of ultrafiltration, high chance of infection, and no metabolic control, we proposed the use of cyclers, flexible catheters, and high volumes of dialysis fluid. Based on the characteristics of the peritoneal membrane, PD clearance is known to be limited by dialysate flow, membrane permeability, and membrane area. A 2-L exchange with a dwell time of approximately 30 minutes, as proposed by the authors, can achieve dialysate saturation of about 50%. Therefore, over 24 hours, application of a 2 L/hour regime can be expected to achieve an average clearance for urea of approximately 24 L. That calculation could lead to a Kt/V of 0.6 in a patient with a body weight of 65 – 70 kg. In the case of a continuous and daily regime, the weekly Kt/V would be 4.2, which is close to the value observed by the authors. In a comparison of this type of PD with daily intermittent HD involving a single-session Kt/V of 1, similar levels of standardized Kt/V can be achieved (5,7,8). That calculation provides the framework for the equivalency of intermittent HD and continuous PD in terms of smallmolecule clearance. In our study (6), an average urea clearance of 17.3 ± 5 mL/ min and a weekly delivered Kt/V of 3.85 ± 0.62 was achieved by using 2-L fill volumes and dwell times of 65 – 80 minutes, with glucose concentrations of 2.0% being used in more than half the patients. Previous studies have often reported using smaller dialysate volumes and shorter dwell times, thus compromising clearances (9,10). In our study in critically ill patients, serum urea was controlled after 4 sessions of continuous PD; 2 patients suffered minor leaks, but no other mechanical problems; and no respiratory compromises were reported. Those results suggest that careful prescription and accurate measurement of dialytic efficiency may contribute to providing adequate treatment in most AKI patients without contraindications to PD use. However, it is also true that PD is not the most efficient therapy for all AKI patients, because clearance per exchange can be lower if a shorter dwell time is applied. Nevertheless, other aspects of treatment should be considered, including the lower efficiency typically observed in larger and severely hypercatabolic patients, the limited capacity to modulate fluid removal with PD, the high risk for infection, and the possibility that PD may worsen mechanical ventilation, leading to impaired respiratory or cardiac performance (5,6,9,10). The second question that is specifically relevant to the paper by George et al. (11) from Medical College Hospital, Kerala, India, in this issue of Peritoneal Dialysis International, is whether PD is comparable to other dialysis methods in AKI patients. The answer to that question is neither simple nor currently complete. Despite a significant attempt to find the optimal therapy, the average mortality of patients with AKI has not been clearly seen to improve in recent years (12). Therapies provide renal support rather than complete renal replacement, because they offer only a partial and limited substitution of the multiple functions of the kidney (13), and patients are becoming extremely complex. One generalized prescription for therapy cannot therefore be reasonably made for all individuals (14).

Acute kidney injury after massive attack of Africanised bees

Acute kidney injury (AKI) is a well-documented complication of massive attack by Africanised bees and can be observed 48–72 h after the accident. We report a case of Africanised bees attack followed by severe and lethal AKI. A 56-year-old man was admitted to emergency department after a massive attack of Africanised bees (>1000 bee stings). He was unconscious, presenting with hypotension and tachycardia. Mechanical ventilation, volume expansion and care for anaphylaxis were instituted. The patient was transferred to the intensive care unit (ICU) and after 48 h he developed rhabdomyolysis, oliguria, increased creatinine levels, hyperkalaemia and refractory acidosis. A diagnosis of AKI secondary to rhabdomyolysis and shock was made. The patient was treated with a prolonged course of haemodialysis. However, he progressed to refractory shock and died 5 days after admission.

Effective Use of Alteplase for Occluded Tunneled Venous Catheter in Hemodialysis Patients

Despite their propensity for significant infectious and mechanical complications, tunneled central venous catheters (CVCs) have become a common means of vascular access in the world for patients requiring chronic hemodialysis for end-stage renal disease. The objective of this study was to explore if cryopreserved solutions of the thrombolytic agent alteplase could be used as an effective, safe, and economically reasonable alternative in hemodialysis patients with occluded tunneled CVC. Patients requiring chronic hemodialysis and presenting with occluded tunneled CVC received a sufficient volume of the alteplase solution to fill the occluded catheter. To make alteplase economically feasible, it was diluted to 1-mg/mL aliquots and they were stored at -20°C until use. Eighty-one patients accounting for 179 attempted clearances were assessable for efficacy. One hundred forty-seven (82.1%) of the 179 catheter clearance attempts resulted in successful catheter clearance after one dose. Twenty-seven (15.1%) of all occluded CVCs were successful after two doses whereas five (2.8%) were not. No adverse events were reported. Cryopreserved 1-mg/mL aliquots of alteplase are safe and effective in the clearance of occluded CVC for hemodialysis patients.

Long-term outcome of patients followed by nephrologists after an acute tubular necrosis episode

Aims of our study were to describe the long-term survival in patients surviving an acute tubular necrosis (ATN) episode and determine factors associated with late mortality. We performed a prospective cohort study that evaluated the long-term outcome of 212 patients surviving an ATN episode. Mortality at the end of followup was 24.5%, and the probability of these patients being alive 5 years after discharge was 55%. During the followup, 4.7% of patients needed chronic dialysis. Univariate analysis showed that previous CKD (P = 0.0079), cardiovascular disease (P = 0.019), age greater than 60 years (P < 0.0001), and higher SCr baseline (P = 0.001), after 12 months (P = 0.0015) and 36 months (P = 0.004), were predictors of long-term mortality. In multivariate analysis, older age (HR = 6.4, CI 95% = 1.2–34.5, P = 0.02) and higher SCr after 12 months (HR = 2.1, 95% CI 95% = 1.14–4.1, P = 0.017) were identified as risk factors associated with late mortality. In conclusion, 55% of patients surviving an ATN episode were still alive, and less than 5% required chronic dialysis 60 months later; older age and increased Scr after 12 months were identified as risk factors associated with late death.

Inflammation and overweight in peritoneal dialysis: is there an association?

More than 30% of the patients on peritoneal dialysis show chronic systemic inflammatory activity with high levels of C-reactive protein. The purpose of this cross-sectional study was to investigate the influence of the inflammatory state on clinical and nutritional markers in patients on peritoneal dialysis. Twenty-seven patients were included: mean age was 57.6 ± 19 years, 48% were male, and median time on peritoneal dialysis was 16.0 (8.3; 35.8) months. Clinical, dialytic, laboratory, anthropometric and electric bioimpedance data were collected with the sample stratified for C-reactive protein. In patients, the levels of Interleukin-6 and tumor necrosis factor-α were higher, while adiponectin levels were lower than in healthy individuals (p ≤ 0.001), indicating the presence of inflammatory activity in the sample. When compared to patients with C-reactive protein <1 mg/dL, those with ≥1mg/dL showed higher body mass index (29.4 ± 6.1 vs. 24.4 ± 4.5 kg/m2; p = 0.009), percent of standard body weight (124.5 ± 25.4 vs. 106.8 ± 17.9 %; p = 0.012), and percent of body fat as assessed by both anthropometry (31.3 ± 9.9 vs. 23.9 ± 9.1%; p = 0.056) and bioimpedance (38.9 ± 6.3 vs. 26.2 ± 12.6 %; p < 0.001). Patients with C-reactive protein ≥1mg/dL also exhibited higher levels of ferritin (701 ± 568 vs. 532 ± 356 ng/mL; p =0.054) and lower total lymphocyte count (median 1838 vs. 1638 mm3; p = 0.001). In conclusion, higher body mass index and body fat markers were associated with C-reactive protein ≥ 1mg/dL, and higher C-reactive protein was associated with immunocompetence impairment evidenced by the lower total lymphocyte count. Our findings confirm the relationship between inflammation, body fat, and immunocompetence, which may be superimposed potentializing the inflammatory status.