Tidal continuous cycling peritoneal dialysis in children

About 10% of all home peritoneal dialysis regimens in children with chronic kidney disease stage 5 are reported to involve some form of a tidal peritoneal dialysis (TPD) prescription. Despite this, there remain several gaps in how pediatric nephrologists approach the use of TPD. This stems from a combination of factors such as the confusing technical terminology pertaining to TPD, seemingly conflicting data on the risks, benefits, and indications for TPD, and lastly, limited published guidelines on the practical aspects of how to write a TPD prescription, based on the indication, in children. Our educational review, using evidence-based data, attempts to bridge this gap and provide an easy-to-use guide on the key practical aspects of TPD in children.

Diagnostic and therapeutic management of hydrothorax in peritoneal dialysis

Hydrothorax is a rare mechanical complication of peritoneal dialysis (PD) which often results in discontinuation of the technique. According to studies, its incidence is estimated  at 1.6 to 2%. In the majority of cases, its location is on the right. It is secondary to the passage of dialysate from the peritoneal cavity to the pleural space through a diaphragmatic breach, which may be acquired or congenital. The additional tests necessary to confirm the diagnosis are often invasive and expensive, and are not the subject of any consensus. It is the same for the therapeutic management, which goes from the simple transient interruption of the dialysis to heavy treatments such as thoracotomy. In our center, we have opted to simplify the management of patients with hydrothorax. From a diagnostic standpoint, we use simple, minimally invasive and less expensive examinations. For the therapeutic management, we have opted, since our first case in 2000, for a simple and less aggressive surgical technique, with an abdominal and non-thoracic approach allowing the installation of a sub-diaphragmatic prosthesis by laparoscopic route to seal the lesions breaches. Out of 10 operated patients, 2 (20%) presented with a relapse of hydrothorax and were permanently transferred to hemodialysis. The remaining 8 (80%) were able to resume PD without subsequent recurrence or complications, after a 3- to 4-week PD interruption period during which all patients were hemodialyzed through a simple central catheter.  

The Occurrence of Increased Intraperitoneal Volume Events in Automated Peritoneal Dialysis in the US: Role of Programming, Patient/User Actions and Ultrafiltration

Background, objectives and methods

Increased intraperitoneal volume (IIPV) can occur during automated peritoneal dialysis (APD). The contribution of factors such as cycler programming and patient/user actions to IIPV has not been previously explored. The relationship between IIPV and cycler programming, patient/user actions, and ultra-filtration over a two-year period was investigated using US data from Baxter cyclers. Drain/fill volume ratios of > 1.6 to ≤ 2.0 and > 2.0 were defined as Level I and Level II IIPV events, respectively.

Results

Level I IIPV events occurred in 2.39% of standard and 4.73% of small fill volume therapies, while Level II IIPV events occurred in 0.26% and 1.33% of therapies, respectively. IIPV events occurred significantly more often in association with tidal peritoneal dialysis (PD) compared to non-tidal PD therapies. In tidal therapies, IIPV events were primarily related to suboptimal programming of total ultrafiltration volume. Factors that increased the odds of IIPV events during standard therapies included programming the initial drain volume target to < 70% of the last fill, and setting minimum drain volumes to < 85% of the fill volume. Bypass of initial drain by patients/users was also associated with a significant increase in the odds of IIPV events in non-tidal, but not tidal PD. An increase in the odds for IIPV was also seen for standard therapies within the highest (> 1,245 mL) versus the lowest (< 427 mL) quartile of ultrafiltration. Similar trends were seen in small fill volume therapies. Clinical presentations associated with IIPV events were not assessed.

Conclusions

IIPV events are more frequent in tidal and small fill volume therapies. The greatest potential for IIPV occurred when the total ultrafiltration was set too low for the patient's UF requirements during tidal therapy. Patient/user bypass of drains without reaching the target drain volume contributes significantly to IIPV events in non-tidal PD therapies. Poorly functioning PD catheters may be central to the cycler programming and patient/user actions that lead to IIPV.

Thoracoscopic surgery for management of pleuroperitoneal communication complicating continuous ambulatory peritoneal dialysis: A case report

RATIONALE

Pleuroperitoneal communication (PPC) has been reported to complicate continuous ambulatory peritoneal dialysis (CAPD). However, cases of patients in whom the results of the methylene blue dye test and peritoneopleural scintigraphy were negative and treatment was thoracoscopic surgery have been rarely reported.

PATIENT CONCERNS

A 58-year-old man with end-stage chronic renal failure who underwent CAPD presented with massive right-sided hydrothorax. The pleural fluid glucose level was high. Results of both the methylene blue dye test and peritoneopleural scintigraphy were negative.

DIAGNOSIS

The presence of end-stage chronic renal failure and diaphragm defects amenable to repair, which were identified during thoracoscopic surgery, indicated a definite diagnosis of PPC complicating CAPD.

INTERVENTIONS AND OUTCOMES

CAPD was performed twice after the defects were repaired during thoracoscopic surgery. There was no evidence that the repaired sites were leaking again, and the patient did not complain of any discomfort during the second CAPD.

LESSON

Although special methods such as the methylene blue dye test and peritoneopleural scintigraphy may not be useful in some cases, thoracoscopic surgery is still effective and reliable in diagnosing and repairing diaphragmatic defects.

The management of neonatal acute and chronic renal failure: A review

Most babies with chronic renal failure are identified antenatally, and over half that are treated with peritoneal dialysis receive kidney transplants before school age. Most infants that develop acute renal failure have hypotension following cardiac surgery, or multiple organ failure. Sometimes the falls in glomerular filtration and urine output are physiological and reversible, and sometimes due to kidney injury, but (illogically) it is now common to define them all as having 'acute kidney injury'. Contrary to widespread opinion, careful interpretation of the plasma creatinine concentrations can provide sensitive evidence of early acute renal failure. Conservative management frequently leads to under-nutrition or fluid overload. Acute peritoneal dialysis is often technically fraught in very small patients, and haemotherapies have been limited by vascular access and anticoagulation requirements, the need to blood-prime circuits, and serious limitations in regulating fluid removal. Newer devices, including the Nidus, have been specifically designed to reduce these difficulties.

Pleuro-peritoneal or pericardio-peritoneal leak in children on chronic peritoneal dialysis-A survey from the European Paediatric Dialysis Working Group

BACKGROUND

Pleural or pericardial effusions secondary to pleuro-peritoneal fistula (PPF) and pericardio-peritoneal fistula (PcPF) are rare but serious complications of peritoneal dialysis (PD).

METHODS

We conducted a 10-year survey across all participating centres in the European Paediatric Dialysis Working Group to review the incidence, diagnostic techniques, therapeutic options and outcome of children on chronic PD with PPF and/or PcPF.

RESULTS

Of 1506 children on PD there were ten cases (8 of PPF, 1 each of PcPF and PPF + PcPF), with a prevalence of 0.66%. The median age at presentation was 1.5 [inter-quartile range (IQR) 0.4-2.4] years, and nine children were <3 years. The time on PD before onset of symptoms was 4.3 (IQR 1.3-19.8) months. Eight children had herniae and seven had abdominal surgery in the preceding 4 weeks. Symptoms at presentation were respiratory distress, reduced ultrafiltration and tachycardia. PD was stopped in all children; three were managed conservatively and thoracocentesis was performed in seven (with pleurodesis in 3). PD was restarted in only three children, in two of them with success.

CONCLUSION

In conclusion, PPF and PcPF are rare in children on chronic PD, but are associated with significant morbidity, requiring a change of dialysis modality in all cases. Risk factors for PPF development include age of <3 years, herniae and recent abdominal surgery.

Haemodialysing babies weighing <8 kg with the Newcastle infant dialysis and ultrafiltration system (Nidus): comparison with peritoneal and conventional haemodialysis

BACKGROUND

To compare the efficacy of the Newcastle infant dialysis and ultrafiltration system (Nidus) with peritoneal dialysis (PD) and conventional haemodialysis (HD) in infants weighing <8 kg.

METHODS

We compared the urea, creatinine and phosphate clearances, the ultrafiltration precision, and the safety of the Nidus machine with PD in 7 piglets weighing 1-8 kg, in a planned randomised cross-over trial in babies, and in babies for whom no other therapy existed, some of whom later graduated to conventional HD.

RESULTS

Two babies entered the randomised trial; 1 recovered rapidly on PD, the other remained on the Nidus as PD failed. Additionally, 9 babies were treated on the Nidus on humanitarian grounds: 3 because of failed PD, and 3 with permanent kidney failure later converted to conventional HD. We haemodialysed 10 babies weighing between 1.8 and 5.9 kg for 2,475 h during 354 Nidus sessions without any clinically important incidents, and without detectable haemolysis. Single-lumen vascular access was used with no blood priming of circuits. The urea, creatinine and phosphate clearances using the Nidus were around 1.5 to 2.0 ml/min in piglets and babies, and were consistently higher than PD clearances, which ranged from about 0.2 to 0.8 ml/min (p ≤ 0.0002 for each chemical). Ultrafiltration was achieved to microlitre precision by the Nidus, but varied widely with PD. Fluid removal using conventional HD was imprecise and resulted in some hypovolaemic episodes requiring correction.

CONCLUSION

The Nidus can provide HD in the Pediatric Intensive Care Unit (PICU) and outpatient intermittent HD without blood priming for babies weighing <8 kg, It generates higher dialysis clearances than PD, and delivers more precise ultrafiltration control than either PD or conventional HD.

Hydrothorax: pleural effusion associated with peritoneal dialysis

Hydrothorax in a patient treated with peritoneal dialysis (PD) poses a diagnostic dilemma. Hydrothorax due to migration of dialysis fluid across the diaphragm and into the pleural space creates a serious complication of PD but generally does not threaten life. Shortness of breath causes the patient to seek medical attention. A sudden diminution in dialysis adequacy or poor ultrafiltration rate constitutes a unique marker for patients treated with PD compared to the general population. This article reviews the etiology for hydrothorax specifically in the PD population. Thoracentesis with chemical analysis of the fluid, imaging studies with and without contrast or markers, and video-assisted thoracoscopic surgery play important roles in the evaluation of hydrothorax. A conservative PD regimen, surgical intervention, and pleurodesis provide treatment options to those receiving PD.

Relationship between drain volume/fill volume ratio and clinical outcomes associated with overfill complaints in peritoneal dialysis patients

BACKGROUND

To better understand the spectrum of overfill reports and their corresponding clinical severity and etiology, we conducted a review of overfill reports from the Manufacturer and User Facility Device Experience (MAUDE) database, which is within the Food and Drug Administration (FDA) Web site (www.fda.gov).

METHOD

We searched the MAUDE database for events related to overfill reports between 1 January 1995 and 31 December 2008 and recorded drain volume (DV)/fill volume (FV), or DV/FV, and clinical symptoms and signs associated with the overfill report.

RESULTS

Among 462 MAUDE reports with a possible overfill event, 440 reports (95.2%) with a confirmed overfill event contained sufficient information to ascertain the clinical severity of the event. The number of reports with a clinical severity rating of minor, moderate, major, or death was 331, 71, 28, and 10, respectively. The median (range) DV/FV for a subgroup of 292 reports with a clinical severity rating of minor, moderate, major, or death was 1.63 (1.06 - 4.29), 1.71 (1.08 - 5.87), 2.14(1.64 - 2.61), and 2.50 (2.28 - 3.33), respectively. Insufficient drain accounted for a majority of overfill reports.

CONCLUSION

Our analysis of reports from the MAUDE database suggests an association between DV/FV and clinical severity of the reported overfill event, as well as significant patient-to-patient variability with respect to intraperitoneal volume tolerance.

Dialysate leakage into pericardium in an infant on long-term peritoneal dialysis

We report on a 2-year-old boy on automated peritoneal dialysis (PD) with a history of multiple hernias and dialysate leaks who developed pericardial effusion. Magnetic resonance imaging (MRI) demonstrated a peritoneo-pericardial fistula. Dialysis had to be discontinued, since head-down tilt reproducibly induced significant hypotension. In PD patients with pericardial effusion a peritoneo-pericardial leak should be considered.