INTRODUCTION — Dialysate leak can be a significant problem in patients treated with continuous peritoneal dialysis (PD) [1]. Dialysate can leak from the peritoneal space into an abdominal wall hernia or an extraperitoneal space such as the abdominal wall or genitalia (via a rent in the peritoneum or a patent processus vaginalis leak), the anterior abdominal wall (via a pericatheter leak), or the thorax (via a pleuroperitoneal leak).
A 2005 study of 1865 patients from the United States showed that hernias comprised approximately 60 percent of all anatomic complications of PD, with 41.4 percent inguinal, 31 percent umbilical, 23 percent ventral, 3.8 percent femoral, and 0.8 percent intrathoracic hernias [2]. An additional 25 percent of complications were due to either pericatheter or subcutaneous leaks, and 8 percent were due to hydrothorax.
Abdominal wall hernias and nonhernial dialysate leak in patients undergoing PD will be presented in this topic review. Other potential complications of PD are discussed elsewhere. (See "Noninfectious complications of peritoneal dialysis catheters" and "Peritoneal catheter exit-site and tunnel infections in peritoneal dialysis in adults".)
ABDOMINAL WALL HERNIA — Abdominal wall hernias are relatively common noninfectious complications in PD patients, with a prevalence rate of 4.2 to 27.5 percent and an incidence rate of 0.04 to 0.08 hernias per dialysis year [1,3-5].
Risk factors — The risk factors for hernia formation include:
●Polycystic kidney disease – Anatomic weakness may account for the apparently higher risk of abdominal hernia in patients with autosomal dominant polycystic kidney disease [2,5-7]. The abdominal wall abnormality may be secondary to the same process that results in the increased incidence of cerebral aneurysms, valvular disease, and diverticulosis in these patients. (See "Autosomal dominant polycystic kidney disease (ADPKD): Extrarenal manifestations".)
●Impaired wound healing – Metabolic factors also may play a contributory role. Examples include the adverse effects of malnutrition, uremia, and specific medications on wound healing and cellular proliferation [8].
●Poor rectus muscle tone and mass – This is more common in older adults, patients with obesity, and females with diabetes [9].
●Physical exertion – Further elevations of intra-abdominal pressure beyond that induced by dialysate instillation can be induced by increasing abdominal girth, changing from a supine to standing position, straining due to constipation, weight lifting, and leg lifting [10,11]. The highest pressures, up to 30 cm H2O, have been recorded with coughing. Therefore, efforts should be made to prevent increased abdominal pressure, especially in regard to avoiding constipation. (See 'Prevention' below.)
●Midline incision for PD catheter placement – The utilization of a paramedian approach to PD catheter insertion has significantly reduced the incidence of exit site and incision hernias from 10 to less than 1 percent per year [12]. (See "Placement of the peritoneal dialysis catheter", section on 'General principles'.)
Several other factors were deemed risk factors in some studies but not others:
●Sex – Females had 36 to 80 percent fewer hernias than males in two studies [1,2]; however, another study found a higher prevalence of hernia in multiparous females [13].
●Larger dialysate volume – The empty peritoneal cavity has an intra-abdominal pressure of 0.5 to 2.2 cm H2O; this value rises in direct proportion to the amount of fluid infused into the peritoneal cavity to on average 13.5 cm H2O with a two-liter instilled volume [10]. However, although an increased intra-abdominal pressure has been correlated with more hernias in some studies [14-16], other studies failed to show an increase in the rate of hernias in patients who are prescribed higher dwell volumes [1,2,10]. This indicates that hernias appear in sites of anatomic weakness and are not absolutely related to dwell volume.
Clinical manifestations — The sites of anatomic weakness that predispose to hernia formation include the inguinal canals, midline of the anterior abdominal wall (ie, linea alba, including umbilical and epigastric hernias), diaphragm, PD catheter exit site, and site of any prior surgical incision [1,3]. Symptoms associated with abdominal hernias in PD patients include painless swelling at different sites, discomfort or disfigurement, and problems related to a complication from the hernia.
Complications from abdominal wall hernias, including small bowel obstruction or intestinal incarceration and/or strangulation, are rare. Incarcerated hernias can be seen in the umbilical, inguinal, or incisional areas of the PD catheter [17]. Thus, underlying intestinal pathology should be considered in any patient with a hernia who develops peritonitis [18]. The presenting features of this complication are variable, ranging from tenderness at the site of the hernia sac to bowel perforation or obstruction. (See "Clinical features, diagnosis, and prevention of incisional hernias", section on 'Clinical features'.)
Diagnosis — Abdominal wall hernias are diagnosed clinically or by imaging studies. This is discussed in other topics. (See "Classification, clinical features, and diagnosis of inguinal and femoral hernias in adults", section on 'Diagnostic evaluation' and "Clinical features, diagnosis, and prevention of incisional hernias", section on 'Diagnosis'.)
Treatment — Patients who develop a hernia after the initiation of PD should undergo elective repair, if possible (algorithm 1).
Although there is evidence that asymptomatic patients may be safely observed [19] or managed with change from continuous ambulatory PD to low volume supine PD or automated PD [4], multiple studies have demonstrated the safety of hernia repair in patients who continue to undergo PD without significantly influencing residual renal function or PD technique survival [20-22]. As such, surgical repair is probably the prudent approach given the daily instillation of dialysate may enlarge the hernia over time, which may in turn complicate or interrupt PD [23].
Use of a polypropylene mesh prosthesis appears to decrease the risk of hernia recurrence and allows for the reinstitution of PD within several days of the hernia repair. In a retrospective review of 58 hernia repairs in 50 patients, recurrence rates were 12 percent without use of mesh and 0 percent with mesh hernioplasty [20]. With mesh repair, it is generally recommended that the mesh be placed extraperitoneally (either onlay or preperitoneal) to avoid contact with the dialysate [23]. For inguinal hernia repair, this can be accomplished using the open Lichtenstein technique [24,25], or alternatively, laparoscopic preperitoneal repair at the time of PD catheter placement [26]. For ventral hernias (most commonly umbilical or epigastric hernias), an open repair is recommended, as laparoscopic repair typically places an intraperitoneal mesh [23].
PD may frequently be resumed within several days of the herniotomy, using low-volume, supine, rapid cycling PD (which decreases intra-abdominal pressure) [20] with gradual reinstitution of the former PD regimen in the subsequent two- to four-week period [3,21,27,28]. At the University of Toronto, intermittent PD is begun 48 hours after surgery and PD is gradually reintroduced. In a retrospective study of 50 consecutive patients at this center, hemodialysis was not required in any patient, and leakage or early hernia recurrence was not observed [28]. The use of cough suppressants or laxatives, as needed, may decrease the risk of intermittent rises in intra-abdominal pressure [29].
DIALYSATE LEAK — Peritoneal dialysate leaks occur in up to 5 to 10 percent of patients on PD, and its incidence is dependent on PD catheter insertion techniques and the duration of PD [30-32].
Risk factors — The presence of dialysate fluid inside the peritoneal cavity increases intra-abdominal pressure and can lead to leaks due to congenital or acquired defects in the abdominal or thoracic wall and/or the diaphragm [33]. Known risk factors predisposing to fluid leaks are obesity, long-term steroid use, previous abdominal surgeries, and early use of the PD catheter [34-36].
Clinical manifestations — The migration of peritoneal fluid into adjacent body structures outside the peritoneum (ie, dialysate leakage) can lead to either abdominal wall or genital edema.
●In males, the testes descend into the scrotum via the processus vaginalis, which should then become obliterated. However, a patent processus vaginalis has been found in 90 percent of infants at birth and, at autopsy, in up to 37 percent of adults without hernias. Leakage of dialysate fluid into a patent processus vaginalis can result edema of the lower abdominal wall or genitalia [37,38], scrotal or labial swelling can be caused by dialysate flow through a patent processus vaginalis or the peritoneal membrane, followed by tracing of the fluid inferiorly into the scrotal or labial wall [39,40].
●Dialysate fluid can also traverse the peritoneal membrane into the soft tissues of the anterior abdominal wall, leading to abdominal wall edema [41]. Patients with this complication often present with increasing abdominal girth in conjunction with decreased peritoneal fluid drainage volume. Leaks are most commonly located in the pericatheter area [5,30] or prior surgical incisions including laparoscopic trocar sites.
●Additionally, hydrothorax is an uncommon (2 percent) but well-recognized complication of PD [42]. Hydrothorax is produced by movement of peritoneal dialysate through pleuroperitoneal fistulas [43]. 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 [44]. Pleural fluid analysis typically detects a high glucose concentration [45], and contrast imaging reveals tracer uptake transgressing the diaphragm. (See "Noninfectious complications of continuous peritoneal dialysis", section on 'Pleural effusion due to pleuroperitoneal leak'.)
Diagnosis — Several methods can be used to detect dialysate leak in PD patients. These are discussed in detail separately. (See "Modalities for the diagnosis of abdominal and thoracic cavity defects in patients on peritoneal dialysis".)
Treatment — Patients with peritoneal leaks without an associated hernia can initially be treated with either low-volume supine PD with a dry day or hemodialysis. The treatment of recurrent edema depends on the location (abdominal wall versus genital) (algorithm 1).
Initial leak — The patient with uncomplicated abdominal wall or genital edema (but without an associated hernia) should be treated conservatively with bed rest and temporary hemodialysis. A rest period of three to seven days may be sufficient for a pericatheter leak to heal, while it may take weeks for a noncatheter or nonprocedural-related abdominal wall leak to seal. In one study in which this technique was attempted for four weeks, the rate of relapse was 52 percent [5]; however, repeating this technique for an additional four weeks resulted in resolution of the leak in 86 percent of the remaining patients. (See "Noninfectious complications of peritoneal dialysis catheters", section on 'Pericatheter leakage'.)
Recurrent leak — Recurrent abdominal wall edema can be treated with a more prolonged course of hemodialysis (at least four to six weeks) or surgical repair. Surgery may be difficult if there is no obvious hernia present, since the site of the leak may not be defined. In this setting, imaging studies may help localize the defect [30,46,47]. (See "Modalities for the diagnosis of abdominal and thoracic cavity defects in patients on peritoneal dialysis".)
●A patent processus vaginalis should be surgically ligated as it is very unlikely to resolve without surgical intervention. This anatomic defect can be detected by technetium scanning, computed tomography (CT) with intraperitoneal contrast, magnetic resonance imaging (MRI) scanning without gadolinium, or surgical exploration [48,49].
●Migration of fluid via the anterior abdominal wall can be treated nonoperatively as previously described or surgically depending on the size and cause of abdominal wall leak (rent versus prior surgical site). This migration of fluid occurs via either small rents in the peritoneal membrane or a pericatheter leak. Imaging studies may help characterize the location and size of the leak, which may facilitate the discussion with patient about treatment options.
Hydrothorax — Hydrothorax due to a pleuroperitoneal leak is a potentially serious condition that can interrupt PD [50]. Based on the size of leak and patient symptoms, treatment options include various combinations of a conservative PD regimen, surgical intervention [51], and pleurodesis [52] if the patient desires to continue PD [44,53]. In some cases, the dialysate itself may serve as the pleurodesis agent [54,55]. This is discussed in detail elsewhere. (See "Noninfectious complications of continuous peritoneal dialysis", section on 'Management'.)
PREVENTION — Several measures can be taken before and during continuous PD to reduce the risk of hernia formation and dialysis leak. These include:
●In any individuals who have chosen PD as their dialysis modality, it is important to assess for preexisting hernias. In a study of 122 patients, 12 percent were found to have a hernia prior to the initiation of PD [3]. All identified hernias should be assessed for possible repair prior to initiating PD. In experienced hands, combined hernia repair and PD catheter placement does not lead to an increase in mortality, morbidity, or surgical complication rates compared with hernia repair prior to PD catheter placement. This has been shown for both ventral [3,56,57] and inguinal hernias [3,58].
However, if the hernia is assessed to be low risk for a complication such as bowel incarceration, hernia repair is not mandatory. It should be noted and discussed with the patient that PD may result in the hernia enlarging.
●Detection and ligation of a patent processus vaginalis can be performed during insertion of the PD catheter, especially laparoscopically [59].
●Place the PD catheter via a paramedian rather than a midline approach. (See "Placement of the peritoneal dialysis catheter", section on 'General principles'.)
●Placement of the deep cuff of the PD catheter in the rectus muscle with double purse-string sutures around the deep cuff [60,61].
●Placement of the PD catheter with rectus sheath tunneling to reduce pericatheter leakage [62,63].
●Liberal use of agents in the early postoperative period following PD catheter placement to prevent constipation and coughing. (See "Noninfectious complications of peritoneal dialysis catheters", section on 'Constipation'.)
●Allow a catheter break-in period of at least two weeks to heal the catheter exit site. Pericatheter fluid leakage is related to catheter break-in time. Patients who start their peritoneal exchanges within 72 hours of catheter placement (urgent-start PD) are more likely to have a pericatheter leak than those who start their PD exchanges one or two weeks after placement [64].
If dialysis is needed within the first two weeks (urgent-start PD), it can be provided with either the use of a low-volume (1.0 to 1.5 L), supine, rapid cycling (six exchanges per day) PD regimen or with hemodialysis. Hemodialysis is preferred if there are concerns about inadequate dialysis by using low-volume PD. (See "Urgent-start peritoneal dialysis".)
SUMMARY AND RECOMMENDATIONS
●Abdominal wall hernias – Abdominal wall hernias are relatively common noninfectious complications in peritoneal dialysis (PD) patients, with reported prevalence rates of 4.2 to 27.5 percent and incidence rates of 0.04 to 0.08 hernias per dialysis year. (See 'Risk factors' above.)
•Clinical manifestations – The sites of anatomic weakness that predispose to hernia formation include the inguinal canals, midline of the anterior abdominal wall (linea alba, including umbilical and epigastric hernias), diaphragm, PD catheter exit site, and site of any prior surgical incision. Symptoms associated with abdominal wall hernia in PD patients include painless swelling at different sites, discomfort or disfigurement, and problems related to a complication from the hernia, including small bowel obstruction or intestinal incarceration and/or strangulation. (See 'Clinical manifestations' above.)
•Treatment – For patients who develop a hernia after the initiation of PD, we suggest elective surgical repair rather than observation (Grade 2C). The use of a polypropylene mesh prosthesis placed extraperitoneally appears to decrease the risk of hernia formation postoperatively. Low-volume supine PD can often be resumed several days after surgical repair with gradual transition back to regular continuous ambulatory PD in two to four weeks (algorithm 1). (See 'Treatment' above.)
●Dialysate leak – Peritoneal dialysate leak without a hernia occur in up to 5 to 10 percent of patients on PD. (See 'Risk factors' above.)
•Clinical manifestations – The migration of peritoneal fluid into adjacent body structures (ie, dialysate leakage) can lead to either abdominal wall or genital edema. The sites of anatomic weakness that predispose to dialysate leak include a patent processus vaginalis, PD catheter exit site (pericatheter leak), and thorax (pleuroperitoneal leak). (See 'Clinical manifestations' above.)
•Treatment – For treatment of an initial dialysate leak, we suggest conservative management rather than surgical intervention (Grade 2C). This can be accomplished by either temporarily stopping PD; by changing to low-volume, supine, or dry day PD; or by a short-term transfer to hemodialysis.
For patients with recurrent genital edema, we perform imaging and surgical ligation of a patent processus vaginalis. Recurrent abdominal wall edema should be evaluated with imaging and can be treated with another longer pause of PD or surgical repair depending on findings on imaging. Hydrothorax due to a pleuroperitoneal leak is treated with thoracentesis, pleurodesis, thoracoscopy, or conversion to hemodialysis (algorithm 1). (See 'Treatment' above.)
●Prevention – Several measures can be taken before or during PD to reduce the risk of hernia formation and dialysis leaks, including evaluation and possible elective repair of existing hernias, the location and procedures used for PD catheter placement, a two-week break-in period before the start of PD, and methods to decrease intra-abdominal pressure in the postoperative period after PD catheter placement. (See 'Prevention' above.)
آیا می خواهید مدیلیب را به صفحه اصلی خود اضافه کنید؟