Peritoneovenous shunt occlusion. Etiology, diagnosis, therapy

Symptomatic Fluid Drainage: Peritoneovenous Shunt Placement

Ascites causes significant discomfort and has negative impact on patient's quality of life. Medical therapies including dietary restriction and diuretics are successful in only 40 to 44% of patients with malignant ascites and repeated paracentesis only provides temporary symptomatic relief. Therefore, a more permanent solution is necessary. Indwelling catheters or peritoneovenous shunt placement can provide more permanent symptomatic relief and improve patients' quality of life. Unlike indwelling catheters, peritoneovenous shunts do not limit patients' life style and therefore should be offered as first option in patients who are good candidates. Denver shunt (CareFusion-BD Worldwide) is the current available peritoneovenous shunt. In this article, the indications, contraindications, technical aspects of shunt placement, and techniques to prevent postprocedure complications will be discussed.

Modified saphenous-peritoneal shunt in refractory ascites: new technique

BACKGROUND

Refractory ascites is a serious complication for patients with decompensated liver cirrhosis. Saphenous-peritoneal shunting is a possible surgical treatment for its relief, but tends to lead to higher groin infections. The purpose of the present paper was to determine whether a modified procedure could resolve the problem and offer potential advantages over a peritoneo-venous shunt.

METHODS

Sixteen patients with refractory ascites who received modified saphenous-peritoneal shunts were studied. Clinical data such as bodyweight, abdominal girth, indocyanine green 15-min retention rate (ICG-15), serum bilirubin concentrations, Child-Pugh Score, creatinine clearance (C(Cr)), daily urinary output, urine sodium (U(Na)) and operative complications were recorded before, and 3 months after, surgery.

RESULTS

Three months after the operation, the urinary output, nutritional status and Child-Pugh scores had improved, but ICG-15 and total bilirubin output had not changed significantly. The C(Cr), U(Na) bodyweight and abdominal girth tended to decrease, but not significantly. No groin infections were noted following this procedure.

CONCLUSIONS

This modified procedure not only improved the nutritional status of cirrhotic patients with refractory ascites but also improved their quality of life. Infections and obstructions decreased in the short term. However, long-term follow up is mandatory. This new technique requires more practice and experience.

Treatment of symptomatic primary chylous disorders

PURPOSE

Primary chylous disorders (PCDs) are rare. Rupture of dilated lymph vessels (lymphangiectasia) may result in chylous ascites, chylothorax, or leakage of chyle through chylocutanous fistulas in the lower limbs or genitalia. Chyle may reflux through incompetent lymphatics, causing lymphedema. To assess the efficacy of surgical treatment, we reviewed our experience.

METHODS

The clinical data of 35 patients with PCDs treated between January 1, 1976, and August 31, 2000, were reviewed retrospectively.

RESULTS

Fifteen men and 20 women (mean age, 29 years; range, 1 day-81 years) presented with PCDs. Sixteen (46%) patients had chylous ascites, and 19 (54%) had chylothorax (20 patients), and of these, 10 (29%) had both. In 16 patients, reflux of chyle into the pelvic or lower limb lymphatics caused lymphedema (14, 88%) or lymphatic leak through cutaneous fistulae (11, 69%). Presenting symptoms included lower-limb edema (19, 54%), dyspnea (17, 49%), scrotal or labial edema (15, 43%), or abdominal distention (13, 37%). Primary lymphangiectasia presented alone in 23 patients (66%), and it was associated with clinical syndromes or additional pathologic findings in 12 (yellow nail syndrome in 4, lymphangiomyomatosis in 3, unknown in 3, Prasad syndrome (hypogammaglobulinemia, lymphadenopathy, and pulmonary insufficiency) in 1, and thoracic duct cyst in 1). Twenty-one (60%) patients underwent 26 surgical procedures. Preoperative imaging included computed tomography scan in 15 patients, magnetic resonance imaging in 3, lymphoscintigraphy in 12, and lymphangiography in 14. Fifteen patients underwent 18 procedures for chylous ascites or pelvic reflux. Ten (56%) procedures were resection of retroperitoneal/mesenteric lymphatics with or without sclerotherapy of lymphatics, 4 (22%) were lymphovenous anastomoses or grafts, 3 (17%) were peritoneovenous shunts, and 1 (6%) patient had a hysterectomy. Six patients underwent eight procedures for chylothorax, including thoracotomy with decortication and pleurodesis (4 procedures), thoracoscopic decortication (1 patient), ligation of thoracic duct (2 procedures), and resection of thoracic duct cyst (1 patient). Postoperative mean follow-up was 54 months (range, 0.3-276). Early complications included wound infections in 3 patients, elevated liver enzymes in 1, and peritoneovenous shunt occlusion with innominate vein occlusion in 1. All patients improved initially, but four (19%) had recurrence of symptoms at a mean of 25 months (range, 1-43). Three patients had postoperative lymphoscintigraphy confirming improved lymphatic transport and diminished reflux. One patient died 12 years postoperatively, from causes unrelated to PCD.

CONCLUSIONS

More than half of the patients with PCDs require surgical treatment, and surgery should be considered in patients with significant symptoms of PCD. Lymphangiography is recommended to determine anatomy and the site of the lymphatic leak, especially if lymphovenous grafting is planned. All patients had initial benefit postoperatively and two thirds of patients demonstrated durable clinical improvement after surgical treatment.

Saphenoperitoneal shunts for patients with intractable ascites associated with chronic liver disease

BACKGROUND

Ascites is a common complication in patients with chronic liver disease. Some patients are resistant to diuretics and need therapeutic paracentesis on a regular basis. This is inconvenient in the long term and also has resource implications. Alternatively, these patients may be treated by peritoneovenous shunts, which require insertion of a foreign body into a central vein and are prone to occlusion. A new technique for peritoneovenous shunting without the use of foreign material is described.

METHODS

Eight patients with chronic liver disease and diuretic-resistant ascites underwent this procedure. During operation, the long saphenous vein was divided at the mid-thigh level and inverted towards the inguinal canal, where it was anastomosed directly to the peritoneum at the internal inguinal ring using non-absorbable suture material.

RESULTS

Seven patients had successful shunt formation; the remaining patient had to have the shunt removed because of ascitic leakage. In those who underwent successful shunt formation, the need for paracentesis and the dose of diuretic was significantly reduced over a median follow-up of 8 months. Hospital stay in the month after discharge was significantly less than that in the month before operation. Three patients died during follow-up from causes unrelated to the operation. One patient underwent successful liver transplantation.

CONCLUSION

This study suggests that saphenoperitoneal shunting is potentially a safe and effective therapy for patients with diuretic-resistant ascites. It retains the benefits of peritoneovenous shunting without the adverse effects of insertion of foreign material.

Management of ascites in cirrhosis

Ascites is one of the earliest and most common complications of patients with cirrhosis. A typical circulatory dysfunction characterized by arterial vasodilation, high cardiac output and stimulation of vasoactive systems is commonly present in these patients and is associated with a poor prognosis. The treatment of ascites has been based on the combination of a low-sodium diet and the administration of diuretics. The reintroduction of paracentesis and the recent introduction of the transjugular intrahepatic portosystemic shunt (TIPS) are the most relevant innovations in the treatment of ascites during the past two decades, although controlled trials in large series of patients are needed to delineate whether TIPS is a safe and useful treatment for these patients.

Role of surgical therapy in management of intractable ascites

Almost 10% of patients with cirrhosis and ascites develop intractable ascites. When large-volume paracentesis fails to relieve ascites, patients may be submitted to one of the three following surgical options: portosystemic shunting, peritoneovenous shunting, or liver transplantation. Portosystemic shunting is efficient in clearing ascites, but it is associated with a high rate of encephalopathy and liver failure. The indications for portosystemic shunting are therefore limited for treatment of intractable ascites and should be performed only in patients with good liver function in whom all other treatments failed. Peritoneovenous shunting has been associated with a high rate of early complications and valve obstruction. Improvements in perioperative care and in the material used have greatly reduced the operative risks and increased the patency rate. Mortality remains high in patients with severe liver failure or with a history of spontaneous bacterial peritonitis or variceal bleeding. Peritoneovenous shunting should not be done when these risk factors are present. In the absence of such risk factors, peritoneovenous shunting is a good procedure and may provide definitive relief of ascites and long-term survival in more than 50% of the operated patients. In patients with poor risk factors liver transplantation may be preferable, and the onset of intractable ascites in a patient with a severely compromised liver should trigger the indication of liver replacement.

The effects of positive expiratory pressure on peritoneovenous shunt flow

Cirrhotic patients with peritoneovenous shunts may require mechanical ventilation. Despite the importance of flow to shunt patency and the relevance of intrathoracic pressure to that flow, the relationship between shunt flow and positive airway pressure has not been documented. To study the effects of positive expiratory pressure (PEEP) on shunt flow, models of ascites (n = 8) were created in adult male mongrel dogs. Each animal was anesthetized, intubated, and mechanically ventilated. Peritoneovenous shunts with in-line electromagnetic flow meters were surgically placed. Shunt flow, central venous pressure (CVP), and intraabdominal pressure (IAP) were monitored. Initial intraabdominal pressures were adjusted by infusion of warmed saline and positive expiratory airway pressures were added in increments. Changes in pressures (IAP, CVP) and shunt flow were tabulated and analyzed with linear and polynomial regression. Intraabdominal and central venous pressures increased linearly with PEEP at different rates such that IAP-CVP varied inversely with PEEP. Shunt flow varied inversely as a polynomial function of PEEP. Analyses of these relationships allowed creation of a nomogram which can be interpolated to indicate required intraabdominal pressure needed to maintain shunt flow throughout the clinically useful range of positive airway pressure.

Denver shunt causing abnormal right atrial mass: noninvasive determination of shunt patency by color-coded Doppler shuntography

An unusual floating mass was detected in the right atrium of a 71-year-old man with liver cirrhosis and intractable ascites using two-dimensional echocardiography. The mass was caused by the venous tip of a Denver peritoneovenous shunt. Shunt patency could be assessed easily by compression of the pump body; this maneuver resulted in a laminar or turbulent flow that was recorded at the tip of the shunt in the right atrium by color-coded Doppler echocardiography. We are reporting the first case demonstrating the value of echocardiography in diagnosing a Denver shunt in the heart and shunt patency by color-coded Doppler shuntography.

Current medical management of cirrhotic ascites

The presence of ascites may indicate a number of hepatic and extra-hepatic disorders. This situation requires comprehensive evaluation to determine the underlying cause. The evaluation and management of ascites in patients with known cirrhosis is very important since this manifestation of portal hypertension has a detrimental effect on the prognosis for such patients.

Chylothorax secondary to obstruction of the superior vena cava: a complication of the LeVeen shunt

A case of thrombosis of the superior vena cava was complicated by bilateral chylothoraces and a widened mediastinum. Removal of a clotted LeVeen shunt led to prompt resolution of the obstruction and chylothoraces.

Peritoneovenous shunting as compared with medical treatment in patients with alcoholic cirrhosis and massive ascites. Veterans Administration Cooperative Study on Treatment of Alcoholic Cirrhosis with Ascites

The optimal management of severe ascites in patients with alcoholic cirrhosis has not been defined. in a 5 1/2-year study, we randomly assigned 299 men with alcoholic cirrhosis, who had persistent or recurrent severe ascites despite a standard medical regimen, to receive either intensive medical treatment or peritoneovenous (LeVeen) shunting. We identified three risk groups: Group 1 had normal or mildly abnormal results on liver-function tests, Group 2 had more severe liver dysfunction or previous complications, and Group 3 had severe prerenal azotemia without kidney disease. For the patients who received the medical treatment and those who received the surgical treatment combined, the median survival times were 1093 days in Group 1, 222 days in Group 2, and 37 days in Group 3 (P less than or equal to 0.01) for all comparisons). For all the groups combined, the median time to the resolution of ascites was 5.4 weeks for medical patients and 3.0 weeks for surgical patients (P less than 0.01). Within each risk group, mortality during the initial hospitalization and median long-term survival were similar among patients receiving either treatment. However, the median time to the recurrence of ascites in Group 1 was 4 months in medical patients, as compared with 18 months in surgical patients (P = 0.01); in Group 2 it was 3 months in medical patients as compared with 12 months in surgical patients (P = 0.04). The median duration of hospitalization was longer in medical patients than in surgical patients (6.1 vs. 2.4 weeks in Group 1 [P less than 0.001] and 5.0 vs. 3.1 weeks in Group 2 [P less than 0.01]). Group 3 was too small to permit a meaningful comparison. During the initial hospitalization, the incidence of infections, gastrointestinal bleeding, and encephalopathy was similar among the medical and surgical patients. We conclude that peritoneovenous shunting alleviated disabling ascites more rapidly than medical management. However, survival was closely related to the severity of the illness at the time of randomization and was not altered by shunting.

Persistent haemorrhagic ascites in generalised haemolymphangiomatosis: a therapeutic dilemma

Images

[Diagnosis of peritoneovenous shunt occlusion]

Reaccumulation of ascitic fluid after peritoneovenous shunt implantation demands accurate diagnostic procedure. Between 1973 and 1985 81 peritoneovenous shunts have been implanted at the IInd Surgical Department of the University of Vienna. In the same time 34 reoperations in 17 patients have been performed for reasons of shunt-dysfunction. Besides thorax x-ray, diagnosis was established in 11 cases by means of Doppler ultrasound investigation, in 26 cases by technetium scan and in 15 cases by shunt angiography. Shuntography proved to be the method of choice, with no false results. Doppler ultrasound results were unclear in a high percentage, thus this method is not used any more.

Coagulopathy post peritoneovenous shunt

In 1942, 53% of medically treated patients with cirrhosis were dead 6 months after the onset of ascites. Only 30% survived 1 year. This dismal outlook has improved only slightly with advances in medicine. Yet, some internists reject the peritoneovenous shunt (PVS) for this fatal condition even if they are aware that a diminished blood volume causes the abnormal sodium retention responsible for ascites. Their objections are based on life-threatening complications of PVS, especially post shunt coagulopathy (PSC). Blood shed into the peritoneal cavity becomes incoagulable. Such blood is immediately coagulated by a protocoagulant (soluble collagen) and concurrently lysed by tissue plasminogen activator (TPA) secreted by the peritoneal serosa. Wide zones of lysis surround peritoneal tissue placed on fibrin plates. Large volumes of ascitic fluid infused into circulating blood simulates the fate of blood shed into the peritoneal cavity with lysis playing the major role. Addition of ascitic fluid to normal platelet-rich plasma in vitro initiates clot lysis on thromboelastogram (TEG). Epsilon-aminocaproic acid (EACA) counteracts this lysis. EACA and clotting factors normalize the TEG and arrest PSC. Disposal of ascitic fluid at surgery prevents or ameliorates PSC. Mild PSC was encountered only twice in 150+ consecutive patients (1.3%) with only one case being clinically significant (0.6%). Severe PSC occurred seven times in 98 early shunt patients whose ascitic fluid was not discarded. Severe PSC requires shunt interruption and control of bleeding with clotting factors and EACA. Peritoneal lavage with saline prevents the recurrence of PSC on reopening the shunt. In four patients, EACA and clotting factors were adequate to arrest coagulopathy. Three earlier patients died of PSC before its cause and treatment were understood. Proper management eliminates this life-threatening complication, and PSC cannot be considered a deterrent to PVS. Disseminated intravascular coagulopathy (DIC) is produced in experimental animals only by the injection of thrombin or thromboplastin. PSC is a distinct entity differing from DIC; EACA and not heparin is the antidote for PSC.

Denver peritoneovenous shunting for malignant or cirrhotic ascites. A prospective consecutive series

A Denver peritoneovenous (PV) shunt was inserted in 54 consecutive patients for relief of malignant (24 patients) or cirrhotic (30) refractory ascites. The median age of both groups was 58 years, and the most frequent diagnoses were gastrointestinal (15) or ovarian (7) cancers and alcoholic cirrhosis (25). Median survival time was 1.7 and 3.5 months (range, 0.1-15.5 and 0.1-50.5), and the 1-month mortality 42% and 27%, respectively. Postoperative 24-h urinary output increased by 2-31, and the 1-week weight reduction was 8 and 11 kg, respectively, compared with before shunting. Complete shunt failure was encountered early in two patients, due to catheter malposition and clotting. Four more patients experienced transient failure, for an early dysfunction rate of 11%. A shunt-related operative mortality of 6% was caused by pulmonary oedema (two patients) and sepsis (one patient). Shunt malfunction intervened in almost half (6 of 14) of the cancer patients surviving 1 month but was relieved in all but 1. In 3 of 22 cirrhotic 1-month survivors, the Denver shunt had to be removed owing to clotting or sepsis (2 patients) or revised because of blockage. Seven patients with cirrhosis are alive a median of 18 months (range, 2-51) after PV shunt surgery. Side effects were detected in 22 patients (41%): thromboembolism (9 patients), sepsis (7), initially bleeding oesophageal varices (3), DIC syndrome (2), postoperative hepatic coma (2), ascitic leakage (2), and pulmonary oedema (2). Patients with gastrointestinal cancers or severe cardiac disease did not benefit from the procedure. A history of hepatic encephalopathy or a serum bilirubin level above about 100 mumol/l was a bad prognostic sign. We could confirm the reported considerable morbidity and mortality after PV shunting, but also its efficiency in certain cases. Careful patient selection and follow-up study, timing of operation, and adherence to technical details are mandatory to improve the results.

Intracardiac thrombus causing peritoneovenous shunt failure: detection by two-dimensional echocardiography

Peritoneovenous shunts have become an accepted mode of therapy for ascites refractory to medical treatment. However, their use is known to be associated with significant morbidity and mortality. Reported is the case of a patient with a Denver shunt who developed massive intracardiac thrombosis and subsequent shunt malfunction, despite preserved shunt patency.

The LeVeen shunt in the elective treatment of intractable ascites in cirrhosis. A prospective study on 140 patients

One hundred and forty patients with an intractable ascites complicating a chronic liver disease received a peritoneovenous shunt (PVS) using the LeVeen valve. Operative mortality was ten per cent but was 25% in patients with severe liver failure. Intraoperative drainage of ascites sharply decreased postoperative complications and mortality. One-year actuarial survival rate was 81.4%, respectively 77.7%, 61.3%, and 24.7% in patients with good liver function and moderate or severe liver failure. Variceal hemorrhage occurred in 11 patients and late infection in another 11 patients. Thirty-eight patients (30.5%) had recurrence of ascites. This was mostly due to an obstruction on the venous side of the shunt. An elective portacaval shunt had to be done in 23 patients for recurrence of ascites or variceal bleeding. Among the 57 patients still alive at time of writing, 51 were free of ascites. These results suggest that PVS is an efficient operation. This procedure may be largely indicated in the selected and small group of cirrhotic patients with true intractable ascites and moderate or no liver insufficiency.

Management of complications of portal hypertension

The management of portal hypertension focuses on control of its complications, the most important of which is bleeding esophageal varices. Other complications, such as ascites, bleeding intestinal stomas, and hypersplenism, rarely require surgical intervention. Other than medical management, the three basic procedures now available for the treatment of bleeding esophageal varices include decompression of varices with a portosystemic shunt, nonshunting operations that attack directly the esophageal variceal-bearing area, and liver transplantation as the procedure of choice in selected patients. Patients who present with episodes of acute bleeding are usually treated initially with medical therapy including acute sclerotherapy or balloon tamponade techniques when necessary. If the patient fails to respond or if episodes of bleeding recur, further therapy is required. Although selection of therapy remains controversial, it is based on multiple factors. These include the basic pathogenic mechanism of portal hypertension in the individual patient, status of the patient as defined by Child's classification, elective or urgent nature of the operation, hemodynamic stability of the patient at the time of the procedure, site of the block in the portal system, and caliber and anatomic relationship of the vessels available for anastomosis in the portal system. Additional factors include the presence and severity of ascites or encephalopathy, age of the patient, site of bleeding (esophageal or gastric), severity of associated hypersplenism, and techniques and expertise available at a given institution. Shunting procedures achieve the best long-term control of bleeding, but they can precipitate the development of encephalopathy. Nonshunting procedures do not induce encephalopathy, but they are usually associated with a high rate of rebleeding. Also, with the possible exception of sclerotherapy, they are still associated with a high operative mortality rate in alcoholic patients classified as Child's C. Although sclerotherapy controls acute variceal bleeding more successfully than conventional methods, it is not readily applicable in patients with bleeding gastric varices. Also, it has not yet clearly been proved to be an effective method of permanent control of gastroesophageal bleeding and has not been demonstrated to increase survival. The new methods of extensive esophagogastric devascularization (for example, porta-azygos disconnection using the Sugiura procedure) are attractive because of the low late recurrence rate for bleeding without the induction of encephalopathy.(ABSTRACT TRUNCATED AT 400 WORDS)