Extrahepatic portal hypertension in children

Extrahepatic portal hypertension in children

Extrahepatic Portal Hypertension in Children Long-Term Evaluation E. Thomas Boles, Jr., MD, Columbus, Ohio William E. Wise, Jr., MD, Columbus, Ohio G...

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Extrahepatic Portal Hypertension in Children Long-Term Evaluation

E. Thomas Boles, Jr., MD, Columbus, Ohio William E. Wise, Jr., MD, Columbus, Ohio Gary Birken, MD, Columbus, Ohio

Knowledge of many aspects of extrahepatic portal hypertension in children remains incomplete at best. The condition is relatively uncommon, so that experience on any one service is small compared with the experience of intrahepatic portal hypertension associated with cirrhosis in adults. No clinical prospective series have been reported, and its cause remains poorly defined. The natural history of the condition is not well understood, since usually one or several forms of intervention cloud the issue. The reported success of various forms of therapy vary considerably, as do the incidence and severity of long-term complications. The purpose of this report is to analyze the long-term status of a group of children with extrahepatic portal hypertension with particular reference to the effectiveness of surgical procedures and the long-term complications. Patients and Methods Forty-three children with extrahepatic portal hypertension have been managed in the division of pediatric surgery from 1950 to 1985. No significant difference in incidence between the sexes was found, with 24 boys and 19 girls included in this group. Etiologic factors which could result in portal venous thrombosis were present in 12 children (28 percent). These included neonatal omphalitis in eight, exchange transfusion therapy in three, and neonatal sepsis in one. A total of 31 shunting procedures were performed in 28 of these patients, 22 of which were performed on our service. Nine were performed elsewhere and were later managed at our institution only after failure became evident. From the Division of Pediatric Surgery, Department of Surgery. Ohio State University College of Medicine and Children’s Hospital and Children’s Hospital Research Foundation. Columbus, Ohio. Requests for reprints should be addressed to E. Thomas Boles. Jr., MD, Department of Pediatric Surgery, Children’s Hospital, 700 Children’s Drive, Columbus, Ohio 43205.

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Splenorenal shunts: Thirteen patients had splenorenal shunts, 10 of which were performed at our institution. Of these 10, most were of the central type in which the most proximal segment of the splenic vein is used [I]. Eight of the 10 have been long-term successes, with follow-up periods varying from 8 to 28 years (average followup 151/zyears). In one of the patients with an unsatisfactory shunt, the shunt was created at 8 years of age, but the patient began hemorrhaging 4 years later. A resection was then carried out, with no further bleeding during the subsequent 26 years. In the second patient with a failed shunt, the shunt was created when the patient was 7 years old and bleeding recurred within a year. Sclerotherapy was then successfully employed, with no bleeding for the next 5’/2 years. Age at the time of shunt in these 10 patients varied from 4 to 17 years; three were under 6 years of age, and the remainder were all over 7 years of age (average 9 years). The diameter of the shunts was measured in six patients and varied from 9 to 14 mm. Preshunt and postshunt mesenteric venous pressures were measured in seven paGents, and satisfactory decreases were noted in all of them. In four patients, the postshunt. pressure was below 20 cm saline solution. In two, the pressure was slightly above this figure and in one, the pressure was 32 cm, a decrease from 56 cm. The flow through the shunt at operation was judged to be good in all 10 patients. No real differences in these parameters between patients with satisfactory shunts and those with failed shunts were noted, except that the postshunt mesenteric venous pressure in one of the patients with a nonfunctioning shunt was the highest recorded (32 cm saline solution). No deaths or significant morbidity other than further bleeding in the two patients with failed shunts occurred in this group. The follow-up period in the eight patients with patent shunts has varied from 9 to 28 years. Recent esophagrams obtained from four patients showed no varices. Mesocaval shunts: Ten children had side-to-end mesocaval shunts, seven of which were performed on our service. The superior mesenteric veins were normal without thrombotic involvement in all seven. The shunts were technically satisfactory in all seven, and good flow

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through the shunt was observed in all but one. Pressures were reclorded before and after the procedure in four, and decreases in pressure that varied from 8 to 24 cm saline solution were recorded. The postshunt pressures were 17, 22, 26, and 32 cm saline solution, respectively. The child whose postshunt pressure was 32 cm saline solution showed the largest decrease (24 cm saline solution) from the preshunt, level. The patient ages at operation varied from 4’/~ to 11 years of age. Six of the seven have had no further bleeding, and all are alive and in good health. Only three esophagrams have been recently obtained, all of which showed no abnormalities. Various complications in the lower extremities were common, and these will be discussed separately. The shunt fa.iled in one patient who rebled 14 months later. At the time of the shunt in this 11 year old patient, the superior mesenteric vein was of good quality and the shunt was technically good; however, blood flow through the shunt was poor, even after a revision. A resection carried out 3 years later was successful, with no further bleedin;: in the intervening 11 years. In addition, a 19 year old patient received an interposition mesocaval shunt using a short length of a 20 mm woven Dacron@ prosthesis. A satisfactory decrease in mesenteric venous pressure was noted. This patient has had no further bleeding over a follow-up period of 9 years. An arteriogram 2 months postoperatively demonstrated a patent, functioning shunt, and a recent esophagram demonstrat’ed no varices. Makeshift shunts: This term applies to shunts other than the standard procedures, used invariably because no vein in the portal system was suitable for a conventional shunt. There were a total of seven such shunts performed in six patients, four of these performed at our institution. In one ‘of these four, a coronary to left renal vein anastomosis was performed at 5 years of age. Bleeding recurred 7 years later, and relatively infrequent episodes of bleeding continued for 12 years. The patient was 31 years of age and had not bled for over 7 years at last follow-up, although varices are present both radiographically and on endoscopy. He was in good health and working regularly. The other three such shunts performed at our institution wlere all attempted side-to-end mesocaval shunts. The superior mesenteric vein in these three patients was involved in a thrombotic process, and a collateral of the vein was used for the mesenteric end of the shunt. In earlier reports [2,3], these patients were classified as having mesocaval shunts, but the makeshift. category is clearly more precise. None were technically satisfactory, and all eventually failed, with rebleeding within 2 years. Direct operations: These are procedures in which control of the varices is attempted either by resection, interruption of t.he flow to the varices by gastric or esophageal division together with interruption of the gastroesophageal venous tributaries, or by direct ligation of varices. Sclerotherapy also falls into this group. Resections. A total of nine resections with interpositions have heen performed, seven at our hospital. In two cases, the entire thoracic esophagus together with the fundu!; of the stomach was removed and a substernal colonic interposition performed. Both patients had undergone previous operations; in one patient, ligation of varices and a subsequent splenectomy had been performeld elsewhere, and in the second, a mesocaval shunt performed at our institution had failed. Both have had

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periods of 14 years after the resect,ions without further bleeding. In the other five patients with resections performed at our institution, the lower fourth to third of the thoracic esophagus plus the fundus of the stomach were removed. A colonic interposition was used in four, and a segment of jejunum was used as an interposition in one. In one, performed at 12 years of age after failure of a splenorenal shunt, there has been no further bleeding for 21 years, and the patient is in excellent health. The other four have failed. One child had the resection performed at 18 months of age. A mesocaval shunt was subsequently performed at 41/z years of age, and he has had no further bleeding for 22 years and is free of varices. Another had the resection at 3 years of age, and had no further bleeding for 13 years; however, in the past 12 years, this 28 year old patient has had several relatively minor episodes of bleeding. Endoscopy 3 years ago showed an ulceration of the interposed colon just above the gastric junction, and this may well be the source of bleeding. A makeshift type of mesocaval shunt performed in a 10 month old child failed, and a resection with jejunal interposition was performed at 3 years of age. The patient has had occasional bleeding episodes in the 30 years since the resection, although his general health is good and he is working regularly. The final failure may in fact represent a good result. This patient had four procedures carried out elsewhere, including a splenectomy and three shunting procedures at other hospitals in the first 10 years of life. A resection with colon interposition performed at our institution was successful for 3 years, at which time a bleeding episode occurred. The exact bleeding source was not identified, but 15 years later at last follow-up the patient was in excellent health and without further bleeding. One of the patients in whom resection was carried out elsewhere received a makeshift type of mesocaval shunt performed at our institution at 13 years of age that subsequently failed. After a number of subsequent bouts of hemorrhage, a resection with jejunal int.erposition was carried out elsewhere at 29 years of age. She had been free of bleeding for the subsequent 13 years at last follow-up. The second of the patients who had an interposition procedure at another hospital first had a splenorenal shunt performed in her local hospital at 12 years of age. This failed, and a laparotomy was carried out in our institution 2 years later in an effort t.o perform another shunt. This was not possible, and subsequent bleeding occurred. Two resections were carried out 10 and 14 years later elsewhere, but in the subsequent 6 years she has had another episode of hemorrhage. Portoazygous disconnection. Five patients had this procedure or some modification of it. Posrtoazygous disconnection involves gastrotomy and ligation of varices from within the stomach as well as gastric transection with anastomosis in an effort to interrupt the collateral veins feeding the varices. Although these operations often have provided significant hemorrhage-free periods, bleeding has eventually recurred in all. Clearly, this type of procedure can be viewed only as temporary. In one 5 year old child who underwent this procedure, intermittent variceal bleeding continued for I4 years, but none has occurred in the last 6 years. In a second patient, a splenorenal shunt, done elsewhere at 6 years of age failed. Portoazygous disconnection was performed at our institution 41/2 years later because the superior mesenteric vein was

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shown to be unsuitable for a shunt. Multiple episodes of bleeding have since occurred, and sclerotherapy was initiated 3 years earlier with control achieved. Her overall health at 32 years of age on last follow-up was good. The third child underwent a similar procedure at 8 years of age, again because both the splenic and superior mesenteric veins were involved in the thrombotic process. After a respite of 5 years, the patient again experienced bleeding periodically for 12 years but surprisingly, she has had none for the last 5 years. At last follow-up she was in good health, working regularly, and was progressing through an uncomplicated pregnancy. The fourth child underwent portoazygous disconnection at 7 years of age because the splenic and superior mesenteric veins were deemed too small for a good shunt. Bleeding recurred in 3% years. After further bleeding episodes, a splenorenal shunt procedure was carried out at 17 years of age. This was successful with no further bleeding in the ensuing 8 years. In the fifth patient, a modified portoazygous disconnection was performed at 16 years of age because no suitable vein in the portal system was available for a shunt. A splenectomy had been performed previously at 5 years of age. Three months later, acute liver failure developed and the patient died. Postmortem examination showed acute hepatic necrosis, presumably caused by serum hepatitis. Miscellaneous operations. A number of miscellaneous procedures were carried out. Transesophageal ligation of varices was performed in two patients at other hospitals. One temporarily controlled the bleeding, and a later resection was performed at 29 years of age. In the second, bleeding was not controlled, and the child was transferred to our hospital in an hemodynamically unstable state. He arrived moribund and died shortly after arrival, with no response to resuscitative measures. Two patients had splenic artery ligations alone performed in an effort to decrease flow through the varices. One was performed in a 7 year old child because the splenic and superior mesenteric veins were involved in the thrombotic occlusive process, but bleeding recurred 21 months later. The second child had undergone splenic transplantation to the left chest elsewhere at 3 years of age, after which chronic thrombocytopenia developed. Six years later, the thrombocytopenia became severe, with platelet counts ranging from 10,000 to 20,000 cells/ mm3 and with clinical evidence of purpura. The decision was made to remove the spleen and perform a splenorenal shunt. During the operation, anuria, thought to be caused by a transfusion reaction, developed, and the operation was terminated after a splenic artery ligation only. The patient recovered in the immediate postoperative period and was sent home 10 days later in apparently satisfactory condition. However, he died suddenly at home 3 days later. The most impressive finding at autopsy was severe medial hypertrophy of the pulmonary arterioles and right ventricular hypertrophy, indicating pulmonary hypertension. Interestingly, there were no vascular collaterals between the spleen and the lung, chest wall, or diaphragm. Sclerotherapy. This procedure has been used in seven of our patients during the past 6 years [4]. Six had previous procedures that had failed, including splenectomy in two, a splenorenal shunt in one, a mesocaval shunt in one, a makeshift shunt in one, and a splenic artery ligation in one. A tragic death occurred in the child who had a failure

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of a makeshift shunt and is described further in the section on mortality. Another had obliteration of varices with endosclerosis over a 4 month period. Six months later, varices recurred, and were again obliterated after further sessions over a period of 13 months. No further recurrence has been noted. Complete control of further bleeding has been accomplished in the six survivors. Splenectomy. Splenectomy as an isolated procedure was performed in 12 patients, 3 at our institution. Indications included hypersplenism in four, splenomegaly with varices in five, questionable isolated splenic vein thrombosis in one, splenomegaly in one, and unknown in one. In retrospect, these indications leave much to be desired. Most of the procedures were carried out in young patients, eight of whom were 5 years old or younger. The operation failed in terms of preventing future bleeding in all. In eight, bleeding occurred within 3 years postoperatively, although this interval was more than 10 years in three patients. Methods to control later bleeding included mesocaval shunts in three, a makeshift shunt in one, resection in three, portoazygous disconnection in one, and sclerotherapy in three. Obviously, no splenorenal shunts could be performed. Postoperative sepsis has not occurred in these patients, despite the obvious risk of this complication [5]. No definitive surgical treatment: Five patients have been followed regularly without the performance of any definitive operation. The most notable of these has been followed since infancy, during which time ascites and failure to grow occurred. Laparotomy at 7 months of age confirmed extrahepatic portal hypertension. An intraoperative portal venogram showed no normal splenic or superior mesenteric veins, many small collateral vessels in the porta hepatis, and filling of gastric and esophageal varices. She had several episodes of bleeding from infancy until 11 years of age, but she was 28 years old at last follow-up and has had no bleeding in 17 years. Furthermore, she has no splenomegaly and only a few small irregularities in the distal esophagus on esophagraphy. In this patient, complete or almost complete regression of portal hypertension appears to have occurred. In the other four patients, variceal bleeding has continued to occur at intervals. One had a diagnostic laparotomy at 5 years of age with pressure measurements and portal venography. She was free of further bleeding for 15 years, at which time she was hospitalized elsewhere with acute variceal bleeding. A splenectomy only was carried out because of a reltively low portal venous pressure of 30 cm saline solution. At last follow-up, this 29 year old patient was in good health but with radiographic evidence of esophageal varices. The third had a splenectomy at 8 months of age, at which time both the splenic and superior mesenteric veins were found on venography to be replaced by multiple small collaterals. Intermittent bleeding episodes continued for 29 years. Sclerotherapy was begun 3 years ago with no further bleeding. The fourth patient, now 22 years of age, began at 2 years of age with bleeding episodes. A laparotomy was performed at 13 years of age, at which time no portal venous tributary appropriate for a shunt was found. His last episode of bleeding was 6 years ago, but he still has splenomegaly and large varices are demonstrated on esophagography. The last patient had a splenectomy carried out elsewhere at 15 years of age. Continued bleeding episodes over the

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year was the indication for beginning sclerotherapy. She has been free of bleeding in the subsequent 5 years.

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Results Six of these patients have died, three from complications directly related to the portal hypertension. In one patient previously described, acute liver failure (developed with resulting death secondary to serum hepatitis. This occurred 3 months after portoazygous disconnection. The second had undergone a :makeshift shunt at 9 years of age, and sclerotherapy was begun 2 years later. Several months after starting the sclerotherapy, she and her family moved to a distant locality. A severe variceal bleeding episode was successfully managed by a gastric transection elsewhere, but unfortunately the patient died secondary to hypoxic brain damage caused by respiratory complications in the immediate postoperative period. The third patient, also noted previously, died from hemorrhage after transesophageal ligation of varices and a poorly timed transfer to our hospital. The fourth patient also died from bleeding. A splenic artery ligation had been performed at 7 years of age. At age 14, massive gastrointestinal bleeding occurred that was managed with blood replacement, vasopressin, and gastroesophageal tamponade, to no avail. As steps were underway for an emergency laparotomy within 3 to 4 hours of transfer, he died. Autopsy showed the source of bleeding to be a large gastric ulcer, and another finding of interest was pulmonary arteriolar hyperplasia consistent with pulmonary hypertension. The fifth patient has already been noted. He died 10 days after a splenic artery ligation, the operation being aborted because of a possible transfusion reaction. His death occurred unexpectedly at home, and the finding of evidence of pulmonary hypertension at autopsy was remarkable. The last patient committed suicide due to a drug overdose at 25 years of age. She had been free of bleeding for 11 years after resection of the thoracic esophagus and upper stomach with a colonic interposition. Complications: The morbidity of repeated bleeding episodes, hospitalizations, and operations is evid.ent. Eighteen of the patients had a total of 47 operations, not including sessions of sclerotherapy. A number of complications followed the various procedures, most of them known to represent a risk from these types of operations. Among those directly related to therapy, venous complications of the lower extremities occurred in 5 of the 12 patients who had undergone inferior vena cava division. Lower limb varicosities developed in one patient, and deep venous thrombosis with stasis and varicosities developed in another. Two have had occasional episodes of phlebitis, and the last has a more chronic type of phlebitis that requires compression dressings. None have been incapacitated.

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Serum hepatitis developed in two patients and was fatal in one of them. Three patients have shown evidence of pulmonary hypertension. Two of these died and have been discussed already. In one, pulmonary hypertension and right-sided heart failure probably were responsible for death. The third such patient was 25 years of age at last follow-up. A mesocaval shunt at 6 years of age was followed by disappearance of the varices and no further bleeding. In the past 3 years, the patient has been evaluated because of intermittent respiratory infections and chest pain. Cardiologic evaluation including two-dimensional. echocardiograms and a radioisotope nuclide study showed dilatation and hypertrophy of the right ventricle and other findings interpreted as clear evidence of pulmonary vascular disease. The cause of pulmonary arterial hypertension in these patients is not known. Possibly microemboli to the pulmonary arterial system that originate from the portal venous thrombotic process may play a significant role [6]. Present status: Thirty-four of these patients have been followed for more than 5 years and can be reasonably appraised in terms of long-term results. Nineteen have had no bleeding for 8 to 18 years. They are generally in excellent health without evidence of portal hypertension or esophageal varices. However, three have varicosities or phlebitis in the lower extremities, and one has evidence of pulmonary arterial hypertension. Fifteen have had shunts, splenorenal shunts in 8 and mesocaval shunts in 7. Three have had resection with interposition operations, and the final one has had no definitive procedure whatever. This latter patient is the only example in the series of spontaneous resolution of portal hypertension. Fifteen patients continue to have problems of varying degrees from their portal hypertension. Ten have undergone unsuccessful definitive operations, and the remaining five have had no such procedures. Among those 10 who have had previous operations, 6 have had no bleeding in more than 5 years (1 for 28 years), whereas the other 4 continue to have periodic episodes of bleeding. Three of those with no definitive procedures have not bled in at least 3 years, whereas the other two have experienced bleeding more recently. None of the survivors have shown any obvious evidence of neuropsychiatric disturbances. The one patient who died from a drug overdose at 25 years of age had a difficult family and social history, as well as significant past problems with alcohol and drugs. In addition, she did not have a functioning shunt. Comments The major problem caused by extrahepatic portal hypertension is hemorrhage from esophageal varices. Ascites may occur in infancy, sometimes asso-

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TABLE I

Direct Operations

Procedures

Success

Failure

Esophageal resections Total Lower Portoazygous disconnection Sclerotherapy (short-term)

2 1 0 6

0 4 5 1

2 5 5 7

Total

9

IO

19

Total

ciated with transient growth failure, and occasionally develops after a significant bleeding episode in older children. Splenomegaly due to chronic congestion and associated with a variable degree of hypersplenism may also be the initial clinical manifestation, but neither ascites nor splenomegaly account for significant morbidity. Treatment for a single episode of acute hemorrhage is straightforward. Usually, the bleeding stops with bed rest, blood replacement, and sedation. At times, vasopressin or esophageal tamponade may be needed. Rarely is a surgical procedure necessary to stop the bleeding. Indeed, if these measures are not successful, the diagnosis should be called into question and endoscopy strongly considered. A more challenging problem is the prevention of repeated hemorrhage. A number of approaches to this goal have been advocated, and various types of portal to systemic venous shunts are available. Unquestionably, a well-constructed shunt is highly successful, as is evident from our long-term success rates of 80 and 88 percent with splenorenal and mesocaval techniques respectively. We have carried out 10 splenorenal shunts, 8 successful and 2 unsuccessful, and 8 mesocaval shunts, 7 successful and 1 unsuccessful, for an overall success rate of 83 percent. Although the reported success rates with splenorenal and mesocaval shunts vary considerably, excellent results have been reported by several groups [7-91. With a patent shunt, episodes of hemorrhage cease and the varices disappear or decrease markedly in size. The opportunity to perform a satisfactory shunt was limited by involvement of the splenic and superior mesenteric veins in the thrombotic process in 10 of the children in this series. There are disadvantages to both of the standard operations. With the central splenorenal technique, the spleen is removed, and the patient is thereby vulnerable to the infrequent but often devastating complication of postsplenectomy sepsis [5]. The risk can be decreased by active immunization against multiple strains of pneumococcus. In the mesocaval shunt procedure, the distal inferior vena cava is divided, and the patient is at risk for the development of venous stasis in the lower limbs. This has been common in our experience, although

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considerably less so in other reports [10,11]. Finally, both shunts totally divert portal blood away from the liver. The risk of subsequent neuropsychiatric problems as a consequence of hepatic encephalopathy was discussed by Vorhees et al [12], who found a very high incidence in their long-term evaluation; however, neither our experience nor that of several other workers [13,14], have confirmed this complication as a significant risk. Makeshift shunts are usually performed in desperation and have been of little or no value in our experience. They should be abandoned. Direct procedures such as portoazygous disconnection have been disappointing except as temporary measures [15]. Resections of the distal or entire thoracic esophagus and fundus of the stomach with an interposition are better, but have succeeded in only about half the cases in our experience (Table I). Since such procedures have usually followed the failure of some other operation, they are often technically difficult. Furthermore, ulceration in the interposed segment of colon adjacent to the gastric anastomosis has been a troublesome later complication in two patients. The extensive devascularization procedure described by Sugiura and Futagawa [16] has had remarkably good results, but to date we have no experience with this operation. Splenectomy, like makeshift shunts, is useless as a measure to prevent further bleeding and should not be performed as an isolated operation. Rarely, if ever, does the hypersplenism associated with this form of splenomegaly justify removing the spleen. Furthermore, the operation exposes the child to the risk of postsplenectomy sepsis. Finally, the splenic vein becomes unavailable for a future shunt. Sclerotherapy has become very popular in recent years, and excellent control of varices in children has been reported [17-191. Our own recent experience with this technique has been encouraging, and a number of patients in this series were so treated. Long-term evaluation, however, is not yet possible. During adult life in those patients with failed operations or none at all, the frequency of bleeding episodes has shown a distinct tendency to decrease. These patients are for the most part in good health, active, and productive. However, spontaneous resolution of extrahepatic portal hypertension is rare. Summary A long-term evaluation of 43 children with extrahepatic portal hypertension indicates a high success rate and excellent subsequent health when a splenorenal or mesocaval shunt can be performed. On the other hand, makeshift shunts inevitably fail. Direct operations are considerably less successful than standard shunts. Esophagogastric resections with interpositions result in long-term freedom from bleeding in only about half the cases, and portoazy-

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gous disconnection procedures have been uniformly disappo:inting. Sclerotherapy in a relatively recent experience has been quite successful, but long-term results are presently unavailable. The condition carries a significant mortality rate. Complications from failed-operations, division of the vena cava, and multiple transfusions are numerous.

The general health of long-term survivors is excellentk those with successful operations, and is surprisi:ngly good for patients whose operations have been unsuccessful and for those who have had no operations. References 1. Clatworthy HW Jr, Boles ET Jr. Extrahepatic portal bed block in children: pathogenesis and treatment. Ann Surg 1959;150:371-83. 2. Clatworthy HW Jr. Extrahepatic portal hypertension. In: Child CG, ed. Major problems in clinical surgery, vol. 14. Philadelphia: WB Saunders, 1974:243-86. 3. Boles ET Jr, Birken G. Extrahepatic portal hypertension in children. Chir Pediatr 1983;24:23-38. 4. Vane DW, Boles ET Jr, Clatworthy HW Jr. Esophageal sclerotherapy: an effective modality in children, J Pediatr Surg 1985;20:703-7. 5. Singer DB. Postsplenectomy sepsis. In: Rosenberg HS. Bolande RP, eds. Perspectives in pediatric pathology, vol. I. Chicago: Year Book Medical Publishers, 1973:285-311. 6. Cohen MD, Rubin LJ, Taylor WE, Cuthbert JA. Primary pulmonary hypertension: an unusual case associated with extrahepatic portal hypertension. Hepatology 1983;3:588-92.

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7. Voorhees AB Jr, Price JB. Extrahepatic ports1 hypertension. Arch Surg 1974;108:338-41. 8. Bismuth H, Franc0 D, Alagille D. Portal diversion for portal hypertension in children: the first 90 patients. Ann Surg 1979;192:18-24. 9. Coran AG, Wesley JR, Weintraub WH. The central splenorenal shunt for portal hypertension in children: experience with eight consecutive patent anastomoses. J Pediatr Surg 1980;15:827-34. 10. Auvert J, Weisgerber G. Immediate and long-term results of suoerior mesenteric vein-inferior vena cava shunt for mortal hypertension in children. J Pediatr Surg 1975;10:9Oi-8. 11. Lambert MJ III, Tank ES, Turcotte JG. Late sequelae of mesocaval shunts in children. Am J Surg 1974; 127:19-24. 12. Vorhees AB Jr, Chaitman E, Schneider S. et at. Portal-svstemic encephalopathy in the noncirrhotic patient. Arch Surg 1973;107:659-83. 13. Grauer SE, Schwartz SI. Extrahepatic portal hypertension: a retrospective analysis. Ann Surg 1979;189:566-74. 14. Fonkalsrud EW, Myers NA, Robinson MJ. Management of extrahepatic portal hypertension in children. Ann Surg 1974;180:487-91. 15. Tanner NC. The late results of porto-azygos disconnection in the treatment of bleeding from oesophageal varices. Ann R Coll Engl 1961;28:153-74. 16. Sugiura M, Futagawa S. A new technique for treating esophageal varices. J Thorac Cardiovasc Surg 1973;66:677-85. 17. Lilly JR, Stiegmann GV, Stellin G. Esophageal endosclerosis in children with portal vein thrombosis, J Pediatr Surg 1982; 17:571-5. 18. Howard ER, Stamatakis JD, Mowat AP. Management of esophageal varices in children by injection sclerotherapy. J Pediatr Surg 1984;19:2-5. 19. Paquet KJ, Oberhammer E, Lindecken D. Technique, indication and results of sclerosing therapy in acute and recurrent bleeding from oesophageal varices in childhood. 2 Kinderchir 1979;27:38-43.

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