Monosegmental liver transplantation

Large-for-size syndrome prophylaxis in infant liver recipients with low body mass

Transplantation of the left lateral section (LLS) of the liver is now an established practice for treating advanced diffuse and unresectable focal liver diseases in children, with variants of the LLS primarily used in infants. However, the surgical challenge of matching the size of an adult donor's graft to the volume of a child's abdomen remains significant. This review explores historical developments, various approaches to measuring the required functional liver mass, and techniques to prevent complications associated with large-for-size grafts in infants.

"Reduced Size Liver Grafts in Pediatric Liver Transplantation; Technical Considerations"

Liver transplantation (LT) has become a vital treatment option for children with end-stage liver disease. Left lateral segment (LLS) grafts are particularly common in split and living donor LT for pediatric patients. However, challenges arise in small infants receiving LLS grafts, primarily due to graft-size mismatches, resulting in "large-for-size" grafts. To overcome this issue, the practice of further reducing grafts from the LLS to diminish graft thickness has been explored. Currently, the indication for reducing the thickness of LLS grafts includes recipients with a body weight (BW) under 5.0 kg, neonates with acute liver failure, or those with metabolic liver disease. At the National Center for Child Health and Development in Tokyo, Japan, among 131 recipients of reduced-size LLS grafts, a remarkable 15-year graft survival rate of 89.9% has been achieved in small infants. This success indicates that with experience and refinement of the technique, there's a trend towards improved graft survival in recipients with reduced-thickness LLS grafts. This advancement underscores the importance of BW-appropriate methods in graft selection to ensure exceptional outcomes in vulnerable pediatric patients in need of LT. These techniques' ongoing development and refinement are crucial in enhancing the survival rates and overall outcomes for these young patients.

Optimal graft size in pediatric living donor liver transplantation: How are children different from adults?

BACKGROUND

Pediatric liver transplantation is an established treatment for end-stage liver disease in children. However, it is still posing relevant challenges, such as optimizing the graft selection according to the recipient size. Unlike adults, small children tolerate large-for-size grafts and insufficient graft volume might represent an issue in adolescents when graft size is disproportionate.

METHODS

Graft-size matching strategies over time were examined in pediatric liver transplantation. This review traces the measures/principles put in place to prevent large-for-size or small-for-size grafts in small children to adolescents with a literature review and an analysis of the data issued from the National Center for Child Health and Development, Tokyo, Japan.

RESULTS

Reduced left lateral segment (LLS; Couinaud's segment II and III) was widely applicable for small children less than 5 kg with metabolic liver disease or acute liver failure. There was significantly worse graft survival if the actual graft-to-recipient weight ratio (GRWR) was less than 1.5% in the adolescent with LLS graft due to the small-for-size graft. Children, particularly adolescents, may then require larger GRWR than adults to prevent small-for-size syndrome. The suggested ideal graft selections in pediatric LDLT are: reduced LLS, recipient body weight (BW) < 5.0 kg; LLS, 5.0 kg ≤ BW < 25 kg; left lobe (Couinaud's segment II, III, IV with middle hepatic vein), 25 kg ≤ BW < 50 kg; right lobe (Couinaud's segment V, VI, VII, VIII without middle hepatic vein), 50 kg ≤ BW. Children, particularly adolescents, may then require larger GRWR than adults to prevent small-for-size syndrome.

CONCLUSION

Age-appropriate and BW-appropriate strategies of graft selection are crucial to secure an excellent outcome in pediatric living donor liver transplantation.

Hyperreduced left lateral living donor liver transplant in a 4.5 kg child-A first in Africa

BACKGROUND

Supply-demand mismatch in solid organ transplantation is particularly pronounced in small children. For liver transplantation, advanced surgical techniques for reducing deceased and living donor grafts allow access to life-saving transplantation. Living donor left lateral segment liver grafts have been successfully transplanted in small children in our center since 2013, the only program providing this service in Sub-Saharan Africa. This type of partial graft remains too large for children below 6 kg body weight and generally requires reduction.

METHODS

A left lateral segment graft was reduced in situ from a directed, altruistic living donor to yield a hyperreduced left lateral segment graft.

RESULTS

The donor was discharged after 6 days without complications. The recipient suffered no technical surgical complications except for an infected cut-surface biloma and biliary anastomotic stricture and remains well 9 months post-transplant.

CONCLUSIONS

We report the first known case in Africa of a hyperreduced left lateral segment, ABO incompatible, living donor liver transplant in a 4,5 kg child with pediatric acute liver failure (PALF).

Monosegment Liver Allografts for Liver Transplantation in Infants Weighing Less Than 6 kg: An Initial Indian Experience

BACKGROUND

Living donor liver transplantation in small infants is a significant challenge. Liver allografts from adults may be large in size. This is accompanied by problems of graft perfusion, dysfunction, and the inability to achieve primary closure of the abdomen. Monosegment grafts are a way to address these issues.

METHODS

Two recipients in our cohort weighed less then 6 kg. The prospective left lateral segments from their donors were large for size. Therefore, monosegment 2 liver grafts were harvested. Data regarding the preoperative, intraoperative, and postoperative events in the donor and the recipient were recorded.

RESULTS

We were able to achieve significant reduction in the sizes of the grafts harvested. The donors underwent surgery and hospital stay uneventfully. The recipients had normal graft perfusion and no graft dysfunction, and we could achieve primary abdominal closure. One recipient had self-limiting bile leak postoperatively.

CONCLUSIONS

Monosegment 2 liver allografts are safe and effective for use in living donor liver transplantation in small infants weighing less than 6 kg.

Dorsal approach plus branch patch technique is the preferred method for liver transplanting small babies with monosegmental grafts

PURPOSE

When living donor liver transplantation (LDLT) is performed on small infant patients, the incidence of hepatic artery complications (HACs) is high. Here, we present a retrospective analysis that focuses on our surgical procedure for hepatic arterial reconstruction and the outcomes of monosegmental LDLT.

METHODS

Of the 275 patients who underwent LDLT between May 2001 and December 2015, 13 patients (4.7 %) underwent monosegmental LDLT. Hepatic artery reconstruction was performed under a microscope. The size discrepancy between the graft and the recipient's abdominal cavity was defined as the graft to recipient distance ratio (GRDR) between the left hepatic vein and the portal vein (PV) bifurcation on a preoperative computed tomography scan. HACs were defined as hepatic arterial hypoperfusion.

RESULTS

Recipient hepatic arteries were selected for the branch patch technique in five cases (38.5 %), and the diameter was 2.2 ± 0.6 mm. The anastomotic approaches selected were the dorsal position of the PV in seven cases (53.8 %) and the ventral position in six, and the GRDRs were 2.8 ± 0.4 and 1.9 ± 0.5, respectively (p = 0.012). The incidence rate of HACs caused by external factors, such as compression or inflammation around the anastomotic site, was significantly higher in monosegmental than in non-monosegmental graft recipients (15.4 vs. 1.1 %, p < 0.001).

CONCLUSION

Although monosegmental graft recipients experienced HACs caused by external factors around the anastomotic field, hepatic arterial reconstruction could be safely performed. Important components of successful hepatic arterial reconstructions include the employment of the branch patch technique and the selection of the dorsal approach.

Large-for-size liver transplant: a single-center experience

OBJECTIVES

The ideal ratio between liver transplant graft mass and recipient body weight is unknown, but the graft probably must weigh 0.8% to 2.0% recipient weight. When this ratio > 4%, there may be problems due to large-for-size transplant, especially in recipients < 10 kg. This condition is caused by discrepancy between the small abdominal cavity and large graft and is characterized by decreased blood supply to the liver graft and graft dysfunction. We evaluated our experience with large-for-size grafts.

MATERIALS AND METHODS

We retrospectively evaluated 377 orthotopic liver transplants that were performed from 2001-2014 in our center. We included 188 pediatric transplants in our study.

RESULTS

There were 58 patients < 10 kg who had living-donor living transplant with graft-to-bodyweight ratio > 4%. In 2 patients, the abdomen was closed with a Bogota bag. In 5 patients, reoperation was performed due to vascular problems and abdominal hypertension, and the abdomen was closed with a Bogota bag. All Bogota bags were closed in 2 weeks. After closing the fascia, 10 patients had vascular problems that were diagnosed in the operating room by Doppler ultrasonography, and only the skin was closed without fascia closure. No graft loss occurred due to large-for-size transplant. There were 8 patients who died early after transplant (sepsis, 6 patients; brain death, 2 patients). There was no major donor morbidity or donor mortality.

CONCLUSIONS

Large-for-size graft may cause abdominal compartment syndrome due to the small size of the recipient abdominal cavity, size discrepancies in vascular caliber, insufficient portal circulation, and disturbance of tissue oxygenation. Abdominal closure with a Bogota bag in these patients is safe and effective to avoid abdominal compartment syndrome. Early diagnosis by ultrasonography in the operating room after fascia closure and repeated ultrasonography at the clinic may help avoid graft loss.

Selection of living donor liver grafts for patients weighing 6kg or less

In the field of pediatric living donor liver transplantation (LDLT), physicians sometimes must reduce the volume of left lateral segment (LLS) grafts to prevent large-for-size syndrome. There are 2 established methods for decreasing the size of an LLS graft: the use of a segment 2 (S2) monosegment graft and the use of a reduced LLS graft. However, no procedure for selecting the proper graft type has been established. In this study, we conducted a retrospective investigation of LDLT and examined the strategy of graft selection for patients weighing ≤6 kg. LDLT was conducted 225 times between May 2001 and December 2012, and 15 of the procedures were performed in patients weighing ≤6 kg. We selected S2 monosegment grafts and reduced LLS grafts if the preoperative computed tomography (CT)-volumetry value of the LLS graft was >5% and 4% to 5% of the graft/recipient weight ratio, respectively. We used LLS grafts in 7 recipients, S2 monosegment grafts in 4 recipients, reduced S2 monosegment grafts in 3 recipients, and a reduced LLS graft in 1 recipient. The reduction rate of S2 monosegment grafts for use as LLS grafts was 48.3%. The overall recipient and graft survival rates were both 93.3%, and 1 patient died of a brain hemorrhage. Major surgical complications included hepatic artery thrombosis in 2 recipients, bilioenteric anastomotic strictures in 2 recipients, and portal vein thrombosis in 1 recipient. In conclusion, our graft selection strategy based on preoperative CT-volumetry is highly useful in patients weighing ≤6 kg. S2 monosegment grafts are effective and safe in very small infants particularly neonates.

Pediatric liver transplantation using reduced and hyper-reduced left lateral segment grafts: a 10-year single-center experience

Few studies have examined the long-term outcomes and prognostic factors associated with pediatric living living-donor liver transplantation (LDLT) using reduced and hyper-reduced left lateral segment grafts. We conducted a retrospective, single-center assessment of the outcomes of this procedure, as well as clinical factors that influenced graft and patient survival. Between September 2000 and December 2009, 49 patients (median age: 7 months, weight: 5.45 kg) underwent LDLT using reduced (partial left lateral segment; n = 5, monosegment; n = 26), or hyper-reduced (reduced monosegment grafts; n = 18) left lateral segment grafts. In all cases, the estimated graft-to-recipient body weight ratio of the left lateral segment was more than 4%, as assessed by preoperative computed tomography volumetry, and therefore further reduction was required. A hepatic artery thrombosis occurred in two patients (4.1%). Portal venous complications occurred in eight patients (16.3%). The overall patient survival rate at 1, 3 and 10 years after LDLT were 83.7%, 81.4% and 78.9%, respectively. Multivariate analysis revealed that recipient age of less than 2 months and warm ischemic time of more than 40 min affected patient survival. Pediatric LDLT using reduced and hyper-reduced left lateral segment grafts appears to be a feasible option with acceptable graft survival and vascular complication rates.

Liver graft volumetric changes after living donor liver transplantation with segment 2 graft for small infants

LT for small infants weighing <5 kg with liver failure might require innovative techniques for size reduction and transplantation of small grafts to avoid large-for-size graft, but little is known about post-transplant graft volumetric changes. Five of 172 children who underwent LDLT received monosegment or reduced monosegment grafts using a modified Couinaud's segment II (S2) graft for LDLT. Serial CT was used to evaluate the changes in the GV and other factors before LDLT and one and three months after LDLT. The shape of these grafts was classified into an OL type and an LL type. The GV increased in all patients one month after LDLT, whereas the GV decreased three months after LDLT in OL in comparison with one month after LDLT. The GRWR of the OL type has tended to decrease at three months, whereas the LL type showed a continuous increase with time, but finally they had adapted graft size for their body size. In conclusion, the volume of S2 grafts after LDLT had unique changes toward the ideal volume for the child weight when they received the appropriate liver volume.

Transplantation with hyper-reduced liver grafts in children under 10 kg of weight

BACKGROUND

We had previously described a left lateral segment hyper-reduction technique capable of sizing the graft according to the volume of the abdominal cavity of the recipient.

AIM

The purpose of our study was to evaluate our 14-year live-donor liver transplantation experience with in situ graft hyper-reduction in children under 10 kg of weight.

PATIENTS AND METHODS

Between January 1997 and May 2011, we performed 881 liver transplants. Two hundred and seventy-seven (n = 277) involved pediatric recipients, of which 102 (37 %) were from live donors. Thirty-five (n = 35) patients under 10 kg of weight underwent hyper-reduced living donor liver transplants. There were 21 females (60 %) and 14 males (40 %), with a median age of 12 months (range 3-23) and a median weight of 7.7 kg (range 5.6-10).

RESULTS

Median operative time was 350 min (range 180-510). Median cold ischemia time was 180 min (range 60-300). Twenty-six (n = 26) patients required intraoperative transfusion of blood products. There were 49 postoperative complications involving 26 patients (74 % morbidity rate). One-, 3-, and 5-year survival rates were 87, 79, and 74 %, respectively. Twenty-eight patients are currently alive.

CONCLUSIONS

Hyper-reduced grafts provide an alternative approach for low-weight pediatric recipients. The relatively high immediate postoperative morbidity could be related to the complexity of these patients.

Implications for the usage of the left lateral liver graft for infants ≤10 kg, irrespective of a large-for-size situation--are monosegmental grafts redundant?

Organ donor shortage for infant liver transplant recipients has lead to an increase in splitting and living donation. For cases in which even transplantation of the left lateral graft (Couinaud's segments II + III) results in a "large for size situation" with an estimated graft body weight ratio (GBWR) of >4%, monosegmental liver transplantation was developed. This, however, bears complications because of greater parenchymal surface and suboptimal vascular flow. We exclusively use the left lateral graft from living donors or split grafts. Temporary abdominal closure is attempted in cases of increased pressure. We report of 41 pediatric transplants in 38 children ≤10 kg. Within this group, there were 23 cases with a GBWR of ≥4, and 15 cases with a GBWR <4. There was no statistical difference in vascular or biliary complications. Despite a more frequent rate of temporary abdominal closure, we did not find a higher rate of intra-abdominal infections. Overall, patient and graft survival was excellent in both groups (one death, three re-transplants). We noticed, however, that the ventro-dorsal diameter of the graft appears to be more relevant to potential graft necrosis than the actual graft size. In conclusion, the usage of monosegmental grafts seems unnecessary if transplantation of left lateral grafts is performed by an experienced multidisciplinary team, and temporary abdominal closure is favored in cases of increased abdominal pressure.

Living donor liver transplantation for neonates using segment 2 monosubsegment graft

The prognosis of liver transplantation for neonates with fulminant hepatic failure (FHF) continues to be extremely poor, especially in patients whose body weight is less than 3 kg. To address this problem, we have developed a safe living donor liver transplantation (LDLT) modality for neonates. We performed LDLTs with segment 2 monosubsegment (S2) grafts for three neonatal FHF. The recipient age and body weight at LDLT were 13-27 days, 2.59-2.84 kg, respectively. S2 or reduced S2 grafts (93-98 g) obtained from their fathers were implanted using temporary portacaval shunt. The recipient portal vein was reconstructed at a more distal site, such as the umbilical portion, to have the graft liver move freely during hepatic artery (HA) reconstruction. The recipient operation time and bleeding were 11 h 58 min-15 h 27 min and 200-395 mL, respectively. The graft-to-recipient weight ratio was 3.3-3.8% and primary abdominal wall closure was possible in all cases. Although hepatic artery thrombosis occurred in one case, all cases survived with normal growth. Emergency LDLT with S2 grafts weighing less than 100 g can save neonates with FHF whose body weight is less than 3 kg. This LDLT modality using S2 grafts could become a new option for neonates and very small infants requiring LT.

Reduction of left-lateral segment from living donors for liver transplantation in infants weighing less than 7 kg: technical aspects and outcome

LLS reduction has been frequently used in infants weighing <7 kg. Twenty recipients weighing <7 kg at the time of LDLT, median age 11.0 months and body weight 5.6 kg, were treated with an RLLS (n = 12) or LLS (n = 8) graft. Absolute indication of size reduction was that the estimated GRWR was >4.0%. Even if the preoperative GRWR was <4.0%, the RLLS graft was considered to ensure a size match. A flatfish-type LLS was preferred to a blowfish-type to make an RLLS graft for such a small infantile population. The RLLS recipients had significantly more flatfish-type grafts, while the LLS recipients had more blowfish-type grafts. Primary full-layer wound closure could be performed successfully in all LLS recipients, while in the RLLS group, two patients were forced to have partial skin closure. There were no graft losses related to graft compression. Reducing an LLS is a useful procedure to promote the comfortable accommodation of the graft in an infant weighing <7 kg. Flatfish-type LLS allowed more flexibility to make the suitable volume.

Obstacles to the establishment of liver transplantation in Australia

A quarter of a century ago the commencement of liver transplantation in Australia was controversial and surrounded by medical and political intrigue. The medical opposition to its establishment was led by the Medical Journal of Australia with scathing condemnation, especially with regard to the transplantation of children. Interstate political rivalry, most prominently between the Queensland and Victorian and Federal Governments was at the forefront and was a fertile field for media attention. Despite all the obstacles, liver transplantation came to fruition and the results achieved have more than justified its introduction and continued performance. In addition, contributions from Australia have had a significant impact around the world.

The reduced left lateral segment in pediatric liver transplantation: an alternative to the monosegment graft

Tailoring graft size to small paediatric recipients is a challenge. We have developed a reduced left lateral segment as an alternative to monosegment transplantation for small size recipients. Since November 2000, 89 children have been transplanted with 100 deceased donor liver grafts in our unit. Our median patient and graft survival is 89% and 88% respectively. Four of these cases were performed using a new technique of creating a small donor graft by reducing the left lateral segment. The median weight of the reduced liver graft was 264 g (range: 165-390 g). The median blood transfusion requirement was 101 mL/kg body weight (range 69-167 mL/kg). The median values of peak ALT were 1473 IU/L, INR 2.2 and bilirubin 293 micromol/L in the first two wk following surgery. One neonatal recipient died five days after transplantation from a massive intracranial haemorrhage despite satisfactory graft function. Another recipient with excellent graft function died 10 months later from primary pulmonary hypertension and secondary cardiac failure. Hepatic artery thrombosis occurred in one patient with successful revascularization but he was retransplanted three months later for chronic rejection. No biliary or venous outflow complications occurred in this group. This technique of reduced left lateral segment liver transplantation is an alternative to the monosegment graft and allows small recipients to be successfully transplanted with few technical complications related to graft preparation.

Living donor liver transplantation for acute liver failure in infants: the impact of unknown etiology

Infants with ALF occasionally have the most urgent need for a liver transplant. In urgent situations for liver transplantation, LDLT has been advocated. Between July 1995 and April 2004, medical records of 15 infants undergoing LDLT for ALF of unknown etiology were reviewed and their outcomes were compared with infants undergoing LDLT for other liver diseases. They received LLS (n = 9), MS (n = 3), and RMS (n = 3) grafts. Eight technical complications occurred, with a similar incidence for LDLT and the other liver diseases. On the other hand, the liver biopsies after LDLT showed a significantly higher incidence of ACR with centrilobular injuries. Ten patients died after primary LDLT because of refractory rejection (n = 6), rotavirus infection (n = 2), chronic rejection (n = 1), and surgical complications (n = 1). With a median follow-up of 7.0 months, five-yr graft and patient survival rates were 17.8% and 26.7%, respectively. In conclusion, the outcome of LDLT for ALF in infants, especially cases with unknown etiology, was unsatisfactory and refractory rejection often led to liver failure. From our observation the centrilobular changes were characteristics of ACR in infantile LDLT for cryptogenic ALF.

Living donor liver transplantation for children in Brazil weighing less than 10 kilograms

Infants with end-stage liver disease represent a treatment challenge. Living donor liver transplantation (LDLT) is the only option for timely liver transplantation in many areas of the world, adding to the technical difficulties of the procedure. Factors that affect morbidity and mortality can now be determined, which opens a new era for improvement. We have accumulated an 11-year experience with LDLT for children weighing<10 kg. From October 1995 to October 2006, a total of 222 LDLT in patients<18 years of age were performed; 129 primary LDLT and 7 retransplants (4 LDLT and 3 deceased donor grafts) were performed in 129 infants weighing<10 kg. Forty-seven patients received grafts with graft-to-recipient weight ratio (GRWR) of >4%. Two patients received monosegmental grafts, and 2 patients underwent delayed abdominal wall closure. Portal vein thrombosis occurred in 5.4% of the patients, hepatic artery thrombosis in 3.1%, and both in 1.5%. Among several variables studied, only the bilirubin level at the time of transplantation was associated with increased risk of death (P=0.009). Grafts with GRWR>4% had no negative effect on patient survival. There were 7 retransplants, and 4 patients received a second parental LDLT. Patient survival rates at 1, 3, and 10 years after transplantation were 88.8%, 84.7%, and 82% for all children, and 87.5%, 84.9%, and 84.9% for infants weighing<10 kg. LDLT has results comparable to other modalities of liver transplantation in infants. Monosegment grafts were rarely required in this series, although they may be necessary in patients with lower body weight.

Living donor liver transplantation with reduced monosegments for neonates and small infants

BACKGROUND

In pediatric living donor liver transplantation, left lateral segment or monosegmental graft is used to overcome size discrepancies between adult donors and pediatric recipients. For neonates and extremely small infants, however, problems related to large-for-size graft are sometimes encountered even when using such grafts. The reduced monosegmental graft, in which the caudal part of the monosegmental graft is resected, has been introduced to address this problem.

METHODS

Of 566 children who underwent transplant between June 1990 and September 2004, reduced monosegment living donor liver transplants were used for nine patients (median age, 144 days; median weight, 4.1 kg). This technique was used for infants with estimated graft-to-recipient weight ratio (GRWR) > or =4.0% when using the left lateral segment.

RESULTS

Graft and patient survival was 66.7%. GRWR was reduced from 7.45+/-2.70% to 3.39+/-0.89% using this modification. Transaminase levels at days 1 and 2 after transplantation were significantly higher in reduced monosegmental transplantation than in left lateral segmental transplantation. Hepatic artery thrombosis and portal vein thrombosis were observed in one case each.

CONCLUSION

Reduced monosegmental living donor liver transplantation represents a feasible option for neonates and extremely small infants with liver failure.

Liver transplantation with monosegments. Technical aspects and outcome: a meta-analysis

The shortage of organ donors for low-weight liver transplant recipients, especially small children, has led to the development of new surgical techniques to increase the donor pool. Almost all of these techniques use the left lateral segment (Couinaud's segments II and III), but even this graft could be too large for children under 10 kg, and further reduction could be necessary. Few articles address the issue of monosegmental liver transplantation. Available articles are with small sample sizes or even case reports, which makes it difficult to draw conclusions about indication and outcome for monosegmental grafts. A search of the MEDLINE databases using the terms "Liver Transplantation" and "Monosegmental" or "Monosegments" limited to title or abstract with publication in the English language was conducted. The data from each study were selected and analyzed, regarding donor status (living or cadaveric), donor weight, surgical techniques used in left lateral further reduction, recipient indication for liver transplantation, age and recipient weight, graft-to-recipient body weight ratio, segment utilized, type of abdominal closure, postoperative complications, and survival. Seven publications were identified from 1995 to 2004 and fulfilled the criteria. A total of 27 pediatric patients who received a monosegment transplant were identified, median age 211 days (range, 27 to 454 days) and median weight 4.6 kg (range, 2.45 to 7.4 kg). Segment III was utilized in 21 (78%) and segment II in 6 (22%). Patient survival was 85.2%. In conclusion, monosegment liver transplantation appears to be a satisfactory option for infants weighing less than 10 kg who require a liver transplant.

Liver transplantation with monosegment from a living donor

The shortage of organ donors for low-weight liver transplant recipients, especially for small children, has led to the development of new surgical techniques to increase the donor pool. Almost all of these techniques use the left lateral segment (Couinaud's segments II and III), but even this graft could be too large for children under 10 kg. We report here the case of an 8-month-old boy, weighing 6.1 kg, who received a monosegmental graft (segment III) from his grandmother weighing 68 kg. The graft was reduced at the donor surgery, before clamping of the vessels. The donor was discharged on the fourth post-operative day; the recipient had an uneventful post-operative period and was discharged after 22 days.

N/A

N/A

Living-donor liver transplantation with monosegments

BACKGROUND

Living-donor liver transplantation is now an established technique to treat children with end-stage liver disease. Implantation of left-lateral segment grafts can be a problem in small infants because of a large-for-size graft. We report 10 cases of transplantation using monosegment grafts from living donors.

METHOD

Of 506 children transplanted between June 1990 and June 2002, 10 patients (median age 196 days, median weight 5.9 kg) received monosegment living-donor liver transplants. The indication for using this technique was infants with an estimated graft-to-recipient weight ratio of over 4.0%.

RESULTS

Graft and patient survival was 80.0%. There were no differences in donor operation time and blood loss between monosegmentectomy and left-lateral segmentectomy (n=281). Monosegmental transplantation had a high incidence of vascular complications (20.0%).

CONCLUSION

Monosegmental living- donor liver transplantation is a feasible option with satisfactory graft survival in small babies with liver failure.

Liver transplantation in neonates

Orthotopic liver transplantation (OLT) has evolved over the past two decades to become the standard of care for end-stage liver disease in infants and children. Technical advances, particularly the use of technical variant allografts, have permitted extension of OLT into a much younger and smaller population than previously possible. Major centers around the world now routinely perform OLT in infants with survival success equivalent to that in older children and adults. We are beginning to see a small population of school-aged children who were infant OLT recipients. The further extension of OLT into neonates is more recent, with only a few pediatric centers reporting survival success. Very little is known about this frontier of transplantation. Our intent is to provide an overview of neonatal OLT using all available data and our experience in the field.

Monosegmental living-donor liver transplantation for infantile hepatic hemangioendothelioma

Infantile hepatic hemangioendothelioma (IHHE) is a rare vascular tumor that presents before the age of 6 months. The patients with IHHE suffer from high-output congestive heart failure caused by major arteriovenous fisutulas in the liver, which leads to respiratory compromise and results in a high mortality rate despite medical treatments. A case of 4-month-old baby with liver failure caused by IHHE is reported. The baby received an urgent liver transplantation from a living donor. A monosegmental graft was used to mitigate graft-to- recipient size mismatching. The surgical procedure of monosegmental living donor liver transplantation also is discussed.

Size reduction of small bowels from adult cadaveric donors to alleviate the scarcity of pediatric size-matched organs: an anatomical and feasibility study

BACKGROUND

Small bowel transplantation in children weighing less than 10 kg is hindered by the lack of size-matched donors. The ability to create reduced size small bowel grafts from adult cadaveric donors suitable for use in young children has been studied.

METHODS

Volumetric assessment of computed tomography scans were used to evaluate abdominal cavity and small bowel volumes in children. Small bowels were retrieved from adult cadaveric donors and reduced in size.

RESULTS

Computed tomography studies of the abdominal cavity showed that the mean volume available for a small bowel graft was 260 ml in children less than 5 kg (n = 5) and 460 ml in children weighing 5-10 kg (n = 5). Fifteen small bowels were successfully reduced to provide an ileal graft of one meter while keeping the whole length of the superior mesenteric artery and vein after their dissection in the proximal part of the mesentery. The mean volume of the grafts created was 270 ml in seven thin patients (body mass index [BMI] <25), 390 ml in five preobese patients (25< BMI<30), and 490 ml in three obese patients (BMI>30). Mesenteric transillumination in thin donors allowed safe dissection and complete hemostasis. No diameter reduction was required. Technical modifications permitted the creation of two grafts, one ileal and the other jejunal from a single donor. Volumetric and surgical data show that implantation of up to two meters of ileum from a thin adult weighing up to 80 kg is feasible in children weighing less than 10 kg.

CONCLUSION

Size reduction of adult cadaveric small bowels can provide suitable grafts for children of less than 10 kg and could expand the potential pool of donors for these patients.

Partial left lateral segment transplant from a living donor

A shortage of liver donors for low-weight transplant recipients has prompted the development of procedures for liver-reduction, split-liver, and living related donor transplantations. For pediatric recipients weighing less than 10 kg, the left lateral segment is often still too large. We describe the procedure of monosegmental transplantation using segment II after segment III was resected in situ from a living related donor. Successful monosegmental transplantation is technically feasible and is a valid alternative to be considered for cases of size discrepancy between the recipient's volume and the donor's left lateral segment.

Liver transplantation with monosegments

BACKGROUND

Shortage of size-matched pediatric donors led to the development of surgical techniques to reduce or split livers and thus increase the potential pool of donors. Despite this, neonatal transplantation remains a problem because of the small size of the recipients. Further reduction of the left lateral segment is possible to provide a single segment graft (segment III). We report our experience of transplanting 6 babies using this technique.

METHODS

Of 310 children transplanted in our center between October 1989 and March 1998, 6 patients, 2 male and 4 female, median age 37.5 days (range 5 to 92 days), median weight 3.45 kg (range 2.45 to 5.46 kg) were transplanted with a monosegment. The cause of liver failure was neonatal hemochromatosis in 4, retransplantation for hepatic artery thrombosis in 1, and hepatitis B in one. The donor liver was reduced or split to a left lateral segment. Segment II was then resected and discarded before transplantation.

RESULTS

Overall, graft and patient survival is 83.3%. Five patients are alive with good graft function at a mean follow-up of 30.4 months (range 8 to 82 months). One child who was transplanted for hepatic artery thrombosis died from sepsis and multiorgan failure 48 hrs after transplant. None of the survivors had vascular or biliary complications.

CONCLUSIONS

Monosegment liver transplantation with segment III appears to be a satisfactory option for treating small babies with liver failure.

Biliary complications in pediatric living related liver transplantation

BACKGROUND

The goal of this study was to evaluate cause and outcome of biliary complications occurring after pediatric living related liver transplantation (LRLT).

METHODS

A database of 205 pediatric patients (71 male and 134 female) undergoing 208 LRLT from June 1990 to April 1996 was reviewed.

RESULTS

The overall incidence of bile duct complications was 13.9% (29 patients). There were 19 bile leaks, 7 anastomotic strictures, 8 intrahepatic biliary complications, and the bile duct was ligated inadvertently in 2 cases. Logistic regression analysis revealed hepatic artery thrombosis, ABO incompatible transplantation, intrapulmonary shunting in recipients, mode of artery reconstruction, and cytomegalovirus infection were all significant risk factors for biliary complications.

CONCLUSIONS

Avoidance of ABO incompatible transplantation where possible, routine use of microvascular techniques for hepatic artery reconstruction to minimize the risk of artery thrombosis, earlier transplantation for patients with intrapulmonary shunt, and prophylaxis against cytomegalovirus infection should all reduce the rate of biliary complications after LRLT in pediatric recipients.

Hepatic transplantation in children under 3 months of age: a single centre's experience

Liver transplantation in neonates represents a major medical and technical challenge particularly in babies weighing less than 5 kg. The authors report the experience of 10 liver transplants in 9 babies (6 boys and 3 girls), mean age, 6 weeks (range, 2 to 11); median weight, 3.7 kg (range, 2.4 to 5). All had fulminant hepatic failure caused by neonatal haemochromatosis (n = 3), non-A non-B hepatitis (n = 3), total parenteral nutrition induced (n = 1), hepatitis B (n = 1), and hepatic haemangio-endothelioma (n = 1). One child underwent retransplantation for hepatic artery thrombosis. Immunosuppression was by Cyclosporine A-based triple therapy in all cases. All received a reduced size graft consisting of left lobe (n = 1), left lateral segment (n = 6) and monosegment III (n = 3). In nine cases the donor hepatic artery was anastomosed to an iliac artery conduit from the infrarenal aorta, and a Roux loop was used for bile duct reconstruction. Primary abdominal wound closure was possible in six patients, skin closure alone in one, and a silastic patch was used in three. Complications included infection (n = 5), bowel perforation (n = 2), diaphragmatic perforation (n = 2), bile leak (n = 1), hepatic artery thrombosis (n = 1), and portal vein thrombosis (n = 1). None of the babies experienced acute rejection. Currently five of the nine recipients are alive with good graft function at a mean follow-up of 22 months (range, 5 to 58). Of the four deaths, two were related to infection (one in combination with portal vein thrombosis), one to multiorgan failure and fluid overload, and one to early graft dysfunction and sepsis after undergoing retransplantation for hepatic artery thrombosis. From our experience liver transplantation offers a promising option for the treatment of severe liver disease in children less than 3 months old.

Monosegmental liver transplantation from an adult to an infant

A shortage of small pediatric organ donors has led to the development of reduced size liver transplantation in children. However, the discrepancy between donor and recipient weight can limit the use of this procedure despite transplantation of the left lobe only. Monosegmental liver transplantation using segment III only was recently described. We report here the case of an 11 month old, 6.9 kg boy who received another monosegmental graft (segment II) from a 78 kg donor on an urgent basis. Because of the lack of parenchymal landmarks between segments II and III, sterile methylene blue solution was injected into the portal vein of segment III: parenchyma of this segment colored immediately and was resected accordingly. Three and a half years later, the growth, development, and nutrition of this child were normal. This procedure seems to be helpful when the left lobe of the graft is obviously too large.