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Annals of Surgery | 1993

Surgical techniques and innovations in living related liver transplantation.

Koichi Tanaka; Shinji Uemoto; Yukihiko Tokunaga; Shiro Fujita; Kaoru Sano; Takashi Nishizawa; Hisashi Sawada; Isao Shirahase; Hong Jin Kim; Yoshio Yamaoka; Kazue Ozawa

The authors successfully performed a series of 33 living related liver transplantations (LRLT) on children (15 males and 18 females, ranging from 7 months to 15 years of age) from June 1990 to May 1992, with the informed consent of their parents and the approval of the Ethics Committee of Kyoto University. Before operation, six of the children required intensive care, another 14 were hospitalized, and 13 were homebound. Donors (12 paternal and 21 maternal) were selected solely from the parents of the recipients on the basis of ABO blood group and graft/recipient size matching determined by computed tomography scanning. Procurement of graft was performed using ultrasonic aspirator and bipolar electrocautery without blood vessel clamping and without graft manipulation. All donors subsequently had normal liver function and returned to normal life. The left lateral segment (16 cases), left lobe (16 cases), or right lobe (one case) were used as grafts. The partial liver graft was transplanted into the recipient who underwent total hepatectomy with preservation of the inferior vena cava using a vascular side clamp. Twenty-seven of 33 recipients are alive and well with the original graft and have normal liver function. The patient survival rate was 89% (24/27) in elective cases and 50% (3/6) in emergent cases. The other six recipients had functioning grafts but died of extrahepatic complications. Complications of the graft were minimal in all cases. Hepatic vein stenosis, which occurred three times in two cases, was successfully treated by balloon dilatation. In cases with sclerotic portal vein, the authors anastomosed the portal vein of the graft to the confluence of the splenic vein and the superior mesenteric vein without a vascular graft, after experiencing a case of vascular graft thrombosis. After hepatic artery thrombosis occurred in one of the initial seven recipients whose arterial anastomosis was done with surgical loupe, microsurgery was introduced for hepatic artery reconstruction. There has been no occurrence of thrombosis since then. The current results with LRLT suggested that the meticulous management of surgical factors at each stage of the LRLT procedure is crucial for successful outcome. Living related liver transplantation is a promising option for resolving the graft shortage in pediatric liver transplantation and may be regarded as an independent modality to supplement cadaver donation.


American Journal of Surgery | 1994

Living related liver transplantation in children

Koichi Tanaka; Shinji Uemoto; Yukihiko Tokunaga; Shiro Fujita; Kaoru Sano; Eiji Yamamoto; Motoki Sugano; Masaaki Awane; Yoshio Yamaoka; Kaoru Kumada; Kazue Ozawa

We reviewed 37 living related liver transplantations (LRLT) performed by our department during the last 27 months on children with end-stage liver disease. The patients were 15 boys and 22 girls aged 7 months to 15 years with biliary atresia (27), cryptogenic cirrhosis (3), Budd-Chiari syndrome (2), progressive intrahepatic cholestasis (2), protoporphyria (1), Wilsons disease (1), and fulminant hepatitis (1). The donors were 14 fathers and 23 mothers. Grafts were made from the left lateral segment (19), left lateral segment with partial S4 (11), left lobe (6), and right lobe (1). After graft harvesting all donors resumed normal liver function and normal life. The recipient underwent total hepatectomy with preservation of the inferior vena cava. FK506 and low-dose steroids were used for immunosuppression. The survival rate was 90% (27/30) in elective cases and 57% (4/7) in emergency cases. Six recipients had functioning grafts but died of extrahepatic complications. Hepatic vein stenosis occurred in 3 cases at 3 months after LRLT and was successfully treated by balloon dilatation. Portal vein stenosis occurred in 1 case at 8 months after LRLT and was also safely dilated. We incurred no hepatic artery thrombosis after introducing microsurgery techniques. Among 12 viral, 5 bacterial, and 3 fungal postoperative infections, 1 Candida pneumonia and 1 EBV-associated lymphoma were lethal. Three patients with ABO-blood group compatible grafts and one with an incompatible graft developed acute rejection, which was controlled in evey case by steroid bolus and/or increasing the dose of FK506. There were no definite episodes of rejection in ABO-identical cases. Children with moderate growth retardation (> or = -1.5 SD of normal growth) caught up in growth soon after LRLT, but those with severe retardation (<-1.5 SD) were slow to attain age-normal height. Appropriate timing, meticulous surgical procedures, and comprehensive management of complications are crucial for successful outcome with LRLT. LRLT is a promising option for alleviating the shortage of livers for pediatric transplantation and may be regarded as an independent modality to supplement cadaver donation.


Transplantation | 1993

The Effects Of Cold Preservation On Steatotic Graft Viability In Rat Liver Transplantation

Michihiro Hayashi; Yukihiko Tokunaga; Takuji Fujita; Koichi Tanaka; Yoshio Yamaoka; Kazue Ozawa

Clinical experience suggests that grafts obtained from steatotic livers result in primary nonfunction more frequently than those from nonsteatotic livers. To date, however, only a few studies have been done to verify the accuracy of this observation. To investigate the effects of cold preservation on steatotic liver viability, liver grafts obtained from rats fed with a choline-deficient diet were transplanted after periods of cold preservation. Recipient survival rates with normal liver grafts were 8/8 (100%) and those with steatotic liver grafts were 7/8 (88%) (P>0.05) after 1-hr preservation with UW solution. After 9-hr preservation, however, these rates decreased significantly to 0/8 (0%) with steatotic grafts (P<0.01), but were not significantly decreased with normal grafts. LDH levels in the effluent at the time of transplantation were 133 IU/L (1-hr) and 512 IU/L (9-hr) in normal livers, but in steatotic livers these were elevated to 598 and 3141 IU/L, respectively (P<0.01). Recovery rates of hepatic blood flow measured by laser Doppler flowmeter after revascularization were 99% (1-hr) and 96% (9-hr) in normal grafts, but in steatotic grafts they were 98% (1-hr) and 63% (9-hr, P<0.01). In addition, the oxidative phosphorylation ability of liver mitochondria obtained from steatotic grafts was decreased significantly after cold preservation. The present results suggest that steatotic liver grafts are prone to lose their viability more easily than normal liver grafts after prolonged periods of cold preservation due to a combination of causes.


Transplantation | 1993

Experience with FK506 in living-related liver transplantation.

Shinji Uemoto; Koichi Tanaka; Kazuo Honda; Yukihiko Tokunaga; Kaoru Sano; Hironori Katoh; Eiji Yamamoto; Yasutsugu Takada; Kazue Ozawa

The new immunosuppressive agent FK506 was used with steroids to treat 22 pediatric patients who received living-related partial liver transplantation. Seventeen recipients survived and 5 died between one and 16 months after transplantation. Three of the 5 patients who died had required intensive care preoperatively. Autopsy findings showed no evidence of rejection. There was no episode of rejection that required retransplantation in any of the patients. Liver allograft dysfunction, which was suspected to be a rejection response, was encountered in 2 recipients with ABO-nonidentical but compatible grafts. However, their clinical and biochemical findings were ameliorated upon steroid pulse therapy or upon augmented FK506 administration without additional potent immunosuppressive agents. Steroid treatment has been discontinued in all surviving patients at 1–9 months after transplantation. Infectious complications encountered in 9 patients included 2 bacterial, 5 viral, and 2 fungal infections. One recipient died of fungal pneumonia. Abnormal increase of serum creatinine level was confined to the complicated patients. Hypertension was a temporary adverse reaction in the early postoperative period, and only one patient needed an antihypertensive drug at 2 months after transplantation. Acute pancreatitis with hyperamylasemia was observed in one patient who was treated successfully with reduction of FK506 administration. Tremor was observed in 8 patients, itching in 4, insomnia in 2, and vomiting in one. Hirsutism, gingival hypertrophy, and lymphoma were not observed. FK506 was highly effective in living-related partial liver transplantation not only in terms of immunosuppressive potential but also because it produced fewer adverse effects.


Journal of The American College of Surgeons | 1998

Density of Helicobacter pylori Infection in Patients with Peptic Ulcer Perforation

Yukihiko Tokunaga; Koichiro Hata; Junmei Ryo; Akihiro Kitaoka; Atsuo Tokuka; Kiyosi Ohsumi

BACKGROUND A lack of change in prevalence of severe ulcer complications requiring emergency operation has been reported, despite the common use of histamine-2 (H2)-receptor antagonists and proton pump inhibitors. This may be attributable to use of ulcerogenic drugs or Helicobacter pylori (HP) infection, or both. In this study, HP infection was evaluated semiquantitatively in patients with peptic ulcer who required surgery, and the severity of histologic change was investigated. METHODS We reviewed a total of 113 consecutive patients (98 men and 15 women) operated on for perforation, hemorrhage, or stenosis of gastroduodenal ulcer between January 1986 and December 1995. Detection of HP was carried out by immunohistochemical staining. We graded the density of HP infection according to the number of individual HP bacteria counted in a highly magnified visual field (x 1,000 of light microscopy). The grade of HP infection was defined as follows: (0) = 0; (1+) = 1-9; (2+) = 10-29; (3+) = 30-99; (4+) > or = 100. The severity of gastritis was evaluated by histologic examination using the criteria of Rauws. RESULTS Although the number of operations for gastroduodenal ulcer declined significantly, the rate of emergency operation for gastroduodenal ulcer increased from 60% to 90%, with the result that the frequency of operations for perforation or bleeding remained virtually constant and that for stenosis significantly decreased. HP infection was more prevalent in perforated ulcer (92%) than hemorrhagic ulcer (55%) or stenotic ulcer (45%). The grades of HP infection were 3.0 +/- 0.14 (mean +/- SEM) in perforated ulcer, 2.3 +/- 0.34 in hemorrhagic ulcer, and 2.5 +/- 0.22 in stenotic ulcer. Perforated ulcer was associated with significantly more severe HP infection and gastritis changes than hemorrhagic ulcer or stenotic ulcer. CONCLUSIONS This study indicates that patients with perforated ulcer were infected with HP more severely than those with hemorrhagic ulcer or stenotic ulcer at the time of surgery. A close relationship was observed between the perforated ulcer and the density of HP infection determined semiquantitatively using immunohistochemical stain.


Transplantation | 1994

LIVING RELATED LIVER TRANSPLANTATION ACROSS ABO BLOOD GROUPS

Akira Tanaka; Koichi Tanaka; Toshiyuki Kitai; Nobuharu Yanabu; Atsuo Tokuka; Bunpei Sato; Shigeto Mori; Takuya Inomoto; Hisashi Shinohara; Shinji Uemoto; Yukihiko Tokunaga; Yukihiro Inomata; Yoshio Yamaoka

We performed 13 pediatric liver transplants from ABO-incompatible living related maternal or paternal donors using a combination of preoperative removal of isohemagglutinin and postoperative immunosuppressive therapy with FK506 and prophylactic OKT3. Tissue near-infrared spectroscopy was applied to evaluate hemodynamics using the hemoglobin of red cells in the sinusoids as an index. The data obtained indicated that the preoperative removal of isohemagglutinin prevented hyperacute humoral rejection with hemorrhagic infiltration in the sinusoids in 10 successful cases. The incidence of acute rejection was not significantly different among ABO-identical, -compatible, and -incompatible groups. The estimated 1-year survival rate of the ABO-incompatible group was 77%.


European Journal of Gastroenterology & Hepatology | 2000

Hepatic undifferentiated (embryonal) sarcoma in an adult: a case report and review of the literature.

Yukihiko Tokunaga; Jummei Ryo; Toshitaka Hoppou; Akihiro Kitaoka; Atsuo Tokuka; Kiyosi Osumi; Tomoyuki Tanaka

Undifferentiated (embryonal) sarcoma of the liver (USL) is a rare malignant tumour with a poor prognosis. The absence of specific symptoms, the rapid tumour growth, the normality of the common tumour markers, and the consequential delay in the diagnosis often result in significant enlargement of the


Transplantation | 1987

Fluorometric study for the noninvasive determination of cellular viability in perfused rat liver

Yukihiko Tokunaga; Nobuhiro Ozaki; Shigetaro Wakashiro; Iwao Ikai; Taisuke Morimoto; Yasuyuki Shimahara; Yasuo Kamiyama; Yoshio Yamaoka; Kazue Ozawa; Yuzo Nakase

Pyridine nucleotide fluorescence in perfused rat liver for the noninvasive determination of donor graft viability was investigated in relation to other metabolic indices, such as NAD concentration, adenine nucleotides, and mitochondrial phosphorylative activity. The amplitude between oxidation and reduction levels (R×A) in fluorometric trace, and the slope or the velocity of the trace curve from oxidation to reduction (R×V) were determined by the measurement of fluorescence from NAD(P)H, using a new fluorometric device, R×A and R×V decreased proportionally to the duration of preservation period (6, 12, 24, 48 hr) in simple cold storage. Other values of hepatic cell viability, such as total adenine nucleotides, energy charge, and mitochondrial phosphorylation rate, were simultaneously measured and also decreased proportionally to the duration of preservation period. There were close positive correlations between the percentage of R×A and NAD concentration (r=0.724, p <0.01), between the percentage of R×A and total adenine nucleotides (r=0.887, p <0.01), between the percentage of R×V and energy charge (r=0.715, p <0.01), and between the percentage of R×V and phosphorylation rate/cytochrome a(+a3) (r=0.837, p <0.01). These results suggest that this fluorometric method can provide an accurate noninvasive evaluation of donor graft viability—and, unlike the present indices of energy metabolism, it may be applied to evaluate the primary nonfunctioning graft prior to transplantation.


Surgery Today | 1998

Spontaneous perforation of the rectum with possible stercoral etiology: Report of a case and review of the literature

Yukihiko Tokunaga; Koichiro Hata; Ryota Nishitai; Junichi Kaganoi; Hirokazu Nanbu; Kiyosi Ohsumi

Stercoral perforation of the colon or rectum is a rare cause of acute abdomen, with fewer than 70 cases documented in the literature. We report herein the case of a 60-year-old man who presented with anuria and epigastric pain with physical signs of peritonitis. An abdominal X-ray showed bilateral subphrenic free air accumulation, and an emergency laparotomy subsequently revealed perforation of the rectum, suggestive of a stercoral cause, which was treated by simple closure after debridement. Following an uneventful postoperative course, he was discharged from the hospital 3 weeks after his operation and is now doing well without having suffered any further gastrointestinal problems. The clinical features, diagnosis, and treatment of the disease are reviewed following the presentation of this case. Surgeons should be aware of the possibility of this fatal disease, despite its rare incidence. Furthermore, it is important to recognize the condition at an early stage because it has a significantly high mortality if not treated early. Conversely, the surgical outcome is satisfactory provided surgery is performed in due time.


Transplant International | 1994

Living‐related liver transplantation for fulminant hepatic failure in children

Koichi Tanaka; Shinji Uemoto; Yukihiro Inomata; Yukihiko Tokunaga; Mikiko Ueda; Atsuo Tokka; Bunpei Sato; Yoshio Yamaoka

Abstract Liver transplantation is increasingly accepted as a choice of treatment for fulminant hepatic failure (FHF) since it has been proved to significantly improve the survival rate in these patients compared with other therapeutic modalities. We have successfully performed a total of 76 living related liver transplantations (LRLT) three of which were for FHF. The first case was an 11‐year‐old boy with FHF due to an unidentified cause. He had required plasmapheresis a total of 24 times and haemofiltration to save his life before LRLT. He was transplanted with a left lobe (420 g) graft, calculated as 1.05 % of his weight (40 kg). He recovered hepatic function uneventfully and was discharged from hospital after 7 weeks. The second case was a 13‐year‐old girl who developed FHF with grade III encephalopathy due to acute Wilsons disease, and was referred to us. She underwent LRLT with a left lobe graft (440 g), estimated as 0.95% of her weight (47 kg), which functioned well after surgery. The third case was a 13‐year‐old girl with grade II encephalopathy due to acute Wilsons disease. She was 27% obese with a body weight of 58 kg. She underwent LRLT with ABO blood group incompatibility with a left lobe (352 g), estimated as 0.80% of her weight (modified 44 kg). She was discharged with sensorimotor neuropathy due to vitamin B deficiency. The present results suggest that LRLT is feasible for FHF both clinically and ethically, and that a partial liver graft weighing around 1 % of the recipients weight can maintain the recipients life. We limit the diagnostic indication for LRLT to chronic liver disease, since an urgent situation may affect a voluntary decision for the patients parents to donate the partial liver. However, LRLT is thought to be an acceptable choice of treatment provided it h requested by the patient and family. Furthermore, it is a potential option for resolving the graft shortage in paediatric liver transplantation, being independent of cadaver donor availability.

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Kazue Ozawa

Shiga University of Medical Science

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Paul Nakazato

California Pacific Medical Center

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