Biomedical subjects
Cal Matsumoto
Publications and source records attributed to Cal Matsumoto.
Venous hemodynamics in living donor right lobe liver transplantation.
We evaluated the influence of portal and hepatic venous hemodynamics on the immediate and 3-month postoperative function of living donor right lobe grafts. Portal velocity was measured prospectively by ultrasound in 14 consecutive donor/recipient pairs. Velocity was converted to flow with the Moriyasu formula. Measurements were taken in donors in the operating room and in recipients at 1 hour after reperfusion and 3 months after transplant. Recipient liver function tests were measured postoperatively. Prereperfusion and postreperfusion liver biopsies were evaluated and correlated with the hemodynamic and biochemical results. There were 11 male (78.6%) and 3 female donors (mean age, 38.9 +/- 9.8 years) for 10 male (71.4%) and 4 female recipients (mean age, 49.3 +/- 14 years). The mean graft/recipient weight ratio was 1.22 +/- 0.3. The mean right portal vein pressure was 8 +/- 1.8 mm Hg in donors versus 13 +/- 4.7 mm Hg in recipients (P < .05). The mean peak flow velocity (Vmax) in the portal vein in donors was 47.6 +/- 12.8 cm/sec (normal, 44 cm/sec). One hour after graft reperfusion in the recipient, the mean portal Vmax was significantly higher at 94.7 +/- 28.4 cm/sec (P = .004), but by 3 months follow-up, mean portal Vmax had fallen to 58.8 +/- 37.8 (P = .01). Recipient portal vein Vmax highly correlated with portal flow (r = 0.7, P = .01). Increased recipient total bilirubin on postoperative day 2 correlated highly with higher recipient portal flow one hour after transplant (r = 0.6; P =.03). Portal vein velocity/flow dramatically increases after reperfusion, returning to baseline about 3 months after transplant. Evaluation of hepatic and portal venous flow is a relatively easy skill to acquire. Intraoperative ultrasound may enable the surgeon to predict graft dysfunction and possibly, may be used to implement pre-emptive therapies.
Hepatocellular carcinoma: a prime indication for living donor liver transplantation.
Cadaveric liver transplantation for hepatocellular carcinoma (HCC) is limited by donor organ availability. This report reviews our initial experience with living donor liver transplantation (LDLT) for HCC. Since August 1998, a total of 71 adults have undergone LDLT; 27 (38%) for HCC. Underlying diagnoses included hepatitis C in 17, hepatitis B in eight, cryptogenic cirrhosis in one, and primary biliary cirrhosis in one. Four patients had recurrent HCC after resection. Patients with tumors measuring 5 cm or larger received a single dose of intravenous doxorubicin intraoperatively and six cycles of doxorubicin at 3-week intervals beginning 6 weeks postoperatively. All HCC patients are followed with CT scans and alpha-fetoprotein measurements every 3 months during the first 2 years after transplant. Mean waiting time to transplant for patients with HCC was 83 days, compared to 414 (P = 0.001) days for 50 patients with HCC who were transplanted with cadaveric organs during this period. At median follow-up of 236 days, there have been four deaths due to non-tumor-related causes and one death from recurrence; recurrence has been observed in one other patient. LDLT permits expeditious transplantation in patients with early HCC, and provides access to transplantation for patients with HCC exceeding the United Network of Organ Sharing criteria for prioritization who are, in effect, barred from receiving cadaveric organs.
Hospitalized gastrointestinal bleeding and procedures after renal transplantation in the United States.
The risk of hospitalized gastrointestinal bleeding (GIB) in renal transplant recipients has not been studied in a national renal transplant population. Therefore, 42,906 renal transplant recipients in the United States Renal Data System (USRDS) from 1 July 1994 - 30 June 1998 were analyzed in an historical cohort study of hospitalizations with a primary discharge diagnosis of GIB (ICD9 Code 578.9x) using Cox regression analysis. The 1997 National Hospital Discharge Survey was used to obtain rates of GIB for the general population. Renal transplant recipients had a cumulative incidence of hospitalizations for GIB of 334 events/100,000 person-years. In 1997, compared to the general population, renal transplant recipients had an age-adjusted rate ratio for GIB of 10.69 at one year of follow-up. The strongest risk factors for GIB in Cox regression analysis were graft loss (adjusted hazard ratio, 4.28 (2.84-6.47) and African American recipients who experienced allograft rejection (AHR, 3.04, 95% CI, 1.45-6.37). GIB was associated with increased all-cause mortality (hazard ratio 1.78, 95% CI, 1.39-2.28). GIB is significantly more common in renal transplant recipients than in the general population, and the strongest risk factors are graft loss and African Americans who experience rejection.