N-acetylcysteine ameliorates reperfusion injury after warm hepatic ischemia

Glutathione is important in cellular defense against oxidative stress. We postulated that administration of N-acetylcysteine (NAC), a glutathione precursor, might help maintain or replenish hepatic glutathione stores, thereby reducing reperfusion injury in liver grafts after warm ischemia. Eighteen pigs were subjected to 2 hr of warm hepatic ischemia and divided into a control group (group A, n = 6), a preischemia treatment group (group B, n = 6: NAC, 150 mg/kg, continuous i.v. infusion 1 hr before ischemia), and a postischemia treatment group (group C, n = 6: NAC, 150 mg/kg continuous i.v., begun 20 min before reperfusion and continued for 1 hr). At initiation of laparotomy, we measured hepatic levels of reduced glutathione (GSH), its oxidized form (GSSG), ATP, aspartate aminotransferase (AST), and lactate dehydrogenase (LDH). Before reperfusion, after 2 hr of warm ischemia, GSH, GSSG, and ATP were measured. One hour after reperfusion, we measured GSH, GSSG, ATP, AST, and LDH. Bile output was recorded every 10 min. Postoperfusion AST and LDH were significantly lower in both treatment groups than in controls. In group B, hepatic glutathione was maintained at significantly higher levels than in controls, even after ischemia (P < 0.05). In group C, although hepatic GSH levels fell until reperfusion, after administration of NAC, hepatic GSH reached the level of the preischemia treatment group. In both treatment groups, GSH 1 hr after reperfusion was significantly higher than in the controls (P < 0.01): regeneration of glutathione was seen in all 6 animals in group C, compared with 2/6 in group B and none in the control group. ATP recovery, bile output, and survival were all better in the treatment groups than in the control group. Pretreatment with NAC helps maintain hepatic glutathione during warm ischemia; given after ischemia, NAC is effective in replenishing depleted glutathione stores. Adjunctive use of NAC was associated with improved glutathione homeostasis, improved bile output and ATP regeneration, and increased survival.

Severe or multiple rejection episodes are associated with early recurrence of hepatitis C after orthotopic liver transplantation

Recurrent hepatitis C causes significant morbidity after liver transplantation. Because immunosuppression is associated with enhanced viral replication, we postulated that clinical recurrence of the disease may be associated with augmented immunosuppression for rejection. In 96 patients with hepatitis C who received liver transplants, we recorded the interval from transplantation to recurrence, the episodes of steroid-resistant rejection (SRR) requiring OKT3, the number of rejection episodes, and the use of OKT3 induction. Recurrence was diagnosed based on elevated transaminases and characteristic histology. Hepatitis C recurred in 43 of 96 patients. Fifteen of 21 patients (71.4%) who previously had SRR had recurrence, versus 28 of 75 patients (37.3%) who either had no SRR (72 patients) or had it after recurrence was diagnosed (3 patients) (P < .01). Mean time to recurrence was 127 +/- 31 days in the 15 patients who had had SRR versus 246 +/- 42 days in the other 28 patients (P = .02). Recurrence and number of rejection episodes were clearly associated: 6 of 33 patients (18.2%) with no rejection had recurrence (P < .05), versus 11 of 26 patients (42.3%) with one rejection episode (P < .05) and 26 of 37 (70.2%) with more than 1 episode (P < .05). OKT3 induction was used in 15 patients; 9 of 15 patients had recurrence (ns) at 337 +/- 95 days. Of 72 patients who initially received triple immunosuppression, 30 patients had recurrence at 186 +/- 25 days (P = .05). Nine patients received primary FK506; 4 had recurrence at 68 +/- 14 days.(ABSTRACT TRUNCATED AT 250 WORDS)

Preservation injury in clinical liver transplantation: incidence and effect on rejection and survival

The distribution of the severity of preservation injury (PI), its association with acute early rejection, and its effect on graft and patient survival were examined in 151 patients transplanted between 9/88 and 12/91. PI was graded into mild, moderate and severe using prothrombin time (PT) on the 2nd POD and peak AST and ALT levels of the first 3 days after transplant. Of the 151 patients, 104 (68.8%) had minimal, 24 (15.9%) had moderate, and 23 (15.3%) had severe PI. The rate of early rejection, within 21 days after transplant, (54.8% vs 54.2% vs 52.2%) and its timing (10.0 +/- 0.5 vs 8.8 +/- 0.8 vs 8.9 +/- 1.4 days) as well as the incidence of steroid-resistant rejection (21.4% vs 33% vs 30%) did not differ significantly among groups. Graft survival was significantly lower in the severe PI group than among patients with minimal PI at 3 months and 24 months (65.2% vs 86.2%; p < 0.05 and 58.3% vs 82.7%; p < 0.05, respectively). Patient survival at 3 and 24 months was similar among the groups (91.1% vs. 95.8% vs 86.9% and 81.9% vs 91.1% vs. 74.3%). We conclude that the cellular damage associated with preservation injury does not predispose to development of acute rejection.

Flushing with autologous blood improves intraoperative hemodynamic stability and early graft function in clinical hepatic transplantation

Hemodynamic instability and hyperkalemia are common after reperfusion and may cause ischemic damage on the hepatic allograft. Two techniques for flushing hepatic grafts before reperfusion were studied to evaluate their effects on intraoperative hemodynamic and metabolic status and on early graft function in 83 consecutive adult hepatic transplantations. In the first 41 patients (group 1), the hepatic grafts were rinsed with 500 milliliters of lactated Ringer's solution (LR). In the subsequent 42 patients (group 2), in addition to LR rinse, the first 500 milliliters of portal blood to flush and reperfuse the liver were drained through the cannula inserted into the donor vena cava before unclamping the vena cava. After reperfusion, the mean arterial pressure decreased 30 +/- 4 percent in group 1 versus 17 +/- 2 percent in group 2 (p < 0.02), and serum K+ increased by 1.9 +/- 0.2 in group 1 versus 0.8 +/- 0.2 milliequivalents per liter in group 2 (p < 0.01). Hyperkalemic cardiac arrest was only seen in two patients in group 1. The K+ concentration in the first 100 milliliters of discarded blood was found to be 40 +/- 2 milliequivalents per liter. The 500 milliliters of discarded blood contained 8.3 +/- 0.4 milliequivalents, which was correlated with graft liver weight (p < 0.001). Early graft function, as measured by serum glutamic-oxaloacetic transaminase, serum glutamic pyruvic transaminase, total bilirubin and prothrombin time on postoperative day No. 2, was significantly better in group 2 than in group 1 (p < 0.05). The six-month graft and patient survival rates in group 1 were 66 and 75 percent, versus 90 and 95 percent in group 2 (p < 0.01 and p < 0.02, respectively). Further flushing with 500 milliliters of autologous portal blood resulted in smaller intraoperative shifts in serum K+, greater hemodynamic stability, better graft function and improved graft and patient survival.

Adoptive cellular therapy of human breast and colorectal tumor targets using ex vivo activated memory T lymphocytes with potentiation by cis-diamminedichloroplatinum(II)

Autolymphocyte therapy (ALT) is adoptive cellular therapy of cancer using ex vivo activation of autologous peripheral blood lymphocytes (PBL). Memory T cells are the principal effector population in ALT, with in vivo activity in patients with metastatic renal cell carcinoma (RCC) and melanoma, and ex vivo cytotoxicity against autologous tumor targets. However, the noncytolytic lymphocyte portion of ex vivo-activated memory T cells (ALT cells) may also contribute as antitumor effectors. Pretreatment of murine and human tumor cells ex vivo with chemotherapeutic agents can enhance their susceptibility to antitumor lymphocytes ex vivo and in vivo. To determine whether cis-diamminedichloroplatinum(II) (DDP) could enhance ex vivo antitumor effects of ALT cells by immunomodulation, human breast and colorectal carcinoma target cells were derived from both primary and metastatic surgical specimens and incubated in complete medium (CM) with DDP or in CM alone (control group). Viability of each group was confirmed by trypan blue-dye exclusion test. ALT cells were prepared from autologous PBL at surgery. Primary and metastatic tumor cells from each group were used as targets for ALT cells and levels of interferon-gamma (IFN-gamma) release were measured as a determination of antitumor effect and recognition. Primary tumor target cells incubated in DDP showed enhanced antitumor effects and recognition by autologous ALT cells, as measured by the IFN-gamma assay compared to non-DDP-treated controls. Metastatic autologous tumor target cells demonstrated less IFN-gamma release than did the primary targets, although this was enhanced by pre-treating metastatic tumor targets with DDP. ALT cells demonstrated minimal IFN-gamma release when incubated with allogeneic tumor targets. These data suggest that autotumor recognition of metastatic tumor targets is comparable to that of primary lesions following ex vivo pretreatment of metastatic cells with nonlethal doses of certain chemotherapeutic agents. DDP may somehow alter the physical properties of target cells, rendering them susceptible to immune-mediated attack and the combination of ALT and DDP may lead to increased therapeutic efficacy in patients with metastatic breast and colon cancer.

Obviation of prereperfusion rinsing and decrease in preservation/reperfusion injury in liver transplantation by portal blood flushing

Liver allografts are traditionally rinsed with cold lactated Ringer's (LR) prereperfusion to clear K(+)-rich preservation solution from the hepatic vasculature. LR has been shown, however, to be injurious to the graft. By restoring portal blood flow without rinsing and discarding the initial blood traversing the liver (PB flush), we sought to eliminate rinsing without inducing hyperkalemia. Between August 1988 and December 1992, 481 OLTx were performed in 412 pts. Four rinsing methods were used sequentially: group 1 (157 pts)--low-flow-rate cold LR rinse (500 ml, 100 ml/min via standard i.v. tubing at 100 cm H2O [LFLR]) during lower caval anastomosis; Group 2 (120 pts)--LFLR as in group 1, at reperfusion, 500 ml PB flush via IVC catheter; group 3 (66 pts)--high-flow-rate LR rinse (500 ml, 1 L/min using large-bore tubing with 100 cm H2O rinsing pressure [HFLR]), PB flush as in group 2; Group 4 (62 pts)--no LR rinse; PB flush as in groups 2 and 3. Poor early graft function (PEGF) was defined as peak ALT or AST > 2500 U or PT > 16 sec (on POD 2); PEGF causing re-OLTx or death within 14 days was called primary nonfunction (PNF). Group 1 and Group 3 had high PEGF rates. Group 4 had significantly less PEGF than Group 1, with a trend toward a significant difference from Group 3. In Group 1, 3 pts. had intraoperative hyperkalemic cardiac arrest; this did not occur when PB flush was performed. PB flush without prior rinsing optimizes graft function without risk of hyperkalemia. LR rinse, alone or followed by PB flush, is unnecessary and may be deleterious.

Neurologic complications of orthotopic liver transplantation

Neurologic complications are frequent after liver transplantation and are the cause of significant morbidity and mortality. A substantial proportion of the neurologic complications encountered after transplant is iatrogenic--the consequence of the harsh therapeutic interventions required to maintain function of the transplanted liver. The preoperative condition of the patient is also a major determinant of the incidence and impact of neurologic complications, as is the occurrence of poor early graft function or of repeated rejection episodes that require augmented immunosuppression. By recognizing the early signs of drug-related neurotoxicity, it is often possible to preempt the development of more severe trouble. Careful perioperative fluid management, specifically related to sodium and glucose levels, may reduce the risk of CPM. As effective treatment modalities have emerged, an aggressive approach to the diagnosis of central nervous system infection has assumed increased importance. With persistent attention to the details of basic patient care as well as to the specific neurologic diagnosis, and with a commitment to intensive rehabilitation therapy, the large majority of patients who suffer neurologic complications after transplant can ultimately return to a productive life.

Prolonged preservation in University of Wisconsin solution associated with hepatic artery thrombosis after orthotopic liver transplantation

Hepatic artery thrombosis (HAT) after liver transplantation (LTx) usually mandates retransplantation. Prolonged preservation with Eurocollins solution has been associated with HAT. We reviewed our experience with 359 LTx patients to identify risk factors for HAT. All grafts were preserved in University of Wisconsin solution. HAT developed in 12 patients (3%) within 50 days. Seven patients were asymptomatic; four presented with biliary sepsis and 1 with poor graft function. Two patients had suffered acute rejection; another 2 had severe preservation injury. Technical problems accounted for 4 cases; in the remaining 8, no etiology was found. Diagnosis was at a mean 14.7 days after LTx. One patient maintains normal graft function 3 years after LTx without intervention. Eight underwent re-LTx, 3 of whom died. Routine surveillance via duplex enabled early diagnosis and revascularization in 3 patients; in all 3, no biliary complications occurred between 6 and 20 months. Overall graft and patient survival after HAT were 33.3% and 75%, respectively. Cold ischemic time (CIT) averaged 813 min in patients with HAT and 669 min in those without HAT (P < .05). HAT occurred in 7/165 patients with CIT > 12 hr, and in 3/234 patients with CIT < 12 hr (P = 0.0699). By avoiding CIT > 12 hr, we have recently avoided HAT in 78 consecutive patients. We conclude that CIT > 12 hr may increase the risk of HAT. When HAT is diagnosed before biliary sepsis develops, flow can often be restored and retransplantation averted.