GASTRIC INTRAMURAL PH AS INDICATOR OF EARLY ALLOGRAFT VIABILITY IN ORTHOTOPIC LIVER-TRANSPLANTATION

The determination of the viability of OLT grafts has relied upon metab olic tests of the liver, which take several hours to evaluate and ther efore are only conclusive in most patients well into the postoperative period. Earlier diagnosis of graft failure or nonfunction would allow intraoperative reassessment of surgical technique and, in the case of graft failure, earlier planning for retransplantation. Since gastroin testinal mucosal ischemia is one of the earliest manifestations of imp aired core tissue in the critically ill, a tonometric nasogastric tube (Tonomitor) was used in our patients to measure intramucosal gastric pH (pHi) during the preanhepatic (stage I), anhepatic (stage II), and neohepatic (stage III) phases of OLT in 35 patients as an indicator of graft liver function and viability. Based on the results of the pHi m easurement 30 min after reperfusion during stage III, patients were di vided into 2 groups using a pHi of 7.30 as the dividing point. Patient s with a pHi equal or higher than 7.30 were assigned to group 1 (n=24) and patients with a pHi lower than 7.30 were assigned to group 2 (n=1 1). The pHi in group 1 patients averaged 7.37+/-0.5 30 min after reper fusion and throughout surgery. The pHi in group 2 patients was lower t han that of the group 1 patients 30 min after reperfusion, 7.23+/-0.04 (P<0.001). The pHi in 10 group 2 patients returned to normal within 3 hr after reperfusion and the pHi values for these patients were not s ignificantly different from those of group 1 at 3 hr after reperfusion . The pHi in 1 group 2 patient remained lower than 7.30 and never retu rned to normal; this patient underwent retransplantation the following day. Utilizing the tonometric nasogastric tube to sample intramucosal pH allowed early detection of graft function and intermittent trendin g of pHi in patients with questionable graft function during the opera tive period. It also provided a means of assessing graft function inde pendent of enzymatic criteria, which provide little information in the early phase of transplantation.