PARALLEL DIALYSIS NORMALIZES SERUM CHEMISTRIES DURING VENOVENOUS PERFUSION INDUCED HYPERTHERMIA

Whole-body hyperthermia is currently under investigation as a method t o treat systemic malignancies; however, available techniques induce a derangement in serum and urine chemistries. This study was done to det ermine whether veno-venous perfusion induced hyperthermia (vv-PISH) th at incorporated a parallel dialysis system to control blood chemistrie s would eliminate these heat induced derangements. Adult female Yorksh ire swine were divided into perfusion only (group P, n = 6, 62.8 +/- 2 .5 kg), and perfusion with dialysis (group PD, n = 6, 63.8 +/- 4.3 kg) . In both groups, hyperthermia was induced with a computer assisted ju gular-to-femoral venovenous heat exchange/perfusion system primed with a balanced electrolyte solution, operating at 30 ml/min(-1)/kg(-1) wh ich used a thermal gradient induced by blood heated to a maximum of 48 degrees C and a perfusate-to-blood temperature gradient <10 degrees C during heating. The target core temperature was 43 degrees C for 120 min as measured by the average of the rectal, bladder, esophageal, bil ateral tympanic, and pulmonary artery temperatures. Including ramp-up and cool down, the total perfusion interval was 263 +/- 29 min in grou p P and 240 +/- 18 min in group PD (ns). Serum and urine chemistry val ues expressed as the mean value +/- SEM were compared before and after hyperthermia treatment. Variables include blood urea nitrogen, creati nine, sodium, potassium, chloride, calcium, magnesium, phosphorus, glu cose, total protein, albumin, alkaline phosphatase (ALKP), creatinine kinase, aspartate aminotransferase, alanine aminotransferase (ALT), la ctate dehydrogenase (LDH), plasma free hemoglobin, urine specific grav ity, pH and urine creatinine. All variables remained within normal ran ges for the PD group. In the P group, the following final values were outside the normal range: (normal range) creatinine 2.1 +/- 1 (0.4-1.4 ) mg/dl, Ca2+ 5.1 +/- 1 (6-13) mg/dl, Mg2+ .8 +/- 0.1 (1.2-10) mg/dl, ALKP 134 +/- 6 (34-122) U/L, ALT 69 +/- 3 (9-51) U/L, and LDH 1291 +/- 237 (300-600) U/L. We conclude that the significant changes in serum and urine chemistries associated with vv-PISH are normalized with the use of a parallel dialysis system and may decrease the incidence of el ectrolyte associated complications.