ACUTE METABOLIC AND ENDOCRINE EFFECTS OF INDUCED HYPOTHERMIA IN HEMORRHAGIC-SHOCK - AN EXPERIMENTAL-STUDY IN THE PIG

Background: Hypothermia is considered harmful in trauma patients, In s urgery, hypothermia is occasionally used to reduce metabolism and prot ect the brain. Recent studies in animals have also shown protective ef fects of hypothermia in hemorrhagic shock. The aim of this study was t o evaluate the metabolic and endocrine effects of induced hypothermia in hemorrhagic shock. Methods: Half of the individually calculated blo od volume was removed from 17 anesthetized piglets. They were then ran domized to normothermia or hypothermia and followed for 4 hours after hemorrhage. Results: In the hypothermic pigs, arterial Po-2 increased from 10.3 +/- 0.7 to 16.4 +/- 0.9 kPa, but it remained unchanged in th e normothermic group. The serum levels of potassium increased from 3.9 +/- 0.2 to 5.0 +/- 0.2 mmol/L in the normothermic group. In the hypot hermic pigs, the potassium levels temporarily decreased from 3.8 +/- 0 .1 to 3.0 +/- 0.1 mmol/L but then returned to baseline levels. The lev els of serum catecholamines surged in both groups during hemorrhage, T hey remained elevated in normothermic pigs but declined in the hypothe rmic group. Conclusion: In porcine hemorrhagic shock, induced hypother mia increases arterial oxygen tension and stabilizes serum levels of p otassium and catecholamines.