Anesthesia of the pig poses great problems for experimental animal-based research and particularly in shock research. In this study, five mechanically ventilated domestic pigs were given long-term anesthesia with a combination of ketamine plus pentobarbital. Circulatory parameters were recorded every 2 h via an arterial catheter placed in the right common carotid artery, a Swan-Gans thermodilution catheter (7F), that was placed in the pulmonary artery of the right middle-lobe in a wedge position through the external jugular vein, and another catheter in the internal jugular vein for measuring central venous pressure. Moreover, body weight, blood gases, pH, blood cells, electrolytes and serum enzymes were measured. Further serum traits as total protein and glucose and pathological alterations in different organs were recorded. The animals were observed for a period of 96 h and then killed painlessly. It was shown that pigs can survive 96-h anesthesia with the combination of ketamine and pentobarbital. Optimum, carefully controlled anesthesia did not impair the integrity of the regulatory mechanisms of circulation.