Hyperperfusion and cardioplegia effects on myocardial high-energy phosphate distribution and energy expenditure.

This study examines the hypothesis that high-energy phosphate (HEP) compound levels in unstimulated in vivo myocardium are defined by 1) the level of perfusion and 2) non-perfusion-dependent metabolic characteristics. This hypothesis was tested by determining 1) the effects of pharmacological hyperperfusion of functioning myocardium on transmural HEP compound distribution, contractile function, and myocardial oxygen consumption rate (MVO2) as well as 2) the effect of KCl cardioplegia on transmural myocardial HEP compound distribution. Creatine phosphate (CP) and ATP were measured across the anterior left ventricular wall using spatially localized 31P-nuclear magnetic resonance (NMR).

Spectroscopy of the isolated rabbit heart: effects of perfusion with oxygenated crystalloid cardioplegia at 4 degrees C and 20 degrees C.

Factors that limit survival of explanted cardiac allografts include intracellular acidosis and loss of high energy phosphates. This study was undertaken to determine if these processes could be retarded by specific interventions during organ storage and to determine the capabilities of phosphorus-31 (31P) nuclear magnetic resonance spectroscopy to monitor these intracellular changes noninvasively. Thirty-six excised rabbit hearts were studied in six groups according to the storage temperature and conditions of their perfusion: nonperfused, aerated perfusate or oxygenated perfusate, each at 4 degrees C and 20 degrees C.

Aminoglycoside peritoneal lavage: lack of efficacy in experimental fecal peritonitis.

The utility of an adjunctive aminoglycoside lavage in the prevention of intra-abdominal abscesses utilizing an experimental rodent model was studied. Peritonitis was created in 115 rats by the intra-abdominal placement of gelatin capsules containing a barium-sulfate, human stool mixture. Four hours later, the animals were re-explored and lavaged with 30 ml/kg of sterile saline.

The role of glucose in preventing stress gastric mucosal injury.

Unlabelled: Reports from other investigators have shown the ability of pretreatment with either parenteral (glucose) or enteral (bolus Vivonex HN) nutrition to protect against stress ulcer formation, suggesting that the mechanism of protection may be substrate availability. However, these prior animal studies have used inordinately high amounts of Vivonex HN (equal to 1050 ml/hr in a human). This study compared cytoprotection afforded by pretreatment with a continuous infusion of Vivonex HN at a more clinically applicable level to that of both parenteral (ip) and enteral (po) glucose to test the above hypothesis.