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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Administration, Oral, Aged, Antioxidants, Ascorbic Acid, Humans, Middle Aged, Multiple Organ Failure, Postoperative Complications, Postoperative Period, Preoperative Care, Surgical Procedures, Operative.
user
Does single preoperative oral application of ascorbic acid affect postoperative plasma levels of ascorbic acid? Context: A decrease in ascorbic acid (AA) plasma concentration is well known during the postoperative period and postulated to be caused by increased radical scavenging activity in response to surgical trauma. This often affects postoperative patients and is associated with multiple organ failure. Therefore, substitution of AA could potentially decrease the risk of postoperative complications. This study examines the effect of preoperative oral administration of 1,000 mg AA on the postoperative AA plasma concentration. 54 patients were randomly split into two groups; patients in group 1 received no AA preoperatively while group 2 received oral AA (1,000 mg). Plasma samples were obtained preoperatively and on the first postoperative day for AA analysis (HPLC). In both groups the AA concentration was normal preoperatively and reduced postoperatively.
assistant
A preoperative substitution of 1,000 mg AA is not sufficient to prevent postoperative lowered plasma concentration. Final Decision: no