OBSERVATIONS ON WATER AND ELECTROLYTE CHANGES IN SKELETAL MUSCLE DURING MAJOR SURGERY

Samples were cut from rectus abdominis in ten patients at the beginning and end of large-scale vascular operations. Ten slices from each biopsy specimen were each analyzed for fat, water, Na, K, and Cl. Two biopsy specimens were taken at the end of operation: from an area of muscle that had been under a retractor throughout operation and from an area that had not. Blood was sampled at the beginning and end of operation and analyzed for water, Na, K, Cl, and osmolality. In all patients rectus abdominis tissue gained water, Na, and Cl, and lost K during operation. Detailed examination of findings suggested that muscle cells gain Na, Cl, and water; and that by the end of the operation a balanced state still does not obtain. On the average there is neither gain nor loss of extracellular fluid. If a sufficient mass of tissue shows these changes, there will be a general shrinkage in ECF; otherwise there will not. Consequences of tissue changes and their implications for the patient and his treatment are discussed. It is suggested that cellular changes underlie retention of Na, Cl, and water, and loss of K after operation and injury. © 1969.