Now that we have an understanding of how and why ketone bodies are produced during DKA, what are the maternal consequences resulting from excessive ketogenesis? In general, ketone bodies are considered to be moderately strong acids. In response to the fall in pH in most body fluids created by an accumulation of these acids, the body reacts physiologically to correct the resultant metabolic acidosis. The respiratory rate and depth increase (Kussmaul respirations) in an attempt to blow off carbon dioxide, initiating a corrective trend toward compensatory respiratory alkalosis. Serum bicarbonate levels decline, and as a result, the anion gap becomes abnormally elevated. In addition to increasing fatty acid production, poor glucose utilization results in severe hyperglycemia. Untreated hyperglycemia leads to marked glycosuria, initiating a significant osmotic diuresis. As a result, dehydration, electrolyte depletion, and, if left untreated, cardiac failure and death may follow.
A vicious cycle is created by an increase in dehydration-mediated serum hyperosmolarity and catabolism, propagated by Kussmaul respiration, leading to a further production of glucose counter-regulatory hormones, lipolysis, and subsequent hyperketonemia. An algorithm for this clinical pathophysiologic response is presented in Fig. 11-2.