Which symptom indicates a need for immediate intervention in a client with Diabetic Ketoacidosis?

Kussmaul's respirations, which are characterized by deep and labored breathing, are a compensatory mechanism that occurs in response to metabolic acidosis, particularly in conditions like Diabetic Ketoacidosis (DKA). This type of respiratory pattern indicates that the body is attempting to counterbalance the acidosis by increasing the rate of carbon dioxide elimination. When a client exhibits Kussmaul's respirations, it suggests that they are experiencing significant metabolic derangement and the potential for severe outcomes if not intervened upon quickly.

The presence of this symptom is a clear indication that the client's condition may be worsening and requires immediate medical attention to prevent further complications, such as respiratory failure or a rapid progression of DKA. In contrast, increased thirst, frontal headaches, and stomach pains may point to dehydration or other symptoms related to hyperglycemia and DKA but do not signify the same immediate and severe physiological threat that Kussmaul's respirations do. Therefore, Kussmaul's respirations are the critical symptom that necessitates urgent intervention.