CLINICAL HISTORY: Santo G., a 47 year old Hispanic man with a long history of obesity and type 2 diabetes of recent onset, required daily insulin injections. His wife brought him to the emergency room early in the morning because he was confused, breathing rapidly, and having to urinate far more often than normal. "He's having one of those acid attacks," she said, "when everything gets out of balance." She further revealed that he had not been careful about his diet--- the night before he had gorged on pizza and ice cream and had consumed 8 to 10 bottles of beer, becoming so inebriated that he went to sleep without taking his insulin.

PHYSICAL EXAMINATION AND OTHER DATA: Vital signs included temperature 39 C (102.2 F), heart rate 96 beats per minute(normal 72), and blood pressure 90/60(normal 120/80). Respirations were noted to be "fast and hard," and his breath had an unusual "paint thinner or nail polish remover" odor. Santo was 5 ft 9 in. tall and weighed 285 lb. He was drowsy and confused about time and place. Lab tests revealed abnormally high blood glucose and low (acidic) blood pH. His urine was also unusually acidic and contained large amounts of glucose and ketone bodies, neither of which should normally be present. He also had high blood osmolarity (indicating increased blood solutes), low blood bicarbonates, and low blood partial pressure of CO2. His urine also had a very high specific gravity.

CLINICAL COURSE: The emergency room physician made a diagnosis of diabetic ketoacidosis and admitted Santo to the hospital. He was given insulin injections and large volumes of intravenous electrolyte solution containing bicarbonate. Further studies failed to find infection or any other underlying cause of his fever. Within 24hrs, Santo was doing much better. He was discharged on the third hospital day.

QUESTIONS:

1. Santo's blood volume is decreased and his osmolarity increased. How will these changes affect ANP, ATll, ALDOSTERONE, and ADH production?