Dry Dwayne — Diabetes Insipidus
Liters of pale urine, Na⁺ ↑, specific gravity < 1.005
Dwayne cannot hold on to water. It runs straight through him — pale as tap water, liter after liter — while the salt left behind concentrates in his blood.
Dwayne loses ADH after a head injury and cannot concentrate urine. He puts out liters of dilute urine, gets desperately thirsty and his sodium climbs. Replace fluids, give desmopressin, and watch for the opposite problem — water intoxication.
Read Dry Dwayne's full story →The story arc
The setup
A traumatic brain injury bruises the pituitary; ADH output falls within days.
The turn
He drinks constantly and still feels parched. Urine output hits 400 mL/hr and looks like water.
The crisis
Sodium 158, blood pressure 88/54, heart rate 122, and he becomes too drowsy to keep drinking.
The save
Hypotonic fluids replace the deficit and desmopressin restores ADH — then output, weight and sodium are watched for over-correction.
NCLEX study section — Diabetes Insipidus
What this chapter is testing: the recognition cues, the numbers and the priority action.
Study section: Endocrine & Metabolic
Take this chapter into practice questions on the same topic.