A patient with a history of type 1 diabetes and an eating disorder is found unconscious. In the emergency department, the following lab values are obtained: Glucose: 648 mg/dL pH: 88 P CO : 20 mm Hg a 2 P O : 95 mm Hg a 2 HCO ¯: undetectable Anion gap: >31 Na+: 127 mEq/L K+: 5 mEq/L Creatinine: 8 mg/dL After the patient’s airway and ventilation have been established, the next priority for this patient is:

Correct Answer: A

Rationale: The correct answer is A: administration of a 1-L normal saline fluid bolus. In this scenario, the patient is likely experiencing diabetic ketoacidosis (DKA) due to the extremely high glucose levels, low bicarbonate, and anion gap metabolic acidosis. The priority is to correct the dehydration and electrolyte imbalances through fluid resuscitation with normal saline to improve perfusion and reverse the metabolic derangements. Options B, C, and D do not address the immediate need for volume resuscitation and correction of dehydration. Administering insulin or potassium without first addressing the fluid deficit could lead to further complications. Sodium bicarbonate is not recommended in DKA as it can worsen acidosis and has not been shown to improve outcomes.

Correct Answer: D

Rationale: The correct answer is D: “Recovery is possible, but it may take several months.” This response is the best because acute kidney injury can be reversible with appropriate management, and recovery may take time. It is important to provide hope and encouragement to the patient. A: “Unfortunately, kidney injury is not reversible; it is permanent.” - This is incorrect as acute kidney injury can be reversible with timely intervention and proper treatment. B: “Kidney function usually returns within 2 weeks.” - This is incorrect because the recovery timeline varies for each individual and can take longer than 2 weeks. C: “You will know for sure if you start urinating a lot all at once.” - This is incorrect as increased urine output may not always indicate complete recovery from acute kidney injury.

Correct Answer: C

Rationale: The correct answer is C: intrarenal disease, probably acute tubular necrosis. The presence of coarse, muddy brown granular casts and hematuria in the urinalysis indicates damage to the renal tubules, which is characteristic of acute tubular necrosis. This condition is a type of intrarenal disease where there is direct damage to the kidney tubules, leading to decreased urinary output and symptoms like malaise and fatigue. Prerenal and postrenal conditions do not typically present with granular casts and hematuria, making choices A and B incorrect. Urinary tract infection is also unlikely to cause the specific findings seen in this case, ruling out choice D. Therefore, choice C is the most appropriate based on the urinalysis results and clinical presentation.

Correct Answer: A

Rationale: The correct answer is A: ADH deficiency. Diabetes insipidus is caused by a deficiency of antidiuretic hormone (ADH), leading to excessive urine production and thirst. ADH is responsible for regulating water reabsorption in the kidneys. When ADH levels are low or absent, the kidneys cannot concentrate urine effectively, resulting in excessive urine output. Explanation for why other choices are incorrect: B: ADH excess would not lead to diabetes insipidus, as it would result in increased water reabsorption and concentrated urine. C: ADH insensitivity refers to a condition where the body does not respond to ADH, but it does not cause diabetes insipidus. D: ADH replacement therapy is actually a treatment for diabetes insipidus, not a mechanism for its development.

Correct Answer: D

Rationale: Correct Answer: D Rationale: In diabetic emergencies, starting IV dextrose at 250 mg/dL prevents hypoglycemia while resolving ketoacidosis. Below 250 mg/dL, the body can use endogenous glucose, so IV dextrose is not necessary. Summary: A: Incorrect. Normal saline may be used for initial fluid resuscitation but does not address the need for glucose. B: Incorrect. Starting dextrose at 70 mg/dL may lead to unnecessary hyperglycemia and complications. C: Incorrect. Waiting until 150 mg/dL delays the provision of necessary glucose for metabolic functions.

Correct Answer: D

Rationale: The correct answer is D: 1 to 2 L/day. Normal urine output typically ranges from 1 to 2 liters per day, which is considered adequate for maintaining proper hydration and eliminating waste products. A: 80 to 125 mL/min is too low for daily output. B: 180 L/day is excessively high and unrealistic. C: 80 mL/min is also too low for daily urine output. Therefore, D is the most appropriate choice based on standard guidelines for urine excretion.

Correct Answer: A

Rationale: The correct answer is A: fluid retention of 1.5 liters. The weight gain from 5 kg to 99 kg indicates an increase of 94 kg. Since 1 kg of weight gain is approximately equal to 1 liter of fluid retention, the patient has retained 94 liters of fluid. Therefore, the correct choice is fluid retention of 1.5 liters. Choice B is incorrect because the weight gain indicates fluid retention, not loss. Choice C is incorrect as it mentions equal intake and output, which does not match the weight gain observed. Choice D is incorrect as it suggests fluid loss, which contradicts the weight gain.

Correct Answer: A

Rationale: The correct answer is A (Blood glucose >1000 mg/dL) because diabetic ketoacidosis is characterized by severe hyperglycemia. High blood glucose levels (>1000 mg/dL) are common due to insulin deficiency leading to increased glucose production. B: Negative ketones in the urine would be incorrect as DKA results in ketone production, leading to ketonuria. C: Normal anion gap would be incorrect as DKA typically presents with an elevated anion gap metabolic acidosis due to ketone accumulation. D: pH 7.24 would be incorrect as DKA would present with a lower pH due to metabolic acidosis.

Correct Answer: A

Rationale: The correct answer is A because acute kidney injury from postrenal etiology is caused by obstruction of the flow of urine, leading to back pressure and damage to the kidneys. Choices B and C relate to prerenal causes, affecting renal perfusion and volume status. Choice D refers to intrinsic renal causes, directly affecting kidney tissue function, not postrenal obstruction. Therefore, A is correct due to the nature of postrenal etiology.