Adult Critical Care Specialty (ACCS) Practice Exam

In the context of a patient on continuous mechanical ventilation with large bilateral pleural effusions, what condition is most likely indicated by oliguria and elevated creatinine levels?

1. Cardiac failure

2. Renal failure

3. Heart failure

4. Diabetic ketoacidosis

The correct answer is: Renal failure

In a patient undergoing continuous mechanical ventilation who also presents with large bilateral pleural effusions, oliguria and elevated creatinine levels are strong indicators of renal insufficiency or failure. Oliguria, defined as a decreased urine output, often suggests that the kidneys are unable to function adequately, which can lead to an accumulation of waste products such as creatinine in the blood. Elevated creatinine levels are a specific marker of kidney function; when the kidneys are impaired, creatinine levels rise due to reduced clearance from the bloodstream. Additionally, in the context of mechanical ventilation and large pleural effusions, the patient might be experiencing compromised organ perfusion due to fluid shifts and potential cardiac involvement, but this does not directly lead to elevated creatinine. The most straightforward interpretation of oliguria and high creatinine in this scenario points towards renal failure, as it directly reflects the state of the kidneys rather than interventions or complications arising from other systems, such as heart function. While cardiac failure and heart failure could potentially lead to renal impairment through reduced perfusion, the presence of oliguria and elevated creatinine levels distinctly signals renal failure rather than a secondary effect from cardiac issues. Diabetic ketoacidosis typically presents with metabolic derangements but would not primarily manifest as elevated creat