Physiological Integrity
What this domain tests
Physiological Integrity is the largest domain. It covers medical-surgical and critical care concepts, pharmacology, parenteral therapies, reduction of risk potential, and physiological adaptation. Expect questions on fluid and electrolyte balance, acid-base status, medication administration and monitoring, perioperative and post-procedure care, oxygenation, and recognizing complications early.
Concepts you must own
Know normal values and what deviations mean: potassium, sodium, calcium, and magnesium ranges; ABG interpretation (pH, PaCO2, bicarbonate) to classify respiratory versus metabolic and acidosis versus alkalosis; and the signs of fluid volume excess versus deficit. Understand high-alert medications, their monitoring parameters, and antidotes. Recognize early signs of complications such as hemorrhage, infection, shock, and increased intracranial pressure.
Traps to expect
- "Which finding is most concerning?" items where several values are abnormal; choose the one most immediately life-threatening (e.g., potassium of 6.8 mEq/L over sodium of 133 mEq/L).
- Medication items that test monitoring parameters, not just the dose or route.
- ABG questions that require compensation analysis, not only the primary disorder.
- Post-procedure items where a subtle change signals bleeding or airway compromise before overt signs appear.
Rule of thumb
For any lab or assessment question, rank findings by how quickly they can kill: airway and breathing, then cardiac rhythm and electrolyte instability, then neurologic change, then everything else.
Worked example
A client's ABG shows pH 7.28, PaCO2 30 mm Hg, and bicarbonate 14 mEq/L. The low pH indicates acidosis; the low bicarbonate points to a metabolic cause, while the low PaCO2 reflects respiratory compensation. The answer identifies metabolic acidosis with partial respiratory compensation.