The nurse is caring for a postoperative client who has a chest tube connected to suction and a water seal drainage system. Which of the following indicates to the nurse that the chest tube is functioning properly?

Choice A Reason: Observing for cerebrospinal fluid (CSF) leaks from the evacuation site is important, but not the first action that the nurse should take. CSF leaks can indicate a breach in the dura mater, which can increase the risk of infection and meningitis. The nurse should inspect the dressing and the nose and ears for any clear or bloody drainage, and report any findings to the provider. However, these measures are secondary to ensuring adequate oxygenation and perfusion.

Choice B Reason: Checking the oximeter is also important, but not the first action that the nurse should take. The oximeter measures the oxygen saturation of the blood, which reflects the adequacy of gas exchange in the lungs. The nurse should maintain the oxygen saturation above 90%, and administer supplemental oxygen as prescribed.

However, these measures are secondary to ensuring adequate oxygenation and perfusion.

Choice C Reason: Assessing for an increase in temperature is another important action, but not the first one that the nurse should take. An increase in temperature can indicate an infection, inflammation, or damage to the hypothalamus, which can affect the thermoregulation of the body. The nurse should monitor the temperature and administer antipyretics as prescribed. However, these measures are secondary to ensuring adequate oxygenation and perfusion.

Choice D Reason: Monitoring for manifestations of increased intracranial pressure is the first action that the nurse should take. Increased intracranial pressure can result from bleeding, swelling, or fluid accumulation in the brain, which can compress and damage brain tissue and blood vessels. The nurse should assess for signs and symptoms of increased intracranial pressure, such as headache, nausea, vomiting, altered level of consciousness, pupillary changes, or Cushing's triad (bradycardia, hypertension, and irregular respirations). The nurse should also intervene to prevent or reduce increased intracranial pressure, such as elevating the head of the bed, maintaining normothermia, and administering osmotic diuretics. Monitoring for manifestations of increased intracranial pressure is essential to prevent further brain injury and preserve neurological function.

Choice A Reason: This choice is incorrect because it indicates respiratory alkalosis, not AKI. Respiratory alkalosis is a condition in which the lungs eliminate too much carbon dioxide (CO2) from the blood, resulting in a low level of CO2 (PaCO2) and a high level of pH. A normal PaCO2 range is 35 to 45 mm Hg, and a normal pH range is 7.35 to 7.45, so a value of 30 mm Hg and 7.49 indicate respiratory alkalosis.

Choice B Reason: This choice is incorrect because it indicates respiratory acidosis, not AKI. Respiratory acidosis is a condition in which the lungs cannot eliminate enough CO2 from the blood, resulting in a high level of CO2 (PaCO2) and a low level of pH. A value of 46 mm Hg and 7.26 indicate respiratory acidosis.

Choice C Reason: This choice is correct because it indicates metabolic acidosis, which is a common complication of AKI. Metabolic acidosis is a condition in which the body produces too much acid or loses too much base, resulting in a low level of bicarbonate (HCO3) and a low level of pH. A normal HCO3 range is 22 to 26 mEq/L, so a value of 14 mEq/L indicates metabolic acidosis. The low PaCO2 value (30 mm Hg) is due to the respiratory compensation mechanism that tries to restore the acid-base balance by increasing the ventilation and eliminating more CO2.

Choice D Reason: This choice is incorrect because it indicates metabolic alkalosis, not AKI. Metabolic alkalosis is a condition in which the body loses too much acid or gains too much base, resulting in a high level of bicarbonate (HCO3) and a high level of pH. A value of 30 mEq/L and 7.49 indicate metabolic alkalosis.