Four hours after mechanical ventilation is initiated for a patient with a suspected drug overdose, the patient's arterial blood gas (ABG) results include a pH of 7.50, Pa0 2 of 80 mm Hg. PaCO2 of 29 mmHg, and HCO3 of 23 mEq/L (23 mmo/L). The nurse will anticipate the need to:

Lactate is a by-product of anaerobic metabolism that accumulates when there is insufficient oxygen supply to meet cellular metabolic demands. In the context of severe tissue hypoxia, such as in septic shock, the body may resort to anaerobic metabolism, leading to increased lactate production and elevated lactate levels in the blood.
Elevated lactate levels, typically above 4.0 mmol/L, are indicative of tissue hypoxia and inadequate oxygenation at the cellular level. Higher lactate levels, such as 9.0 mmol/L, suggest more severe tissue hypoxia and increased anaerobic metabolism.
A. Partial thromboplastin time (PTT) 64 seconds in (option A) is incorrect because: PTT is a laboratory test that evaluates the intrinsic pathway of the coagulation cascade. While coagulation abnormalities may occur in septic shock, PTT alone does not specifically indicate severe tissue hypoxia.
C. Potassium 2.8 mEq/L (2.8 mmol/L) (option C) is incorrect because Low potassium levels (hypokalemia) can be a concern in septic shock, but it does not directly indicate severe tissue hypoxia.
D. PaCO2 58 mm Hg in (option D) is incorrect because: PaCO2 refers to the partial pressure of carbon dioxide in arterial blood and is a measure of the respiratory status. While an elevated PaCO2 can be a sign of respiratory acidosis, it is not specific to severe tissue hypoxia.
Therefore, in a critically ill patient with septic shock, an elevated lactate level, such as 9.0 mmol/L, indicates severe tissue hypoxia and inadequate oxygenation at the cellular level

In this scenario, the patient's signs and symptoms suggest a state of shock, which can be caused by various factors, such as hypovolemia, cardiac dysfunction, or systemic vasodilation. The first priority in managing a patient in shock is to ensure adequate oxygenation and tissue perfusion. Administering oxygen at 100% per non-rebreather mask helps improve oxygen delivery to the tissues and supports vital organ function.
A. Placing the patient on a continuous cardiac monitor in (option A) is incorrect because it is an important step to monitor the patient's heart rhythm and identify any abnormalities. However, providing oxygen should take priority to address the potential hypoxemia and tissue hypoperfusion.
C. Inserting two 14-gauge IV catheters in (option C) is incorrect because it is crucial for establishing large-bore access for fluid resuscitation and medication administration. While it is an important step, addressing oxygenation takes precedence.
D. Drawing blood to type and crossmatch for transfusions in (option D) is incorrect because it is an important step in managing a patient in shock who may require blood products. However, ensuring adequate oxygenation through oxygen administration is the immediate priority.
Therefore, the nurse should act first on the order to administer oxygen at 100% per non-rebreather mask to support the patient's oxygenation and tissue perfusion.