An adult male is admitted to the cardiovascular intensive care unit (CV-ICU) following an acute myocardial infarction (AMI). His wife is at the bedside when the client goes unresponsive, the monitor alarms and displays ventricular fibrillation (VF). The resuscitation team rushes into the client's room and when the wife is asked to wait in the waiting area, she refuses to leave. Which action should the nurse take?

Rationale:
A. Determine when symptoms began and if improved or worsened since onset: In suspected stroke, the timing of symptom onset is critical for determining eligibility for interventions such as thrombolytic therapy. Assessing whether symptoms are improving or worsening guides immediate treatment decisions and is the highest priority.

B. Administer aspirin to prevent further clot formation and platelet clumping: Administering aspirin may be contraindicated if the stroke is hemorrhagic. The type of stroke must first be determined via imaging before giving antiplatelet therapy.

C. Verify prescribed laboratory tests include prothrombin time and platelet count: Lab tests are important for baseline data and to guide future treatment, but they do not take priority over determining the timing and progression of neurological symptoms.

D. Keep the bed in the lowest position and initiate seizure and fall precautions: Safety measures are important to prevent injury but are secondary to establishing the timeline and nature of the neurological event, which drives urgent treatment.

Rationale:

A. Partial pressure of oxygen of 50 mm Hg: A PaO₂ of 50 mm Hg is below the normal range (80–100 mm Hg) and indicates hypoxemia. This does not reflect improvement with fluid resuscitation and would require supplemental oxygen or further interventions.

B. Positive result on passive leg raise challenge: A positive response indicates that the client is fluid responsive, meaning cardiac output increases with fluid administration. This reflects improved perfusion and effective intravascular volume expansion.

C. Peripheral pulses of 2+: Palpable, normal-strength pulses suggest improved perfusion to the extremities following fluid resuscitation. This indicates that intravascular volume and cardiac output have been enhanced.

D. Mixed venous oxygen saturation of 70%: A SvO₂ around 70% reflects adequate oxygen delivery relative to tissue oxygen consumption. This indicates that perfusion and oxygenation have improved after fluids.

E. Mean arterial pressure (MAP) between 70 to 80 mm Hg: MAP in this range demonstrates adequate systemic perfusion. Restoration of MAP is a key goal of fluid resuscitation in septic or hypovolemic states.

F. Central venous pressure of 9 mm Hg: CVP in the range of 8–12 mm Hg suggests adequate right-sided filling and intravascular volume after fluid administration.

G. Urine output greater than 0.5 mL/kg/hour: Adequate urine output is an important indicator of improved renal perfusion and intravascular volume following fluid resuscitation.

H. Capillary refill of greater than 3 seconds: Prolonged capillary refill indicates poor peripheral perfusion. Improvement would be reflected by capillary refill of ≤2 seconds, so a value >3 seconds does not indicate improvement.