The nurse admits a patient to ICU with a gastrointestinal bleed with a week long history of vomiting and diarrhea. The patient has a Pulmonary Artery (PA) catheter in place. A fluid bolus is initiated to treat which underlying issue?

A. Increased preload: Preload refers to the volume of blood returning to the heart. In this patient, hypovolemia from vomiting, diarrhea, and gastrointestinal bleeding reduces circulating volume rather than increasing it, so increased preload is not the underlying issue. B. Decreased afterload: Afterload is the resistance the left ventricle must overcome to eject blood. While hypovolemia may indirectly affect afterload, fluid resuscitation primarily targets restoring intravascular volume and preload, not directly correcting afterload. C. Decreased preload: The patient’s prolonged fluid losses have led to hypovolemia, resulting in decreased venous return and reduced preload. Administering a fluid bolus increases circulating volume, improves ventricular filling, and enhances cardiac output, which is critical in hypovolemic shock. D. Increased afterload: Increased afterload is usually seen in hypertension or vasoconstrictive states and is not the primary concern in a patient with fluid loss. Treating hypovolemia with fluids does not target elevated afterload but restores adequate preload for perfusion.