A nurse is collecting data on a client who has pneumonia. Which of the following findings should the nurse expect?

A. ARDS is characterized by severe hypoxemia due to shunting, but it typically impairs oxygenation rather than carbon dioxide elimination. The primary issue is the inability to oxygenate blood, not the elimination of carbon dioxide.
B. In ARDS, pulmonary arterial pressure often increases due to pulmonary hypertension caused by widespread inflammation and hypoxemia, not decreased pressure. V/Q mismatch contributes to hypoxemia but does not directly cause decreased pulmonary arterial pressure.
C. While hypoxemia is a hallmark of ARDS, it is primarily due to shunting (where blood passes through unventilated areas of the lung) rather than dead space, which is more associated with conditions like pulmonary embolism.
D. ARDS involves decreased pulmonary compliance due to the stiffness of the lungs, which results from diffuse alveolar damage and the formation of hyaline membranes. This stiffness makes it difficult for the lungs to expand, leading to reduced oxygenation and severe hypoxemia.

A. The client has developed confusion: Hypotonic fluids can cause a rapid shift of water into cells, potentially leading to cerebral edema. This can manifest as confusion or altered mental status, which is a serious adverse effect requiring immediate attention.

B. The client's serum sodium is 140 mEq/L (135 to 145 mEq/L): A serum sodium level within the normal range indicates that the hypotonic fluid therapy is likely effective in correcting hypernatremia, and does not suggest an adverse effect.

C. The client has a positive Chvostek's sign: A positive Chvostek's sign is indicative of hypocalcemia rather than an adverse effect of hypotonic fluid administration. This sign is related to low calcium levels and is not a direct result of hypotonic fluid therapy.

D. The client's blood urea nitrogen (BUN) level is 18 mg/dL (10 to 20 mg/dL): This BUN level is within normal limits and does not suggest an adverse effect of hypotonic fluid therapy. BUN levels can be affected by various factors, but this value alone is not indicative of an adverse reaction.