A client with chronic lung disease is prescribed 40% oxygen via face mask. Which finding indicates to the nurse that the client is experiencing oxygen toxicity? Select all that apply.

Choice A reason: An increase in temperature is not a primary indicator of hypovolemic shock. While fever can occur due to infection or inflammation, it is not directly related to hypovolemic shock, which is primarily characterized by a significant loss of blood or fluids leading to decreased perfusion and oxygenation of tissues.

Choice B reason: A decrease in urinary output is a critical sign of hypovolemic shock. When the body loses a significant amount of blood or fluids, the kidneys receive less blood flow, leading to reduced urine production. This is a compensatory mechanism to conserve fluids and maintain blood pressure. Normal urine output is typically around 30 to 50 mL per hour, so a drop below this range is concerning.

Choice C reason: An increase in heart rate is a common response to hypovolemic shock as the body attempts to maintain cardiac output and blood pressure despite the loss of blood volume. Tachycardia (increased heart rate) is one of the early signs of shock, indicating that the heart is working harder to pump blood to vital organs.

Choice D reason: A decrease in respiratory rate is not typical of hypovolemic shock. In fact, hypovolemic shock often leads to an increased respiratory rate (tachypnea) as the body tries to compensate for decreased oxygen delivery to tissues. A decrease in respiratory rate could indicate other issues but is not a hallmark of hypovolemic shock.

Choice A: Tachycardia

Tachycardia, defined as a heart rate exceeding 100 beats per minute, can affect the accuracy of pulse oximetry readings. When the heart beats too quickly, it may not fill with enough blood between beats, leading to reduced perfusion and oxygen delivery to tissues. However, while tachycardia can influence the readings, it is not the most significant factor compared to hypotension.

Choice B: Hypotension

Hypotension, or low blood pressure, significantly impacts pulse oximetry accuracy. When blood pressure is low, there is reduced perfusion to peripheral tissues, including the extremities where pulse oximeters are typically placed. This reduced perfusion can lead to inaccurate readings, as the device may not detect sufficient blood flow to measure oxygen saturation accurately. Hypotension is a critical factor that can alter pulse oximetry values, making it the most relevant choice.

Choice C: Tachypnea

Tachypnea, or rapid breathing, can affect oxygen levels in the blood but does not directly interfere with the pulse oximeter’s ability to measure oxygen saturation. While it indicates respiratory distress and can lead to hypoxemia, the pulse oximeter can still provide accurate readings unless accompanied by other factors like low perfusion.

Choice D: Fever

Fever can cause peripheral vasodilation, which might theoretically affect pulse oximetry readings by altering blood flow to the extremities. However, this effect is generally minimal compared to the impact of hypotension. Fever alone is unlikely to cause significant inaccuracies in pulse oximetry measurements.