After using a nasal cannula delivery system at 3 L/min, a patient with chronic airflow limitation (CAL) changes to a simple face mask. The nasal equipment oxygen was set at 3 L/min. How should the nurse adjust the oxygen flow for the new delivery system?

Correct Answer: D

Rationale: To determine the correct oxygen flow for a simple face mask, you should increase it from the previous nasal cannula rate. As simple face masks deliver oxygen less efficiently, a higher flow rate is needed to maintain the same oxygen concentration. Moving from 3 L/min nasal cannula to a simple face mask, you should increase the flow to 6 L/min to ensure adequate oxygen delivery to the patient with chronic airflow limitation. Choices A and B are incorrect as decreasing or keeping the flow the same would not provide sufficient oxygen. Choice C is also incorrect as increasing it to 4 L/min may not be enough to compensate for the decreased efficiency of the simple face mask.

Correct Answer: C

Rationale: The correct action for the nurse to take first is to auscultate the breath sounds (Choice C) because the client is presenting with severe dyspnea and a dry hacking cough, which are indicative of respiratory distress in a patient with chronic heart failure. Auscultating the breath sounds will help the nurse assess the presence of crackles, wheezing, or decreased air entry, providing crucial information about the client's respiratory status and guiding immediate interventions. Checking the capillary refill (Choice B) is important but not the priority in this situation. Auscultating the abdomen (Choice A) is not relevant to the presenting symptoms. Asking about the patient's allergies (Choice D) is important but can be addressed after addressing the immediate respiratory distress.

Correct Answer: C

Rationale: The correct answer is C: PN2 = 620mmHg. This is the inconsistent value because the normal partial pressure of nitrogen in venous blood is around 40 mmHg, not 620 mmHg. This discrepancy indicates an abnormal measurement. The other choices (A, B, D) are within expected ranges for a mixed venous blood sample in a healthy person at sea level. Choice A (pO2 = 40mmHg) is typical for venous blood, choice B (pCO2 = 48mmHg) falls within the normal range, and choice D (O2 content = 150ml/L blood) is a reasonable value for mixed venous blood.

Correct Answer: B

Rationale: The correct answer is B: external respiration. This is the part of respiration where oxygen and carbon dioxide are exchanged in the capillaries lining the alveoli in the lungs. During external respiration, oxygen from the alveoli diffuses into the bloodstream while carbon dioxide from the bloodstream diffuses into the alveoli to be exhaled. A: Pulmonary ventilation refers to the process of breathing, specifically the movement of air in and out of the lungs. This does not involve the actual exchange of gases in the alveoli. C: Transport of respiratory gases involves the movement of oxygen and carbon dioxide through the bloodstream to and from the tissues. This is not specifically related to the exchange of gases in the alveoli. D: Internal respiration refers to the exchange of gases between the bloodstream and the tissues at the cellular level. This does not specifically occur in the alveoli of the lungs.

Correct Answer: C

Rationale: The correct answer is C: Increased pulmonary capillary permeability. ARDS is characterized by damage to the alveolar-capillary membrane, leading to increased permeability and leakage of fluid into the alveoli. This causes bilateral white-outs on X-ray. Cardiogenic pulmonary edema (A) results from heart failure, not ARDS. Respiratory alkalosis (B) is a condition of elevated blood pH due to hyperventilation, not a direct cause of ARDS. Renal failure (D) is not a direct cause of ARDS, although it can contribute to fluid overload. Thus, the most accurate choice is C due to the pathophysiological mechanism of ARDS.