The nurse is assisting with a subclavian vein central line insertion when the client’s oxygen saturation rapidly drops. He complains of shortness of breath and becomes tachypneic. The nurse suspects a pneumothorax has developed. Further assessment findings supporting the presence of a pneumothorax include（）
A. diminished or absent breath sounds on the affected side.
B. paradoxical chest wall movement with respirations.
C. tracheal deviation to the unaffected side.
D. muffled or distant heart sounds.
参考答案：A
解析：
In the case of a pneumothorax, auscultating the breath sounds will reveal absent or diminished breath sounds on the affected side. Paradoxical chest wall movements occur in flail chest conditions. Tracheal deviation occurs in a tension pneumothorax. Muffled or distant heart sounds occur in pericardial tamponade.