问题
单项选择题
While auscultating heart sounds of a client with heart failure, the nurse hears an extra heart sound immediately after the second heart sound (S2). The nurse should document this as
A. a first heart sound (S1).
B. a third heart sound (S3).
C. a fourth heart sound (S4).
D. a murmur.
答案
参考答案：B
解析：An S3 is heard following an S2, which commonly occurs in clients experiencing heart failure and results from increased filling pressures. An S1 is a normal heart sound made by the closing of the mitral and tricuspid valves. An S4 is heard before an S1 and is caused by resistance to ventrieular filling. A murmur is heard when there’s turbulent blood flow across the valves.