a. Sphygmomanometer. The sphygmomanometer (figure 5-2) is usually called
the "blood pressure cuff." There are several different types of blood pressure cuffs in
use. Some are made to be attached to a wall (next to a patient's hospital bed, for
example), but most are portable. All blood pressure cuff devices work basically in the
same way and have the same parts--a bladder, a handbulb with release valve, a tube
connecting the handbulb to the bladder, and a gauge (either mercury or aneroid) for
A Portable mercury sphygmomanometer.
B Portable aneroid sphygmomanometer.
Figure 5-2. Sphygmomanometers.
(1) Bladder. The bladder (also called the "cuff") is a long rubber bag about
6 inches wide and 24 inches long that is covered with fabric. The bladder is wrapped
around the patient's arm and filled with air when taking the patient's blood pressure.
Parts of the fabric are made of non-slip material, such as Velcro. When the fabric is
overlapped, the two pieces of fabric adhere to each other and will not slip when the
bladder is inflated. Some sphygmomanometers use snaps or other devices to secure
the bladder instead of non-slip fabric.
(2) Handbulb. The handbulb is a device for inflating the bladder. When
squeezed, the handbulb forces the air through an opening connected to the tubing.
When the bulb is released, it refills with air from the environment. The handbulb is
designed so that air from the tubing cannot flow back into the handbulb.