Blood pressure measurement devices are categorized as: manual sphygmomanometers, digital non-portable for upper arm with automatic inflation, digital portable for upper arm with automatic inflation, digital portable for wrist with automatic inflation, and digital portable for finger with automatic inflation. In past testing by Consumer Reports, 16 brand devices were tested with trained medical personnel conducting 6,000 readings on 57 men and women. The upper arm cuff devices were found to be more accurate than wrist devices. The American Heart Association recommends an automatic, cuff-style, upper-arm monitor. Omron (Figure 1) continues to be rated high by Consumer Reports. Recent testing by Consumer Reports also rated Rite Aid and iHealth high for accuracy.
For manual sphygmomanometers, the sphygmomanometer (blood pressure cuff or machine) consists of an inflatable cuff and two tubes; one tube is connected to the pressure hand control bulb and the other tube to the pressure gauge (Figure 2). The size of the patient determines the size of the cuff selected. There are several cuff sizes. The cuff width should be 20% greater than the diameter of the arm. When a cuff is too narrow, the blood pressure reading is too high; when the cuff is too wide, the reading is too low.
The stethoscope, a listening aid that magnifies sound is used with manual devices and consists of two earpieces that are connected by tubes that carry the sound to the earpieces from the end piece, which is placed over the artery (Figure 3).