Over the years, the devices used to measure blood pressure have become more sophisticated and user friendly. This has enabled the monitoring of blood pressure to b be conducive and somewhat enjoyable outside the traditional hospital setting.

The devices widely used to measure blood pressure today are:
· Mercury sphygmomanometer
· Aneroid sphygmomanometer
· Semi-automated device
· Automated device
· Wrist device
· Finger device
· Automatic non invasive blood pressure (NIBP) Monitor
· Ambulatory blood pressure monitor

There are numerous advantages to be gained from using these devices. However their use is not without some drawbacks.

MECURY SPHYGMOMANOMETER
This device consists of an upper arm cuff with two rubber tubing leading to both a mercury column and an inflation bulb (with an inflation control valve). A stethoscope is required to listen to the korotkoff sounds.
Mercury sphygmomanometry is still considered the "gold standard" by many health care professionals. It is portable, easy to use and can be used on most patients. However, there have been concerns in recent years about potential mercury toxicity in users of this device. Furthermore, this device can be prone to observer bias.

ANEROID SPHYGMOMANOMETER
This device makes use of an aneroid gauge instead of a mercury manometer. It can either be desk mounted or attached to the hand bulb. It is mercury free, portable and easily understood by users. However it can be prone to observer bias and requires regular calibration.

SEMI-AUTOMATED DEVICE
The device consists of an electronic monitor and pressure sensor, an upper arm cuff and a digital display. It is usually battery powered. The cuff is inflated by the hand bulb and the systolic and diastolic pressures are displayed after automatic deflation of the cuff. Pulse rate may also be displayed.
This device is mercury free, portable and easy to use. It is also free of observer bias. Sadly, it is difficult to calibrate and may not be suitable for all patients particularly those with arrhythmias.

AUTOMATED DEVICES
This device is similar to the semi-automated device but a hand bulb is absent. An electrically driven pump raises the pressure in the cuff. Certain models may have user adjustable set inflation pressure and a memory facility. It is battery powered, portable, mercury free and easy to use. It has the same drawbacks as the semi-automated device.

WRIST DEVICE
This device includes an electronic monitor with a pressure sensor, an electrically driven pump and a wrist cuff. The device itself may be attached to the wrist. Its function is similar to the automated device. It is portable to use, user- friendly and free of observer bias. However, readings are dependent on the relative positioning of the wrist to the heart.

FINGER DEVICE
This device may be attached to the finger and includes an electronic monitor and a finger cuff. Its is battery powered and suitable for use in most patients.

AUTOMATIC NON INVASIVE BLOOD PRESSURE (NIBP) MONITOR
This device is designed for clinical use. It is an improvement of the automated devices described above with the addition of an automated facility to monitor the patient's blood pressure at set time intervals. It is usually equipped with an alarm system to alert nursing staff when one or more patient functions have exceeded normal limits.
It is battery operated and suffers from no observer bias. It is transportable and easy to operate. Its major drawback is that it is expensive and this may restrict its global acceptability.

AMBULATORY BLOOD PRESSURE MONITOR
This device includes an electronic monitor with a pressure sensor, an upper arm cuff, and an electrically driven pump attached to the patient's belt. It s is battery operated and provides blood pressure readings over twenty four hours while the patient is in their own environment. Data obtained may be stored for future analysis. It is designed for clinical use.
It is mercury free, easy to use, and portable. However, special training is recommended before its use. It is also expensive and not widely available