Drugstore Blood Pressure Machines May Not Be Dependable
Vita-Stat, a division of Spacelabs Medical, manufactured 23 of the 25 machines tested. The other two machines were Health Clinic Cardio-Analysis devices.
Karyn Beckley, vice president of corporate administrative services at Vita-Stat, tells WebMD that the Association for the Advancement of Medical Instrumentation (AAMI) publishes standards for the accuracy of blood pressure measuring devices. To meet AAMI standards, readings from devices must consistently be within plus or minus 5 mm Hg. "[Our] machines all meet the AAMI standards," she says.
Since 1993, the American College of Physicians says patients should not rely on blood pressure readings from self-monitoring blood pressure devices, and Beckley agrees the machines are no substitute for a doctor's care. "It is a way to check on your blood pressure for free in between doctor's visits," she says. "Still, our machines take 200 million readings per year nationwide, and we have had a number of times consumers have been alerted of a problem."
Van Durme says the manufacturers of the devices should monitor the accuracy and reliability of the devices frequently and make maintenance information readily available. Beckley says each individual machine is calibrated on a scheduled basis. She also says Vita-Stat has a 24-hour service organization nationwide to handle calls about defective machines.
"Anytime a person believes a machine is inaccurate, they just need to tell the pharmacist and he can report the problem to us," Beckley says.
- A new study shows that blood pressure machines found in drugstores are often inaccurate, especially if a person's arm is larger or smaller than average.
- A spokeswoman for one of the manufacturers argues that the machines all meet industry standards and help patients monitor blood pressure between doctor visits.
- Since 1993, the American College of Physicians has advised against relying on self-monitoring blood pressure devices.