|
 |
| Published | © RAmEx Ars Medica, Inc. All rights reserved. |
|
|
 Americans with high blood pressure may need to have their readings double checked
There is an increasing public health concern that new devices that measure blood pressure are poor replacements for the old-fashioned, mercury-gauged cuffs. "Sometimes these new devices give readings that are very wrong. If we don't know whether we as physicians have an accurate reading, we can't be sure patients are receiving proper -- even safe -- treatments," said Dr. Daniel W. Jones, an internationally known hypertension expert who is high blood pressure spokesman for the American Heart Association (AHA). Jones also is associate vice chancellor for health affairs at the University of Mississippi Medical Center (UMC) in Jackson. A public health alert about the devices recently was issued in a joint statement from the AHA, with spokesman Jones, and the National Heart, Lung and Blood Institute (NHLBI) of the National Institutes of Health. Since mercury is a toxic pollutant that needs proper disposal, hospitals and physicians nationwide have been returning mercury-gauged sphygmomanometers to their manufacturers to comply with a 1998 federal waste reduction standard. Mercury-gauged arm cuff units -- known for trouble-free readings -- gradually are being replaced with less-reliable aneroid (with a dial reading) or least-reliable electronic (with a digital reading) arm cuff units. The problem with the new models is that they are more apt to become inaccurate with prolonged use -- or if dropped or bumped. Even brand new models have been found to be inaccurate. Inaccurate readings from the non-mercury devices can be as high as 50 (diastolic or systolic) points in some patients, especially the elderly, Jones said. The ramifications may be false diagnosis and, subsequently, improper treatment of patients -- leading to severe problems. For patient safety, readings for the new models frequently need to be verified against a mercury reading and, if necessary, recalibrated. Often, recalibration requires the new devices to be returned to their manufacturers. Such problems mean American hospitals need to enforce a whole new safety system to ensure the new devices' accuracy, Jones said. U.S. hospitals generally are unprepared, said Jones and Dr. Claude Lenfant, earlier speaking for the NHLBI, as its director. Such in-house hospital safety systems require some vigilance since sphygmomanometers are in such frequent use (and, therefore, possibly damaged) and sometimes portable and apt to move among clinics. To ensure the veracity of newer devices, UMC keeps a mercury-gauged unit in every clinical site and has newer devices verified at least annually and, if needed, recalibrated according to manufacturers' guidelines, said Chief Nursing Officer Lyn Sanderford, who oversees nursing standards. The maintenance system has been in place at UMC for several years. Jones said hypertensive patients may continue to use the newer sphygmomanometers at home, but should take them to their physician's office annually to verify readings match a mercury-gauged unit or another professionally maintained model. Wrist and finger cuffs are less accurate than arm cuffs and their use is discouraged, he added. |
||
