When a 75-year-old woman came to an emergency department (ED) complaining of severe headache, her blood pressure was taken with the wrong size cuff. "She measured a much higher blood pressure than actual and was treated for a hypertensive emergency with vasodilators," says Karen Hayes, PhD, ARNP, professor at the school of nursing at Wichita (KS) State University. "This lowered the blood pressure quickly and only exacerbated her headache, which was benign." In addition, the woman spent the night in the hospital as she was too weak to go home until her blood pressure returned to normal, says Hayes.
The above example shows the importance of accurately measuring vital signs in older patients, says Hayes. Here are some items to consider:
• Blood pressure checks.
Elderly patients can benefit from antihypertensive drug therapy, so it’s especially important that your reading be accurate, Hayes says. Systolic hypertension is especially prevalent and dangerous in the elderly and should be treated even if the diastolic is below 90 mm Hg, she says. "Multiple blood pressures are necessary before confirming hypertension in the elderly, whose blood pressure is often labile," says Hayes. She cautions that the following can make readings inaccurate:
— The patient’s position. You should monitor blood pressure both standing and seated, to avoid inaccurate readings due to postural hypotension, Hayes says.
— The size of the blood pressure cuff. These factors can greatly affect the accuracy of blood pressure readings, says Hayes. She explains that if the cuff is too small or too large, the measurements will be inaccurate. "As a general rule, the inflatable part of the cuff needs to be at least as long as the widest measurement around the upper arm," she says.
— Movement by the patient. Be sure the patient does not move or talk while you are measuring the blood pressure, Hayes advises. "Be aware that the blood pressure readings may be 10-to 20-mm Hg different between the right arm and your left arm," she says. However, if the difference is more than 20 mm, it should be reported, she says.
— The time of day. Blood pressure readings vary throughout the day, notes Hayes. "They usually are highest in the morning, decrease throughout the day, and are lowest in the evening," she points out.
The patient’s pulse should be taken for a full minute to assess for irregularity and changes in rate, Hayes says. "Auscultating the heart may be difficult in some elders," she says. "Having the patient lean forward helps to hear heart tones." She also recommends assessing the pulse in both wrists to assess circulation.
Oral and axillary temperature readings are acceptable for assessment in patients with normal or low-grade fever, she says. However, elders with high fever should have auditory canal or rectal temperatures taken, because oral and axillary readings may lag 45 minutes behind. "For auditory temperatures, be sure the probe is facing the eardrum for accuracy," she says.
Orthostatic hypotension is a common problem in the elderly, who may present with dizziness and syncope, and who fall upon changing position, says Nina M. Fielden, MSN, RN, CEN, an ED clinical nurse specialist at The Cleveland Clinic Foundation. However, ED nurses sometimes forget to do orthostatics on certain patients, such as elderly patients who have a fever, Fielden says. "Many of our elderly suffer from urinary tract infections that they don’t know they have, and this can cause confusion as well as dehydration," she says.
You may be doing the measurement wrong, she cautions. "It is not necessary to go from lying to sitting to standing. It is more effective to go from lying to standing," she says. As result, Fielden says, this may be difficult to do at triage, and instead, it should be done when the patient is in a room and can lie down for several minutes before standing. If the patient cannot stand, then dangling at the bedside is an acceptable alternative, Fielden says. Also, most times, the orthostatic measurement is recorded the minute the patient stands up, Fielden says. "This is not as accurate, as many of us normally have a transient drop in blood pressure when standing," she says.
The true measurement comes if the patient is truly orthostatic after standing for one minute, when the body has a chance to adjust, she explains. The patient must be lying down for several minutes, then standing up for one full minute before the measurement is taken, she says. The way to accurately measure postural vital signs is to measure supine blood pressure, systolic and diastolic, and pulse rate after the patient has lain flat for two to five minutes, Fielden says.
"If the patient cannot lay completely supine, assist the patient to lie as flat as is comfortable," she says. The patient then should be helped to a standing position or sitting with legs dangling, if unable to stand, with the measurement of postural vital signs after one complete minute, Fielden says. "It is recommended that the pulse be counted for 30 seconds and doubled, rather than for 15 seconds," notes Fielden.
She says the following are positive orthostatic signs:
- a drop of more than 20 to 25 mm Hg in systolic measurement;
- a drop of more than 10 mm Hg of diastolic measurement;
- an increase in pulse rate of over 20 beats.
"If the patient is on a cardiac monitor, note the regularity or irregularity of the heart rate, and the rhythm," says Fielden.
For more information about assessment of vital signs in elderly patients, contact:
• Nina M. Fielden, MSN, RN, CEN, Clinical Nurse Specialist, Emergency Department, Cleveland Clinic Foundation, 9500 Euclid Ave., E19, Cleveland, OH 44195. Telephone: (216) 444-0153. Fax: (216) 444-9734. E-mail: email@example.com.
• Karen Hayes, PhD, ARNP, School of Nursing, Wichita State University, 1845 Fairmount, Wichita, KS 67260.Telephone: (316) 978-5721. E-mail: Karen.Hayes@wichita.edu.