14.13: Special considerations while measuring blood pressure
When assessing blood pressure (BP), healthcare professionals must consider various factors and potential unexpected outcomes to ensure accurate readings and provide proper patient care. Adhering to these guidelines is essential to achieving the most reliable results.
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.
Positional Differences:
Diastolic pressure is approximately five millimeters of mercury higher when measured in a sitting position than a supine one. Systolic pressure is about eight millimeters of mercury higher in the sitting position than when assessed supine.
Interventions for Abnormal Sounds:
In situations with abnormally high or low Korotkoff sounds, consider proper patient positioning, check stethoscope placement, verify device accuracy, and ensure a quiet environment. Repeat the procedure after two to three minutes and report any abnormal results to the care provider.
Clinical Assessment:
When blood pressure is outside the acceptable range, assess for symptoms such as tachycardia, a weak or thready pulse, dizziness, confusion, and pale or cyanotic skin.
Enhancing Korotkoff Sounds:
For weak or inaudible sounds, raise the patient's arm with the cuff overhead for thirty seconds before rechecking the blood pressure. Inflate the cuff and gently lower it while supporting it, enhancing Korotkoff sounds by reducing vascular volume and improving blood flow.
Auscultatory Gap:
During the manual measurement of BP by the auscultatory method, note the brief disappearance of Korotkoff sounds interval between the systolic and diastolic pressures during cuff deflation. It defines an auscultatory gap and indicates vascular stiffness. To obtain an accurate reading, palpate the radial artery and simultaneously increase the cuff pressure to a level above the disappearance of the pulse, followed by Korotkoff sounds auscultation during gradual cuff deflation. Document the auscultatory gap and ensure other healthcare workers know it to prevent future errors.
Caution with Electronic Devices:
Many electronic devices are not advisable for patients with irregular heart rates, tremors, or an inability to keep extremities still, emphasizing the importance of selecting appropriate methods based on individual patient characteristics.
