Simple Steps to Improve NIBP Measurement for Critically Ill Patients

Both hyper- and hypotension can affect the function of vital organs; thus, the measurement—and often management—of blood pressure (BP) is performed in the case of essentially every acute or critically ill patient. Most commonly, arterial BP is measured through intermittent, noninvasive means (NIBP) using an air-filled occluding upper-arm cuff.¹

Intermittent NIBP can either be measured manually or automatically. Manual BP measurement using a cuff is performed in two ways. The first, palpation, requires the involvement of a practitioner trained in detecting the radial pulse and who measures only the systolic pressure. Separately, auscultation can measure both the systolic and diastolic pressures and similarly requires a trained practitioner as well as a stethoscope and a relatively quiet environment.¹

Automated measurements of NIBP can be taken via the application of an oscillometric technique that automatically inflates the cuff to a preset value. As the pressure is gradually reduced, an algorithm applied to elucidate the change in oscillations in the cuff vessel establishes the values for the systolic and diastolic pressures.¹ However, while the process itself seems very straightforward, obstacles to achieving optimal blood pressure measurement persist.

Challenges and concerns: selecting cuff size and avoiding deadly cross-contamination

The detection of even minute variations in BP is crucial to the management of medical conditions such as hypertension, diabetes, and renal disease. The use of accurate, well-maintained devices and properly selected cuffs are critical for obtaining reliable measurements.²

The selection of an incorrect cuff size is the most common error associated with NIBP measurement. In particular, the use of cuffs that are too short or too narrow can lead to a substantial overestimation of BP.^2,3 The American Heart Association recommends using an inflatable bladder with a length that is 80% of the patient's arm circumference and a width that is at least 40% of the same. Errors are minimized further if the bladder width is exactly 46% of the arm circumference, but this is not always practical. Obese patients necessitate the use of cuffs that are longer and wider so as to properly achieve compression of the brachial artery. For children, bladder width should be at least 40% of the arm circumference and the cuff should cover at least 80% of the arm circumference.²

Despite the ubiquitous nature of NIBP measurement and the frequent use of BP equipment, cuffs may be routinely ignored or inadequately handled during cleaning.^4,5 One study showed that more than half (58.3%) of BP cuffs sampled harbored potentially pathogenic organisms, including methicillin-sensitive Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Clostridioides difficile.⁶ These bacteria can remain viable on medical equipment for days.⁷

The common or shared use of noncritical patient-care equipment is being recognized as a potential source of hospital-acquired infections.^8,9 Incorporating alternative devices, including single-use or limited-use disposable BP cuffs, has been recommended to help reduce potential cross-contamination and prevent the spread of infection.⁸ Research indicates that the increased costs associated with disposable cuffs in comparison with reusable ones actually ultimately lead to financial benefits long-term because of the decrease in associated infections, improvements in patient outcomes, and reduction in mortality rates.⁹

GE Healthcare solutions for NIBP monitoring

GE Healthcare DINAMAP SuperSTAT™ pulse matching and step deflation algorithm accurately recognizes a lack of a systolic pressure. The algorithm then causes the cuff to immediately re-inflate and search and identify the systolic pressure. This speeds up the process of monitoring unlike many other solutions, which must re-engage an entire cycle if a systolic pressure is not identified.

GE Healthcare offers a portfolio of BP cuffs that are suitable for a wide variety of patient needs and body sizes, are appropriate for clinical workflow, and which optimize safety and accuracy.

CRITIKON™ single-use cuffs are made of a soft, latex-free material that has rounded corners, maximizing patient safety and comfort. Limited-use cuffs are made of a vinyl that can withstand repeated inflation.

Single-patient and limited-use CRITIKON BP cuffs facilitate improved infection control and are available in many sizes. The full range—which includes infant, child, child long, small adult, small adult long, adult, adult long, large adult, large adult long, and thigh configurations—ensures that accurate measurements can be achieved in every patient.

These cuffs may be disposed of after a single use or incorporated into a limited-reuse protocol for patients with longer-term hospital stays.

Of particular advantage, GE Healthcare's ability to offer the first clinically validated blood pressure cuff for bariatric patients: the RADIAL-CUF. The wrong cuff size can affect accuracy up to 30 mmHG2. According to the American Heart Association, it is recommended that a cuff bladder width be 40% of the arm circumference and that a cuff bladder length be 80% of the arm circumference -- so this variation in sizing can be important for clinicians to have on hand to accurately read blood pressure of obese patients. GE designed this new cuff specifically for the forearm—with a different length to width ratio for the bladder size.

This accuracy extends to the smallest patients, as well. The dual hose tubing configuration segregates inflation and deflation from measurement, which reduces the potential impact of artifacts you would have with a single hose tube – a common issue in neonatal patients.

The verdict is clear: GE Healthcare's NIBP technology can help you take quick and accurate BP readings.

References

1. Meidert AS, Saugel B. Techniques for non-invasive monitoring of arterial blood pressure. Front Med (Lausanne). 2018;4:231. Published 2018 Jan 8. DOI: 10.3389/fmed.2017.00231. Accessed October 2, 2019.
2. Smith L. New AHA recommendations for blood pressure measurement. Am Fam Physician. 200;72(7):1391–1398.DOI: 10.1111/j.1524-6175.2005.04097.x. Accessed October 2, 2019.
3. American Association of Critical Care Nurses [no authors listed]. Obtaining accurate noninvasive blood pressure measurements in adults. Crit Care Nurse. 2016;36(3):e12–e16. DOI: 10.4037/ccn2016590. Accessed October 2, 2019.
4. Beard MA, McIntyre A, Rountree PM. Sphygmomanometers as a reservoir of pathogenic bacteria. Med J Aust. 1969;2(15):758–760. DOI: 10.5694/j.1326-5377.1969.tb107383.x. Accessed October 2, 2019.
5. Base-Smith V. Nondisposable sphygmomanometer cuffs harbour frequent bacterial colonization and significant contamination by organic and inorganic matter. AANA J. 1996;64(2):141–145. Accessed October 2, 2019.
6. Walker N, Gupta R, Cheesbrough J. Blood pressure cuffs: friend or foe? J Hosp Infect. 2006;63(2):167–169. DOI: 10.1016/j.jhin.2005.10.019. Accessed October 2, 2019.
7. Cormican MG, Lowe DJ, Keane P, Flynn J, O'Toole D. The microbial flora of in-use blood pressure cuffs. Ir J Med Sci. 1991;160(4):112–113. DOI: 10.1007/bf02947638. Accessed October 2, 2019.
8. Contact precautions in hospitals. In: Prevention and control of healthcare-associated infections in Massachusetts. Part 1: final recommendations of the Expert Panel. Boston (MA): Massachusetts Department of Public Health; (2008 Jan 31.) 50–53. Available at: http://data.patientcarelink.org/uploadDocs/1/Betsy-Leham.pdf. Accessed October 2, 2019.
9. Muto CA, Jernigan JA, Ostrowsky BE, et al. SHEA guideline for preventing nosocomial transmission of multidrug-resistant strains of Staphylococcus aureus and Enterococcus. Infect Control Hosp Epidemiol. 2003;24(5):362–386.DOI: 10.1086/502213. Accessed October 2, 2019.
10. Friedman B. Improving quality of care: justifying the cost for a single-patient-use blood pressure cuff. Available at: https://www.gehealthcare.com/white-paper/improving-quality-of-care-just…. Accessed October 2, 2019.