Hypertension is one of the leading causes of heart disease, and it is increasingly prevalent in children. Tammy Brady, M.D., Ph.D., medical director of the pediatric hypertension program at Johns Hopkins Children’s Center, discusses her research on the importance of the size of blood pressure cuffs for accurate readings. For this research, several trials were designed to determine the effect of the patient’s positioning, preparation and cuff size for blood pressure monitoring.
My name is tammy brady and I'm a pediatric nephrologist at johns Hopkins, where I'm also the medical director of the pediatric hypertension program and I'm the vice chair for clinical research. My career focus has been on cardiovascular health promotion across the lifespan. Hypertension is one of the leading causes of cardiovascular disease and is increasingly prevalent in Children hypertension screening during preventive visits and elsewhere is essential to identifying those with hypertension. And it goes without saying that an accurate blood pressure measurement is key to correctly identifying those with hypertension and not labeling those without hypertension as having an elevated blood pressure. Even though blood pressure measurement is a key vital sign, many people don't recognize that there are many steps that are required to make sure you have an accurate blood pressure because many of those steps can take a considerable amount of time. We wanted to determine how important each of those steps were. So to do this. We designed several trials, each of which was designed to help us determine the effect of patient positioning, preparation and cuff size on blood pressure measurement. The first of those studies um, was designed to determine the impact of resting for five minutes on blood pressure measurement. How important was that? And what we found was that for the majority of people, so those people with normal blood pressure, resting for two minutes or not resting at all, really led to a blood pressure measurement that was just as good as when you rested for five minutes. However, for those individuals who had a high blood pressure above 1 40/90 resting for five minutes really was important to make sure that their blood pressure was indeed accurate. We thought that this study was particularly important for those who are conducting large scale screening um because this would allow them to measure more patients blood pressure in a short period of time. The second trial that we completed was designed to look at the impact of cuff size and blood pressure measurement, we wanted to know what would happen if every patient that came into an office with and had their blood pressure measured with a regular adult cuff. What would happen to the blood pressure measurement? This is something that we often will see in a clinical setting where there is one device with a regular adult cuff that's already attached. What we found was that this led to substantial measurement, inaccuracy patients in whom a large adult cuff or in whom an actual large adult cuff were actually appropriate for their arm, had their blood pressures overestimated by 10 and 20 millimeters of mercury, respectively. And for those patients in whom a small adult cuff was appropriate using a regular adult cuff. Underestimated their blood pressure by 3.5 millimeters of mercury. The last two trials that we are currently conducting are designed to determine the impact of arm, position on blood pressure measurement, accuracy and on environment and noise on blood pressure measurement accuracy. We're specifically trying to determine the impact of blood pressure measurement on having your arm positioned in such a way where the cuff is at heart level versus when it's resting in your lap or resting at your side, um and then also the impact of being an allowed busy environment versus being in a quiet private room. When your blood pressure is being measured. It is our hope that by the end of all four trials we will be able to inform not only future clinical practice guidelines, but we will also be able to make it easier for large scale screening initiatives to conduct blood pressure measurement in many people so that we can make a difference in terms of decreasing the burden of hypertension across the globe and in terms of preventing cardiovascular disease across the lifespan.