Measurement of blood pressure in children: recommendations and perceptions on cuff selection

. To review some of the recent recommendations on blood pressure (BP) cuff selection, including those by the Task Force and its update, and to survey the perceptions on cuff selection among practitioners.

The study was conducted in two parts. In the first, we selected three brands of commonly used infant, child/pediatric, small adult, adult, and large adult BP cuffs. From the median width of each, we derived the required upper arm length (UAL) for the cuff to cover three quarters or two thirds of the UAL, and with the help of a published normal UAL at various ages, we matched the derived UAL with the corresponding age at the 50th percentile. Similarly, we derived the midupper arm circumference (UAC) so that the available cuffs would cover 40% of the UAC, and by using the published normal UAC at various ages, we matched the derived UAC with the corresponding age at the 50th percentile. The second part of the study involved a survey by multiple choice questionnaire mailed to 400 hospital- and office-based pediatricians, residents, and nurses at the Children's Hospital of Michigan. Included in the survey were questions about the age at which practitioners would choose the cuffs described above; the minimum age they would consider using an adult cuff in a pediatric patient with an average height and weight; selecting a cuff using UAL as a criterion; selecting a large versus a small cuff when the appropriate cuff size is not available; and the Task Force definition of hypertension.

Using three quarters of the UAL as a criterion, it seems that a large adult cuff should be appropriate for an average-size 6-year-old child and that using two thirds of UAL as a criterion, the cuff should be appropriate for an average-size 7- to 8-year-old child. Similarly, by using 40% of the mid-UAC as a criterion, an adult cuff would be of no use in an average pediatric patient at any age. Our survey revealed that 57% of practitioners would consider using a neonatal cuff for patients up to 1 month of age, 65% would use an infant cuff for those 1 year of age, 49% would use a child/pediatric cuff for those 5 years of age, and 84% would use a small adult cuff for those 10 years of age and older. Most (83%) of the practitioners would consider using an adult cuff in children 11 years of age and older. Practitioners are likely to use a smaller cuff than is appropriate by two thirds or three quarters of UAL criteria, and a larger cuff than is appropriate, particularly in older children, by 40% of UAC criteria. Using UAL as a criterion, a majority (59%) of practitioners use cuffs that cover two thirds of the distance between the axilla and the cubital fossa. Ninety-two percent of practitioners believe that a smaller cuff causes a moderate to significant increase in the BP reading, and 55% believe that a larger cuff causes a similar decrease in the BP reading. A significant number of practitioners (44%) did not know the Task Force definition of hypertension, including 42% of attendings, 44% of residents, and 50% of nurses.

The Task Force and the Working Group recommendations on BP cuff selection need to be reviewed. A new multicenter study, using uniform criteria for cuff selection, may be necessary to establish the accuracy of the published nomogram on normal BP in children. More awareness is required on part of practitioners of the current recommendations on BP measurement and the definition of hypertension. Finally, the labeling of BP cuffs as infant, pediatric, small adult, adult, and large adult is misleading, and such designations should be eliminated. Cuff sizes should be standardized, indicate bladder size, and be uniformly color-coded for convenience.