Um estudo randomizado cruzado foi publicado na revista JAMA sobre a importância de escolher um manguito de esfigmomanômetro de tamanho correto com base na circunferência do braço do paciente.

O estudo randomizado cruzado, também conhecido como crossover, tem um desenho longitudinal em que os participantes são submetidos a uma série de tratamentos ou exposições distintas. Nesse modelo, os próprios participantes atuam como seus controles, o que potencializa a precisão estatística dos resultados. Isso os diferencia dos estudos randomizados não cruzados ou de grupos paralelos, nos quais os grupos experimental e controle são distintos.

JAMA Intern Med

Effects of Cuff Size on the Accuracy of Blood Pressure Readings: The Cuff(SZ) Randomized Crossover Trial

Junichi Ishigami, Jeanne Charleston, Edgar R Miller 3rd, Kunihiro Matsushita, Lawrence J Appel, Tammy M Brady

Affiliations expand

• PMID: 37548984
• PMCID: PMC10407761 (available on 2024-08-07)
• DOI: 10.1001/jamainternmed.2023.3264

Abstract

Importance: Clinical practice guidelines recommend selecting an appropriately sized cuff based on mid-arm circumference prior to measuring blood pressure (BP). To our knowledge, the effect of miscuffing on BP measurement when using an automated BP device has not been quantified.

Objective: To determine the effect of using a regular BP cuff vs an appropriately sized BP cuff on automated BP readings.

Design, setting, and participants: This randomized crossover trial of community-dwelling adults with a wide range of mid-arm circumferences took place between March 16 and October 25, 2021, in Baltimore, Maryland. Participants were recruited via BP screening events at a public food market and a senior housing facility, targeted mailings to prior research participants, placement of study brochures in hypertension clinics at Johns Hopkins University, and referrals from physicians providing hypertension care to adults.

Interventions: Participants underwent 4 sets of triplicate BP measurements, with the initial 3 sets using an appropriate, too-small, or too-large BP cuff in random order; the fourth set of triplicate measurements was always completed with an appropriate BP cuff.

Main outcomes and measures: The primary outcome was the difference in mean BP when measured with a regular BP cuff compared with an appropriate BP cuff. The secondary outcome was the difference in BP when using too-small or too-large BP cuffs vs an appropriate BP cuff across all cuff sizes. Results were also stratified by systolic BP (≥130 mm Hg vs <130 mm Hg) and body mass index (calculated as weight in kilograms divided by height in meters squared; ≥30 vs <30).

Results: A total of 195 adults (mean [SD] age, 54 [16] years; 67 [34%] male; 132 [68%] Black; 100 [51%] with hypertension) were randomized for inclusion. Among individuals requiring a small BP cuff, use of a regular BP cuff resulted in a statistically significant lower BP reading (mean systolic BP difference, -3.6 [95% CI, -5.6 to -1.7] mm Hg). In contrast, among individuals requiring a large or extra-large BP cuff, use of a regular BP cuff resulted in a statistically significant higher BP reading (mean systolic BP difference, 4.8 [95% CI, 3.0-6.6] mm Hg and 19.5 [95% CI, 16.1-22.9] mm Hg, respectively). For the secondary outcome, BP differences with overcuffing and undercuffing by 1 and 2 cuff sizes were greater among those requiring larger BP cuffs. The results were consistent in stratified analyses by systolic BP and body mass index.

Conclusions and relevance: In this randomized crossover trial, miscuffing resulted in strikingly inaccurate BP measurements. This is particularly concerning for settings where 1 regular BP cuff size is routinely used in all individuals, regardless of arm size. A renewed emphasis on individualized BP cuff selection is warranted.