Mort Jane R, Kruse Heather R
College of Pharmacy, South Dakota State University, Sioux Falls, SD 57107, USA.
Ann Pharmacother. 2008 Jan;42(1):105-10. doi: 10.1345/aph.1K337. Epub 2007 Dec 19.
To determine whether patients should wait 30 minutes after caffeine consumption to have their blood pressure measured.
Literature was obtained by searching MEDLINE (1980-September 2007), International Pharmaceutical Abstracts (1980-September 2007), and the Cochrane Database of Systematic Reviews (1994-September 2007). Search terms included caffeine and blood pressure. Literature was also obtained from citations in relevant articles.
Articles that examined caffeine's acute effect on blood pressure were reviewed, with additional focus on caffeine tolerance and hypertensive status.
Caffeine appears to affect blood pressure through adenosine receptor inhibition and an increased release of select neurotransmitters. Caffeine levels peak 30-120 minutes after oral intake and caffeine's half-life is 3-6 hours. The effect of caffeine on blood pressure has been examined for decades, with variable results depending on factors such as population examined (eg, hypertensive status, physical stressors, age) and study design (eg, acute effects, chronic ingestion, retrospective epidemiologic review). Caffeine tolerance diminishes the acute effect of caffeine on blood pressure, and hypertensive individuals are more susceptible to blood pressure changes. Reviews of caffeine's acute effect on blood pressure indicate changes of 3-15 mm Hg systolic and 4-13 mm Hg diastolic. Typically, blood pressure changes occur within 30 minutes, peak in 1-2 hours, and may persist for more than 4 hours.
Having a patient abstain from caffeine for 30 minutes prior to blood pressure monitoring is not adequate to avoid caffeine's potential effects. An alternative approach to blood pressure monitoring would be to ask the patient about recent caffeine consumption and interpret the blood pressure reading based on this information. In addition, healthcare practitioners should provide education regarding caffeine's effects.
确定患者在摄入咖啡因后是否应等待30分钟再测量血压。
通过检索MEDLINE（1980年 - 2007年9月）、国际药学文摘（1980年 - 2007年9月）和Cochrane系统评价数据库（1994年 - 2007年9月）获取文献。检索词包括咖啡因和血压。还从相关文章的参考文献中获取文献。
对研究咖啡因对血压急性影响的文章进行综述，特别关注咖啡因耐受性和高血压状态。
咖啡因似乎通过抑制腺苷受体和增加某些神经递质的释放来影响血压。口服摄入后咖啡因水平在30 - 120分钟达到峰值，其半衰期为3 - 6小时。数十年来一直在研究咖啡因对血压的影响，结果因所研究人群（如高血压状态、身体应激源、年龄）和研究设计（如急性影响、长期摄入、回顾性流行病学综述）等因素而异。咖啡因耐受性会减弱咖啡因对血压的急性影响，高血压个体更容易出现血压变化。关于咖啡因对血压急性影响的综述表明，收缩压变化为3 - 15 mmHg，舒张压变化为4 - 13 mmHg。通常，血压变化在30分钟内出现，1 - 2小时达到峰值，可能持续超过4小时。
让患者在血压监测前30分钟不摄入咖啡因不足以避免咖啡因的潜在影响。血压监测的另一种方法是询问患者近期的咖啡因摄入量，并根据此信息解读血压读数。此外，医疗保健从业者应提供有关咖啡因影响的教育。
