Piha S J
Research Centre, Social Insurance Institution, Turku, Finland.
Clin Physiol. 1994 Jul;14(4):411-7. doi: 10.1111/j.1475-097x.1994.tb00400.x.
The effect of acute dose of caffeine (4 mg kg-1) on cardiovascular autonomic responses were studied in 10 healthy subjects. Standard cardiovascular reflex tests were used during which heart rate and blood pressure were continuously measured. Each subject was tested twice in a random order, with and without prior use of caffeine. It was found that immediate heart rate responses following standing up were lower under influence of caffeine. Blood pressures were systematically, although non-significantly, higher and blood pressure responses in isometric handgrip test stronger when caffeine was used before testing. It is suggested that caffeine should not be used before autonomic testing. This is especially important when the test(s) are performed for research purposes or in order to study the blood pressure responses. If the tests are made for diagnostic purposes the following rules should be adopted: (1) if the subject has used caffeine before testing but all heart rate responses are within normal ranges, it can be assumed that the subject does not have cardiac parasympathetic neuropathy and retesting is not necessary: (2) if the patient has used caffeine before testing and the results suggest presence of autonomic neuropathy, the patient must be retested without the prior use of caffeine.
在10名健康受试者中研究了急性剂量咖啡因（4毫克/千克）对心血管自主反应的影响。使用标准心血管反射测试，在此期间持续测量心率和血压。每个受试者以随机顺序进行两次测试，一次在使用咖啡因之前，一次在不使用咖啡因的情况下。结果发现，在咖啡因的影响下，站立后的即时心率反应较低。在测试前使用咖啡因时，血压系统性地升高，尽管无统计学意义，并且等长握力测试中的血压反应更强。建议在自主测试前不要使用咖啡因。当测试用于研究目的或为了研究血压反应时，这一点尤为重要。如果测试是用于诊断目的，则应采用以下规则：（1）如果受试者在测试前使用了咖啡因，但所有心率反应都在正常范围内，可以假设该受试者没有心脏副交感神经病变，无需重新测试；（2）如果患者在测试前使用了咖啡因且结果提示存在自主神经病变，则患者必须在不预先使用咖啡因的情况下重新测试。
