已显示去氧肾上腺素影响眼内压(IOP),但其作用机制知之甚少。然而,其作为血管收缩剂的作用提示可能对巩膜上静脉压(EVP)产生影响。在这项研究中,我们评估了去氧肾上腺素对健康受试者EVP和IOP的影响。
包括20名受试者的40只眼。每个受试者以1分钟的间隔在一只眼睛中接受3滴2.5%的去氧肾上腺素。同伴的眼睛作为控制。血压,心率,在基线时测量双眼的IOP和EVP,15分钟,和滴注去氧肾上腺素60分钟后。通过肺活量测量法测量眼压。使用计算机控制的巩膜上静脉压计评估EVP。IOP的变化,执行副总裁,血压,通过配对t检验分析15分钟和60分钟时的心率。
滴注去氧肾上腺素后15分钟,治疗眼(P=0.001)和对照组眼(P=0.01)的IOP均增加,并在60分钟时恢复到基线。15分钟时的IOP变化在两组之间没有显着差异。经治疗的眼睛中的EVP在15分钟时没有变化(P=0.8),但在60分钟时显著降低(P<0.001)。在控制的眼睛,EVP在任何时候都没有变化(P>0.6)。滴注去氧肾上腺素后,收缩压和舒张压以及心率与基线相比没有显着变化。
与局部去氧肾上腺素相关的IOP升高不是由健康受试者的EVP增加引起的。相反,EVP降低与去氧肾上腺素,但机制尚待确定。
Phenylephrine has been shown to affect intraocular pressure (IOP) but the mechanism of action is poorly understood. However, its action as a vasoconstrictor suggests possible effects on episcleral venous pressure (EVP). In this study, we evaluated the effect of phenylephrine on EVP and IOP in healthy subjects.
Forty eyes of 20 subjects were included. Each subject received 3 drops of phenylephrine 2.5% in one eye at 1-minute intervals. The fellow eye served as control. Blood pressure, heart rate, and IOP and EVP of both eyes were measured at baseline, 15 minutes, and 60 minutes after instillation of phenylephrine. IOP was measured by pneumatonometry. EVP was assessed by using a computer-controlled episcleral venomanometer. Changes in IOP, EVP, blood pressure, and heart rate at 15 and 60 minutes were analyzed by paired t-tests.
IOP increased 15 minutes after instillation of phenylephrine in both treated (P = 0.001) and control eyes (P = 0.01) and returned to baseline at 60 minutes. The change in IOP at 15 minutes was not significantly different between the 2 groups. EVP in treated eyes was unchanged at 15 minutes (P = 0.8) but decreased significantly at 60 minutes (P < 0.001). In control eyes, there was no change in EVP at any time (P > 0.6). There were no significant changes from baseline in systolic and diastolic blood pressure and heart rate after instillation of phenylephrine.
IOP elevation associated with topical phenylephrine is not caused by an increase in EVP in healthy subjects. Instead, EVP decreases with phenylephrine, but the mechanism remains to be determined.