Comparison of invasive dynamic blood pressure between superior mesenteric artery and common carotid artery in rats.

BACKGROUND

The purpose of this study was to identify the consistency of invasive dynamic blood pressure (BP) monitoring between the superior mesenteric artery (SMA) and the common carotid artery (CCA).

METHODS

Eight male Sprague-Dawley rats were cannulated in SMA and CCA simultaneously for BP monitoring, respectively. The abdominal aorta was prepared for the induction of BP change through clamping/de-clamping by a microvascular clip. The dynamic BP monitoring was performed by a polygraph system. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) values would be recorded during different time periods: the baseline (T1), the increasing period after clamping (T2), the platform period during clamping (T3), the decreasing period after de-clamping (T4), and the final platform period (T5). Three trials were performed on each rat with 15-minute intervals between consecutive monitoring.

RESULTS

Systolic BP showed no significant differences between SMA and CCA. However, significant difference was found in diastolic blood pressure except at T5 (P=0.534). Mean arterial pressure of two arteries were significantly different only at T1 (P=0.015). The strength of association was significantly high between BP measurements through SMA and CCA (P<0.001). The Bland-Altman analyses showed that mean bias of MAP changed no more than 5 mmHg and standard deviation less than 8 mmHg during T2 and T4, respectively.

CONCLUSION

The study indicates SMA might be an alternative site for invasive BP monitoring during abdominal aorta occlusion and release, especially in cerebrovascular-related research.