A high mean arterial pressure target is associated with improved microcirculation in septic shock patients with previous hypertension: a prospective open label study

Jing-Yuan Xu, Si-Qing Ma, Chun Pan, Hong-Li He, Shi-Xia Cai, Shu-Ling Hu, Ai-Ran Liu, Ling Liu, Ying-Zi Huang, Feng-Mei Guo, Yi Yang, Hai-Bo Qiu

The effect of mean arterial pressure (MAP) titration to a higher level on microcirculation in septic shock patients with previous hypertension remains unknown. Our goal is to assess the effect of MAP titration to a higher level on microcirculation in hypertensive septic shock patients. This is a single-center open label study. Hypertensive patients with septic shock for less than 24 hours after adequate fluid resuscitation and requiring norepinephrine to maintain a MAP of 65 mm Hg were enrolled. Then MAP was titrated by norepinephrine from 65 mm Hg to patients' usual level. In addition to hemodynamic variables, sublingual microcirculation was evaluated by sidestream dark field imaging. Nineteen patients were enrolled in the study. Increasing MAP from 65 mm Hg to patients' usual level was associated with increased central venous pressure (from 11 ± 4 to 13 ± 4 mm Hg, p = 0.002), cardiac output (from 5.4 ± 1.4 to 6.4 ± 2.1 l/min, p = 0.001), central venous oxygen saturation (from 81 ± 7 to 83 ± 7%, p = 0.001). There were significant increases of small perfused vessel density (from 10.96 ± 2.98 to 11.99 ± 2.55 vessels/mm(2), p = 0.009), proportion of small perfused vessel (from 85 ± 18 to 92 ± 14%, p = 0.002), and small microvascular flow index (from 2.45 ± 0.61 to 2.80 ± 0.68, p = 0.009) when compared with a MAP of 65 mm Hg. Increasing MAP from 65 mm Hg to patients' usual level is associated with improved microcirculation in hypertensive septic shock patients. Clinicaltrials.gov NCT01443494 . Registered 28 November 2011.