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

Critical Care, Mar 2015

Introduction The effect of mean arterial pressure titration to a higher level on microcirculation in septic shock patients with previous hypertension remains unknown. Our goal is to assess the effect of mean arterial pressure titration to a higher level on microcirculation in hypertensive septic shock patients. Methods 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 mean arterial pressure of 65 mmHg were enrolled. Mean arterial pressure was then titrated by norepinephrine from 65 mmHg to the normal level of the patient. In addition to hemodynamic variables, sublingual microcirculation was evaluated by sidestream dark field imaging. Results Nineteen patients were enrolled in the study. Increasing mean arterial pressure from 65 mmHg to normal levels was associated with increased central venous pressure (from 11 ± 4 to 13 ± 4 mmHg, P = 0.002), cardiac output (from 5.4 ± 1.4 to 6.4 ± 2.1 l/minute, P = 0.001), and central venous oxygen saturation (from 81 ± 7 to 83 ± 7%, P = 0.001). There were significant increases in small perfused vessel density (from 10.96 ± 2.98 to 11.99 ± 2.55 vessels/mm2, P = 0.009), proportion of small perfused vessels (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 mean arterial pressure of 65 mmHg. Conclusions Increasing mean arterial pressure from 65 mmHg to normal levels is associated with improved microcirculation in hypertensive septic shock patients. Trial registration Clinicaltrials.gov: NCT01443494; registered 28 September 2011.

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

Xu et al. Critical Care 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 0 Si-Qing Ma 1 Chun Pan 0 Hong-Li He 0 Shi-Xia Cai 0 Shu-Ling Hu 0 Ai-Ran Liu 0 Ling Liu 0 Ying-Zi Huang 0 Feng-Mei Guo 0 Yi Yang 0 Hai-Bo Qiu 0 0 Department of Critical Care Medicine, Nanjing Zhongda Hospital, School of Medicine, Southeast University , Nanjing 210009 , P.R. China 1 Department of Critical Care Medicine, Qinghai Provincial People's Hospital , Xining 810000 , P.R. China Introduction: The effect of mean arterial pressure titration to a higher level on microcirculation in septic shock patients with previous hypertension remains unknown. Our goal is to assess the effect of mean arterial pressure titration to a higher level on microcirculation in hypertensive septic shock patients. Methods: 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 mean arterial pressure of 65 mmHg were enrolled. Mean arterial pressure was then titrated by norepinephrine from 65 mmHg to the normal level of the patient. In addition to hemodynamic variables, sublingual microcirculation was evaluated by sidestream dark field imaging. Results: Nineteen patients were enrolled in the study. Increasing mean arterial pressure from 65 mmHg to normal levels was associated with increased central venous pressure (from 11 4 to 13 4 mmHg, P = 0.002), cardiac output (from 5.4 1.4 to 6.4 2.1 l/minute, P = 0.001), and central venous oxygen saturation (from 81 7 to 83 7%, P = 0.001). There were significant increases in small perfused vessel density (from 10.96 2.98 to 11.99 2.55 vessels/mm2, P = 0.009), proportion of small perfused vessels (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 mean arterial pressure of 65 mmHg. Conclusions: Increasing mean arterial pressure from 65 mmHg to normal levels is associated with improved microcirculation in hypertensive septic shock patients. - Introduction Septic shock is a major cause of death in critically ill patients and is characterized by hypotension and hypoperfusion [1]. Although mortality has been reported to be decreased due to the progress in therapy for septic shock [2,3], microcirculation abnormalities can still be present and contribute to hypoperfusion [4]. Microvascular dysfunction is associated with organ dysfunction and mortality [5,6]; moreover, early improvement in the microcirculation during resuscitation is associated with reduced organ failure [7]. Therefore, therapeutic strategies aimed at improving the microcirculation are warranted to mitigate hypoperfusion and organ failure. Maintaining sufficient perfusion pressure might be an important way to improve the microcirculatory perfusion [8]. As one of the key determinants of perfusion pressure, adequate mean arterial pressure (MAP) might reduce hypoperfusion and organ failure. Correa and colleagues [9] have evaluated the effects of different MAP targets in septic pigs, and show that targeting a MAP between 50 and 60 mmHg in septic shock is associated with increased incidence of acute kidney injury when compared with a target MAP of between 75 and 85 mmHg. Moreover, Badin and colleagues [10] have reported that acute kidney injury is decreased with a MAP of at least 72 mmHg. However, which MAP levels should be targeted to improve microcirculation remains controversial [11-13]. The optimal MAP target in septic shock patients, especially in patients with previous hypertension, is still unknown [14]. The guidelines [15] for treating septic shock have recommended that MAP should be maintained at a level of at least 65 mmHg, and emphasized a higher blood pressure for patients with previous hypertension. A recent published randomized controlled study [16] has shown no difference in mortality in septic shock patients undergoing resuscitation with a high MAP target or a low MAP target. However, among chronic hypertensive patients, those in the high-target group require less renal replacement therapy, indicating that septic shock patients with chronic hypertension might need higher MAP to maintain microcirculation. Our goal was to assess the effect on the microcirculation of MAP titration to normal levels in septic shock patients with previous hypertension. We hypothesized that the increase in MAP from 65 mmHg to the normal levels of patients is associated with improved sublingual microcirculation. Materials and methods Setting This was a single-center, prospective, open-label study conducted in the intensive care unit of a tertiary care teaching hospital. The study protocol was approved by the Ethics Committee (Approval Number: 2011ZDllKY03.0) of Zhongda Hospital, School of Medicine, Southeast University, (...truncated)


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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. A high mean arterial pressure target is associated with improved microcirculation in septic shock patients with previous hypertension: a prospective open label study, Critical Care, 2015, pp. 130, 19, DOI: 10.1186/s13054-015-0866-0