Association of Preoperative Basal Inflammatory State, Measured by Plasma suPAR Levels, with Intraoperative Sublingual Microvascular Perfusion in Patients Undergoing Major Non-Cardiac Surgery

Abstract

It remains unknown whether chronic systemic inflammation is associated with impaired microvascular perfusion during surgery. We evaluated the association between the preoperative basal inflammatory state, measured by plasma soluble urokinase-type plasminogen activator receptor (suPAR) levels, and intraoperative sublingual microcirculatory variables in patients undergoing major non-cardiac surgery. Plasma suPAR levels were determined in 100 non-cardiac surgery patients using the suPARnostic® quick triage lateral flow assay. We assessed sublingual microcirculation before surgical incision and every 30 min during surgery using Sidestream Darkfield (SDF+) imaging and determined the De Backer score, the Consensus Proportion of Perfused Vessels (Consensus PPV), and the Consensus PPV (small). Elevated suPAR levels were associated with lower intraoperative De Backer score, Consensus PPV, and Consensus PPV (small). For each ng mL−1 increase in suPAR, De Backer score, Consensus PPV, and Consensus PPV (small) decreased by 0.7 mm−1, 2.5%, and 2.8%, respectively, compared to baseline. In contrast, CRP was not significantly correlated with De Backer score (r = −0.034, p = 0.36), Consensus PPV (r = −0.014, p = 0.72) or Consensus PPV Small (r = −0.037, p = 0.32). Postoperative De Backer score did not change significantly from baseline (5.95 ± 3.21 vs. 5.89 ± 3.36, p = 0.404), while postoperative Consensus PPV (83.49 ± 11.5 vs. 81.15 ± 11.8, p < 0.001) and Consensus PPV (small) (80.87 ± 13.4 vs. 78.72 ± 13, p < 0.001) decreased significantly from baseline. In conclusion, elevated preoperative suPAR levels were associated with intraoperative impairment of sublingual microvascular perfusion in patients undergoing elective major non-cardiac surgery.

Association between mean arterial pressure and sublingual microcirculation during major non‐cardiac surgery: Post hoc analysis of a prospective cohort

“…28 In contrast, there may be an association between microcirculatory tissue perfusion and outcome in high-risk non-cardiac surgery patients. 27,29 The major limitation of our study is that MAP was generally kept above 65 mmHg, which is apparently high enough to maintain normal sublingual perfusion. We were thus unable to identify a hypotensive threshold at which microcirculatory perfusion was compromised.…”

“…Previous studies of sublingual microcirculation during noncardiac surgery also reported considerable heterogeneity in microcirculatory flow among individuals, as well as substantial interindividual variability. 8,26,27 In general, available evidence suggests that microcirculatory perfusion is preserved during general anesthesia and elective non-cardiac surgery when MAP is maintained within a normal range or slightly higher. 28 In contrast, there may be an association between microcirculatory tissue perfusion and outcome in high-risk non-cardiac surgery patients.…”

“…In general, available evidence suggests that microcirculatory perfusion is preserved during general anesthesia and elective non‐cardiac surgery when MAP is maintained within a normal range or slightly higher 28 . In contrast, there may be an association between microcirculatory tissue perfusion and outcome in high‐risk non‐cardiac surgery patients 27,29 …”

“…27 The latter can decrease capillary perfusion and vascular integrity and impair the ability of the microvasculature to coordinate a vasodilatory response. 27,29 .005…”

“…Within this range, microcirculation can be highly adaptive to its cellular environment and can be autoregulated independent of changes in systemic blood pressure 8,26 . However, monitoring of sublingual microcirculation can yield important physiologic information in patients with hypotension, comorbidities, or those with high levels of chronic systemic inflammation 27 . The latter can decrease capillary perfusion and vascular integrity and impair the ability of the microvasculature to coordinate a vasodilatory response 27,29 .…”