Association of sublingual microcirculation parameters and capillary refill time in the early phase of ICU admission

Abstract

Background: Recent studies demonstrate the advantage of peripheral perfusion-targeted resuscitation protocols based on capillary refill time (CRT) assessment in critically ill patients. Additionally, sidestream dark field (SDF) imaging could direct visualize sublingual microcirculation of critically ill patients. This study aimed to determine the association between the sublingual microcirculation and CRT in critically ill patients in the early phase of intensive care unit (ICU) admission. Methods: This prospective, observational, pilot study included 282 patients in the ICU of Zhongnan Hospital of Wuhan University between October 2021 and January 2022. All patients underwent simultaneous measurements by CRT and SDF imaging within 24 hours of ICU admission. Additionally, other clinical data such as demographic variables, hemodynamics, laboratory values, treatment, and physiological parameters were also included. The primary outcome was the association between CRT and simultaneous sublingual microcirculation parameters in critically ill patients.Results: Of the 282 included patients, 106 (37.6%) were female, the median (IQR) age was 63 (53-74) years, and the median (IQR) SOFA score was 5 (2-7). Microcirculatory measurements (CRT and SDF imaging) were performed at 10.2 ± 5.7 hours after ICU admission. Significant relationships were observed between the CRT and MFI (r = -0.4430, p < 0.001), PPV (r = -0.3708, p < 0.001), PVD (r = -0.1835, p = 0.0020), and HI (r = 0.4378, p < 0.001). Neither TVD (p = 0.9641) nor De Backer score (p = 0.5202) were related to the CRT. Compare to CRT< 3s group, MFI (2.60 vs. 2.88, p < 0.001), PPV (91.35% vs. 99.10%, p < 0.001), PVD (13.36 mm/mm2 vs. 14.55 mm/mm2, p = 0.002), and HI (0.46 vs. 0.15, p < 0.001) were significantly worse in the CRT ≥ 3s group. The similar results were also found in the sepsis subgroup and the hyperlactatemia subgroup. Prolonged CRT was an independent predictor of 28-days mortality (OR = 1.296; (95%CI, 1.078-1.558); p = 0.006).Conclusions: Our findings suggested that there was a significant and moderate association between CRT and some sublingual microcirculation parameters more related to perfusion (MFI, PPV, and HI) in heterogeneous ICU patients at the early phase of admission.Trial registration: The study was retrospectively registered on November 7, 2021, ChiCTR2100052999.

Capillary Refill Time Versus Sidestream Dark Field: Think Global, Act Local*

“…However, recent studies have questioned the advantage of these protocols over usual care (2–5). The current study by Huang et al (1) continues to inform our thinking around CRT as both a local and global marker of perfusion in the setting of shock resuscitation. The 2019 Andromeda-Shock trial by Hernández et al (6) used the same CRT-targeted protocols for resuscitation against a lactate-targeted group.…”

“…The current study by Huang et al (1) did have its limitations. Unlike the recent studies, this was not a goal-directed resuscitation study; rather, the CRT and MFI measurements were single-spot recordings obtained on average 10 hours after admission.…”

“…KEY WORDS: communication; critical illness; decision-making; end-of-life care; goals of care I n the wake of severe acute brain injury (SABI), families and loved ones are frequently asked to meet with ICU teams to discuss difficult decisions related to life and death. These conversations ideally employ a shared decision-making (SDM) process, with clinicians engaging surrogate decision-makers regarding major treatment decisions that depend on patients' values and personal preferences (1). A growing body of literature has developed around the need to engage families in timely discussions of prognosis and patient preferences (if known) (2), create communication strategies (3), develop and test decision aids (4), and focus interventions on perceived goal-concordant care.…”

“…I n this issue of Critical Care Medicine, Huang et al (1) report their results from a prospective comparison of capillary refill time (CRT) and microvascular flow index (MFI) using sublingual sidestream dark field (SDF) imaging on 282 critically ill patients within 24 hours of ICU admission. CRT was obtained using a microscope glass slide to compress the distal right index phalanx for 10 seconds and measured after release, recording the average of two sequential attempts over 1 minute and defining an abnormal CRT greater than or equal to 3 seconds.…”

Permissive Hypotension Has No Deleterious Impact on Fluid Balance or Kidney Function

“…No mottling was observed in the permissive group, whereas 24% of septic group had mottling around the knee (median score 0 [0-3]). As expected, the severity of septic shock patients was more important with higher Simplified Acute Physiology Score II (60 [45-86] vs. 45 [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46]; p = 0.0001) and higher Sequential Organ Failure Assessment score (7 [5-10] vs. 4 [1][2][3][4][5][6]; p < 0.0001). Organ support therapy was more frequently used in the septic shock group, such as invasive mechanical ventilation (71% vs. 0%; p < 0.0001) and hemodialysis (20% vs. 0%; p = 0.06) (Table 1).…”