The following is a summary of “Effect on capillary refill time of volume expansion and increase of the norepinephrine dose in patients with septic shock,” published in the November 2023 issue of Critical Care by Fage et al.

Researchers started a retrospective study to assess the effects of volume expansion and norepinephrine on capillary refill time (CRT) in patients with septic shock.

They observed mean arterial pressure (MAP) cardiac index (CI) and conducted 5 consecutive CRT measurements (using a video method with standardized pressure on the fingertip) in a group of 69 patients with septic shock. 33 patients received 500 mL saline, and 36 patients received a norepinephrine dose increase, both pre- and post-treatment. Fluid responders were identified as those showing a CI increase of ≥15%, while norepinephrine responders were characterized by a MAP increase of ≥15%.

The results showed a significant change in CRT was considered if it exceeded 23%. With volume expansion, patients with a baseline CRT < 3 s (n = 7) and almost all patients with a baseline CRT ≥ 3 s and an increase in fluid resulting in CI < 15% (n = 13 “fluid non-responders”) had no average change in CRT. Among fluid responders with a baseline CRT ≥ 3 s (n = 13), CRT decreased in 8 patients and stayed the same in the others, indicating a discrepancy between CI and CRT responses. Patients included > 24 hours after starting norepinephrine were more frequent in those displaying such a discrepancy compared to others (60% vs. 0%). Except for one patient, norepinephrine did not significantly change CRT if the baseline CRT was ≥ 3 s and the increase in MAP < 15% (n = 6). In norepinephrine responders with extended baseline CRT (n = 11), CRT rose in 4 patients and remained stable in the rest, highlighting a difference in MAP and CRT reactions.

They concluded that in septic shock patients with prolonged CRT, it rarely improved when volume expansion increased cardiac output <15% and rising norepinephrine increased MAP <15%.

Source: ccforum.biomedcentral.com/articles/10.1186/s13054-023-04714-0