Sepsis-related hypotension is typically managed with intravenous fluid administration, but excessive fluid can precipitate complications such as pulmonary edema and respiratory failure. A bedside, noninvasive method to predict which patients will increase cardiac output in response to fluids—i.e., are fluid responsive—could help clinicians tailor resuscitation and limit fluid-related harm.
Monitoring changes in end-tidal carbon dioxide (ETCO2) during a passive leg raise (PLR) is one proposed noninvasive approach. PLR transiently shifts venous blood from the legs to the central circulation, simulating a fluid bolus; a corresponding rise in ETCO2 may reflect an increase in pulmonary blood flow and thus identify patients likely to benefit from additional intravenous fluids.
The study aimed to determine the effectiveness of PLR combined with ETCO2 monitoring after initial fluid resuscitation among emergency department (ED) patients with sepsis. The investigation included both spontaneously breathing and intubated (mechanically ventilated) patients presenting to the ED with sepsis.
This was a quantitative comparative cohort study conducted using two groups drawn from the ED setting:
Within the intervention cohort, investigators conducted supplementary analyses by categorizing patients according to whether they met criteria for fluid responsiveness: responders (n = 28) and nonresponders (n = 49).
Details such as the precise ETCO2 change threshold used to define responsiveness, the timing and duration of PLR, and the specific ETCO2 monitoring protocol were not reported in the PubMed abstract and therefore are not available in this source.
The primary comparisons reported included total amounts of fluid administered and selected clinical outcomes between the preintervention and intervention cohorts. Supplementary analyses compared total fluid administration between PLR responders and PLR nonresponders. Reported statistical findings in the abstract include P values for group comparisons.
Key results reported in the abstract are:
Patients who received PLR (intervention cohort) had a higher total fluid volume administered than the preintervention (no-PLR) group (P < .001).
Tachycardia was more common in the preintervention group than in the intervention group (P < .001).
In the PLR cohort, 64% of patients were identified as negative fluid responders (i.e., did not meet criteria for fluid responsiveness based on the PLR/ETCO2 assessment).
Among the intervention cohort, those identified as nonresponders had a lower mean total fluid administration compared with responders; however, this difference did not reach statistical significance (P = .06).
The abstract does not provide absolute fluid volumes, measures of central tendency or spread for ETCO2 changes, nor other clinical outcome metrics beyond those summarized above.
The authors conclude that PLR with ETCO2 monitoring can be instrumental in assessing fluid responsiveness among ED patients with sepsis who are either spontaneously breathing or mechanically ventilated. The method offers a noninvasive bedside assessment that can be performed by nursing staff in the ED setting.
Limitations and gaps in the information available from the PubMed abstract include:
These omissions mean that implementation decisions should rely on the full-text article for operational details and on broader guideline context.
PLR combined with ETCO2 monitoring was feasible in an ED cohort that included spontaneously breathing and intubated patients with sepsis.
In this study sample, 64% of patients undergoing PLR were classified as nonresponders; nonresponders received lower mean total fluids, though that difference was not statistically significant.
The intervention cohort overall received more fluid than the preintervention cohort, and tachycardia was less common after introducing the PLR protocol.
The abstract supports the potential role of PLR and ETCO2 as noninvasive tools to inform fluid decisions in sepsis, but practitioners should consult the full article for operational thresholds and additional outcome data before changing practice.