Focused Cardiac Ultrasound Findings of Fluid Tolerance and Fluid Resuscitation in Septic Shock

Cardiopulmonary Ultrasound to Predict Care Escalation in Early Sepsis: A Pilot Study

BACKGROUND

It is challenging to identify emergency department (ED) patients with sepsis who will require resources such as positive-pressure ventilation, vasopressors, or intensive care unit (ICU) admission.

OBJECTIVES

Describe the correlation of cardiopulmonary ultrasound (CPUS) with need for care escalation.

METHODS

Single center, prospective, observational study of adult patients with suspected sepsis. CPUS assessed left ventricular systolic function (LVF), right ventricular (RV) size and function, inferior vena cava (IVC) collapsibility, and thoracic B lines. The primary composite outcome was need for care escalation within 12 hours of ED presentation defined as: ICU admission or positive-pressure ventilation or vasopressor infusion.

RESULTS

A total of 92 patients were enrolled; 18 (19.6%) required care escalation. A logistic regression model identified the presence of ≥4 thoracic B-lines as a statistically significant predictor of care escalation (OR 7.8, 95% CI [1.3-26.4], p = 0.002). Other features positively correlated with care escalation were: reduced LVF (OR 4.26, 95% CI [0.06-12.9], p = 0.14), and dilated RV size (OR 2.8, 95% CI [0.4-11.8], p = 0.16). A retrospective stepwise regression model incorporating these three variables to predict care escalation showed an AUROC = 0.75 (95% CI [0.63-0.88]). When 2 or more variables were abnormal the model showed excellent specificity of 95% (LR+ 6.2), but low sensitivity of 33% (LR- 0.7).

CONCLUSIONS

In patients with concern for sepsis early findings of ≥4 B-lines is associated with care escalation. Combining this finding with LVF and RV size assessment improves the positive predictive power and may be useful in rapid identification of patients likely to require care escalation.

Coexistence of a fluid responsive state and venous congestion signals in critically ill patients: a multicenter observational proof-of-concept study

BACKGROUND

Current recommendations support guiding fluid resuscitation through the assessment of fluid responsiveness. Recently, the concept of fluid tolerance and the prevention of venous congestion (VC) have emerged as relevant aspects to be considered to avoid potentially deleterious side effects of fluid resuscitation. However, there is paucity of data on the relationship of fluid responsiveness and VC. This study aims to compare the prevalence of venous congestion in fluid responsive and fluid unresponsive critically ill patients after intensive care (ICU) admission.

METHODS

Multicenter, prospective cross-sectional observational study conducted in three medical-surgical ICUs in Chile. Consecutive mechanically ventilated patients that required vasopressors and admitted < 24 h to ICU were included between November 2022 and June 2023. Patients were assessed simultaneously for fluid responsiveness and VC at a single timepoint. Fluid responsiveness status, VC signals such as central venous pressure, estimation of left ventricular filling pressures, lung, and abdominal ultrasound congestion indexes and relevant clinical data were collected.

RESULTS

Ninety patients were included. Median age was 63 [45-71] years old, and median SOFA score was 9 [7-11]. Thirty-eight percent of the patients were fluid responsive (FR+), while 62% were fluid unresponsive (FR-). The most prevalent diagnosis was sepsis (41%) followed by respiratory failure (22%). The prevalence of at least one VC signal was not significantly different between FR+ and FR- groups (53% vs. 57%, p = 0.69), as well as the proportion of patients with 2 or 3 VC signals (15% vs. 21%, p = 0.4). We found no association between fluid balance, CRT status, or diagnostic group and the presence of VC signals.

CONCLUSIONS

Venous congestion signals were prevalent in both fluid responsive and unresponsive critically ill patients. The presence of venous congestion was not associated with fluid balance or diagnostic group. Further studies should assess the clinical relevance of these results and their potential impact on resuscitation and monitoring practices.