Ventriculo-arterial (un)coupling in septic shock: Impact of current and upcoming hemodynamic drugs

U-shaped prognostic value of left ventricular-arterial coupling in septic patients: a prospective study

BACKGROUND

Ventricular-arterial coupling (VAC) has garnered increasing interest in critical care. The prognostic significance of left ventricular-arterial coupling (LVAC) in this context remains a topic of debate.

OBJECTIVE

This study aimed to explore the association between LVAC and patient outcomes in sepsis.

METHODS

Patients with sepsis or septic shock admitted to the intensive care unit (ICU) were included. LVAC was evaluated using the arterial elastance (Ea)/left ventricular end-systolic elastance (Ees) ratio. Prognostic indicators, including 30-day mortality, length of ICU stay, mechanical ventilation (MV), changes in delta lactate levels, and oxygen index were also collected.

RESULTS

A total of 388 patients were enrolled in this study. A U-shaped relationship was observed between LVAC and 30-day mortality, with an optimal LVAC value of 1.19 identified. For LVAC values above 1.19, the odds ratio (OR) for 30-day mortality was 1.07 (95% confidence interval [CI] 1.01-1.14). Below this threshold, OR was 0.85 (95% CI 0.73, 0.99). Similarly, in the curve for ICU-free days, a β value of - 8.64 (95% CI - 16.53, - 0.76) was noted for LVAC values over 1.26. For ventilator-free time, the kink point was 1.24, with significant β values on both sides of this threshold [- 226.49 (95% CI - 411.59, - 41.38) and 147.67 (95% CI 12.40, 282.93), respectively].

CONCLUSIONS

This study established U-shaped associations between LVAC and various clinical outcomes in septic patients. Optimizing LVAC could potentially enhance patient prognosis. Given the slight variations in optimal LVAC values across different patient populations, individualized LVAC titration may be beneficial in improving clinical outcomes.

Apelin-13 administration allows for norepinephrine sparing in a rat model of cecal ligation and puncture-induced septic shock

BACKGROUND

Infusion of exogenous catecholamines (i.e., norepinephrine [NE] and dobutamine) is a recommended treatment for septic shock with myocardial dysfunction. However, sustained catecholamine infusion is linked to cardiac toxicity and impaired responsiveness. Several pre-clinical and clinical studies have investigated the use of alternative vasopressors in the treatment of septic shock, with limited benefits and generally no effect on mortality. Apelin-13 (APL-13) is an endogenous positive inotrope and vasoactive peptide and has been demonstrated cardioprotective with vasomodulator and sparing life effects in animal models of septic shock. A primary objective of this study was to evaluate the NE-sparing effect of APL-13 infusion in an experimental sepsis-induced hypotension.

METHODS

For this goal, sepsis was induced by cecal ligation and puncture (CLP) in male rats and the arterial blood pressure (BP) monitored continuously via a carotid catheter. Monitoring, fluid resuscitation and experimental treatments were performed on conscious animals. Based on pilot assays, normal saline fluid resuscitation (2.5 mL/Kg/h) was initiated 3 h post-CLP and maintained up to the endpoint. Thus, titrated doses of NE, with or without fixed-doses of APL-13 or the apelin receptor antagonist F13A co-infusion were started when 20% decrease of systolic BP (SBP) from baseline was achieved, to restore SBP values ≥ 115 ± 1.5 mmHg (baseline average ± SEM).

RESULTS

A reduction in mean NE dose was observed with APL-13 but not F13A co-infusion at pre-determined treatment time of 4.5 ± 0.5 h (17.37 ± 1.74 µg/Kg/h [APL-13] vs. 25.64 ± 2.61 µg/Kg/h [Control NE] vs. 28.60 ± 4.79 µg/Kg/min [F13A], P = 0.0491). A 60% decrease in NE infusion rate over time was observed with APL-13 co-infusion, (p = 0.008 vs NE alone), while F13A co-infusion increased the NE infusion rate over time by 218% (p = 0.003 vs NE + APL-13). Associated improvements in cardiac function are likely mediated by (i) enhanced left ventricular end-diastolic volume (0.18 ± 0.02 mL [Control NE] vs. 0.30 ± 0.03 mL [APL-13], P = 0.0051), stroke volume (0.11 ± 0.01 mL [Control NE] vs. 0.21 ± 0.01 mL [APL-13], P < 0.001) and cardiac output (67.57 ± 8.63 mL/min [Control NE] vs. 112.20 ± 8.53 mL/min [APL-13], P = 0.0036), and (ii) a reduced effective arterial elastance (920.6 ± 81.4 mmHg/mL/min [Control NE] vs. 497.633.44 mmHg/mL/min. [APL-13], P = 0.0002). APL-13 administration was also associated with a decrease in lactate levels compared to animals only receiving NE (7.08 ± 0.40 [Control NE] vs. 4.78 ± 0.60 [APL-13], P < 0.01).

CONCLUSION

APL-13 exhibits NE-sparing benefits in the treatment of sepsis-induced shock, potentially reducing deleterious effects of prolonged exogenous catecholamine administration.

Cardiogenic shock and infection: A lethal combination

BACKGROUND

Cardiogenic shock and sepsis are severe haemodynamic states that are frequently present concomitantly, leading to substantial mortality. Despite its frequency and clinical significance, there is a striking lack of literature on the outcomes of combined sepsis and cardiogenic shock.

METHODS

FRENSHOCK was a prospective registry including 772 patients with cardiogenic shock from 49 centres. The primary endpoint was 1-month all-cause mortality. Secondary endpoints included heart transplantation, ventricular assistance device and all-cause death rate at 1year.

RESULTS

Among the 772 patients with cardiogenic shock included, 92 cases were triggered by sepsis (11.9%), displaying more frequent renal and hepatic acute injuries, with lower mean arterial pressure. Patients in the sepsis group required broader use of dobutamine (90.1% vs. 81.2%; P=0.16), norepinephrine (72.5% vs. 50.8%; P<0.01), renal replacement therapy (29.7% vs. 14%; P<0.01), non-invasive ventilation (36.3% vs. 24.4%; P=0.09) and invasive ventilation (52.7% vs. 35.9%; P=0.02). Sepsis-triggered cardiogenic shock resulted in higher 1-month (41.3% vs. 24.0%; adjusted hazard ratio: 1.94, 95% confidence interval: 1.36-2.76; P<0.01) and 1-year (62.0% vs. 42.9%; adjusted hazard ratio 1.75, 95% confidence interval 1.32-2.33; P<0.01) all-cause death rates. No significant difference was found at 1year for heart transplantation or ventricular assistance device (8.7% vs. 10.3%; adjusted odds ratio 0.72, 95% confidence interval 0.32-1.64; P=0.43). In patients with sepsis-triggered cardiogenic shock, neither the presence of a preexisting cardiomyopathy nor the co-occurrence of other cardiogenic shock triggers had any additional impact on death.

CONCLUSIONS

The association between sepsis and cardiogenic shock represents a common high-risk scenario, leading to higher short- and long-term death rates, regardless of the association with other cardiogenic shock triggers or the presence of preexisting cardiomyopathy.