Noradrenaline modifies arterial reflection phenomena and left ventricular efficiency in septic shock patients : A prospective observational study

• Purpose: To determine whether noradrenaline alters the arterial pressure reflection phenomena in septic shock patients and the effects on left ventricular (LV) efficiency.Material and methods: Thirty-seven septic shock patients with a planned change in noradrenaline dose. Timing and magnitude (Reflection Magnitude and Augmentation Index) of arterial reflections were evaluated. Total, steady, and oscillatory LV power (also expressed as fraction of the total power), subendocardial viability ratio (SEVR), energy efficiency and transmission ratios were used as a marker of LV efficiency.Results: An incremental change in noradrenaline increased Reflection Magnitude [0.28(0.09) to 0.31(0.1], Augmentation Index [-6.4(23.6) to 4.8(20.7)%], and LV total power [0.79(IQR:0.47-1) to 0.98(IQR:0.57-127) W], all p < 0.001; whereas decreased arrival time of reflected waves [from 95(87 to 121) to 83(79 to 101)ms; p < 0.001]. Variables of LV performance showed a decreased efficiency: oscillatory fraction and energy efficiency ratio increased [20.9(5.7) to 22.8(4.9)%, and 82(1.7) to 10.1(2) mW.min.litre(-1); p < 0.001, respectively]; and energy transmission ratio and SEVR decreased [73.8(9.9) to 72(9.8)% and 146(IQR:113-188) to 143 (IQR:109-172)%, p = 0.003 and p = 0.041, respectively].Conclusions: Noradrenaline increased reflection phenomena, increasing LV workload and worsening LV performance in septic shock patients. These conditions could explain the detrimental effects during long-term use of noradrenaline.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Anestesi och intensivvård (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Anesthesiology and Intensive Care (hsv//eng)

Keyword

Septic shock

Noradrenaline

Arterial pressure

Pulse wave analysis

Pulse wave velocity

Publication and Content Type

ref (subject category)

art (subject category)