Manuel Ignacio Monge García1, Arnoldo Santos2, Beatriz Diez Del Corral3, Pedro Guijo González3, Manuel Gracia Romero3, Anselmo Gil Cano3, Maurizio Cecconi4. 1. Servicio de Cuidados Intensivos, Hospital SAS de Jerez, C/Circunvalación s/n, 11407 Jerez de la Frontera, Spain. Electronic address: ignaciomonge@gmail.com. 2. Hedenstierna Laboratory, Department of Surgical Sciences, Section of Anaesthesiology and Critical Care, Uppsala University, Akademiska sjukhuset ing 40 2 tr, 751 85 Uppsala, Sweden; CIBER de enfermedades respiratorias (CIBERES), Avd. Monforte de Lemos 3-5, Pabellón 11, planta 0, 28029 Madrid, Spain. 3. Servicio de Cuidados Intensivos, Hospital SAS de Jerez, C/Circunvalación s/n, 11407 Jerez de la Frontera, Spain. 4. Department of Intensive Care Medicine, St. George's Healthcare NHS Trust and St George's University of London, Tooting, London SW17 0QT, UK.
Abstract
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:0.57-1.27)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 8.2(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.
PURPOSE: To determine whether noradrenaline alters the arterial pressure reflection phenomena in septic shockpatients and the effects on left ventricular (LV) efficiency. MATERIAL AND METHODS: Thirty-seven septic shockpatients 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:0.57-1.27)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 8.2(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 shockpatients. These conditions could explain the detrimental effects during long-term use of noradrenaline.