title: Beat-by-beat assessment of cardiac afterload using descending aortic velocity-pressure loop during general anesthesia: a pilot study.
abstract: Continuous cardiac afterload evaluation could represent a useful tool during general anesthesia (GA) to titrate vasopressor effect. Using beat to beat descending aortic pressure(P)/flow velocity(U) loop obtained from esophageal Doppler and femoral pressure signals might allow to track afterload changes. Methods We defined three angles characterizing the PU loop (alpha, beta and Global After-Load Angle (GALA)). Augmentation index (AIx) and total arterial compliance (Ctot) were measured via radial tonometry. Peripheral Vascular Resistances (PVR) were also calculated. Twenty patients were recruited and classified into low and high cardiovascular (CV) risk group. Vasopressors were administered, when baseline mean arterial pressure (MAP) fell by 20%. Results We studied 118 pairs of pre/post bolus measurements. At baseline, patients in the lower CV risk group had higher cardiac output (6.1 ± 1.7 vs 4.2 ± 0.6 L min; p = 0.005), higher Ctot (2.7 ± 1.0 vs 2.0 ± 0.4 ml/mmHg, p = 0.033), lower AIx and PVR (13 ± 10 vs 32 ± 11% and 1011 ± 318 vs 1390 ± 327 dyn s/cm5; p < 0.001 and p = 0.016, respectively) and lower GALA (41 ± 15 vs 68 ± 6°; p < 0.001). GALA was the only PU Loop parameter associated with Ctot, AIx and PVR. After vasopressors, MAP increase was associated with a decrease in Ctot, an increase in AIx and PVR and an increase in alpha, beta and GALA (p < 0.001 for all). Changes in GALA and Ctot after vasopressors were strongly associated (p = 0.004). Conclusions PU Loop assessment from routine invasive hemodynamic optimization management during GA and especially GALA parameter could monitor cardiac afterload continuously in anesthetized patients, and may help clinicians to titrate vasopressor therapy.
authors.affiliation: Department of Anesthesiology and Critical Care, Anesthesiology - Intensive care - SMUR Department, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique-Hôpitaux de Paris, Paris, France. vallee.fabrice@gmail.com.|INSERM UMR-942, Paris, France. vallee.fabrice@gmail.com.|Paris Diderot University, Paris, France. vallee.fabrice@gmail.com.|LMS, Ecole Polytechnique, CNRS, Université Paris-Saclay, Saclay, France. vallee.fabrice@gmail.com.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Vallée
authors.affiliation: Department of Anesthesiology and Critical Care, Anesthesiology - Intensive care - SMUR Department, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique-Hôpitaux de Paris, Paris, France.|INSERM UMR-942, Paris, France.|Paris Diderot University, Paris, France.|Inria, Paris Saclay University, Saclay, France.
authors.forename: Arthur
authors.initials: A
authors.lastname: Le Gall
authors.affiliation: Department of Anesthesiology and Critical Care, Anesthesiology - Intensive care - SMUR Department, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique-Hôpitaux de Paris, Paris, France.|INSERM UMR-942, Paris, France.|Paris Diderot University, Paris, France.|Inria, Paris Saclay University, Saclay, France.
authors.forename: Jona
authors.initials: J
authors.lastname: Joachim
authors.affiliation: Department of Anesthesiology and Critical Care, Anesthesiology - Intensive care - SMUR Department, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique-Hôpitaux de Paris, Paris, France.|INSERM UMR-942, Paris, France.|Paris Diderot University, Paris, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Passouant
authors.affiliation: Department of Anesthesiology and Critical Care, Anesthesiology - Intensive care - SMUR Department, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique-Hôpitaux de Paris, Paris, France.|Paris Diderot University, Paris, France.
authors.forename: Joaquim
authors.initials: J
authors.lastname: Matéo
authors.affiliation: Department of Anesthesiology and Intensive Care, Service de Réanimation et Surveillance Continue, Saint Brieuc, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Mari
authors.affiliation: Pulse Wave Consulting, St Leu la Foret, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Millasseau
authors.affiliation: Department of Anesthesiology and Critical Care, Anesthesiology - Intensive care - SMUR Department, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique-Hôpitaux de Paris, Paris, France.|INSERM UMR-942, Paris, France.|Paris Diderot University, Paris, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Mebazaa
authors.affiliation: Department of Anesthesiology and Critical Care, Anesthesiology - Intensive care - SMUR Department, St-Louis-Lariboisière-Fernand Widal University Hospitals, Assistance Publique-Hôpitaux de Paris, Paris, France.|INSERM UMR-942, Paris, France.|Paris Diderot University, Paris, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Gayat
mesh_terms: D000328:Adult; D000368:Aged; D000768:Anesthesia, General / Q000379:methods*; D001011:Aorta; D062186:Arterial Pressure / Q000187:drug effects*; D001158:Arteries; D001783:Blood Flow Velocity; D001794:Blood Pressure; D002302:Cardiac Output / Q000187:drug effects*; D002318:Cardiovascular Diseases / Q000517:prevention & control; D005260:Female; D006333:Heart Failure; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D010865:Pilot Projects; D011446:Prospective Studies; D063177:Pulse Wave Analysis / Q000379:methods*; D012307:Risk Factors; D013997:Time Factors; D059289:Vascular Stiffness; D014662:Vasoconstrictor Agents
chemical_list: D014662:Vasoconstrictor Agents
keywords: Arteries; Blood flow velocity; Compliance; Pressure; Pulse; Ventricular function, Left